Freyja Workflow Series

Quick Facts

Workflow Type	Applicable Kingdom	Last Known Changes	Command-line Compatibility	Workflow Level	Dockstore
Genomic Characterization	SARS-CoV-2, Viral	v4.1.0	Yes	Sample-level, Set-level	Freyja_FASTQ_PHB, Freyja_Plot_PHB, Freyja_Dashboard_PHB

Freyja Overview

Freyja is a tool for analysing viral mixed sample genomic sequencing data. Developed by Joshua Levy from the Andersen Lab, it performs two main steps:

1. Variant Frequency Estimation: Freyja calculates the frequencies of single nucleotide variants (SNVs) in the genomic sequencing data.
2. Depth-Weighted Demixing: It separates mixed populations of viral subtypes using a depth-weighted statistical approach, estimating the proportional abundance of each subtype in the sample based on the frequencies of subtype-defining variants.

Additional post-processing steps can produce visualizations of aggregated samples.

Wastewater and more

The typical use case of Freyja is to analyze mixed SARS-CoV-2 samples from a sequencing dataset, most often wastewater, but the tool is not limited to this context. With the appropriate reference genomes and barcode files, Freyja can be adapted for other pathogens, including MPXV, Influenza, RSV, and Measles.

Default Values

The defaults included in the Freyja workflows reflect this use case but can be adjusted for other pathogens. See the Running Freyja on other pathogens section for more information. Please be aware this is an experimental feature and we cannot guarantee complete functionality at this time.

Figure 1: Workflow diagram for Freyja Suite of workflows

Figure 1

Depending on the type of data (Illumina or Oxford Nanopore), the Read QC and Filtering steps, as well as the Read Alignment steps use different software. The user can specify if the barcodes and lineages file should be updated with freyja update before running Freyja or if bootstrapping is to be performed with freyja boot.

Four workflows have been created that perform different parts of Freyja:

• Freyja_FASTQ_PHB
• Freyja_Plot_PHB
• Freyja_Dashboard_PHB

The main workflow is Freyja_FASTQ_PHB (Figure 1). Depending on the type of input data (Illumina paired-end, Illumina single-end or ONT), it runs various QC modules before aligning the sample with either BWA (Illumina) or minimap2 (ONT) to the provided reference file, followed by iVar for primer trimming. After the preprocessing is completed, Freyja is run to generate relative lineage abundances (demix) from the sample. Optional bootstrapping may be performed.

Data Compatability

The Freyja_FASTQ_PHB workflow is compatible with the following input data types:

- Ilumina Single-End
- Illumina Paired-End
- Oxford Nanopore

Two options are available to visualize the Freyja results: Freyja_Plot_PHB and Freyja_Dashboard_PHB. Freyja_Plot_PHB aggregates multiple samples using output from Freyja_FASTQ_PHB to generate a plot that shows fractional abundance estimates for all samples. including the option to plot sample collection date information. Alternatively, Freyja_Dashboard_PHB aggregates multiple samples using output from Freyja_FASTQ_PHB to generate an interactive visualization. This workflow requires an additional input field called viral load, which is the number of viral copies per liter.

Freyja, Sequencing Platforms and Data Quality

The choice of sequencing platform and the quality of the data directly influence Freyja's performance. High-accuracy platforms like Illumina provide reliable SNV detection, enhancing the precision of lineage abundance estimates. In contrast, platforms with higher error rates, such as Nanopore, whilst it has improved greatly in the recent years, may introduce uncertainties in variant calling, affecting the deconvolution process. Sequencing depth requirements will increase as the quality of the sequencing data decreases. A rational target depth is 100X coverage for sequencing data with Q-scores in the range of 25-30.

Additionally, inadequate sequencing depth can hinder Freyja's ability to differentiate between lineages, leading to potential misestimations. Sequencing depth requirements will increase with the complexity of the sample composition and the diversity of lineages present. For samples containing multiple closely related lineages, higher sequencing depth is necessary to resolve subtle differences in genetic variation and accurately estimate lineage abundances. This is particularly important for pathogens with high mutation rates or a large number of cocirculating lineages, such as influenza, where distinguishing between lineages relies on detecting specific single nucleotide variants (SNVs) with high confidence.

Freyja Workflows

Freyja_FASTQ_PHB

Freyja measures SNV frequency and sequencing depth at each position in the genome to return an estimate of the true lineage abundances in the sample. The method uses lineage-defining "barcodes" that, for SARS-CoV-2, are derived from the UShER global phylogenetic tree as a base set for demixing. Freyja_FASTQ_PHB returns as output a TSV file that includes the lineages present and their corresponding abundances, along with other values.

The Freyja_FASTQ_PHB workflow is compatible with the multiple input data types: Ilumina Single-End, Illumina Paired-End and Oxford Nanopore. Depending on the type of input data, different input values are used.

Table 1: Freyja_FASTQ_PHB input configuration for different types of input data.

Table Columns	Illumina Paired-End	Illumina Single-End	Oxford Nanopore
read1	✅	✅	✅
read2	✅	❌	❌
ont	false	false	true

Inputs

This workflow runs on the sample level.

Illumina paired-end input dataIllumina single-end input dataONT input data

Terra Task Name	Variable	Type	Description	Default Value	Terra Status
freyja_fastq	read1	File	FASTQ file containing read1 sequences (Illumina or (ONT)		Required
freyja_fastq	reference_genome	File	The reference genome to use; should match the reference used for alignment (Wuhan-Hu-1)		Required
freyja_fastq	samplename	String	The name of the sample being analyzed		Required
freyja_fastq	freyja_lineage_metadata	File	File containing the lineage metadata; the "curated_lineages.json" file found https://github.com/andersen-lab/Freyja/tree/main/freyja/data can be used for this variable. Does not need to be provided if update_db is true or if the freyja_pathogen is provided.		Optional, Required
bwa	cpu	Int	Number of CPUs to allocate to the task	6	Optional
bwa	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
bwa	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/ivar:1.3.1-titan	Optional
bwa	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
freyja	adapt	Float	adaptive lasso penalty parameter	0.0	Optional
freyja	auto_adapt	Boolean	When set to true will use error profile to set adapt value	False	Optional
freyja	bootstrap	Boolean	Perform bootstrapping	False	Optional
freyja	confirmed_only	Boolean	Include only confirmed SARS-CoV-2 lineages	False	Optional
freyja	cpu	Int	Number of CPUs to allocate to the task	2	Optional
freyja	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
freyja	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/freyja:2.0.1	Optional
freyja	eps	Float	The minimum lineage abundance cut-off value	0.001	Optional
freyja	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
freyja	number_bootstraps	Int	The number of bootstraps to perform (only used if bootstrap = true)	100	Optional
freyja	update_db	Boolean	Updates the Freyja reference files (the usher barcodes and lineage metadata files) but will not save them as output (use Freyja_Update for that purpose). If set to true, the freyja_lineage_metadata and freyja_barcodes files are not required.	False	Optional
freyja_fastq	depth_cutoff	Int	The minimum coverage depth with which to exclude sites below this value and group identical barcodes -- THIS MAY NOT WORK FOR NON-SARS-COV-2 ORGANISMS!		Optional
freyja_fastq	freyja_barcodes	File	Custom barcode file. Does not need to be provided if update_db is true if the freyja_pathogen is provided.		Optional
freyja_fastq	freyja_pathogen	String	Pathogen to be used by Freyja	SARS-CoV-2	Optional
freyja_fastq	kraken2_target_organism	String	The organism whose abundance the user wants to check in their reads. This should be a proper taxonomic name recognized by the Kraken database.	Severe acute respiratory syndrome coronavirus 2	Optional
freyja_fastq	ont	Boolean	Indicates if the input data is derived from an ONT instrument.	False	Optional
freyja_fastq	primer_bed	File	The bed file containing the primers used when sequencing was performed		Optional
freyja_fastq	qc_check_table	File	TSV containing values to check quality control metrics		Optional
freyja_fastq	read2	File	Illumina reverse read file in FASTQ file format (compression optional)		Optional
freyja_fastq	reference_gff	File	The GFF file for reference; should match the reference used for alignment (Wuhan-Hu-1)		Optional
freyja_fastq	run_qualimap	Boolean	When set to true, will run qualimap and provide custom visuals	True	Optional
freyja_fastq	trimmomatic_min_length	Int	The minimum length cut-off when performing read cleaning	25	Optional
gene_coverage	cpu	Int	Number of CPUs to allocate to the task	2	Optional
gene_coverage	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
gene_coverage	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.15	Optional
gene_coverage	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
gene_coverage	min_depth	Int	Minimum depth for coverage	10	Optional
gene_coverage	sc2_s_gene_start	Int	Where the S gene starts	21563	Optional
gene_coverage	sc2_s_gene_stop	Int	Where the S gene stops	25384	Optional
get_fasta_genome_size	cpu	Int	Number of CPUs to allocate to the task	1	Optional
get_fasta_genome_size	disk_size	Int	Amount of storage (in GB) to allocate to the task	10	Optional
get_fasta_genome_size	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/biocontainers/seqkit:2.4.0--h9ee0642_0	Optional
get_fasta_genome_size	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
minimap2	cpu	Int	Number of CPUs to allocate to the task	2	Optional
minimap2	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
minimap2	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/minimap2:2.22	Optional
minimap2	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
minimap2	query2	File	Internal component, do not modify		Optional
nanoplot_clean	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_clean	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_clean	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_clean	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_clean	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
nanoplot_raw	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_raw	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_raw	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_raw	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_raw	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
primer_trim	cpu	Int	Number of CPUs to allocate to the task	2	Optional
primer_trim	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
primer_trim	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/ivar:1.3.1-titan	Optional
primer_trim	keep_noprimer_reads	Boolean	Include reads with no primers	True	Optional
primer_trim	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
qc_check_task	cpu	Int	Number of CPUs to allocate to the task	4	Optional
qc_check_task	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
qc_check_task	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/terra-tools:2024-08-27	Optional
qc_check_task	gambit_predicted_taxon	String	Internal component, do not modify		Optional
qc_check_task	irma_qc_table	File	Internal component, do not modify		Optional
qc_check_task	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
qualimap	cpu	Int	Number of CPUs to allocate to the task	2	Optional
qualimap	disk_size	Int	Amount of storage (in GB) to allocate to the task	50	Optional
qualimap	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/qualimap-custom-html:2.3	Optional
qualimap	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_pe	adapters	File	A FASTA file containing adapter sequences		Optional
read_QC_trim_pe	bbduk_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_pe	call_kraken	Boolean	True/False variable that determines if the Kraken2 task should be called; for non-TheiaCoV workflows, the kraken_db variable must be provided.	False	Optional
read_QC_trim_pe	call_midas	Boolean	True/False variable that determines if the MIDAS task should be called.	False	Optional
read_QC_trim_pe	fastp_args	String	Additional arguments to use with fastp	--detect_adapter_for_pe -g -5 20 -3 20	Optional
read_QC_trim_pe	kraken_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_pe	kraken_db	File	A kraken2 database to use with the kraken2 optional task. The file must be a .tar.gz kraken2 database.	gs://theiagen-public-resources-rp/reference_data/databases/kraken2/kraken2_humanGRCh38_viralRefSeq_20240828.tar.gz	Optional
read_QC_trim_pe	kraken_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_pe	kraken_memory	Int	Amount of memory/RAM (in GB) to allocate to the task		Optional
read_QC_trim_pe	midas_db	File	Database to use with MIDAS. Not required as one will be auto-selected when running the MIDAS task.	gs://theiagen-public-resources-rp/reference_data/databases/midas/midas_db_v1.2.tar.gz	Optional
read_QC_trim_pe	phix	File	The file containing the phix sequence to be used during bbduk task		Optional
read_QC_trim_pe	read_processing	String	Options: "trimmomatic" or "fastp" to indicate which read trimming module to use	trimmomatic	Optional
read_QC_trim_pe	read_qc	String	Allows the user to decide between fastq_scan (default) and fastqc for the evaluation of read quality.	fastq_scan	Optional
read_QC_trim_pe	trim_quality_min_score	Int	The minimum quality score to keep during trimming	30	Optional
read_QC_trim_pe	trim_window_size	Int	The window size to use during trimming	4	Optional
read_QC_trim_pe	trimmomatic_override_args	String	Additional arguments to pass to trimmomatic. Can be used to override all trimming parameters		Optional
sam_to_sorted_bam	cpu	Int	Number of CPUs to allocate to the task	2	Optional
sam_to_sorted_bam	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
sam_to_sorted_bam	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.17	Optional
sam_to_sorted_bam	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
sam_to_sorted_bam	min_qual	Int	Minimum quality score for reads to be included in the analysis		Optional
version_capture	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/alpine-plus-bash:3.20.0	Optional
version_capture	timezone	String	Set the time zone to get an accurate date of analysis (uses UTC by default)		Optional

Terra Task Name	Variable	Type	Description	Default Value	Terra Status
freyja_fastq	read1	File	FASTQ file containing read1 sequences (Illumina or (ONT)		Required
freyja_fastq	reference_genome	File	The reference genome to use; should match the reference used for alignment (Wuhan-Hu-1)		Required
freyja_fastq	samplename	String	The name of the sample being analyzed		Required
freyja_fastq	freyja_lineage_metadata	File	File containing the lineage metadata; the "curated_lineages.json" file found https://github.com/andersen-lab/Freyja/tree/main/freyja/data can be used for this variable. Does not need to be provided if update_db is true or if the freyja_pathogen is provided.		Optional, Required
bwa	cpu	Int	Number of CPUs to allocate to the task	6	Optional
bwa	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
bwa	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/ivar:1.3.1-titan	Optional
bwa	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
freyja	adapt	Float	adaptive lasso penalty parameter	0.0	Optional
freyja	auto_adapt	Boolean	When set to true will use error profile to set adapt value	False	Optional
freyja	bootstrap	Boolean	Perform bootstrapping	False	Optional
freyja	confirmed_only	Boolean	Include only confirmed SARS-CoV-2 lineages	False	Optional
freyja	cpu	Int	Number of CPUs to allocate to the task	2	Optional
freyja	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
freyja	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/freyja:2.0.1	Optional
freyja	eps	Float	The minimum lineage abundance cut-off value	0.001	Optional
freyja	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
freyja	number_bootstraps	Int	The number of bootstraps to perform (only used if bootstrap = true)	100	Optional
freyja	update_db	Boolean	Updates the Freyja reference files (the usher barcodes and lineage metadata files) but will not save them as output (use Freyja_Update for that purpose). If set to true, the freyja_lineage_metadata and freyja_barcodes files are not required.	False	Optional
freyja_fastq	depth_cutoff	Int	The minimum coverage depth with which to exclude sites below this value and group identical barcodes -- THIS MAY NOT WORK FOR NON-SARS-COV-2 ORGANISMS!		Optional
freyja_fastq	freyja_barcodes	File	Custom barcode file. Does not need to be provided if update_db is true if the freyja_pathogen is provided.		Optional
freyja_fastq	freyja_pathogen	String	Pathogen to be used by Freyja	SARS-CoV-2	Optional
freyja_fastq	kraken2_target_organism	String	The organism whose abundance the user wants to check in their reads. This should be a proper taxonomic name recognized by the Kraken database.	Severe acute respiratory syndrome coronavirus 2	Optional
freyja_fastq	ont	Boolean	Indicates if the input data is derived from an ONT instrument.	False	Optional
freyja_fastq	primer_bed	File	The bed file containing the primers used when sequencing was performed		Optional
freyja_fastq	qc_check_table	File	TSV containing values to check quality control metrics		Optional
freyja_fastq	read2	File	Illumina reverse read file in FASTQ file format (compression optional)		Optional
freyja_fastq	reference_gff	File	The GFF file for reference; should match the reference used for alignment (Wuhan-Hu-1)		Optional
freyja_fastq	run_qualimap	Boolean	When set to true, will run qualimap and provide custom visuals	True	Optional
freyja_fastq	trimmomatic_min_length	Int	The minimum length cut-off when performing read cleaning	25	Optional
gene_coverage	cpu	Int	Number of CPUs to allocate to the task	2	Optional
gene_coverage	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
gene_coverage	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.15	Optional
gene_coverage	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
gene_coverage	min_depth	Int	Minimum depth for coverage	10	Optional
gene_coverage	sc2_s_gene_start	Int	Where the S gene starts	21563	Optional
gene_coverage	sc2_s_gene_stop	Int	Where the S gene stops	25384	Optional
get_fasta_genome_size	cpu	Int	Number of CPUs to allocate to the task	1	Optional
get_fasta_genome_size	disk_size	Int	Amount of storage (in GB) to allocate to the task	10	Optional
get_fasta_genome_size	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/biocontainers/seqkit:2.4.0--h9ee0642_0	Optional
get_fasta_genome_size	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
minimap2	cpu	Int	Number of CPUs to allocate to the task	2	Optional
minimap2	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
minimap2	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/minimap2:2.22	Optional
minimap2	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
minimap2	query2	File	Internal component, do not modify		Optional
nanoplot_clean	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_clean	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_clean	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_clean	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_clean	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
nanoplot_raw	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_raw	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_raw	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_raw	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_raw	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
primer_trim	cpu	Int	Number of CPUs to allocate to the task	2	Optional
primer_trim	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
primer_trim	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/ivar:1.3.1-titan	Optional
primer_trim	keep_noprimer_reads	Boolean	Include reads with no primers	True	Optional
primer_trim	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
qc_check_task	cpu	Int	Number of CPUs to allocate to the task	4	Optional
qc_check_task	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
qc_check_task	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/terra-tools:2024-08-27	Optional
qc_check_task	gambit_predicted_taxon	String	Internal component, do not modify		Optional
qc_check_task	irma_qc_table	File	Internal component, do not modify		Optional
qc_check_task	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
qualimap	cpu	Int	Number of CPUs to allocate to the task	2	Optional
qualimap	disk_size	Int	Amount of storage (in GB) to allocate to the task	50	Optional
qualimap	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/qualimap-custom-html:2.3	Optional
qualimap	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_se	adapters	File	A FASTA file containing adapter sequences		Optional
read_QC_trim_se	bbduk_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_se	call_kraken	Boolean	True/False variable that determines if the Kraken2 task should be called; for non-TheiaCoV workflows, the kraken_db variable must be provided.	False	Optional
read_QC_trim_se	call_midas	Boolean	True/False variable that determines if the MIDAS task should be called.	False	Optional
read_QC_trim_se	fastp_args	String	Additional arguments to use with fastp	-g -5 20 -3 20	Optional
read_QC_trim_se	kraken_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_se	kraken_db	File	A kraken2 database to use with the kraken2 optional task. The file must be a .tar.gz kraken2 database.	gs://theiagen-public-resources-rp/reference_data/databases/kraken2/kraken2_humanGRCh38_viralRefSeq_20240828.tar.gz	Optional
read_QC_trim_se	kraken_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_se	kraken_memory	Int	Amount of memory/RAM (in GB) to allocate to the task		Optional
read_QC_trim_se	midas_db	File	Database to use with MIDAS. Not required as one will be auto-selected when running the MIDAS task.	gs://theiagen-public-resources-rp/reference_data/databases/midas/midas_db_v1.2.tar.gz	Optional
read_QC_trim_se	phix	File	The file containing the phix sequence to be used during bbduk task		Optional
read_QC_trim_se	read_processing	String	Options: "trimmomatic" or "fastp" to indicate which read trimming module to use	trimmomatic	Optional
read_QC_trim_se	read_qc	String	Allows the user to decide between fastq_scan (default) and fastqc for the evaluation of read quality.	fastq_scan	Optional
read_QC_trim_se	trim_quality_min_score	Int	The minimum quality score to keep during trimming	30	Optional
read_QC_trim_se	trim_window_size	Int	The window size to use during trimming	4	Optional
read_QC_trim_se	trimmomatic_override_args	String	Additional arguments to pass to trimmomatic. Can be used to override all trimming parameters		Optional
sam_to_sorted_bam	cpu	Int	Number of CPUs to allocate to the task	2	Optional
sam_to_sorted_bam	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
sam_to_sorted_bam	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.17	Optional
sam_to_sorted_bam	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
sam_to_sorted_bam	min_qual	Int	Minimum quality score for reads to be included in the analysis		Optional
version_capture	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/alpine-plus-bash:3.20.0	Optional
version_capture	timezone	String	Set the time zone to get an accurate date of analysis (uses UTC by default)		Optional

Terra Task Name	Variable	Type	Description	Default Value	Terra Status
freyja_fastq	read1	File	FASTQ file containing read1 sequences (Illumina or (ONT)		Required
freyja_fastq	reference_genome	File	The reference genome to use; should match the reference used for alignment (Wuhan-Hu-1)		Required
freyja_fastq	samplename	String	The name of the sample being analyzed		Required
freyja_fastq	freyja_lineage_metadata	File	File containing the lineage metadata; the "curated_lineages.json" file found https://github.com/andersen-lab/Freyja/tree/main/freyja/data can be used for this variable. Does not need to be provided if update_db is true or if the freyja_pathogen is provided.		Optional, Required
bwa	cpu	Int	Number of CPUs to allocate to the task	6	Optional
bwa	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
bwa	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/ivar:1.3.1-titan	Optional
bwa	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
freyja	adapt	Float	adaptive lasso penalty parameter	0.0	Optional
freyja	auto_adapt	Boolean	When set to true will use error profile to set adapt value	False	Optional
freyja	bootstrap	Boolean	Perform bootstrapping	False	Optional
freyja	confirmed_only	Boolean	Include only confirmed SARS-CoV-2 lineages	False	Optional
freyja	cpu	Int	Number of CPUs to allocate to the task	2	Optional
freyja	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
freyja	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/freyja:2.0.1	Optional
freyja	eps	Float	The minimum lineage abundance cut-off value	0.001	Optional
freyja	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
freyja	number_bootstraps	Int	The number of bootstraps to perform (only used if bootstrap = true)	100	Optional
freyja	update_db	Boolean	Updates the Freyja reference files (the usher barcodes and lineage metadata files) but will not save them as output (use Freyja_Update for that purpose). If set to true, the freyja_lineage_metadata and freyja_barcodes files are not required.	False	Optional
freyja_fastq	depth_cutoff	Int	The minimum coverage depth with which to exclude sites below this value and group identical barcodes -- THIS MAY NOT WORK FOR NON-SARS-COV-2 ORGANISMS!		Optional
freyja_fastq	freyja_barcodes	File	Custom barcode file. Does not need to be provided if update_db is true if the freyja_pathogen is provided.		Optional
freyja_fastq	freyja_pathogen	String	Pathogen to be used by Freyja	SARS-CoV-2	Optional
freyja_fastq	kraken2_target_organism	String	The organism whose abundance the user wants to check in their reads. This should be a proper taxonomic name recognized by the Kraken database.	Severe acute respiratory syndrome coronavirus 2	Optional
freyja_fastq	ont	Boolean	Indicates if the input data is derived from an ONT instrument.	False	Optional
freyja_fastq	primer_bed	File	The bed file containing the primers used when sequencing was performed		Optional
freyja_fastq	qc_check_table	File	TSV containing values to check quality control metrics		Optional
freyja_fastq	read2	File	Illumina reverse read file in FASTQ file format (compression optional)		Optional
freyja_fastq	reference_gff	File	The GFF file for reference; should match the reference used for alignment (Wuhan-Hu-1)		Optional
freyja_fastq	run_qualimap	Boolean	When set to true, will run qualimap and provide custom visuals	True	Optional
freyja_fastq	trimmomatic_min_length	Int	The minimum length cut-off when performing read cleaning	25	Optional
gene_coverage	cpu	Int	Number of CPUs to allocate to the task	2	Optional
gene_coverage	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
gene_coverage	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.15	Optional
gene_coverage	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
gene_coverage	min_depth	Int	Minimum depth for coverage	10	Optional
gene_coverage	sc2_s_gene_start	Int	Where the S gene starts	21563	Optional
gene_coverage	sc2_s_gene_stop	Int	Where the S gene stops	25384	Optional
get_fasta_genome_size	cpu	Int	Number of CPUs to allocate to the task	1	Optional
get_fasta_genome_size	disk_size	Int	Amount of storage (in GB) to allocate to the task	10	Optional
get_fasta_genome_size	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/biocontainers/seqkit:2.4.0--h9ee0642_0	Optional
get_fasta_genome_size	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
minimap2	cpu	Int	Number of CPUs to allocate to the task	2	Optional
minimap2	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
minimap2	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/minimap2:2.22	Optional
minimap2	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
minimap2	query2	File	Internal component, do not modify		Optional
nanoplot_clean	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_clean	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_clean	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_clean	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_clean	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
nanoplot_raw	cpu	Int	Number of CPUs to allocate to the task	4	Optional
nanoplot_raw	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
nanoplot_raw	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/nanoplot:1.40.0	Optional
nanoplot_raw	max_length	Int	The maximum length of clean reads, for which reads longer than the length specified will be hidden.	100000	Optional
nanoplot_raw	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
qc_check_task	cpu	Int	Number of CPUs to allocate to the task	4	Optional
qc_check_task	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
qc_check_task	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/terra-tools:2024-08-27	Optional
qc_check_task	gambit_predicted_taxon	String	Internal component, do not modify		Optional
qc_check_task	irma_qc_table	File	Internal component, do not modify		Optional
qc_check_task	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
qualimap	cpu	Int	Number of CPUs to allocate to the task	2	Optional
qualimap	disk_size	Int	Amount of storage (in GB) to allocate to the task	50	Optional
qualimap	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/qualimap-custom-html:2.3	Optional
qualimap	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_ont	artic_guppyplex_cpu	Int	Number of CPUs to allocate to the task	8	Optional
read_QC_trim_ont	artic_guppyplex_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	artic_guppyplex_docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/artic-ncov2019:1.3.0-medaka-1.4.3	Optional
read_QC_trim_ont	artic_guppyplex_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	16	Optional
read_QC_trim_ont	call_kraken	Boolean	True/False variable that determines if the Kraken2 task should be called; for non-TheiaCoV workflows, the kraken_db variable must be provided.	False	Optional
read_QC_trim_ont	downsampling_coverage	Float	Internal component, do not modify	150	Optional
read_QC_trim_ont	genome_length	Int	Length of the genome	5000000	Optional
read_QC_trim_ont	kraken2_recalculate_abundances_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_ont	kraken2_recalculate_abundances_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	kraken2_recalculate_abundances_docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/terra-tools:2023-08-28-v4	Optional
read_QC_trim_ont	kraken2_recalculate_abundances_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_ont	kraken_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_ont	kraken_db	File	A kraken2 database to use with the kraken2 optional task. The file must be a .tar.gz kraken2 database.	gs://theiagen-public-resources-rp/reference_data/databases/kraken2/kraken2_humanGRCh38_viralRefSeq_20240828.tar.gz	Optional
read_QC_trim_ont	kraken_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	kraken_docker_image	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/kraken2:2.1.2-no-db	Optional
read_QC_trim_ont	kraken_memory	Int	Amount of memory/RAM (in GB) to allocate to the task		Optional
read_QC_trim_ont	max_length	Int	Internal component, do not modify	700	Optional
read_QC_trim_ont	min_length	Int	Internal component, do not modify	400	Optional
read_QC_trim_ont	nanoq_cpu	Int	Number of CPUs to allocate to the task	2	Optional
read_QC_trim_ont	nanoq_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	nanoq_docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/biocontainers/nanoq:0.9.0--hec16e2b_1	Optional
read_QC_trim_ont	nanoq_max_read_length	Int	Maximum read length to use for filtering	100000	Optional
read_QC_trim_ont	nanoq_max_read_qual	Int	Maximum read quality to use for filtering	100	Optional
read_QC_trim_ont	nanoq_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
read_QC_trim_ont	nanoq_min_read_length	Int	Minimum read length to use for filtering	500	Optional
read_QC_trim_ont	nanoq_min_read_qual	Int	Minimum read quality to use for filtering	10	Optional
read_QC_trim_ont	ncbi_scrub_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_ont	ncbi_scrub_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	ncbi_scrub_docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/ncbi/sra-human-scrubber:2.2.1	Optional
read_QC_trim_ont	ncbi_scrub_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_ont	rasusa_bases	String	Explicitly set the number of bases required e.g., 4.3kb, 7Tb, 9000, 4.1MB. If this option is given, --coverage and --genome-size are ignored		Optional
read_QC_trim_ont	rasusa_cpu	Int	Number of CPUs to allocate to the task	4	Optional
read_QC_trim_ont	rasusa_disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
read_QC_trim_ont	rasusa_docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/rasusa:2.1.0	Optional
read_QC_trim_ont	rasusa_fraction_of_reads	Float	Subsample to a fraction of the reads - e.g., 0.5 samples half the reads		Optional
read_QC_trim_ont	rasusa_memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
read_QC_trim_ont	rasusa_number_of_reads	Int	Subsample to a specific number of reads		Optional
read_QC_trim_ont	rasusa_seed	Int	Random seed to use		Optional
read_QC_trim_ont	run_prefix	String	Internal component, do not modify	artic_ncov2019	Optional
sam_to_sorted_bam	cpu	Int	Number of CPUs to allocate to the task	2	Optional
sam_to_sorted_bam	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
sam_to_sorted_bam	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/samtools:1.17	Optional
sam_to_sorted_bam	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	8	Optional
sam_to_sorted_bam	min_qual	Int	Minimum quality score for reads to be included in the analysis		Optional
version_capture	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/alpine-plus-bash:3.20.0	Optional
version_capture	timezone	String	Set the time zone to get an accurate date of analysis (uses UTC by default)		Optional

Analysis Tasks

Illumina paired-end input dataIllumina single-end input dataONT input data

read_QC_trim: Read Quality Trimming, Adapter Removal, Quantification, and Identification

read_QC_trim is a sub-workflow that removes low-quality reads, low-quality regions of reads, and sequencing adapters to improve data quality. It uses a number of tasks, described below. The differences between the PE and SE versions of the read_QC_trim sub-workflow lie in the default parameters, the use of two or one input read file(s), and the different output files.

HRRT: Human Host Sequence Removal

All reads of human origin are removed, including their mates, by using NCBI's human read removal tool (HRRT).

HRRT is based on the SRA Taxonomy Analysis Tool and employs a k-mer database constructed of k-mers from Eukaryota derived from all human RefSeq records with any k-mers found in non-Eukaryota RefSeq records subtracted from the database.

NCBI-Scrub Technical Details

	Links
Task	task_ncbi_scrub.wdl
Software Source Code	HRRT on GitHub
Software Documentation	HRRT on NCBI

By default, read_processing is set to "trimmomatic". To use fastp instead, set read_processing to "fastp". These tasks are mutually exclusive.

Trimmomatic: Read Trimming (default)

Read proccessing is available via Trimmomatic by default.

Trimmomatic trims low-quality regions of Illumina paired-end or single-end reads with a sliding window (with a default window size of 4, specified with trim_window_size), cutting once the average quality within the window falls below the trimmomatic_window_quality (default of 30 for both paired-end and single-end). The read is discarded if it is trimmed below trimmomatic_min_length (default of 75 for paired-end, 25 for single-end).

Adapter trimming with Trimmomatic is disabled by default. It can be enabled by setting trimmomatic_trim_adapters=true. When enabled, Trimmomatic uses its default adapter sequences, TruSeq3-PE-2.fa (for paired-end) or TruSeq3-SE.fa (for single-end) with default adapter clipping settings equivalent to:

ILLUMINACLIP:<adapter_fasta>:2:30:10

2 = seed mismatches
30 = palindrome clip threshold
10 = simple clip threshold

Users can optionally provide a custom adapter file or modify adapter trimming parameters using the trimmomatic_adapter_fasta and trimmomatic_adapter_trim_args respectively. See the Trimmomatic adapter documentation for more details. The trimmomatic_adapter_fasta parameter should just include the path to your fasta file. The trimmomatic_adapter_trim_args parameter should only contain the colon-delimited values that comes after the adapter fasta file in the ILLUMINACLIP argument. Example usage:

trimmomatic_adapter_fasta="path/to/my_custom_adapters.fa"
trimmomatic_adapter_trim_args="2:30:10"

For more advanced configurations, there are options to override the default trimming parameters via trimmomatic_override_args. Note that when using trimmomatic_override_args, the user is responsible for specifying all desired trimming steps and their order, as the default trimming steps will be ignored. See the Trimmomatic documentation for more details on available trimming steps and their parameters.

Advanced Configuration Example Usage:

trimmomatic_override_args="LEADING:30 TRAILING:30 AVGQUAL:36 SLIDINGWINDOW:4:33 MINLEN:75"

Trimmomatic Technical Details

	Links
Task	task_trimmomatic.wdl
Software Source Code	Trimmomatic on GitHub
Software Documentation	Trimmomatic Website
Original Publication(s)	Trimmomatic: a flexible trimmer for Illumina sequence data

fastp: Read Trimming (alternative)

To activate this task, set read_processing to "fastp".

fastp trims low-quality regions of Illumina paired-end or single-end reads with a sliding window (with a default window size of 4 (10 for TheiaEuk), specified with trim_window_size), cutting once the average quality within the window falls below the trim_quality_trim_score (default of 20 for paired-end, 30 for single-end). The read is discarded if it is trimmed below trim_minlen (default of 75 bases for paired-end, 25 for single-end).

fastp also has additional default parameters and features that are not a part of trimmomatic's default configuration.

fastp default read-trimming parameters

Parameter	Explanation
-g	enables polyG tail trimming
-5 20	enables read end-trimming
-3 20	enables read end-trimming
--detect_adapter_for_pe	enables adapter-trimming only for paired-end reads

Additional arguments can be passed using the fastp_args optional parameter.

Trimmomatic and fastp Technical Details

	Links
Task	task_fastp.wdl
Software Source Code	fastp on GitHub
Software Documentation	fastp on GitHub
Original Publication(s)	fastp: an ultra-fast all-in-one FASTQ preprocessor

BBDuk: Adapter Trimming and PhiX Removal

Adapters are manufactured oligonucleotide sequences attached to DNA fragments during the library preparation process. In Illumina sequencing, these adapter sequences are required for attaching reads to flow cells. You can read more about Illumina adapters here. For genome analysis, it's important to remove these sequences since they're not actually from your sample. If you don't remove them, the downstream analysis may be affected.

By default, the bbduk task will:

• Repair disordered read pairs (if they exist) so that the first read in file 1 is the same mate of the first read in file2. See the Repair Guide from the BBTools package.

• Remove PhiX contamination by filtering out all reads that have a 31-mer match to PhiX. PhiX is a viral genome that is often used as a control in Illumina sequencing runs. Removing PhiX sequences helps to ensure that the data reflects only the target organism's genome. By default this task uses the built-in PhiX reference fasta provided with BBTools (see here), but a custom PhiX reference can be provided via the phix_fasta input parameter.

• Trim adapters with BBDuk ("Bestus Bioinformaticus" Decontamination Using Kmers). By default this uses the built-in adapter sequences provided with BBTools (see here). If you have custom adapter sequences specific to your library preparation, you can provide them via the adapters_fasta input parameter.

BBDuk Technical Details

	Links
Task	task_bbduk.wdl
Software Source Code	BBMap on SourceForge
Software Documentation	BBDuk Guide (archived)

By default, read_qc is set to "fastq_scan". To use fastqc instead, set read_qc to "fastqc". These tasks are mutually exclusive.

fastq-scan: Read Quantification (default)

Read quantification is available via fastq-scan by default.

fastq-scan quantifies the forward and reverse reads in FASTQ files. For paired-end data, it also provide the total number of read pairs. This task is run once with raw reads as input and once with clean reads as input. If QC has been performed correctly, you should expect fewer clean reads than raw reads.

fastq-scan Technical Details

	Links
Task	task_fastq_scan.wdl
Software Source Code	fastq-scan on GitHub
Software Documentation	fastq-scan on GitHub

FastQC: Read Quantification (alternative)

To activate this task, set read_qc to "fastqc".

FastQC quantifies the forward and reverse reads in FASTQ files. For paired-end data, it also provide the total number of read pairs. This task is run once with raw reads as input and once with clean reads as input. If QC has been performed correctly, you should expect fewer clean reads than raw reads.

This tool also provides a graphical visualization of the read quality.

FastQC Technical Details

	Links
Task	task_fastqc.wdl
Software Source Code	FastQC on Github
Software Documentation	FastQC Website

read_QC_trim Technical Details

	Links
Subworkflow	wf_read_QC_trim_pe.wdl wf_read_QC_trim_se.wdl

bwa Details

This task aligns the cleaned short reads (Illumina) to the reference genome provided by the user.

BWA Technical Details

	Links
Task	task_bwa.wdl
Software Source Code	BWA on GitHub
Software Documentation	BWA Documentation
Original Publication(s)	Fast and accurate short read alignment with Burrows-Wheeler transform

primer_trim Details

This task trims the primer sequences from the aligned bam file with iVar. The optional input, keep_noprimer_reads, does not have to be modified.

Primer Trim Technical Details

	Links
Task	task_ivar_primer_trim.wdl
Software Source Code	https://github.com/andersen-lab/ivar
Software Documentation	https://andersen-lab.github.io/ivar/html/manualpage.html
Original Publication(s)	An amplicon-based sequencing framework for accurately measuring intrahost virus diversity using PrimalSeq and iVar

QualiMap: BAM File Quality Assessment

QualiMap evaluates the quality of alignment data in BAM files by computing various metrics including coverage distribution, mapping quality, GC content, and various metrics analyzed across the reference. It provides comprehensive quality control reports for next-generation sequencing alignment data.

This task generates both standard QualiMap reports and custom interactive HTML visualizations for genome coverage and mapping quality across the reference sequence. The results are bundled into a compressed archive for easy download and review, especially since for the QualiMap report to render the pngs correctly, it needs to preserve directory structure.

QualiMap Technical Details

	Links
Task	task_qualimap.wdl
Software Source Code	QualiMap on Bitbucket
Software Documentation	QualiMap Documentation
Original Publication(s)	QualiMap: evaluating next-generation sequencing alignment data

qc_check: Check QC Metrics Against User-Defined Thresholds (optional)

To activate this task, provide a qc_check_table as input.

The qc_check task compares generated QC metrics against user-defined thresholds for each metric. This task will run if the user provides a qc_check_table TSV file. If all QC metrics meet the threshold, the qc_check output variable will read QC_PASS. Otherwise, the output will read QC_NA if the task could not proceed or QC_ALERT followed by a string indicating what metric failed.

Formatting the qc_check_table.tsv

• The first column of the qc_check_table lists the organism that the task will assess and the header of this column must be "taxon".
• Each subsequent column indicates a QC metric and lists a threshold for each organism that will be checked. The column names must exactly match expected values, so we highly recommend copy and pasting the header from the template file below as a starting place.

Template qc_check_table.tsv files

• Freyja_FASTQ: freyja_qc_check_template.tsv

Example Purposes Only

The QC threshold values shown in the file above are for example purposes only and should not be presumed to be sufficient for every dataset.

qc_check Technical Details

	Links
Task	task_qc_check_phb.wdl

read_QC_trim: Read Quality Trimming, Adapter Removal, Quantification, and Identification

read_QC_trim is a sub-workflow that removes low-quality reads, low-quality regions of reads, and sequencing adapters to improve data quality. It uses a number of tasks, described below. The differences between the PE and SE versions of the read_QC_trim sub-workflow lie in the default parameters, the use of two or one input read file(s), and the different output files.

HRRT: Human Host Sequence Removal

All reads of human origin are removed, including their mates, by using NCBI's human read removal tool (HRRT).

HRRT is based on the SRA Taxonomy Analysis Tool and employs a k-mer database constructed of k-mers from Eukaryota derived from all human RefSeq records with any k-mers found in non-Eukaryota RefSeq records subtracted from the database.

NCBI-Scrub Technical Details

	Links
Task	task_ncbi_scrub.wdl
Software Source Code	HRRT on GitHub
Software Documentation	HRRT on NCBI

By default, read_processing is set to "trimmomatic". To use fastp instead, set read_processing to "fastp". These tasks are mutually exclusive.

Trimmomatic: Read Trimming (default)

Read proccessing is available via Trimmomatic by default.

Trimmomatic trims low-quality regions of Illumina paired-end or single-end reads with a sliding window (with a default window size of 4, specified with trim_window_size), cutting once the average quality within the window falls below the trimmomatic_window_quality (default of 30 for both paired-end and single-end). The read is discarded if it is trimmed below trimmomatic_min_length (default of 75 for paired-end, 25 for single-end).

Adapter trimming with Trimmomatic is disabled by default. It can be enabled by setting trimmomatic_trim_adapters=true. When enabled, Trimmomatic uses its default adapter sequences, TruSeq3-PE-2.fa (for paired-end) or TruSeq3-SE.fa (for single-end) with default adapter clipping settings equivalent to:

ILLUMINACLIP:<adapter_fasta>:2:30:10

2 = seed mismatches
30 = palindrome clip threshold
10 = simple clip threshold

Users can optionally provide a custom adapter file or modify adapter trimming parameters using the trimmomatic_adapter_fasta and trimmomatic_adapter_trim_args respectively. See the Trimmomatic adapter documentation for more details. The trimmomatic_adapter_fasta parameter should just include the path to your fasta file. The trimmomatic_adapter_trim_args parameter should only contain the colon-delimited values that comes after the adapter fasta file in the ILLUMINACLIP argument. Example usage:

trimmomatic_adapter_fasta="path/to/my_custom_adapters.fa"
trimmomatic_adapter_trim_args="2:30:10"

For more advanced configurations, there are options to override the default trimming parameters via trimmomatic_override_args. Note that when using trimmomatic_override_args, the user is responsible for specifying all desired trimming steps and their order, as the default trimming steps will be ignored. See the Trimmomatic documentation for more details on available trimming steps and their parameters.

Advanced Configuration Example Usage:

trimmomatic_override_args="LEADING:30 TRAILING:30 AVGQUAL:36 SLIDINGWINDOW:4:33 MINLEN:75"

Trimmomatic Technical Details

	Links
Task	task_trimmomatic.wdl
Software Source Code	Trimmomatic on GitHub
Software Documentation	Trimmomatic Website
Original Publication(s)	Trimmomatic: a flexible trimmer for Illumina sequence data

fastp: Read Trimming (alternative)

To activate this task, set read_processing to "fastp".

fastp trims low-quality regions of Illumina paired-end or single-end reads with a sliding window (with a default window size of 4 (10 for TheiaEuk), specified with trim_window_size), cutting once the average quality within the window falls below the trim_quality_trim_score (default of 20 for paired-end, 30 for single-end). The read is discarded if it is trimmed below trim_minlen (default of 75 bases for paired-end, 25 for single-end).

fastp also has additional default parameters and features that are not a part of trimmomatic's default configuration.

fastp default read-trimming parameters

Parameter	Explanation
-g	enables polyG tail trimming
-5 20	enables read end-trimming
-3 20	enables read end-trimming
--detect_adapter_for_pe	enables adapter-trimming only for paired-end reads

Additional arguments can be passed using the fastp_args optional parameter.

Trimmomatic and fastp Technical Details

	Links
Task	task_fastp.wdl
Software Source Code	fastp on GitHub
Software Documentation	fastp on GitHub
Original Publication(s)	fastp: an ultra-fast all-in-one FASTQ preprocessor

BBDuk: Adapter Trimming and PhiX Removal

Adapters are manufactured oligonucleotide sequences attached to DNA fragments during the library preparation process. In Illumina sequencing, these adapter sequences are required for attaching reads to flow cells. You can read more about Illumina adapters here. For genome analysis, it's important to remove these sequences since they're not actually from your sample. If you don't remove them, the downstream analysis may be affected.

By default, the bbduk task will:

• Repair disordered read pairs (if they exist) so that the first read in file 1 is the same mate of the first read in file2. See the Repair Guide from the BBTools package.

• Remove PhiX contamination by filtering out all reads that have a 31-mer match to PhiX. PhiX is a viral genome that is often used as a control in Illumina sequencing runs. Removing PhiX sequences helps to ensure that the data reflects only the target organism's genome. By default this task uses the built-in PhiX reference fasta provided with BBTools (see here), but a custom PhiX reference can be provided via the phix_fasta input parameter.

• Trim adapters with BBDuk ("Bestus Bioinformaticus" Decontamination Using Kmers). By default this uses the built-in adapter sequences provided with BBTools (see here). If you have custom adapter sequences specific to your library preparation, you can provide them via the adapters_fasta input parameter.

BBDuk Technical Details

	Links
Task	task_bbduk.wdl
Software Source Code	BBMap on SourceForge
Software Documentation	BBDuk Guide (archived)

By default, read_qc is set to "fastq_scan". To use fastqc instead, set read_qc to "fastqc". These tasks are mutually exclusive.

fastq-scan: Read Quantification (default)

Read quantification is available via fastq-scan by default.

fastq-scan quantifies the forward and reverse reads in FASTQ files. For paired-end data, it also provide the total number of read pairs. This task is run once with raw reads as input and once with clean reads as input. If QC has been performed correctly, you should expect fewer clean reads than raw reads.

fastq-scan Technical Details

	Links
Task	task_fastq_scan.wdl
Software Source Code	fastq-scan on GitHub
Software Documentation	fastq-scan on GitHub

FastQC: Read Quantification (alternative)

To activate this task, set read_qc to "fastqc".

FastQC quantifies the forward and reverse reads in FASTQ files. For paired-end data, it also provide the total number of read pairs. This task is run once with raw reads as input and once with clean reads as input. If QC has been performed correctly, you should expect fewer clean reads than raw reads.

This tool also provides a graphical visualization of the read quality.

FastQC Technical Details

	Links
Task	task_fastqc.wdl
Software Source Code	FastQC on Github
Software Documentation	FastQC Website

read_QC_trim Technical Details

	Links
Subworkflow	wf_read_QC_trim_pe.wdl wf_read_QC_trim_se.wdl

bwa Details

This task aligns the cleaned short reads (Illumina) to the reference genome provided by the user.

BWA Technical Details

	Links
Task	task_bwa.wdl
Software Source Code	BWA on GitHub
Software Documentation	BWA Documentation
Original Publication(s)	Fast and accurate short read alignment with Burrows-Wheeler transform

primer_trim Details

This task trims the primer sequences from the aligned bam file with iVar. The optional input, keep_noprimer_reads, does not have to be modified.

Primer Trim Technical Details

	Links
Task	task_ivar_primer_trim.wdl
Software Source Code	https://github.com/andersen-lab/ivar
Software Documentation	https://andersen-lab.github.io/ivar/html/manualpage.html
Original Publication(s)	An amplicon-based sequencing framework for accurately measuring intrahost virus diversity using PrimalSeq and iVar

QualiMap: BAM File Quality Assessment

QualiMap evaluates the quality of alignment data in BAM files by computing various metrics including coverage distribution, mapping quality, GC content, and various metrics analyzed across the reference. It provides comprehensive quality control reports for next-generation sequencing alignment data.

This task generates both standard QualiMap reports and custom interactive HTML visualizations for genome coverage and mapping quality across the reference sequence. The results are bundled into a compressed archive for easy download and review, especially since for the QualiMap report to render the pngs correctly, it needs to preserve directory structure.

QualiMap Technical Details

	Links
Task	task_qualimap.wdl
Software Source Code	QualiMap on Bitbucket
Software Documentation	QualiMap Documentation
Original Publication(s)	QualiMap: evaluating next-generation sequencing alignment data

qc_check: Check QC Metrics Against User-Defined Thresholds (optional)

To activate this task, provide a qc_check_table as input.

The qc_check task compares generated QC metrics against user-defined thresholds for each metric. This task will run if the user provides a qc_check_table TSV file. If all QC metrics meet the threshold, the qc_check output variable will read QC_PASS. Otherwise, the output will read QC_NA if the task could not proceed or QC_ALERT followed by a string indicating what metric failed.

Formatting the qc_check_table.tsv

• The first column of the qc_check_table lists the organism that the task will assess and the header of this column must be "taxon".
• Each subsequent column indicates a QC metric and lists a threshold for each organism that will be checked. The column names must exactly match expected values, so we highly recommend copy and pasting the header from the template file below as a starting place.

Template qc_check_table.tsv files

• Freyja_FASTQ: freyja_qc_check_template.tsv

Example Purposes Only

The QC threshold values shown in the file above are for example purposes only and should not be presumed to be sufficient for every dataset.

qc_check Technical Details

	Links
Task	task_qc_check_phb.wdl

read_QC_trim_ont: Read Quality Trimming, Quantification, and Identification

read_QC_trim_ont is a sub-workflow that filters low-quality reads and trims low-quality regions of reads. It uses several tasks, described below.

HRRT: Human Host Sequence Removal

All reads of human origin are removed, including their mates, by using NCBI's human read removal tool (HRRT).

HRRT is based on the SRA Taxonomy Analysis Tool and employs a k-mer database constructed of k-mers from Eukaryota derived from all human RefSeq records with any k-mers found in non-Eukaryota RefSeq records subtracted from the database.

NCBI-Scrub Technical Details

	Links
Task	task_ncbi_scrub.wdl
Software Source Code	HRRT on GitHub
Software Documentation	HRRT on NCBI

artic_guppyplex: Read Filtering

Reads are filtered by length with artic_guppyplex, which is a part of the ARTIC protocol. Since TheiaCoV was developed primarily for amplicon-based viral sequencing, this task is included to remove chimeric reads that are either too short or too long.

artic_guppyplex Technical Details

	Links
Task	task_artic_guppyplex.wdl
Software Source Code	ARTIC on GitHub
Software Documentation	ARTIC Documentation

Kraken2: Read Identification

Kraken2 is a bioinformatics tool originally designed for metagenomic applications. It has additionally proven valuable for validating taxonomic assignments and checking contamination of single-species (e.g. bacterial isolate, eukaryotic isolate, viral isolate, etc.) whole genome sequence data.

Kraken2 is run on both the raw and clean reads.

Database-dependent

This workflow automatically uses a viral-specific Kraken2 database. This database was generated in-house from RefSeq's viral sequence collection and human genome GRCh38. It's available at gs://theiagen-public-resources-rp/reference_data/databases/kraken2/kraken2_humanGRCh38_viralRefSeq_20240828.tar.gz.

Kraken2 Technical Details

	Links
Task	task_kraken2.wdl
Software Source Code	Kraken2 on GitHub
Software Documentation	Kraken2 Documentation
Original Publication(s)	Improved metagenomic analysis with Kraken 2

NanoPlot: Read Quantification

NanoPlot is used for the determination of mean quality scores, read lengths, and number of reads. This task is run once with raw reads as input and once with clean reads as input. If QC has been performed correctly, you should expect fewer clean reads than raw reads.

While this task currently is run outside of the read_QC_trim_ont workflow, it is being included here as it calculates statistics on the read data. This is done so that the actual assembly genome lengths can be used (if an estimated genome length is not provided by the user) to ensure the estimated coverage statistics are accurate.

NanoPlot Technical Details

	Links
Task	task_nanoplot.wdl
Software Source Code	NanoPlot on GitHub
Software Documentation	NanoPlot Documentation
Original Publication(s)	NanoPack2: population-scale evaluation of long-read sequencing data

read_QC_trim_ont Technical Details

	Links
Subworkflow	wf_read_QC_trim_ont.wdl

minimap2: Read Alignment Details

minimap2 is a popular aligner that is used to align reads (or assemblies) to an assembly file. In minimap2, "modes" are a group of preset options.

The mode used in this task is map-ont which is the default mode for long reads and indicates that long reads of ~10% error rates should be aligned to the reference genome. The output file is in SAM format.

For more information regarding modes and the available options for minimap2, please see the minimap2 manpage

minimap2 Technical Details

	Links
Task	task_minimap2.wdl
Software Source Code	minimap2 on GitHub
Software Documentation	minimap2
Original Publication(s)	Minimap2: pairwise alignment for nucleotide sequences

QualiMap: BAM File Quality Assessment

QualiMap evaluates the quality of alignment data in BAM files by computing various metrics including coverage distribution, mapping quality, GC content, and various metrics analyzed across the reference. It provides comprehensive quality control reports for next-generation sequencing alignment data.

This task generates both standard QualiMap reports and custom interactive HTML visualizations for genome coverage and mapping quality across the reference sequence. The results are bundled into a compressed archive for easy download and review, especially since for the QualiMap report to render the pngs correctly, it needs to preserve directory structure.

QualiMap Technical Details

	Links
Task	task_qualimap.wdl
Software Source Code	QualiMap on Bitbucket
Software Documentation	QualiMap Documentation
Original Publication(s)	QualiMap: evaluating next-generation sequencing alignment data

qc_check: Check QC Metrics Against User-Defined Thresholds (optional)

To activate this task, provide a qc_check_table as input.

The qc_check task compares generated QC metrics against user-defined thresholds for each metric. This task will run if the user provides a qc_check_table TSV file. If all QC metrics meet the threshold, the qc_check output variable will read QC_PASS. Otherwise, the output will read QC_NA if the task could not proceed or QC_ALERT followed by a string indicating what metric failed.

Formatting the qc_check_table.tsv

• The first column of the qc_check_table lists the organism that the task will assess and the header of this column must be "taxon".
• Each subsequent column indicates a QC metric and lists a threshold for each organism that will be checked. The column names must exactly match expected values, so we highly recommend copy and pasting the header from the template file below as a starting place.

Template qc_check_table.tsv files

• Freyja_FASTQ: freyja_qc_check_template.tsv

Example Purposes Only

The QC threshold values shown in the file above are for example purposes only and should not be presumed to be sufficient for every dataset.

qc_check Technical Details

	Links
Task	task_qc_check_phb.wdl

freyja Details

The Freyja task will call variants and capture sequencing depth information to identify the relative abundance of lineages present. Optionally, if bootstrap is set to true, bootstrapping will be performed. After the optional bootstrapping step, the variants are demixed.

Freyja Technical Details

	Links
Task	task_freyja_one_sample.wdl
Software Source Code	https://github.com/andersen-lab/Freyja
Software Documentation	https://andersen-lab.github.io/Freyja/index.html#

Outputs

The main output file used in subsequent Freyja workflows is found under the freyja_demixed column. This TSV file takes on the following format:

	sample name
summarized	[('Delta', 0.65), ('Other', 0.25), ('Alpha', 0.1')]
lineages	['B.1.617.2' 'B.1.2' 'AY.6' 'Q.3']
abundances	"[0.5 0.25 0.15 0.1]"
resid	3.14159
coverage	95.8

• The summarized array denotes a sum of all lineage abundances in a particular WHO designation (i.e. B.1.617.2 and AY.6 abundances are summed in the above example), otherwise they are grouped into "Other".
• The lineage array lists the identified lineages in descending order
• The abundances array contains the corresponding abundances estimates.
• The value of resid corresponds to the residual of the weighted least absolute deviation problem used to estimate lineage abundances.
• The coverage value provides the 10x coverage estimate (percent of sites with 10 or greater reads)

Click "Ignore empty outputs"

When running the Freyja_FASTQ_PHB workflow, it is recommended to select the "Ignore empty outputs" option in the Terra UI. This will hide the output columns that will not be generated for your input data type.

Illumina paired-end output dataIllumina single-end output dataONT output data

Variable	Type	Description
aligned_bai	String	Index companion file to the bam file generated during the consensus assembly process
aligned_bam	String	Sorted BAM file containing the alignments of reads to the reference genome
alignment_method	String	The method used to generate the alignment
bbduk_docker	String	The Docker image for bbduk, which was used to remove the adapters from the sequences
bwa_version	String	Version of BWA software used
est_percent_gene_coverage_tsv	File	Percent coverage for each gene in the organism being analyzed (depending on the organism input)
fastp_docker	String	Docker image used for fastp
fastp_html_report	String	The HTML report made with fastp
fastp_json_report	String	The JSON report made with fastp
fastp_version	String	The version of fastp used
fastq_scan_clean1_json	String	The JSON file output from fastq-scan containing summary stats about clean forward read quality and length
fastq_scan_clean2_json	File	The JSON file output from fastq-scan containing summary stats about clean reverse read quality and length
fastq_scan_num_reads_clean1	String	The number of forward reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean2	Int	The number of reverse reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean_pairs	String	The number of read pairs after cleaning as calculated by fastq_scan
fastq_scan_num_reads_raw1	String	The number of input forward reads as calculated by fastq_scan
fastq_scan_num_reads_raw2	Int	The number of input reserve reads as calculated by fastq_scan
fastq_scan_num_reads_raw_pairs	String	The number of input read pairs as calculated by fastq_scan
fastq_scan_raw1_json	String	The JSON file output from fastq-scan containing summary stats about raw forward read quality and length
fastq_scan_raw2_json	File	The JSON file output from fastq-scan containing summary stats about raw reverse read quality and length
fastq_scan_version	String	The version of fastq_scan
fastqc_clean1_html	String	An HTML file that provides a graphical visualization of clean forward read quality from fastqc to open in an internet browser
fastqc_clean2_html	File	An HTML file that provides a graphical visualization of clean reverse read quality from fastqc to open in an internet browser
fastqc_docker	String	The Docker container used for fastqc
fastqc_num_reads_clean1	String	The number of forward reads after cleaning by fastqc
fastqc_num_reads_clean2	Int	The number of reverse reads after cleaning by fastqc
fastqc_num_reads_clean_pairs	String	The number of read pairs after cleaning by fastqc
fastqc_num_reads_raw1	String	The number of input forward reads by fastqc before cleaning
fastqc_num_reads_raw2	Int	The number of input reverse reads by fastqc before cleaning
fastqc_num_reads_raw_pairs	String	The number of input read pairs by fastqc before cleaning
fastqc_raw1_html	String	An HTML file that provides a graphical visualization of raw forward read quality from fastqc to open in an internet browser
fastqc_raw2_html	File	An HTML file that provides a graphical visualization of raw reverse read quality from fastqc to open in an internet browser
fastqc_version	String	Version of fastqc software used
freyja_abundances	String	Abundances estimates identified by Freyja and parsed from freyja_demixed file
freyja_barcode_file	String	Barcode file used with Freyja
freyja_barcode_version	String	Name of barcode file used, or the date if update_db is true
freyja_bootstrap_lineages	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each lineage
freyja_bootstrap_lineages_pdf	String	A boxplot of the bootstrap lineages CSV file
freyja_bootstrap_summary	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each WHO designated VOI/VOC
freyja_bootstrap_summary_pdf	String	A boxplot of the bootstrap summary CSV file
freyja_coverage	Float	Coverage identified by Freyja and parsed from freyja_demixed file
freyja_demixed	File	The main output TSV; see the section directly above this table for an explanation
freyja_demixed_parsed	File	Parsed freyja_demixed file, containing the same information, for easy result concatenation
freyja_depths	File	A TSV listing the depth of every position
freyja_fastq_wf_analysis_date	String	Date of analysis
freyja_fastq_wf_version	String	The version of the Public Health Bioinformatics (PHB) repository used
freyja_lineage_metadata_file	String	Metadata file for lineages identified by Freyja
freyja_lineages	String	Lineages in descending order identified by Freyja and parsed from freyja_demixed file
freyja_metadata_version	String	Name of lineage metadata file used, or the date if update_db is true
freyja_resid	String	Residual of the weighted least absolute deviation problem used to estimate lineage abundances identified by Freyja and parsed from freyja_demixed file
freyja_summarized	String	Sum of all lineage abundances in a particular WHO designation identified by Freyja and parsed from freyja_demixed file
freyja_variants	File	The TSV file containing the variants identified by Freyja
freyja_version	String	version of Freyja used
ivar_version_primtrim	String	Version of iVar for running the iVar trim command
kraken_human	Float	Percent of human read data detected using the Kraken2 software
kraken_human_dehosted	Float	Percent of human read data detected using the Kraken2 software after host removal
kraken_report	String	Full Kraken report
kraken_report_dehosted	File	Full Kraken report after host removal
kraken_sc2	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software
kraken_sc2_dehosted	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software after host removal
kraken_version	String	Version of Kraken software used
minimap2_docker	String	The Docker image of minimap2
minimap2_version	String	The version of minimap2
nanoplot_html_clean	File	An HTML report describing the clean reads
nanoplot_html_raw	File	An HTML report describing the raw reads
nanoplot_num_reads_clean1	Int	Number of clean reads
nanoplot_num_reads_raw1	Int	Number of raw reads
nanoplot_r1_est_coverage_clean	Float	Estimated coverage on the clean reads by nanoplot
nanoplot_r1_est_coverage_raw	Float	Estimated coverage on the raw reads by nanoplot
nanoplot_r1_mean_q_clean	Float	Mean quality score of clean forward reads
nanoplot_r1_mean_q_raw	Float	Mean quality score of raw forward reads
nanoplot_r1_mean_readlength_clean	Float	Mean read length of clean forward reads
nanoplot_r1_mean_readlength_raw	Float	Mean read length of raw forward reads
nanoplot_r1_median_q_clean	Float	Median quality score of clean forward reads
nanoplot_r1_median_q_raw	Float	Median quality score of raw forward reads
nanoplot_r1_median_readlength_clean	Float	Median read length of clean forward reads
nanoplot_r1_median_readlength_raw	Float	Median read length of raw forward reads
nanoplot_r1_n50_clean	Float	N50 of clean forward reads
nanoplot_r1_n50_raw	Float	N50 of raw forward reads
nanoplot_r1_stdev_readlength_clean	Float	Standard deviation read length of clean forward reads
nanoplot_r1_stdev_readlength_raw	Float	Standard deviation read length of raw forward reads
nanoplot_tsv_clean	File	A TSV report describing the clean reads
nanoplot_tsv_raw	File	A TSV report describing the raw reads
nanoq_version	String	Version of nanoq used in analysis
primer_bed_name	String	Name of the primer bed files used for primer trimming
primer_trimmed_read_percent	Float	Percentage of read data with primers trimmed as determined by iVar trim
qc_check	String	A string that indicates whether or not the sample passes a set of pre-determined and user-provided QC thresholds
qc_standard	File	The file used in the QC Check task containing the QC thresholds.
qualimap_coverage_plots_html	File	Interactive HTML Plots of Coverage Across the Genome
qualimap_docker	String	Qualimap docker image used
qualimap_reports_bundle	File	Zipped bundle of Qualimap reports and plots
qualimap_version	String	Version of Qualimap used
read1_clean	File	Forward read file after quality trimming and adapter removal
read1_dehosted	File	The dehosted forward reads file; suggested read file for SRA submission
read2_clean	File	Reverse read file after quality trimming and adapter removal
read2_dehosted	File	The dehosted reverse reads file; suggested read file for SRA submission
samtools_version	String	The version of SAMtools used to sort and index the alignment file
samtools_version_primtrim	String	The version of SAMtools used to create the pileup before running iVar trim
sc2_s_gene_mean_coverage	Float	Mean read depth for the S gene in SARS-CoV-2
sc2_s_gene_percent_coverage	Float	Percent coverage of the S gene in SARS-CoV-2
trimmomatic_docker	String	The docker image used for the trimmomatic module in this workflow
trimmomatic_version	String	The version of Trimmomatic used

Variable	Type	Description
aligned_bai	String	Index companion file to the bam file generated during the consensus assembly process
aligned_bam	String	Sorted BAM file containing the alignments of reads to the reference genome
alignment_method	String	The method used to generate the alignment
bbduk_docker	String	The Docker image for bbduk, which was used to remove the adapters from the sequences
bwa_version	String	Version of BWA software used
est_percent_gene_coverage_tsv	File	Percent coverage for each gene in the organism being analyzed (depending on the organism input)
fastp_docker	String	Docker image used for fastp
fastp_html_report	String	The HTML report made with fastp
fastp_json_report	String	The JSON report made with fastp
fastp_version	String	The version of fastp used
fastq_scan_clean1_json	String	The JSON file output from fastq-scan containing summary stats about clean forward read quality and length
fastq_scan_clean2_json	File	The JSON file output from fastq-scan containing summary stats about clean reverse read quality and length
fastq_scan_num_reads_clean1	String	The number of forward reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean2	Int	The number of reverse reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean_pairs	String	The number of read pairs after cleaning as calculated by fastq_scan
fastq_scan_num_reads_raw1	String	The number of input forward reads as calculated by fastq_scan
fastq_scan_num_reads_raw2	Int	The number of input reserve reads as calculated by fastq_scan
fastq_scan_num_reads_raw_pairs	String	The number of input read pairs as calculated by fastq_scan
fastq_scan_raw1_json	String	The JSON file output from fastq-scan containing summary stats about raw forward read quality and length
fastq_scan_raw2_json	File	The JSON file output from fastq-scan containing summary stats about raw reverse read quality and length
fastq_scan_version	String	The version of fastq_scan
fastqc_clean1_html	String	An HTML file that provides a graphical visualization of clean forward read quality from fastqc to open in an internet browser
fastqc_clean2_html	File	An HTML file that provides a graphical visualization of clean reverse read quality from fastqc to open in an internet browser
fastqc_docker	String	The Docker container used for fastqc
fastqc_num_reads_clean1	String	The number of forward reads after cleaning by fastqc
fastqc_num_reads_clean2	Int	The number of reverse reads after cleaning by fastqc
fastqc_num_reads_clean_pairs	String	The number of read pairs after cleaning by fastqc
fastqc_num_reads_raw1	String	The number of input forward reads by fastqc before cleaning
fastqc_num_reads_raw2	Int	The number of input reverse reads by fastqc before cleaning
fastqc_num_reads_raw_pairs	String	The number of input read pairs by fastqc before cleaning
fastqc_raw1_html	String	An HTML file that provides a graphical visualization of raw forward read quality from fastqc to open in an internet browser
fastqc_raw2_html	File	An HTML file that provides a graphical visualization of raw reverse read quality from fastqc to open in an internet browser
fastqc_version	String	Version of fastqc software used
freyja_abundances	String	Abundances estimates identified by Freyja and parsed from freyja_demixed file
freyja_barcode_file	String	Barcode file used with Freyja
freyja_barcode_version	String	Name of barcode file used, or the date if update_db is true
freyja_bootstrap_lineages	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each lineage
freyja_bootstrap_lineages_pdf	String	A boxplot of the bootstrap lineages CSV file
freyja_bootstrap_summary	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each WHO designated VOI/VOC
freyja_bootstrap_summary_pdf	String	A boxplot of the bootstrap summary CSV file
freyja_coverage	Float	Coverage identified by Freyja and parsed from freyja_demixed file
freyja_demixed	File	The main output TSV; see the section directly above this table for an explanation
freyja_demixed_parsed	File	Parsed freyja_demixed file, containing the same information, for easy result concatenation
freyja_depths	File	A TSV listing the depth of every position
freyja_fastq_wf_analysis_date	String	Date of analysis
freyja_fastq_wf_version	String	The version of the Public Health Bioinformatics (PHB) repository used
freyja_lineage_metadata_file	String	Metadata file for lineages identified by Freyja
freyja_lineages	String	Lineages in descending order identified by Freyja and parsed from freyja_demixed file
freyja_metadata_version	String	Name of lineage metadata file used, or the date if update_db is true
freyja_resid	String	Residual of the weighted least absolute deviation problem used to estimate lineage abundances identified by Freyja and parsed from freyja_demixed file
freyja_summarized	String	Sum of all lineage abundances in a particular WHO designation identified by Freyja and parsed from freyja_demixed file
freyja_variants	File	The TSV file containing the variants identified by Freyja
freyja_version	String	version of Freyja used
ivar_version_primtrim	String	Version of iVar for running the iVar trim command
kraken_human	Float	Percent of human read data detected using the Kraken2 software
kraken_human_dehosted	Float	Percent of human read data detected using the Kraken2 software after host removal
kraken_report	String	Full Kraken report
kraken_report_dehosted	File	Full Kraken report after host removal
kraken_sc2	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software
kraken_sc2_dehosted	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software after host removal
kraken_version	String	Version of Kraken software used
minimap2_docker	String	The Docker image of minimap2
minimap2_version	String	The version of minimap2
nanoplot_html_clean	File	An HTML report describing the clean reads
nanoplot_html_raw	File	An HTML report describing the raw reads
nanoplot_num_reads_clean1	Int	Number of clean reads
nanoplot_num_reads_raw1	Int	Number of raw reads
nanoplot_r1_est_coverage_clean	Float	Estimated coverage on the clean reads by nanoplot
nanoplot_r1_est_coverage_raw	Float	Estimated coverage on the raw reads by nanoplot
nanoplot_r1_mean_q_clean	Float	Mean quality score of clean forward reads
nanoplot_r1_mean_q_raw	Float	Mean quality score of raw forward reads
nanoplot_r1_mean_readlength_clean	Float	Mean read length of clean forward reads
nanoplot_r1_mean_readlength_raw	Float	Mean read length of raw forward reads
nanoplot_r1_median_q_clean	Float	Median quality score of clean forward reads
nanoplot_r1_median_q_raw	Float	Median quality score of raw forward reads
nanoplot_r1_median_readlength_clean	Float	Median read length of clean forward reads
nanoplot_r1_median_readlength_raw	Float	Median read length of raw forward reads
nanoplot_r1_n50_clean	Float	N50 of clean forward reads
nanoplot_r1_n50_raw	Float	N50 of raw forward reads
nanoplot_r1_stdev_readlength_clean	Float	Standard deviation read length of clean forward reads
nanoplot_r1_stdev_readlength_raw	Float	Standard deviation read length of raw forward reads
nanoplot_tsv_clean	File	A TSV report describing the clean reads
nanoplot_tsv_raw	File	A TSV report describing the raw reads
nanoq_version	String	Version of nanoq used in analysis
primer_bed_name	String	Name of the primer bed files used for primer trimming
primer_trimmed_read_percent	Float	Percentage of read data with primers trimmed as determined by iVar trim
qc_check	String	A string that indicates whether or not the sample passes a set of pre-determined and user-provided QC thresholds
qc_standard	File	The file used in the QC Check task containing the QC thresholds.
qualimap_coverage_plots_html	File	Interactive HTML Plots of Coverage Across the Genome
qualimap_docker	String	Qualimap docker image used
qualimap_reports_bundle	File	Zipped bundle of Qualimap reports and plots
qualimap_version	String	Version of Qualimap used
read1_clean	File	Forward read file after quality trimming and adapter removal
read1_dehosted	File	The dehosted forward reads file; suggested read file for SRA submission
read2_clean	File	Reverse read file after quality trimming and adapter removal
read2_dehosted	File	The dehosted reverse reads file; suggested read file for SRA submission
samtools_version	String	The version of SAMtools used to sort and index the alignment file
samtools_version_primtrim	String	The version of SAMtools used to create the pileup before running iVar trim
sc2_s_gene_mean_coverage	Float	Mean read depth for the S gene in SARS-CoV-2
sc2_s_gene_percent_coverage	Float	Percent coverage of the S gene in SARS-CoV-2
trimmomatic_docker	String	The docker image used for the trimmomatic module in this workflow
trimmomatic_version	String	The version of Trimmomatic used

Variable	Type	Description
aligned_bai	String	Index companion file to the bam file generated during the consensus assembly process
aligned_bam	String	Sorted BAM file containing the alignments of reads to the reference genome
alignment_method	String	The method used to generate the alignment
bbduk_docker	String	The Docker image for bbduk, which was used to remove the adapters from the sequences
bwa_version	String	Version of BWA software used
est_percent_gene_coverage_tsv	File	Percent coverage for each gene in the organism being analyzed (depending on the organism input)
fastp_docker	String	Docker image used for fastp
fastp_html_report	String	The HTML report made with fastp
fastp_json_report	String	The JSON report made with fastp
fastp_version	String	The version of fastp used
fastq_scan_clean1_json	String	The JSON file output from fastq-scan containing summary stats about clean forward read quality and length
fastq_scan_clean2_json	File	The JSON file output from fastq-scan containing summary stats about clean reverse read quality and length
fastq_scan_num_reads_clean1	String	The number of forward reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean2	Int	The number of reverse reads after cleaning as calculated by fastq_scan
fastq_scan_num_reads_clean_pairs	String	The number of read pairs after cleaning as calculated by fastq_scan
fastq_scan_num_reads_raw1	String	The number of input forward reads as calculated by fastq_scan
fastq_scan_num_reads_raw2	Int	The number of input reserve reads as calculated by fastq_scan
fastq_scan_num_reads_raw_pairs	String	The number of input read pairs as calculated by fastq_scan
fastq_scan_raw1_json	String	The JSON file output from fastq-scan containing summary stats about raw forward read quality and length
fastq_scan_raw2_json	File	The JSON file output from fastq-scan containing summary stats about raw reverse read quality and length
fastq_scan_version	String	The version of fastq_scan
fastqc_clean1_html	String	An HTML file that provides a graphical visualization of clean forward read quality from fastqc to open in an internet browser
fastqc_clean2_html	File	An HTML file that provides a graphical visualization of clean reverse read quality from fastqc to open in an internet browser
fastqc_docker	String	The Docker container used for fastqc
fastqc_num_reads_clean1	String	The number of forward reads after cleaning by fastqc
fastqc_num_reads_clean2	Int	The number of reverse reads after cleaning by fastqc
fastqc_num_reads_clean_pairs	String	The number of read pairs after cleaning by fastqc
fastqc_num_reads_raw1	String	The number of input forward reads by fastqc before cleaning
fastqc_num_reads_raw2	Int	The number of input reverse reads by fastqc before cleaning
fastqc_num_reads_raw_pairs	String	The number of input read pairs by fastqc before cleaning
fastqc_raw1_html	String	An HTML file that provides a graphical visualization of raw forward read quality from fastqc to open in an internet browser
fastqc_raw2_html	File	An HTML file that provides a graphical visualization of raw reverse read quality from fastqc to open in an internet browser
fastqc_version	String	Version of fastqc software used
freyja_abundances	String	Abundances estimates identified by Freyja and parsed from freyja_demixed file
freyja_barcode_file	String	Barcode file used with Freyja
freyja_barcode_version	String	Name of barcode file used, or the date if update_db is true
freyja_bootstrap_lineages	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each lineage
freyja_bootstrap_lineages_pdf	String	A boxplot of the bootstrap lineages CSV file
freyja_bootstrap_summary	String	A CSV that contains the 0.025, 0.05, 0.25, 0.5 (median), 0.75, 0.95, and 0.975 percentiles for each WHO designated VOI/VOC
freyja_bootstrap_summary_pdf	String	A boxplot of the bootstrap summary CSV file
freyja_coverage	Float	Coverage identified by Freyja and parsed from freyja_demixed file
freyja_demixed	File	The main output TSV; see the section directly above this table for an explanation
freyja_demixed_parsed	File	Parsed freyja_demixed file, containing the same information, for easy result concatenation
freyja_depths	File	A TSV listing the depth of every position
freyja_fastq_wf_analysis_date	String	Date of analysis
freyja_fastq_wf_version	String	The version of the Public Health Bioinformatics (PHB) repository used
freyja_lineage_metadata_file	String	Metadata file for lineages identified by Freyja
freyja_lineages	String	Lineages in descending order identified by Freyja and parsed from freyja_demixed file
freyja_metadata_version	String	Name of lineage metadata file used, or the date if update_db is true
freyja_resid	String	Residual of the weighted least absolute deviation problem used to estimate lineage abundances identified by Freyja and parsed from freyja_demixed file
freyja_summarized	String	Sum of all lineage abundances in a particular WHO designation identified by Freyja and parsed from freyja_demixed file
freyja_variants	File	The TSV file containing the variants identified by Freyja
freyja_version	String	version of Freyja used
ivar_version_primtrim	String	Version of iVar for running the iVar trim command
kraken_human	Float	Percent of human read data detected using the Kraken2 software
kraken_human_dehosted	Float	Percent of human read data detected using the Kraken2 software after host removal
kraken_report	String	Full Kraken report
kraken_report_dehosted	File	Full Kraken report after host removal
kraken_sc2	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software
kraken_sc2_dehosted	String	Percent of SARS-CoV-2 read data detected using the Kraken2 software after host removal
kraken_version	String	Version of Kraken software used
minimap2_docker	String	The Docker image of minimap2
minimap2_version	String	The version of minimap2
nanoplot_html_clean	File	An HTML report describing the clean reads
nanoplot_html_raw	File	An HTML report describing the raw reads
nanoplot_num_reads_clean1	Int	Number of clean reads
nanoplot_num_reads_raw1	Int	Number of raw reads
nanoplot_r1_est_coverage_clean	Float	Estimated coverage on the clean reads by nanoplot
nanoplot_r1_est_coverage_raw	Float	Estimated coverage on the raw reads by nanoplot
nanoplot_r1_mean_q_clean	Float	Mean quality score of clean forward reads
nanoplot_r1_mean_q_raw	Float	Mean quality score of raw forward reads
nanoplot_r1_mean_readlength_clean	Float	Mean read length of clean forward reads
nanoplot_r1_mean_readlength_raw	Float	Mean read length of raw forward reads
nanoplot_r1_median_q_clean	Float	Median quality score of clean forward reads
nanoplot_r1_median_q_raw	Float	Median quality score of raw forward reads
nanoplot_r1_median_readlength_clean	Float	Median read length of clean forward reads
nanoplot_r1_median_readlength_raw	Float	Median read length of raw forward reads
nanoplot_r1_n50_clean	Float	N50 of clean forward reads
nanoplot_r1_n50_raw	Float	N50 of raw forward reads
nanoplot_r1_stdev_readlength_clean	Float	Standard deviation read length of clean forward reads
nanoplot_r1_stdev_readlength_raw	Float	Standard deviation read length of raw forward reads
nanoplot_tsv_clean	File	A TSV report describing the clean reads
nanoplot_tsv_raw	File	A TSV report describing the raw reads
nanoq_version	String	Version of nanoq used in analysis
primer_bed_name	String	Name of the primer bed files used for primer trimming
primer_trimmed_read_percent	Float	Percentage of read data with primers trimmed as determined by iVar trim
qc_check	String	A string that indicates whether or not the sample passes a set of pre-determined and user-provided QC thresholds
qc_standard	File	The file used in the QC Check task containing the QC thresholds.
qualimap_coverage_plots_html	File	Interactive HTML Plots of Coverage Across the Genome
qualimap_docker	String	Qualimap docker image used
qualimap_reports_bundle	File	Zipped bundle of Qualimap reports and plots
qualimap_version	String	Version of Qualimap used
read1_clean	File	Forward read file after quality trimming and adapter removal
read1_dehosted	File	The dehosted forward reads file; suggested read file for SRA submission
read2_clean	File	Reverse read file after quality trimming and adapter removal
read2_dehosted	File	The dehosted reverse reads file; suggested read file for SRA submission
samtools_version	String	The version of SAMtools used to sort and index the alignment file
samtools_version_primtrim	String	The version of SAMtools used to create the pileup before running iVar trim
sc2_s_gene_mean_coverage	Float	Mean read depth for the S gene in SARS-CoV-2
sc2_s_gene_percent_coverage	Float	Percent coverage of the S gene in SARS-CoV-2
trimmomatic_docker	String	The docker image used for the trimmomatic module in this workflow
trimmomatic_version	String	The version of Trimmomatic used

Freyja_Plot_PHB

This workflow visualizes aggregated freyja_demixed output files produced by Freyja_FASTQ_PHB in a single plot (pdf format) which provides fractional abundance estimates for all aggregated samples.

Options exist to provide lineage-specific breakdowns and/or sample collection time information.

Inputs

This workflow runs on the set level.

Terra Task Name	Variable	Type	Description	Default Value	Terra Status
freyja_plot	freyja_demixed	Array[File]	An array containing the output files (freyja_demixed) made by Freyja_FASTQ		Required
freyja_plot	freyja_plot_name	String	The name of the plot to be produced. Example: "my-freyja-plot"		Required
freyja_plot	samplename	Array[String]	The names of the samples being analyzed		Required
freyja_plot	collection_date	Array[String]	An array containing the collection dates for the sample (YYYY-MM-DD format)		Optional
freyja_plot_task	cpu	Int	Number of CPUs to allocate to the task	1	Optional
freyja_plot_task	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
freyja_plot_task	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/freyja:2.0.1	Optional
freyja_plot_task	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
freyja_plot_task	mincov	Int	The minimum genome coverage used as a cut-off of data to include in the plot	60	Optional
freyja_plot_task	plot_day_window	Int	The width of the rolling average window; only used if plot_time_interval is "D"	14	Optional
freyja_plot_task	plot_lineages	Boolean	If true, will plot a lineage-specific breakdown	False	Optional
freyja_plot_task	plot_time	Boolean	If true, will plot sample collection time information (requires the collection_date input variable)	False	Optional
freyja_plot_task	plot_time_interval	String	Options: "MS" for month, "D" for day	MS	Optional
version_capture	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/alpine-plus-bash:3.20.0	Optional
version_capture	timezone	String	Set the time zone to get an accurate date of analysis (uses UTC by default)		Optional

Analysis Tasks

freyja_plot_task Details

This task will aggregate multiple samples together, and then creates a plot. Several optional inputs dictate the plot appearance (see each variable's description for more information).

Freyja Plot Technical Details

	Links
Task	wf_freyja_plot.wdl
Software Source Code	https://github.com/andersen-lab/Freyja
Software Documentation	https://github.com/andersen-lab/Freyja

Outputs

Variable	Type	Description
freyja_demixed_aggregate	File	A TSV file that summarizes the freyja_demixed outputs for all samples
freyja_plot	File	A PDF of the plot produced by the workflow
freyja_plot_metadata	File	The metadata used to create the plot
freyja_plot_version	String	The version of Freyja used
freyja_plot_wf_analysis_date	String	The date of analysis
freyja_plot_wf_version	String	The version of the Public Health Bioinformatics (PHB) repository used

Freyja_Dashboard_PHB

This workflow creates a group of interactive visualizations based off of the aggregated freyja_demixed output files produced by Freyja_FASTQ_PHB called a "dashboard". Creating this dashboard requires knowing the viral load of your samples (viral copies/litre).

Warning

This dashboard is not "live" — that is, you must rerun the workflow every time you want new data to be included in the visualizations.

Inputs

This workflow runs on the set level.

Terra Task Name	Variable	Type	Description	Default Value	Terra Status
freyja_dashboard	collection_date	Array[String]	An array containing the collection dates for the sample (YYYY-MM-DD format)		Required
freyja_dashboard	freyja_dashboard_title	String	The name of the dashboard to be produced. Example: "my-freyja-dashboard"		Required
freyja_dashboard	freyja_demixed	Array[File]	An array containing the output files (freyja_demixed) made by Freyja_FASTQ workflow		Required
freyja_dashboard	samplename	Array[String]	The names of the samples being analyzed		Required
freyja_dashboard	viral_load	Array[String]	An array containing the number of viral copies per liter		Required
freyja_dashboard_task	config	File	(found in the optional section, but is required) A yaml file that applies various configurations to the dashboard, such as grouping lineages together, applying colorings, etc. See also https://github.com/andersen-lab/Freyja/blob/main/freyja/data/plot_config.yml.		Optional, Required
freyja_dashboard	dashboard_intro_text	File	A file containing the text to be contained at the top of the dashboard.	SARS-CoV-2 lineage de-convolution performed by the Freyja workflow (https://github.com/andersen-lab/Freyja).	Optional
freyja_dashboard_task	cpu	Int	Number of CPUs to allocate to the task	1	Optional
freyja_dashboard_task	disk_size	Int	Amount of storage (in GB) to allocate to the task	100	Optional
freyja_dashboard_task	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/staphb/freyja:2.0.1	Optional
freyja_dashboard_task	headerColor	String	A hex color code to change the color of the header		Optional
freyja_dashboard_task	memory	Int	Amount of memory/RAM (in GB) to allocate to the task	2	Optional
freyja_dashboard_task	mincov	Float	The minimum genome coverage used as a cut-off of data to include in the dashboard. Default is set to 60 by the freyja command-line tool (not a WDL task default, per se)		Optional
freyja_dashboard_task	scale_by_viral_load	Boolean	If set to true, averages samples taken the same day while taking viral load into account	False	Optional
freyja_dashboard_task	thresh	Float	The minimum lineage abundance cut-off value		Optional
version_capture	docker	String	The Docker container to use for the task	us-docker.pkg.dev/general-theiagen/theiagen/alpine-plus-bash:3.20.0	Optional
version_capture	timezone	String	Set the time zone to get an accurate date of analysis (uses UTC by default)		Optional

Analysis Tasks

freyja_dashboard_task Details

This task will aggregate multiple samples together, and then create an interactive HTML visualization. Several optional inputs dictate the dashboard appearance (see each variable's description for more information).

Freyja Dashboard Technical Details

	Links
Task	wf_freyja_dashboard.wdl
Software Source Code	https://github.com/andersen-lab/Freyja
Software Documentation	https://github.com/andersen-lab/Freyja

Outputs

Variable	Type	Description
freyja_dashboard	File	The HTML file of the dashboard created
freyja_dashboard_metadata	File	The metadata used to create the dashboard
freyja_dashboard_version	String	The version of Freyja used
freyja_dashboard_wf_analysis_date	String	The date of analysis
freyja_dashboard_wf_version	String	The version of the Public Health Bioinformatics (PHB) repository used
freyja_demixed_aggregate	File	A TSV file that summarizes the freyja_demixed outputs for all samples

Running Freyja on other pathogens

Experimental Feature

Please be aware this is an experimental feature and we cannot guarantee complete functionality at this time.

The main requirement to run Freyja on other pathogens is the existence of a barcode file for your pathogen of interest. Currently, barcodes exist for the following organisms:

• SARS-CoV-2 (default)
• FLU-B-VIC
• H1N1
• H3N2
• H5Nx-cattle
• H5NX
• MEASLESN450
• MEASLESgenome
• MPX
• RSVa
• RSVb

Freyja barcodes for other pathogens

Data for various pathogens can be found in the following repository: Freyja Barcodes

Folders are organized by pathogen, with each subfolder named after the date the barcode was generated, using the format YYYY-MM-DD, as well as a "latest" folder. Barcode files are named barcode.csv, and reference genome files are named reference.fasta.

There are two ways to run Freyja_FASTQ_PHB for non-SARS-CoV-2 organisms:

• Using the freyja_pathogen optional input (limited set of allowable organisms)
• Providing the appropriate barcode file through the freyja_barcodes optional input (any organism for which barcodes are supplied)

Using the freyja_pathogen flag

When using the freyja_pathogen flag, the user must set the optional update_db flag to true, so that the latest version of the barcode file is automatically downloaded by Freyja.

Figure 2: Optional input for Freyja_FASTQ_PHB to provide the pathogen to be used by Freyja

Figure 2

Allowed options:

• SARS-CoV-2 (default)
• MPXV
• H1N1pdm
• H5NX
• FLU-B-VIC
• MEASLESN450
• MEASLES
• RSVa
• RSVb

Warning

The freyja_pathogen flag is not used if a barcodes file is provided. This means that this option is ignored if a barcode file is provided through freyja_barcodes.

Providing the appropriate barcode file

The appropriate barcode file for your organism of interest and reference sequence need to be downloaded and uploaded to your Terra.bio workspace. When running Freyja_FASTQ_PHB, the appropriate reference and barcodes file need to be passed as inputs. The first is a required input and will show up at the top of the workflows inputs page on Terra.bio (Figure 3).

Figure 3: Required input for Freyja_FASTQ_PHB to provide the reference genome to be used by Freyja

Figure 3

The barcodes file can be passed directly to Freyja by the freyja_barcodes optional input (Figure 4).

Figure 4: Optional input for Freyja_FASTQ_PHB to provide the barcodes file to be used by Freyja

Figure 4

References

If you use any of the Freyja workflows, please cite:

Karthikeyan, S., Levy, J.I., De Hoff, P. et al. Wastewater sequencing reveals early cryptic SARS-CoV-2 variant transmission. Nature 609, 101–108 (2022). https://doi.org/10.1038/s41586-022-05049-6

Freyja source code can be found at https://github.com/andersen-lab/Freyja

Freyja barcodes (non-SARS-CoV-2): https://github.com/gp201/Freyja-barcodes