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VRDL Test Page - Monkeypox Virus Whole Genome Sequencing

VIRAL AND RICKETTSIAL DISEASE LABORATORY

Test Order
Monkeypox Virus Identification - Whole Genome Sequencing

Information Category	Information Detail
Pre-Approval	Not Applicable
Supplemental Information Requested	• Previous test results: Sampled lesion must be positive for Monkeypox Virus (MPXV) using a generic MPXV or MPXV clade II-specific assay or a Non-variola orthopoxvirus assay. Samples that test negative for clade II MPXV but are positive in a generic MPXV-specific assay are not acceptable, since these may fall under Select Agent rules (See Additional Information). • Ct values, lesion site, treatment with tecovirimat or other antiviral, vaccination status, and outbreak location (if applicable) should be indicated on the submittal form when available.
Submittal Forms	Specimens must be accompanied with a hard copy of the completed VRDL General Purpose Specimen Submittal Form (PDF) or a form generated in the VRDL Lab Web Portal. Mpox group submittal form available on request from VRDL.Submittal@cdph.ca.gov.
Methodology	Whole Genome Sequencing (LDT) (Surveillance use only)
Reflex Testing	May be referred to CDC for additional testing
Acceptable Specimen Type(s) and Collection Method	Human Specimens: Lesion swabs, in Viral Transport Medium (preferred) or dry Dry lesion scabs or crusts Positive nucleic acid extracts Lesion specimens or nucleic acid extracts only acceptable from clade II MPXV, MPXV (generic), or Non-variola orthopox virus–positive persons.
Minimum Volume Requested	Lesion Swabs: 200 µL residual VTM or PBS from positive swab, or Duplicate swab from positive lesion placed in 1-3 mL VTM, or Dry swab Nucleic acid extracts: 25 µL
Transport Medium (if using)	Viral Transport Medium
Specimen Labeling	Each specimen tube must be labeled with at least two unique patient identifiers; e.g., patient full name and date of birth.
Storage & Preservation of Specimen / Shipping Conditions	Freeze or refrigerate specimens promptly after collection. Freezing is strongly recommended. Ship refrigerated specimens to VRDL on cold packs. Ship frozen specimens to VRDL on dry ice.
Shipping Instructions	Work with your local public health department to ensure samples are packaged according to instructions for Biological Substance – Category B (UN 3373) shipment. Ship specimens and a hard copy of the completed submittal forms to: CDPH VRDL ATTN: Specimen Receiving 850 Marina Bay Parkway Richmond, CA 94804 Phone: 510-307-8585
Turnaround Time	60 business days
Interferences & Limitations	This service is provided for public health investigational needs only. This is not a validated, diagnostic test, and results shall not be used for clinical management. Samples with low viral load (real-time PCR Cycle Threshold >30) or that have been improperly stored or subjected to conditions that negatively impact nucleic acid integrity may not provide interpretable results. Results may not confirm or predict anti-viral resistance.
Additional Information	Clade II MPXV or undifferentiated MPXV-positive samples or those that are non-variola virus-positive from suspected mpox cases are acceptable. MPXV-positive samples that are known not to be clade II are not acceptable. As a reminder, MPXV clade I is regulated as a select agent and must be reported to the CDC DSRC within 7 days. CDPH Mpox Disease Information CDC Guidelines for Collecting and Handling Specimens for Mpox Testing
VRDL Points of Contact	Medical and Epidemiology Liaisons: (510) 307-8585 or VRDL.Submittal@cdph.ca.gov

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