06/23/2022: Lab Advisory: CDC Updates Specimen Collection Guidelines for Mpox Virus

CDC's Laboratory Outreach Communication System (LOCS)

Audience: Clinical Laboratory Professionals

Level: Laboratory Advisory

This message is to update the Lab Advisory: CDC Specimen Collection Guidelines for Mpox Virus published on 05/31/2022. CDC can now accept lesion swabs in viral transport media as stated in the guidelines below.

Clinical laboratories should follow these guidelines when collecting specimens for mpox virus testing:

  • Collect at least two swabs from the same lesion.
  • Swab or brush lesion vigorously with two separate sterile swabs. Use a sterile nylon, polyester, or Dacron swab with a plastic, wood, or thin aluminum shaft. Do not use other types of swabs.
  • If possible, sample paired specimens from multiple lesions on different parts of the body and with differing appearances. CDC suggests 2-3 lesions total.
  • Place swabs in individual sterile containers. CDC can now accept the following specimens:- Dry lesion swab
    – Lesion swabs in viral transport media (VTM)
    – Lesion crusts
  • Refrigerate (2–8°C) or freeze (-20°C or lower) specimens within an hour after collection.
  • CDC must receive lesion swabs in VTM and lesion crusts within 7 days of specimen collection.
  • CDC will reject specimens that are greater than 8°C upon receipt. Ship on dry ice as category B.
  • Send both swabs to your state or territorial public health laboratory. Send all specimens through the state or territorial public health department, unless authorized to send them directly to CDC.

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The Laboratory Outreach Communication System

Laboratory Outreach Communication System (LOCS) | Division of Laboratory Systems (DLS)

Center for Surveillance, Epidemiology, and Laboratory Services (CSELS)

Centers for Disease Control and Prevention (CDC)