Skip to main content
King County logo
Updated August 10, 2021

This is an update to a previous Health Advisory, dated March 22, 2021. New recommendations will be highlighted below.

Washington State Department of Health (DOH) is working to continue sequencing priority SARS-CoV-2 specimens. In an effort to increase sequencing, DOH has broadened criteria for submission of isolates for sequencing. Sequencing is occurring at Washington State Public Health Laboratories (PHL), as well as at partner laboratories. The following specimen types are acceptable to submit for sequencing:

  • RNA extract (preferred)
  • Nasal swab, nasopharyngeal swab, or mid-turbinate swab in VTM/UTM or transport medium
  • Lower respiratory tract fluid (BAL, tracheal aspirate, or sputum) – if intubated (these specimen types will be held until sequencing is available at PHL)

Select a tab below to navigate through sections:

  • Be aware that infections with all currently designated SARS-CoV-2 Variants of Concern (VOC) have been identified in King County residents through whole genome sequencing (WGS) since the end of January 2021.

  • Support surveillance for possible VOCs by reporting via email to cases of SARS-CoV-2 infection that meet the following criteria below for WGS:

    • NEW Suspected vaccine breakthrough, defined as:
      • All doses in vaccine series administered, and
      • >14 days have elapsed between the final vaccine dose and the specimen collection date of a specimen
      • NEW Facilities, testing sites, and investigators no longer need to send King County reports of suspected vaccine breakthrough. King County has automated this process to automatically identify and report all suspected vaccine breakthrough cases.
    • Specimens positive for "S-dropout" meaning the "S" RNA target, for the COVID spike protein, of the PCR platform is negative and the other RNA targets are positive (also called S gene target failure, SGTF). Only a limited number of PCR platforms are able to detect this
    • Any suspected reinfection case, regardless of whether prior sample available (repeat PCR positive test > 90 days after initial PCR positive test)
    • Outbreaks concerning for variants (submit 3 specimens from the outbreak)
      • Examples include fast spreading large outbreaks or increased hospitalizations from an outbreak
    • Unusual clinical presentations that may be associated with more severe or different clinical syndromes. Examples include:
      • Critical illness or death in a previously healthy child or young adult (age <40) and/or other unusual clinical presentations identified by clinicians or LHJs
    • Suspected cases of zoonotic transmission

  • Include the following information in your email. If you are unable to securely send protected health information, please note this in your email and we can call you to get the remaining information:
    • Name and date of birth of person tested
    • Name/manufacturer of vaccine given and dates of each dose
    • Name of laboratory
    • Dates of travel and to where
    • Collection dates of positives
    • Reason for concern

  • If your facility routinely performs screening testing of healthcare staff or case finding testing in response to cases or clusters of COVID-19 in your facility, PLEASE CONTINUE to test individuals who have completed vaccination as you would if they were not vaccinated.

  • For laboratories, please support surveillance for possible VOC's by continuing to submit cases of identified "S-drop out" and by completing this form Submission Form ( and submitting samples to DoH upon request form Public Health.

  • Important considerations:
To date, Public Health – Seattle & Kind County has confirmed cases of all currently known SARS-CoV-2 VOC among King County residents. Preliminary data on VOCs suggests that they can be more transmissible, associated with higher viral loads, and possibly more severe disease. The Delta strain is currently the predominant strain in the United States, as well as here in King County. Intensifying surveillance efforts and early reporting by healthcare providers and laboratories of possible cases of infection with any VOC helps inform COVID-19 outbreak response in King County.