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Updated February 24, 2021

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  • Be aware that multiple cases of infections with 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 covidtestingstrategy@kingcounty.gov cases of SARS-CoV-2 infection that meet one of the following criteria below for WGS:
    • Suspected cases of reinfection only if both specimens (one from each infection episode) are available OR sequencing results are available from the original specimen for the following:
      • Two positive SARS-CoV-2 PCR tests > 90 days apart, OR
      • Individual with new symptoms of COVID-19 and a positive PCR test 45–89 days since first SARS-CoV-2 infection AND no obvious alternate etiology for symptoms, OR had close contact with a laboratory-confirmed COVID-19 case
    • Individuals with a positive SARS-CoV-2 test with travel in the 14 days prior to symptom onset to areas where CDC-listed variants of concern are widely circulating
    • Investigations of suspected vaccine breakthrough disease as defined by:
      • All doses in vaccine series administered
      • >14 days have elapsed between the final vaccine dose and the specimen collection date of a PCR+ specimen
    • 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.

  • Include the following information in your email report of a suspected VOC case. (If you are unable to securely send PHI please note this in your email and we can call you to get the remaining information).
    • Name and date of birth of person tested
    • Dates of positive tests if it is a possible reinfection, if applicable
    • List of symptoms and reason for testing for both testing events
    • Area traveled to where CDC-listed variant of concern is widely circulating, if applicable
    • Name/Manufacturer of vaccine given and date of each dose, if applicable
    • Was S-dropout identified

  • Ensure that your laboratory saves the relevant specimen(s), and if your lab has not already coordinated with Washington State Public Health Laboratory for submission of qualifying specimens, Public Health can help facilitate this.

  • 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.
Public Health has confirmed cases of the SARS-CoV-2 B.1.1.7 (UK) variant of concern (VOC) and at least 1 B.1.351 (South African) VOC among King County residents among a small number of specimens that have been tested. The B.1.1.7 strain is expected to become the predominant strain in the United States in the coming months as its transmission has been detected in most states. Because <5% of all positive SARS-CoV-2 samples are sequenced statewide, the number of cases of infection with a SARS-CoV-2 VOC likely only represents a proportion of the true number of VOC infections in our area. Preliminary data on the B.1.1.7 variant suggests that it is more transmissible, associated with higher viral loads, and possibly more severe disease. Early data on the B.1.351 strain suggests that the level of protection from infection with earlier strains and to some degree from vaccines is lower for this strain; it is not yet clear whether this strain spreads more rapidly or results in more severe illness. 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 efforts in King County.