COVID-19 variants FAQ for members #


Which COVID-19 variants are present in Washington state? #

The Washington State Depart­ment of Health currently lists four variants of concern. Each of these variants are consid­ered highly infec­tious and transmissible.

  • Alpha (B.1.1.7) Based on published studies, this variant poten­tially causes more severe symptoms and increased risk of death in individ­uals who are infected. This variant was first identi­fied in the United Kingdom.
  • Beta (B.1.351) Results from exper­i­mental research studies show that the B.1.351 variant contains mutations that make it less likely to respond to antibody treat­ments. This variant was first identi­fied in South Africa.
  • Gamma (P.1) Results from exper­i­mental research studies show that the P.1 (gamma) variant contains mutations that make it less likely to respond to antibody treat­ments. This variant was first identi­fied in Japan/​Brazil.
  • Delta (B.1.617.2 ) Based on prelim­i­nary evidence, some antibody treat­ments may be less effec­tive against the delta variant, and vaccine effec­tive­ness may be lower. The delta variant spreads about twice as easily from one person to another than previous strains of the virus. This variant was first identi­fied in India.

There are additional variants in Washington state which are currently labeled variants of interest. These are the Epsilon, Eta, Iota, and Kappa variants. 



How does the Washington State Department of Health determine which variants are currently circulating? #

The Depart­ment of Health uses genome sequencing to deter­mine how a virus is changing over time. A sample of positive COVID-19 PCR tests are used. Washington state is currently sequencing at least 10% of positive COVID-19 tests, equating to tens of thousands of tests since January 2020.



Is there one variant that is more prevalent than others? #

The Delta variant has most recently become the predom­i­nant variant in Washington state, as well as the United States. Data shows that those infected with the Delta variant have a higher viral load than those infected with other variants and is twice as conta­gious as other variants. Data also shows that unvac­ci­nated individ­uals who test positive with the Delta variant have more severe illness than older variants.



What criteria are used to determine a vaccine breakthrough’ case? #

The criteria for identi­fying vaccine break­through cases include a positive PCR or antigen lab test at least 14 days after a person received their last recom­mended dose of an autho­rized COVID-19 vaccine. It takes approx­i­mately two weeks after the final dose of vaccine has been admin­is­tered for the body to build a high level of protec­tion against the virus. Infec­tions that occur within the first fourteen days after any dose in an FDA-approved vaccine regimen is not consid­ered a break­through case as that person is not consid­ered fully vacci­nated. Less than 1% of COVID-19 cases in Washington are in fully vacci­nated people.



Are COVID-19 vaccines effective? #

All FDA-approved vaccines have shown effec­tive­ness against all four variants of concern, and over 162 million Ameri­cans have been fully vacci­nated against COVID-19. COVID-19 vaccines have been proven effec­tive in reducing the incidence of severe illness, hospi­tal­iza­tion, and death. Over 99% of current COVID-19 hospi­tal­iza­tions and deaths are unvac­ci­nated individ­uals. Since the first COVID-19 vaccine was made avail­able, deaths due to COVID-19 in the United States have dropped by 70%.



How does the Washington State Department of Health determine vaccine breakthrough cases? #

The Washington Depart­ment of Health finds break­through cases in two ways: 

  • A DOH inves­ti­gator may conduct inter­views with individ­uals who have tested positive for COVID-19 to assess whether they have also been vaccinated.
  • Cross-checking positive COVID-19 results with Washington state’s immuniza­tion registry.



Are vaccine breakthrough cases more common in one variant than another? #

DOH reports that vaccine break­through cases are being prior­i­tized for whole genome sequencing so that the distri­b­u­tion of variants detected among break­through cases can be contin­u­ally monitored. Currently, the Delta and Alpha variants have the highest rate of vaccine break­through. However, all break­through cases in Washington state make up less than 1% of total confirmed COVID-19 cases. 



Are vaccine breakthrough cases more common in one brand of vaccine than another? #

DOH reports that vaccine break­through has been associ­ated with all three current autho­rized vaccines. It is misleading to look at break­through cases by vaccine brand as the number of admin­is­tered doses varies by brand. Other variables include differ­ences in dosing sched­ules. These factors make it diffi­cult to directly compare numbers of break­through cases among vaccine brands. 



Is the vaccine recommended for those who have been previously infected with COVID-19? #

The Advisory Committee on Immuniza­tion Practices (ACIP) recom­mends anyone who previ­ously has had COVID-19 to get the vaccine. Data shows it is uncommon to be re-infected with COVID-19 in the 90 days after infec­tion, so there may be some natural immunity. However, it is unknown how long natural immunity might last. People who currently have COVID-19 should wait to get vacci­nated until symptoms resolve, and their isola­tion period is finished. People who were recently exposed to COVID-19 should also wait to get the vaccine until after their quaran­tine period as long as they can safely quaran­tine away from other people. If there is a high risk they could infect others, they may be vacci­nated during their quaran­tine period to prevent spreading the disease. 



What resources are available regarding COVID-19 variants and breakthrough cases in Washington State? #

The Washington State Depart­ment of Health produces weekly reports on both COVID-19 variants and vaccine break­through cases. These reports are published online and are updated on Wednes­days. Additional infor­ma­tion can also be found from the following resources: