Some important updates to COVID-19 data are happening at the local and state level. Read more to learn about how we’re now including probable COVID-19 cases in our data reporting, and how to interpret recent test data with a bit of caution.

Antigen-positive test results now included in DOH dashboards 

The Washington State Department of Health will now include antigen-positive COVID-19 cases in the COVID-19 Data Dashboard and the COVID-19 Risk Assessment Dashboard, and on our county-level dashboards on our COVID-19 data page.

Starting with today’s data dashboard update, case, hospitalization, and death counts will include both confirmed and probable cases. You’ll see the numbers on our dashboard change as data from antigen tests are added in.

• Probable cases are individuals with a positive antigen test for COVID-19 and no positive molecular (PCR) test.
• Confirmed cases are individuals with a positive molecular (PCR) test for COVID-19. 

Testing data, including the positivity rate and total number of tests, will only include confirmed cases (molecular tests).

Antigen vs. Molecular Testing 

There are two different types of tests that are used currently to diagnose someone with COVID-19:

• Antigen tests detect certain proteins that are part of the COVID-19 virus. If the proteins are present, it means someone is infected with the virus. 
• Molecular tests, including PCR tests, look for genetic material inside the virus to diagnose a person as “COVID-19 positive”. Molecular tests take more time than antigen tests to perform, but they are generally more accurate than antigen tests.  

You can learn more about antigen testing at doh.wa.gov/testing.

How this helps

Including antigen-positive test results in our case numbers will provide a more accurate picture of community transmission and help guide efforts to respond to COVID-19. 

Currently, about 5% of all COVID-19 cases are from antigen testing, and the remaining 95% is from molecular testing. Even though antigen testing currently represents just a small percentage of all COVID-19 testing in Washington, it’s likely that antigen tests will be used more in the future.

Ongoing Data Issues

Data validation is a routine part of the data analysis involved with reporting COVD-19 data that ensures we provide accurate information. It includes removing duplicate data, like cases that show up more than once in lab reports. In the middle of November, laboratory COVID-19 testing reached levels that exceeded the capacity of DOH’s reporting system, and that slowed down the normal processes to validate, or “clean” data. 

While DOH continues to validate data, you should interpret some information in the data dashboards with caution. Specifically:

• Negative test results data from November 21, 2020 through today are incomplete.
• Positive test results reported since December 11, 2020 are incomplete.

These numbers will change as the data is checked and then finalized. For the most up-to-date and accurate data, check back often.