To slow the spread of coronavirus, we need more testing. 

Washington state’s recovery - from understanding and addressing the pandemic to its strategy for reopening - relies on it. 

In response, UW Medicine, the Washington State Department of Health, and the Paul G. Allen Family Foundation announced a new partnership to launch a study to determine the percentage of Washingtonians who have been infected with COVID-19.

“Comprehensive, high-quality data that statistically represents Washington’s diverse communities and populations is critical to support the state’s healthcare response and reopening,” said Jody Allen, co-founder and chair of the Paul G. Allen Family Foundation. “This statewide study will provide a necessary baseline understanding of COVID-19 presence in communities to inform smart policy decisions as we all move forward with Washington’s economic and health recovery.”

As one of the first in the country to develop a COVID-19 test, UW Medicine’s Virology Laboratory will lead the 7,000 person study, which will sample rural and urban populations throughout the state and within racially, ethnically and socioeconomically diverse communities.

We spoke with Dr. Keith Jerome, head of the Virology Division at UW Medicine and the principal investigator of the study, to learn more about the tests, what they’re hoping to learn, and the broader implications of the study.

Why is this 7,000 person study so important?

The vast majority of testing done so far has been looking for the virus itself. So it’s a snapshot in time, of how many people are infected at this moment. Our new study will also look for antibodies, which are made as the body fights off the infection. The antibodies last a long time after COVID-19 is passed, so the study will tell us how many people have been infected at some point during the whole pandemic. That will help doctors and public policy makers tell what proportion of our population has been infected, understand what steps seems to have been effective in minimizing infections, and make plans as we move forward into the fall and winter months.

In what ways will UW Medicine study differ from previous COVID-19 antibody studies?

Previous studies in Washington state have used mostly “convenience” samples, which are relatively easily obtained. These might be leftover samples from other lab testing, from blood donors, or from employee or other defined groups. The problem with convenience samples is that you can never be sure they represent the public as a whole. The UW Medicine/Allen Foundation study will use a completely different strategy to enroll participants, which will ensure that the results are truly representative of our state.

When will the testing begin and results available? Will it be shared with the public?

Testing will begin in July and August of 2020, and participants will receive their results back within a week or so. We plan to release the results of our first round of sampling as soon as we finish the analysis, probably in September.

How can we be sure these results are accurate?

UW Medicine Virology is extremely careful in ensuring that the results of our testing are accurate. We have published many papers in the scientific literature describing our COVID-19 tests and their performance, so that other labs can benefit from our experience. One of the most important papers was about our antibody test. 

Many of the early antibody tests gave very unreliable results, and UW Medicine Virology did not offer antibody testing until we found a test (manufactured by Abbott) that was extremely accurate. In our paper describing the antibody test, we found that it was 100% sensitive (meaning that every patient we studied who had COVID-19 also developed antibodies), and 99.9% specific (of over 1000 samples from patients before COVID-19 started circulating, only 1 had a borderline false-positive result).

Data indicates COVID-19 has disproportionality impacted Black and Latinx people. How does this study ensure these groups are represented?

Participants in our study will be chosen by a statistical method that ensures the composition of the study population matches that of the population as a whole. For groups like Black and Latinx people, we will also “oversample,” which means we’ll add some additional participants, to make sure that we can be confident in the study results for these groups.

Can you tell us how an antibody study like this works?

Participants will provide a blood draw at each of the three visits, about four months apart (at the first visit they’ll also get a nasal swab to test for the virus itself). The blood will be separated into the portion that contains the antibodies, and transported back to the lab in Seattle. In the lab, the portion with the antibodies (called serum) will be put on a specialized instrument that can detect the antibodies to COVID-19 in less than an hour.

What does it mean to have antibodies against a virus and how long do these last or live inside humans?

Antibodies are made within a week or two after an infection with an antibody or virus, and are one of the ways the body fights back against the infection. If they’re present, it shows that someone has been infected with a particular virus or bacterium, and they usually provide at least some protection from future infection. For some infections, but not all, the antibodies remain detectable for life. For COVID-19, we’re not sure how long the antibodies will last, but from what we know about other coronaviruses (which are in the same family as the virus that causes COVID-19), they probably won’t last a lifetime. We’re hoping they’ll last at least a year or two, and provide some protection against the virus.

Does having antibodies mean you are immune to COVID-19? Does everyone infected with the COVID-19 virus develop antibodies?

From our study, everyone who was hospitalized with COVID-19 made antibody within about two weeks. We’re not completely sure about people who have very mild COVID-19. They might make less antibody, or even so little that we can’t detect it.
 
We also can’t say for sure how much protection having antibodies will provide against getting COVID-19 again. From what we know about other coronaviruses, it’s likely they give you at least some protection. It’s possible, for example, that a person with antibodies might still get infected, but that their clinical illness would be more likely to be mild rather than severe.
 
Both these are questions we are hoping to answer with our study.

What are some misunderstandings the general public probably has about antibody testing?

Early on in the pandemic, there were some antibody tests available that were very inaccurate, and gave antibody testing a bad name. But as we talked about above, the test we perform at UW Virology is extremely reliable and accurate.

How will determining the prevalence of COVID-19 antibodies throughout the state of Washington help in the battle against COVID-19 infections?

The results will tell us where in the state infection has been most common, what groups of people have been most infected, and what proportion of the overall population has been infected. These data may be used for decisions about what kind of preparations by businesses and government are needed going into fall and winter, what sort of precautions will be needed, and how to best prepare ourselves for the next phase of the pandemic. We are also very willing to share our results with states that won’t have a similar serostudy themselves.