In July, UT Southwestern and Texas Health Resources announced they would collaborate on a COVID-19 prevalence study to measure how the virus spreads through the local population. One month in, responses are starting to give researchers a look at how the disease impacts the community, including the prevalence of asymptomatic carriers. But there is much work yet to be done if the study wants to meet its goals.
More than 3 million people in the U.S. have contracted COVID-19, and more than 12 million worldwide have tested positive, with 550,000 people worldwide dying as a result. In Texas, over 515,000 people have tested positive and more than 9,000 people have died. Nearly 90,000 of those positive cases have been in Dallas and Tarrant counties. But with limited testing and individuals self-selecting whether they get testing, data gaps remain in understanding how the disease impacts all populations in the region.
The study’s goal is to test 15,000 people in Dallas County and an equal number in Tarrant County, whether or not they have any symptoms. An additional 14,000 essential workers are also targeted for testing. Researchers say it is the largest such effort in the country. Around 5,000 invitations have been sent out in Dallas County, and 2,000 in Tarrant County. The letter asks participants to schedule a free COVID-19 test. About 300 people had responded when I spoke with researchers running the study last week.
Because between 30 percent to 40 percent of those who get COVID-19 are asymptomatic, relying on those who volunteer to get tested or have symptoms can be missing significant portions of the population. When policymakers are thinking about mask orders, closing businesses, or other measures, it is essential to have accurate data about its prevalence.
The invitation asks a representative sample of residents to complete a brief, 10-minute survey that assesses risk factors, any prior testing, and any symptoms that may be present. The invite directs them to one of several testing sites regardless of their COVID-19 history, where they receive a free nasal swab and a blood test.
The invitations were sent to a variety of racial and ethnic backgrounds and socio-economic levels to see how the disease impacts different populations. “We have taken tremendous efforts to get a random and representative sample that is truly representative of the region,” says principal investigator Dr. Amit Singal, an Associate Professor of Medicine at UT Southwestern Medical Center.
Community Engagement Strategy
The mailed invitations are paired with community engagement campaigns and other forms of outreach. “We realize there are multiple ways to connect,” says co-investigator Dr. Andrew Masica, chief medical officer of Reliable Health at Texas Health Resources.
But with such a large population of potential respondents, reaching everyone and getting them to follow through on the invitation is a significant challenge. The study is targeting micro-communities and trusted influencers in those communities, hosting town hall meetings, training study ambassadors to reach out and interact with their communities to make sure people are aware of the study and its importance, says co-investigator Jasmin Tiro, an associate professor of population and data sciences at UT Southwestern Medical Center.
The number of respondents was set at 44,000 because it allows researchers to see slight variations (1 to 2 percent) in racial and ethnic groups in terms of COVID-19 prevalence, Singal says. Most data show that COVID-19 disproportionately impacts Hispanic and Black populations, but the study might give more insight into why those disparities might exist. The study will also localize the data and publicize it while the research is ongoing. “It is truly a better sense of what is happening in DFW,” says Masica. “We can’t compare what is in Spain to North Texas. This local data can inform national discussions and provide unique characteristics about a community.”
The results could help inform healthcare delivery and potential interventions for specific populations while providing information about risk factors, antibody testing, antibody response, and how it changes over time. A selection of those in the study will be asked to regularly test for six to 12 months after their initial test to see the long term impact of the virus and potential immunity.
The longevity of the study will also see how the community handles continued social distancing. “Social distancing is not an easy thing,” Tiro says.”Humans are social, and we want to measure their ability to maintain social distancing over time and how our data are evolving”
Researchers hope to complete the study before the end of the year, but much depends on active community engagement and responses from those invited to participate.
Although they are hopeful they will reach their data targets, UTSW and THR are not waiting until all 44,000 people have responded to analyze results and disseminate that information to the public. With just a few hundred responses so far, researchers said they would have effects to report within the next month. “We wish we had that data yesterday, and we understand the importance of having it as soon as possible,” Singal says.