SARS-CoV-2 Testing Behavior in Symptomatic Adults and the Role of Exposure Risk, Susceptibility and Healthcare Access in a U.S. National Cohort (2020-2023).

Background: The COVID-19 pandemic highlighted the critical role of diagnostic testing for managing transmission and reducing the risk of serious illness. This study examines SARS-CoV-2 testing behavior patterns, including at-home and laboratory tests, among adults with COVID-like symptoms from 2020-2023. We explore characteristics associated with testing frequency and assess the impact of SARS-CoV-2 exposure risk, susceptibility to COVID-19 complications, and barriers to healthcare access on frequency of testing when ill. Methods: The CHASING COVID Cohort study comprises a diverse sample of U.S. adults, with data collected quarterly from March 2020 to December 2023. We categorized participants with COVID-like symptoms reported 2+ times (N = 3,929) as 'frequent testers' if they tested ≥ 66% of the time when symptomatic, 'occasional testers' if they tested > 33% and < 66% of the time, and 'infrequent testers' if they tested ≤ 33% of the time. Informed by the Blumenshine Pandemic Disease Framework, we examined the impact of SARS-CoV-2 exposure risk, susceptibility to COVID-19 complications if infected, and barriers to healthcare access on testing frequency using crude and adjusted log-binomial regression models. Results: Infrequent testers were more likely to be female, Hispanic or Black/non-Hispanic, have an annual household income <$35,000, have fewer years of education, have children in the household, reside in a rural area or southern state. Testing frequency was positively correlated with COVID-19 vaccination, willingness to take antivirals, trust in public health agencies and healthcare providers for COVID-19 vaccine information. Those with more (versus less) exposure risk (aOR 1.14, 95% CI [1.01, 1.26]), COVID-19 susceptibility (aOR 1.17, 95% CI [1.05, 1.30]), no insurance (aOR 1.52, 95% CI [1.37, 1.70]), and no regular healthcare provider (aOR 1.32, 95% CI [1.19, 1.46]) were more likely to test infrequently. Those with more (versus less) exposure risk, susceptibility, and barriers to healthcare were less likely to have purchased SARS-CoV-2 at-home tests and to have requested freely available tests from covidtests.gov. Conclusions: Initiatives to increase testing uptake should prioritize reaching those with greater risk of SARS-CoV-2 exposure, susceptibility to severe COVID-19, and for those with barriers to healthcare access.