A national prospective cohort study of SARS/COV2 pandemic outcomes in the U.S.: The CHASING COVID Cohort


McKaylee Robertson, Sarah Kulkarni, Amanda Berry, Chloe Mirzayi, Andrew R Maroko, Rebecca Zimba, Drew Westmoreland, Christian Grov, Angela Parcesepe, Levi Waldron, Denis Nash


The Chasing COVID Cohort (C3) study is a US-based, geographically and socio-demographically diverse sample of adults (18 and older) enrolled into a prospective cohort study during the upswing of the U.S. COVID-19 pandemic.


We used internet-based strategies to enroll C3 participants beginning March 28th, 2020. Following baseline questionnaire completion, study participants will be contacted monthly (for 6 months) to complete assessments of engagement in non-pharmaceutical interventions (e.g., use of cloth masks, avoiding large gatherings); COVID-19 symptoms; SARS/COV2 testing and diagnosis; hospitalizations; healthcare access; and uptake of health messaging. Dried blood spot (DBS) specimens will be collected at the first follow-up assessment (last week of April 2020) and at month 3 (last week of June 2020) and stored until a validated serologic test is available.


As of April 20, 2020, the number of people that completed the baseline survey and provided contact information for follow-up was 7,070. Participants resided in all 50 US states, the District of Columbia, Puerto Rico, and Guam. At least 24% of participants were frontline workers (healthcare and other essential workers). Twenty-three percent (23%) were 60+ years, 24% were Black or Hispanic, 52% were men, and 52% were currently employed. Nearly 20% reported recent COVID-like symptoms (cough, fever or shortness of breath) and a high proportion reported engaging in non-pharmaceutical interventions that reduce SARS/COV2 spread (93% avoided groups >20, 58% wore masks; 73% quarantined). More than half (54%) had higher risk for severe COVID-19 illness should they become infected with SARS/COV2 based on age, underlying health conditions (e.g., chronic lung disease), or daily smoking.


A geographically and socio-demographically diverse group of participants was rapidly enrolled in the C3 during the upswing of the SARS/COV2 pandemic. Strengths of the C3 include the potential for direct observation of, and risk factors for, seroconversion and incident COVID disease (among those with or without antibodies to SARS/COV2) in areas of active transmission.

Overview of SARS-COV-2 studies seroprevalence in context of the worldwide  COVID-19 pandemie. You can register a study here: Contribute
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