Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel (RECOVER) Study: Protocol for a multi-site longitudinal cohort.

Background Workers critical to emergency response and continuity of essential services during the coronavirus disease 2019 (COVID-19) pandemic are at a disproportionally high risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Prospective cohort studies are needed to enhance understanding the incidence of symptomatic and asymptomatic SARS-CoV-2 infection, identifying risk factors, assessing clinical outcomes, and determining the effectiveness of vaccination. Objective The Research on the Epidemiology of SARS-CoV-2 in Essential Response personnel (RECOVER) prospective cohort study was designed to estimate the incidence of symptomatic and asymptomatic SARS-CoV-2 infection, examine risk factors for infection and clinical spectrum of illness, and assess effectiveness of vaccination among essential workers. Methods The RECOVER multi-site network was initiated in August 2020 and aims to enroll 3,000 healthcare personnel (HCP), first responders, and other essential and frontline workers (EFW) in six U.S. locations. Data on participant demographics, medical history, and vaccination history are collected at baseline and throughout the study. Active surveillance for symptoms of COVID-19-like illness (CLI), accessing medical care, and symptom duration are ascertained by text messages, e-mails, and direct participant or medical record reports. Participants self-collect a mid-turbinate nasal swab weekly, regardless of symptoms, and two additional respiratory specimens at the onset of CLI. Blood is collected upon enrollment, every three months, approximately 28 days after a reverse-transcription-polymerase-chain-reaction (RT-PCR)-confirmed SARS-CoV-2 infection, and 14-28 days after a dose of any COVID-19 vaccine. Beginning in February 2021, household members of RT-PCR-confirmed participants self-collect mid-turbinate nasal swabs daily for ten days. Results The study observation period began in August 2020 and is currently expected to continue through spring 2022. There are 2,623 actively enrolled RECOVER participants, including 252 participants who were found to be positive for SARS-CoV-2 by RT-PCR. Enrollment is ongoing at three of six study site locations. Conclusions Data collected through the cohort are expected to provide important public health information for essential workers at high risk for occupational exposure to SARS-CoV-2 and allow early evaluation of COVID-19 vaccine effectiveness. International registered report DERR1-10.2196/31574.