Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel (RECOVER): Protocol for a Multisite Longitudinal Cohort Study
Authors: Edwards Laura J , Fowlkes Ashley L , Wesley Meredith G , Kuntz Jennifer L , Odean Marilyn J , Caban-Martinez Alberto J , Dunnigan Kayan , Phillips Andrew L , Grant Lauren , Herring Meghan K , Groom Holly C , Respet Karley , Beitel Shawn , Zunie Tnelda , Hegmann Kurt T , Kumar Archana , Joseph Gregory , Poe Brandon , Louzado-Feliciano Paola , Smith Michael E , Thiese Matthew S , Schaefer-Solle Natasha , Yoo Young M , Silvera Carlos A , Mayo Lamberte Julie , Mak Josephine , McDonald L Clifford , Stuckey Matthew J , Kutty Preeta , Arvay Melissa L , Yoon Sarang K , Tyner Harmony L , Burgess Jefferey L , Hunt Danielle Rentz , Meece Jennifer , Gaglani Manjusha , Naleway Allison L , Thompson Mark G 
Published: October 2021

Background
Workers critical to emergency response and continuity of essential services during the COVID-19 pandemic are at a disproportionally high risk of SARS-CoV-2 infection. Prospective cohort studies are needed for enhancing the understanding of the incidence of symptomatic and asymptomatic SARS-CoV-2 infections, 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 infections, examine the risk factors for infection and clinical spectrum of illness, and assess the effectiveness of vaccination among essential workers.

Methods
The RECOVER multisite network was initiated in August 2020 and aims to enroll 3000 health care personnel (HCP), first responders, and other essential and frontline workers (EFWs) at 6 US locations. Data on participant demographics, medical history, and vaccination history are collected at baseline and throughout the study. Active surveillance for the symptoms of COVID-19–like illness (CLI), access of medical care, and symptom duration is performed by text messages, emails, and direct participant or medical record reports. Participants self-collect a mid-turbinate nasal swab weekly, regardless of symptoms, and 2 additional respiratory specimens at the onset of CLI. Blood is collected upon enrollment, every 3 months, approximately 28 days after a reverse transcription polymerase chain reaction (RT-PCR)–confirmed SARS-CoV-2 infection, and 14 to 28 days after a dose of any COVID-19 vaccine. From February 2021, household members of RT-PCR–confirmed participants are self-collecting mid-turbinate nasal swabs daily for 10 days.

Results
The study observation period began in August 2020 and is expected to continue through spring 2022. There are 2623 actively enrolled RECOVER participants, including 280 participants who have been found to be positive for SARS-CoV-2 by RT-PCR. Enrollment is ongoing at 3 of the 6 study sites.

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 Identifier (IRRID)
DERR1-10.2196/31574