Identification of Presymptomatic and Asymptomatic Cases Using Cohort-Based Testing Approaches at a Large Correctional Facility—Chicago, Illinois, USA, May 2020
Ashutosh Wadhwa, Kiva A. Fisher, Rachel Silver, Mitsuki Koh, Melissa Arons, David A. Miller, Anne F McIntyre, Jeni Vuong, Kaylee Kim, Mayuko Takamiya, Alison M. Binder, Jacqueline E. Tate, Paige A. Armstrong, Stéphanie Black, Connie Mennella, Rebecca Levin, Jane Gubser, Bridgette L. Jones, Sharon Welbel, Patrick K. Moonan, Kathryn Curran, Isaac Ghinai, Reena H. Doshi, Chad Zawitz
Abstract
BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to cause significant morbidity and mortality worldwide. Correctional and detention facilities are at high risk of experiencing outbreaks. We aimed to evaluate cohort-based testing among detained persons exposed to laboratory-confirmed cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in order to identify presymptomatic and asymptomatic cases. METHODS: During 1-19 May 2020, 2 testing strategies were implemented in 12 tiers or housing units of the Cook County Jail, Chicago, Illinois. Detained persons were approached to participate in serial testing (n = 137) and offered tests at 3 time points over 14 days (day 1, days 3-5, and days 13-14). The second group was offered a single test and interview at the end of a 14-day quarantine period (day 14 group) (n = 87). RESULTS: 224 detained persons were approached for participation and, of these, 194 (87%) participated in ≥1 interview and 172 (77%) had ≥1 test. Of the 172 tested, 19 were positive for SARS-CoV-2. In the serial testing group, 17 (89%) new cases were detected, 16 (84%) on day 1, 1 (5%) on days 3-5, and none on days 13-14; in the day 14 group, 2 (11%) cases were identified. More than half (12/19; 63%) of the newly identified cases were presymptomatic or asymptomatic. CONCLUSIONS: Our findings highlight the utility of cohort-based testing promptly after initiating quarantine within a housing tier. Cohort-based testing efforts identified new SARS-CoV-2 asymptomatic and presymptomatic infections that may have been missed by symptom screening alone.