SARS-CoV-2 Cluster among Security Guards, Chennai, Tamil Nadu, India, June–July 2020

ABSTRACT

Congregate work settings are at increased risk for SARS?CoV?2 transmission and predispose to super spreader events. We investigated a COVID?19 outbreak among security guards to identify the risk factors and propose recommendations. We defined a COVID?19 case as a laboratory?confirmed reverse transcription polymerase chain reaction?positive case. We traced the contacts actively and described the cases by time, place, and person. We conducted a case–control study and collected data on potential exposures. We identified 20 (27%) COVID?19 cases among 75 security guards. Among the cases, 17 (85%) were male and 12 (60%) were symptomatic. We recruited all the 20 COVID?19?confirmed cases and 55 COVID?19?negative controls for the case–control study. SARS?CoV?2 infection was higher among those had high?risk exposure (60%, [12/20]) than who did not (16%, [9/55], adjusted odds ratio = 5.9, 95% confidence interval = 1.6?22.1). Having had high?risk exposure with COVID?19 cases led to COVID?19 outbreak among the security guards. We recommended avoiding the activities predisposed to high?risk exposure.