Many Brief Encounters: COVID-19 in a Vermont Correctional Officer, 2020

This report describes a case from the summer of 2020, early in the COVID-19 pandemic.

On August 11, 2020, the Vermont Department of Health (VDH) received a report of a confirmed COVID-19 case in a 20-year-old male correctional officer. On July 28 he had had many brief encounters with six incarcerated people whose test results were still pending.

What happened

• July 28: six people arrived from an out-of-state correctional facility with no symptoms and were placed in a quarantine unit. Under Vermont Department of Corrections policy, they were swabbed on arrival and tested by RT-PCR at the state laboratory.
• July 29: all six tested positive. VDH and the Department of Corrections traced contacts and, using video footage, concluded that the officer did not meet VDH's definition of a close contact, being within 6 feet of an infectious person for 15 minutes or more in a row, so he kept working.
• August 4: at the end of his shift he lost his sense of smell and taste and developed muscle aches, runny nose, cough, shortness of breath, headache, loss of appetite and stomach symptoms. From August 5 he stayed home.
• August 11: a sample taken August 5 came back positive. His two contacts outside work did not get sick.

He had no other known exposures outside work and had not left Vermont in the two weeks before he fell ill. COVID-19 was relatively rare in his county and the prison's county at the time (20 cases per 100,000 people). The evidence pointed to his work: at least one of the six people, none of whom had symptoms, likely infected him during brief encounters seven days before his illness began.

Adding up the minutes

VDH and prison staff reviewed video from July 28 and the officer's standard duties to estimate his contact with the six infected people during his 8-hour shift:

He was never within 6 feet of an infected person for 15 minutes in a row, but his roughly one-minute encounters added up to more than 15 minutes. The six people wore cloth masks for most encounters outside their cells but not during several at cell doorways or in the recreation room. The officer wore a cloth mask, gown and goggles each time, and gloves most of the time. The 17-minute figure is an informed estimate, and some encounters may have been missed.

Of seven employees whose exposures did meet the close-contact definition, one tested positive. Of 13 employees, including this officer, whose exposures did not, only he did.

What it means

Data to define "close contact" precisely were limited, but 15 minutes of close exposure was widely used as a working definition for contact tracing. Other factors also matter: how close people are, how long, whether the infected person has symptoms or is likely to produce respiratory aerosols, and ventilation and crowding. Contact tracing aims to find people with higher-risk exposures to guide quarantine and work decisions. Here, the first assessment found no close contact, but a detailed look at video showed the brief exposures added up to more than 15 minutes. In prisons, where staff and incarcerated people must often come within 6 feet of each other, the authors urged health officials to consider the risk of cumulative exposure time.

Sources

• Pringle JC, Leikauskas J, Ransom-Kelley S, et al. COVID-19 in a Correctional Facility Employee Following Multiple Brief Exposures to Persons with COVID-19 — Vermont, July–August 2020. MMWR Morb Mortal Wkly Rep 69(43); posted as an Early Release on October 21, 2020. https://www.cdc.gov/mmwr/volumes/69/wr/mm6943e1.htm