COVID-19 Outbreak Among Employees at a Meat Processing Facility - South Dakota, March-April 2020

Abstract

On March 24, 2020, the South Dakota Department of Health (SDDOH) was notified of a case of coronavirus disease 2019 (COVID-19) in an employee at a meat processing facility (facility A) and initiated an investigation to isolate the employee and identify and quarantine contacts. On April 2, when 19 cases had been confirmed among facility A employees, enhanced testing for SARS-CoV-2, the virus that causes COVID-19, was implemented, so that any employee with a COVID-19-compatible sign or symptom (e.g., fever, cough, or shortness of breath) could receive a test from a local health care facility. By April 11, 369 COVID-19 cases had been confirmed among facility A employees; on April 12, facility A began a phased closure* and did not reopen during the period of investigation (March 16-April 25, 2020). At the request of SDDOH, a CDC team arrived on April 15 to assist with the investigation. During March 16-April 25, a total of 929 (25.6%) laboratory-confirmed COVID-19 cases were diagnosed among 3,635 facility A employees. At the outbreak's peak, an average of 67 cases per day occurred. An additional 210 (8.7%) cases were identified among 2,403 contacts of employees with diagnosed COVID-19. Overall, 48 COVID-19 patients were hospitalized, including 39 employees and nine contacts. Two employees died; no contacts died. Attack rates were highest among department-groups where employees tended to work in proximity (i.e., <6 feet [2 meters]) to one another on the production line. Cases among employees and their contacts declined to approximately 10 per day within 7 days of facility closure. SARS-CoV-2 can spread rapidly in meat processing facilities because of the close proximity of workstations and prolonged contact between employees (1,2). Facilities can reduce this risk by implementing a robust mitigation program, including engineering and administrative controls, consistent with published guidelines (1).

FIGURE

Confirmed COVID-19 cases among employees at a meat processing facility (n = 929), their contacts (n = 210), and community residents (n = 1,086) and facility mitigation strategies, by date of illness onset^, (N = 2,225) — South Dakota, February 24−April 25, 2020 Abbreviation: COVID-19 = coronavirus disease 2019. * A person who resided in one of the two counties that make up the city in which facility A is located who was neither an employee of facility A nor a contact of an employee. ^† Beginning April 12, the facility did not slaughter any more animals. During April 12–14, the facility processed animals that had already been slaughtered, shipped finished product, and progressively closed departments. From April 15 onward, only staff members necessary for maintenance, cleaning, and sanitization of the facility, transportation of remaining product, and implementation of COVID-19 prevention activities reported to work. ^§ The date COVID-19–compatible symptoms first appeared or, if no symptom onset date was documented during the investigation, specimen collection date. For asymptomatic persons, SARS-CoV-2 specimen collection date is reported. ^¶ During February 24–March 14, 11 community residents had COVID-19 illness onset.