A new report on a Washington state COVID-19 surveillance and response system underscores the value of workplace investigations as a disease prevention and management strategy.

The system was established by public health officials in Seattle and King County in May 2020. Based on findings from a June 15-Nov. 15, 2020 study of the response system, researchers concluded that “workplace investigations can enhance the effectiveness of contact tracing and identification of workplace outbreaks, which can inform the implementation of strategies to prevent the spread of COVID-19.”

Researchers also found that workplace surveillance and investigations offer an opportunity to provide guidance on preventing exposures, facilitate employee access to vaccination, and strengthen collaboration between public health officials and employers.

When we asked Christopher Jankosky, M.D., M.P.H., WorkCare’s senior vice president, clinical operations, to comment on the findings, he referred to one of the study’s four stated limitations: “Whereas the number of cases associated with workplace outbreaks as a proportion of the total number of cases in King County (5.0 percent) was similar to that reported in Wisconsin (5.2 percent), it was less than that reported in Utah (12 percent), suggesting potential underreporting of workplace-associated cases.”

Dr. Jankosky noted the following:

• Although some studies reveal workplace outbreaks may represent only 5 percent of the total number of community cases, workplace-associated cases are likely underreported.
• Workplace investigations are important for informing the implementation of strategies to prevent the spread of COVID-19.
• The COVID Delta variant, which is likely to become dominant in the U.S. this summer, is more easily spread, increasing the risk for workplace-associated cases and reinforcing the need for vigilance by a company’s occupational health and safety leadership team.
• Lessons gleaned from COVID-19 workplace investigations may be applicable to overall disease prevention and management solutions in the workplace.

More About the Report

During the study period, 2,881 workplaces in King County reported at least one case of COVID-19. Among 1,305 workplaces (45 percent of investigated workplaces), 524 met the definition of a workplace outbreak (defined as two or more confirmed cases). Among 306 workplaces with complete data, an average of 4.4 employee COVID-19 cases were identified per outbreak, with an average attack rate among employees of 17.5 percent.

A ranking system was established to prioritize workplace investigations as high, medium or low priority. The system was based on workplace factors observed to be associated with increased COVID-19 spread and workforce features associated with severe disease outcomes. This approach helped with the deployment of investigative techniques at a time when resources were limited.

According to the report, high-priority investigations were more likely to have two or more cases among employees, two or more cases not previously linked to the workplace, or two or more exposed workplace contacts not previously elicited during case interviews. Researchers concluded that improved understanding of occupational risk factors for SARS-CoV-2 infection in workplaces could be used to further refine prioritization, in turn reducing community transmission through rapid isolation and quarantine of workplace-associated cases and contacts.

To learn more about WorkCare’s COVID-19 response solutions and infectious disease management capabilities, visit our COVID-19 and Exams & Travel Medical webpages, or write to us at info@workcare.com.