Outbreaks of COVID-19 among healthcare personnel in a U. S. veterans administration health care system site, June and August 2023

Background Occupational COVID-19 remains a challenge among healthcare personnel (HCP). Methods This study documents three COVID-19 outbreaks that occurred among vaccinated HCP within a single health care system (HCS) in California, USA in June and August 2023. The Employee Health (EH) unit for the HCS conducted surveillance with structured interviews, identifying outbreaks in real-time. Results In June, 10 of 25 staff (40%) at a rural outpatient clinic that serves the HCS contracted COVID-19. One week later, 10 of 90 staff (11%) at a second outpatient clinic were infected, with half the cases were staff of a single close-knit team. In August, a team-building retreat of staff from the main hospital of the HCS resulted in 15 of 23 participants (65%) contracting COVID-19. The combined attack rate for these outbreaks was 25% (95% CI: 18–32%). Discussion These outbreaks, despite high vaccination rates among the employees, reveal gaps in infection control, underscoring the need for stricter masking, improved ventilation, and rigorous surveillance testing. Rapid response to outbreaks and reinforcing education on symptom-based work exclusions are critical to preventing transmission among health care workers (HCWs) and their patients.