BACKGROUND: Healthcare-associated coronavirus disease 2019 (COVID-19) has significant implications for patients, their companions, and healthcare workers (HCWs). Controlling transmission in healthcare settings is critical for reducing COVID-19 mortality. AIM: We aimed to describe the epidemiology and characteristics of healthcare-associated COVID-19 outbreaks and outbreak-related cases. METHODS: We retrospectively analyzed the investigation data of each healthcare-associated outbreak that occurred between 15th January 2020 and 31st July 2021 in Taiwan. We categorized the confirmed outbreak-associated cases as HCW, patient companion, and patient, and compared the characteristics of the confirmed cases among these categories. FINDINGS: A total of 54 healthcare-associated COVID-19 outbreaks including 512 confirmed cases were reported. The median number of affected cases per outbreak was 6 (interquartile range [IQR], 2–12), and the median outbreak duration was 12 days (IQR, 4.3–17.0). Only 5.7% and 0.2% of all confirmed cases had partial and full vaccinations, respectively. Most of the outbreaks (90%, 48/54) occurred in May and June 2021. HCW cases accounted for 19.5%, companion cases for 41.2%, and patients for 39.3% of the total cases. Patients were significantly older (72 years; IQR, 61–83) and had higher 30-day all-cause mortality (37.4%) than HCWs (41 years; IQR, 28–58; 0%) and companions (52 years; IQR, 42–62; 1%). CONCLUSION: Healthcare-associated COVID-19 outbreaks have a critical impact on patients. Nevertheless, two-thirds of cases in the healthcare-associated outbreaks in this study comprised HCWs and companions. To effectively mitigate COVID-19 transmission in healthcare settings, multi-pronged infection prevention and control measures should be implemented and tailored for these three groups.
Healthcare-associated COVID-19 outbreaks: a nationwide population-based cohort study