Characteristics of health care workers with SARS-CoV-2 at a COVID-19 hospital in Turkiye: Homologous versus heterologous vaccination

Objective: Given the limited studies on types of vaccination and infection rates among health care workers (HCWs) in T & uuml;rkiye, we analyzed the demographic, clinical, and vaccination characteristics as well as the attitudes of HCWs who have been infected with COVID-19. Methods: We retrospectively analyzed demographic and clinical data on breakthrough COVID-19 infections in HCWs from hospital surveillance data collected between April 5, 2020, and November 1, 2022. The comparison was based on four subgroups that consisted of unvaccinated, one-shot-vaccinated, homologous vaccinated, and heterologous vaccinated individuals. Participants who received various combinations of Sinovac/CoronaVac and/or BioNTech/Pfizer vaccines were compared for detection of COVID-19. Results: During a 33-month period of 744 HCWs who contracted COVID-19, women (65.3%) and nurses (28.9%) were the most affected, followed by doctors (25.8%). Of the infected HCWs, only 1.3% required hospitalization, 0.3% required ICU support, and 98.4% were outpatients. By vaccination status, 143 of the HCWs (19.2%) were unvaccinated, 292 (39.2%) were homologously vaccinated, 294 (39.5%) were heterologously vaccinated, 15 (2%) received a single shot, 206 (27.7%) received two shots, and 165 (22.2%) received three shots. All HCWs contracted COVID-19 at a mean of 134- days (range:1-539) after vaccination. While the proportions of homologously and heterologously vaccinated HCWs were similar, the time elapsed from vaccination to contracting COVID-19 varied (mean 143.4 +/- 106.7 vs.126.4 +/- 82.43 +/- 82.43 days). Conclusions: Among both outpatients and inpatients with COVID-19, women HCWs outnumbered men HCWs. HCWs who received homologous vaccination contracted COVID-19 later than those who received heterologous vaccination.