o:2866 Pneumonia in healthcare workers during a COVID-19 outbreak at a cardiovascular hospitals en OBJECTIVES: During the coronavirus disease 2019 (COVID-19) pandemic, healthcare workers (HCWs) have been at high risk of infection. This study investigated clinical and treatment characteristics of infected HCWs at a cardiovascular hospital. METHODS: This retrospective study was conducted at a tertiary cardiovascular hospital and included HCWs with confirmed COVID-19. Subjects completed a questionnaire on health status, symptoms, admission to hospital and treatment. Vaccination status against tuberculosis, hepatitis B and seasonal influenza was assessed. Pneumonia was defined as ground glass opacifications (GGOs) and consolidations on computed tomography (CT). RESULTS: This study included 107 HCWs with confirmed COVID-19, representing 15% of all HCWs (n = 726) at the study hospital. Most of the confirmed cases worked in the cardiac surgery department, the anaesthesiology and intensive care medicine department, and the postoperative ward [74/107 (69%)]. A substantial number of infected HCWs were asymptomatic [31 (28.9%)], and 38 (35.5%) were admitted to hospital. The mean standard deviation length of hospital stay was 8.1 5.6 days. Seventy-five of 107 (70.1%) confirmed cases had been vaccinated against seasonal influenza. Pneumonia with GGOs and consolidations on CT occurred in 25 of 107 (23.4%) HCWs, with 14 (13.1%) cases of bilateral involvement. On multivariate logistic regression analysis including characteristics known to be associated with poorer outcomes in COVID-19 (i.e. obesity, diabetes mellitus, coronary artery disease, cerebrovascular disease, current smoking, heart failure, seasonal influenza immunization), only seasonal influenza immunization remained an independent predictor of the occurrence of bilateral pneumonia (odds ratio 0.207, 95% confidence interval 0.050–0.847; P = 0.029). CONCLUSIONS: The association found between seasonal influenza immunization and less-aggressive COVID-19 pneumonia may support the implementation of preventive measures to reduce the global burden of COVID-19. Key words: coronavirus, pneumonia, influenza, immunization 91552100 125419529 1552101 1201-9712 1552099 10.1016/j.ijid.2020.11.156 2023-09-29T11:49:35.922Z 44 yes 46 Ivan Ilić 63512841 0000-0002-5110-7102 2021 46 Marina Zdravković 104914441 2021 46 Stefan Timčić 104913929 0000-0002-9278-9701 2021 46 Dragana Unić Stojanović 19204199 0000-0002-7066-6292 2021 46 Milovan Bojić 1394535 0000-0002-0051-041X 2021 46 Goran Lončar 29116519 0000-0001-8553-683X 2021 application/pdf 472437 https://unilib.phaidrabg.rs/o:2866 no yes 18 70 616.24-002:616.989 92000001 71A11 International Journal of Infectious Diseases 103 188 193 2021