Breakthrough COVID-19 infections among healthcare workers at a tertiary care hospital in Beirut: Prevalence and determinants.

Objectives: Despite mass vaccination campaigns to limit the spread of COVID-19, breakthrough infections have been reported in many countries. This raises global concern regarding the longevity and scope of vaccine-induced immunity, especially among high-risk populations such as healthcare workers (HCWs). This study aimed to examine the prevalence and predictors of breakthrough infections among HCWs at a tertiary care hospital in Beirut. Methods: A cross-sectional study was conducted among 300 HCWs from clinical and non-clinical departments. Data were collected using a structured questionnaire assessing demographics, vaccination, COVID-19 exposure, compliance with preventive measures, symptoms, and clinical outcomes with bivariate and multivariate analysis. Data were collected from participants between November and December 2023. Results: Of the 300 HCWs, 36.5% (n = 46) had breakthrough infections. In multivariate analysis, receiving more vaccine doses was associated with reduced odds of breakthrough infection (odds ratio = 0.315, 95% confidence interval: 0.116-0.855, Conclusion: Receiving more COVID-19 vaccine doses was significantly associated with a reduced likelihood of breakthrough infection among HCWs. These findings emphasize the importance of booster vaccination and support continued efforts to promote full vaccine coverage within healthcare settings.