Factors influencing healthcare worker symptomatic respiratory infection and vaccine uptake during the post-COVID-19 pandemic period

Investigate the factors associated with symptomatic respiratory infection and uptake of seasonal SARS-CoV-2 and influenza vaccine amongst healthcare workers (HCWs). Longitudinal prospective multi-center study. Two tertiary healthcare centers in Ireland. N = 893 self-selected HCWs across all disciplines. Monthly self-reported questionnaires from September 2024 to February 2025 completed by all participants, providing infection symptoms, self-testing for COVID-19 and receipt of vaccination against SARS-CoV-2 or influenza in the preceding 30 days. Additional data collected included comorbidities, known diagnosis of Long COVID, demographic data, prior infection and vaccination status, and healthcare role. Multivariable logistic regression models assessed the factors associated with symptom development, self-testing, and vaccine uptake. Symptomatic respiratory illness was reported by n = 321 (36%) of participants during the study period, with a preexisting diagnosis of Long COVID associated with developing symptoms. Testing for COVID-19 was performed by 63% (n = 202) of symptomatic individuals, with a shorter duration since prior infection the only significant predictor of self-testing. Vaccine uptake was variable, with 37% receiving influenza and 22% receiving SARS-CoV-2 vaccination for that period. Older age and shorter interval since previous vaccine were associated with increased uptake of both vaccines, while men were more likely to be vaccinated against COVID-19. In the postpandemic period, self-reported symptomatic respiratory infections remain common amongst HCWs. The legacy of the pandemic influences this, with a preexisting diagnosis of Long COVID associated with increased symptom burden, while low vaccination rates and understanding the factors associated with this present a challenge to ongoing risk mitigation.