Measles Immunity and Associated Factors Among Healthcare Workers in Bandar Abbas Following the 2025 Outbreak: A...

Measles is a highly contagious viral infection that poses significant risks to healthcare workers (HCWs) during outbreaks and can lead to nosocomial transmission. Despite vaccination programmes, immunity gaps persist, as seen in the 2025 Bandar Abbas, Iran, outbreak, necessitating seroprevalence assessments among HCWs in vulnerable regions. To assess measles immunity seroprevalence among Bandar Abbas HCWs following the 2025 outbreak and examine associated demographic factors (age, sex).

This cross-sectional study surveyed 175 HCWs from three hospitals in Bandar Abbas using convenience sampling (January-April 2025). Data included questionnaires on demographics and vaccination, as well as ELISA-based serological IgG testing. Immunity was categorised as positive or not positive (negative/equivocal). Analyses employed Spearman's correlation, the Mann-Whitney U test, the Chi-square test and logistic regression (p < 0.05).

Participants had a mean age of 31.54 ± 7.42 years, and 62.9% were female. All reported prior measles vaccination. Seroprevalence of positive immunity was 74.9%, while 25.1% were not positive. Age showed a significant positive correlation with IgG levels (rho = 0.360, p < 0.001) and with immunity status (U = 1763.500, p < 0.001). Logistic regression revealed that each additional year of age increased the odds of positive immunity by 14.3% (OR = 1.143, 95% CI 1.061-1.232, p < 0.001). There was no significant association with sex (p = 0.813). Vaccination history could not be analysed due to insufficient variation.

Notable immunity gaps in Bandar Abbas HCWs, especially among younger staff, underscore the need for targeted screening, boosters and enhanced infection control measures.