Seroprevalence of measles and varicella in healthcare workers in Chonburi province, Thailand between October 2022 and January 2023

IntroductionHealth care workers (HCWs) face the risk of contracting and transmitting vaccine-preventable infectious diseases (VPDs). Therefore, it is crucial to evaluate the immune status of HCWs against certain VPDs, such as measles and varicella zoster virus (VZV). This study aimed to determine age-specific seropositivity rates of anti-measles and anti-VZV IgG in HCWs working in Chonburi province, Thailand, and to develop a measles and varicella vaccination policy for Thai HCWs. MethodsA total of 266 HCWs in Chonburi Province, Thailand, were enrolled in this study between October 2022 and January 2023. Participants were divided into six age groups: 21-30, 31-40, 41-50, 51-60, 61-70, and >70 years. Anti-measles and anti-VZV IgG levels were evaluated using commercial ELISA kits (EUROIMMUN, Lubeck, Germany). ResultsThe overall seropositivity rates for measles and varicella were 85.0% and 81.2%, respectively. The lowest seropositivity rates for both measles and varicella were found among the 21-30-year-old group. Furthermore, seropositivity rates increased with age, reaching 100% among people over the age of 60 years. ConclusionsTo prevent measles and VZV outbreaks in HCWs, it is crucial to implement catch-up measles and varicella vaccination programs, particularly among HCWs younger than 30 years of age.