Takkinsatian P.Wannaphahoon K.Upapan P.Senawong S.Prommalikit O.Mahidol University2024-06-132024-06-132024-06-01Singapore medical journal Vol.65 No.6 (2024) , 340-347https://repository.li.mahidol.ac.th/handle/20.500.14594/98734INTRODUCTION: During the last decade, measles has become an important re-emerging disease in Thailand. The objective of this study was to measure measles seroprevalence and its influencing factors so as to plan an improved vaccination programme. METHODS: A total of 600 participants aged between 9 months and 50 years were divided into seven groups representing birth cohorts that experienced different measles vaccination policies. Participants' blood samples were obtained to measure measles immunoglobulin G (IgG) levels. RESULTS: None of the participants in the age group of 9 months had measles IgG levels beyond a protective level. Participants in the age groups 2.5, 5-15, 16-29, 30-33, 34-40 and 41-50 years had 82% (95% confidence interval [CI] 73.3-90.7), 50% (95% CI 36.1-63.9), 52% (95% CI 42.3-62.7), 70% (95% CI 61.1-78.9), 88.8% (95% CI 84.1-93.5) and 98.8% (95% CI 96.4-100.0) measles seropositivity, respectively. The study did not find any significant factors affecting measles seropositivity. CONCLUSION: Individuals aged 15-34 years are vulnerable to measles infections. Supplementary vaccination should be encouraged in special situations, including postexposure prophylaxis for young adults during an outbreak and for high-risk occupations such as healthcare personnel.MedicineArticleSCOPUS10.11622/smedj.20220582-s2.0-851374101362737593535651287