Correlation of Herd Immunity to Measles Vaccination Rate and Disease Incidence

Abstract

Background: Measles is one of the most contagious diseases faced by humans. Despite considerable progress, measles remains one of the leading global causes of death among children. Methods and Results: The seroprevalence of antibodies against measles in Kosovo was determined with a serological survey of measles. In total, 768 participants aged between 3 days and 45 years of both sexes were included. Enzyme-linked immunosorbent assay results revealed total seropositivity of 74.5% (95% CI: 0.70–0.88) among participants. Those in the unvaccinated 0–1.9-year age group had the lowest seropositivity (33.2%). The 2–6-year age group, which received one dose of the vaccine, had higher seropositivity (78.6%) than the youngest group. The 8–17-year age group, which received two doses of the measles vaccine, had significantly higher seropositivity (91.3%) than the 2–6-year age group. The highest level of seropositivity (93.4%) was observed in the 18–45-year age group. An analysis of sex-specific IgG antigen levels indicated that female participants had significantly higher seropositivity than male participants (P<0.01). Conclusion: The seroprevalence of measles antibodies in Kosovo has not yet reached the required 95% threshold, and the threat of a possible measles epidemic exists. An immunization strategy that targets vulnerable groups and the entire population is required.