Measles seroprevalence in izmir with special emphasis on measles vaccination policy for Turkey

Background: Measles outbreaks seem to occur every 2- to 3-year intervals in Turkey. However, seroepidemiological studies are limited. Knowing the prevalence of measles susceptibility as measured either by serologic markers of immunity or surveys of vaccination coverage is an important tool to assess the risk for measles outbreaks. Methods: In order to determine the seroprevalence of measles antibodies among a 1 to 29-year-old population in Izmir (Turkey) and to develop the best vaccination policy for measles, a total of 600 people aged from 1 to 29 were selected for the study with cluster sampling. The information on sociodemographic characteristics, vaccination status and measles history was gathered for each participant. Measles-specific IgG antibodies were screened qualitatively by using microenzyme immune assay for 595 subjects. Results: Of the 595 participants screened for the measles antibodies, 56 (9.4%) were seronegative. The proportion of the susceptible individuals in the age groups of 1-4, 5-9, 10-14, 15-19 and 20-29 was 20.0, 10.4, 6.0, 10.3 and 3.0%, respectively. The logistic regression analysis showed that none of the independent characteristics (sex, socioeconomic status, past measles history, vaccination status) with the exception of age group, was significantly associated with measles seronegativity. Conclusion: The optimal measles vaccination policy for Turkey may be to increase vaccination coverage above 90%, to conduct a catch-up campaign covering persons aged 1-19, regardless of previous vaccination status. Another factor to consider is to adopt a routine two-dose vaccination, giving the first dose at 12-15 months of age and the second dose at school entry.