Seroepidemiological study on prevalence of measles antibodies in Urawa City.

To obtain a precise seroepidemiological understanding of measles antibodies, we analysed hemagglutination inhibition (HI) and neutralizing test (NT) antibodies in different age groups in Urawa City. We examined 1591 serum samples collected from subjects aged from zero day to 95 years. Of these 1591 samples, 1094 were HI antibody positive with a positive rate of 68.7%. Mean HI antibody titer by age was from 2(4.0 +/- 0.82) to 2(5.4 +/- 1.43). Of the 497 samples which were HI antibody negative, 419 were NT positive. HI antibody positive rate and mean antibody titer were decreased at ages 6 to 12 months, and then increased with age. Approximately 5% of school children aged 6 to 15 years were not immune status. The key issue for measles eradication is how to immunize this population.