Public health implications of XXXX antibody levels in California.

@entity1 @entity2462
@entity2462 hemaggluttination inhibition (HI) antibody determinations were performed in 1977 on a sample of California school @entity1 and in 1977-1979 on young @entity1 who were about to be married or who were pregnant. Among the pupils, 66 per cent reported prior @entity2462 immunization; immunization history was more common in younger pupils. Seventy-seven per cent had detectable antibody, with little trend of greater seropositivity at older ages. Over 86 per cent of those with a written record of immunization had detectable antibody. There was no consistent indication of loss of seropositivity with increasing time since immunization. @entity1 immunized at 12-14 months of age tended to have a lower seropositivity rate than those immunized at older ages. Among young @entity1 , the prevalence of detectable antibody was 80-83 per cent. Comparison with data obtained in 1968-1969 indicates that @entity2462 immunization has had a marked impact on antibody levels in @entity1 but less impact on levels in teenagers and adults. The pool of @entity2462 entering secondary schools will probably not decrease soon, so that @entity2462 outbreaks may continue in high school and college-age populations. Ultimately, school entry immunization requirements should drastically curtail disease activity. In the interim, programs to immunize teenagers and young adult females must be strengthened. (Am J Public Health 1982; 72:167-172.)
