Present anti-measles immunity in Jordan.

The immunity of adults and the prevalence of measles was determined in order to evaluate the adequacy of current measles vaccination policy in Jordan. A total of 307 sera, collected from adults aged 18--40 years, were tested for anti-measles antibodies by ELISA technique. The overall prevalence of anti-measles antibodies was 94.8% and there was no significant difference in the seropositivity rate between males (95.7%) and females (94%). Of the tested adults, 71% were vaccinated and 29% escaped vaccination. In Jordan, measles outbreaks occur periodically and predominantly attack children aged 5--14 years. Our data support introducing the compulsory MMR vaccine in the year 2000 to improve the vaccination coverage of measles; since the optional single dose vaccination has not interrupted the circulation of the measles virus. A second dose of MMR vaccine could be offered to Jordanians either at school entry or at the age of 11--12 years, based on the outcome of the compulsory single dose of MMR vaccine.