a serologic study of measles in association with the history of vaccination in 7-11 years old children in rey in 1371

201 blood samples were collected by cluster sampling from 7-11 years old children and measles antibody titer was measured by hemagglutination inhibition test. despite testing all the sera, the results were analysed on the 139 samples that had documented vaccination records and no history of measles. among 139 children 44 had received 2 doses of vaccine one dose before 12 and one after 15 months, 64 had one dose after 15 months, 29 had only one dose before 12 months and 2 had not received vaccine. the antibody titer of the first two groups had no significant difference with those that had received one vaccine dose, before the age 12 months (p<0.001). there were no significant differences in the titer of antibodies with time elapse in none of the vaccination histories. this may be due to efficacy of vaccine and also circulation of wild virus in the community. regardless of the history of vaccination, 95.5% of children had immunity to measles (titer?3). considering the results if the current strategy of vaccination implemented completely, the status of immunity would be satisfactory.