[A comparative evaluation of the effectiveness of methods for serological sampling examinations]

Blood serum samples of 3,448 schoolchildren of grades 1-10 in 35 schools of Dushanbe were examined in the passive hemagglutination test in 1988 and 1989. The proportion of persons unprotected against diphtheria and tetanus was estimated by common methods in different kinds of selective serologic survey: mass screening (43.4-83.0%), testing in selected groups reduced 2, 3 and 5 times, cluster sampling. The reduction of the groups to be examined (from 3,033 to 250 persons) was not accompanied by essential changes (t < 2) in the characteristics of mass immunity against diphtheria and tetanus. The cluster method was shown to be highly reliable also in the study of population immunity.