Poliomyelitis in the eastern European countries--achievements and remaining problems.
All European countries adopted in 1984 the Regional Target 5 of Health for All 2000 aimed at the elimination of poliomyelitis. From 1991 to 1992 the number of independent states in Eastern Europe has doubled (from 9 to 20). Physical and social environment, life-styles of the population, as well as public health and medical services in the majority of these states began to deteriorate due to political and economic crises. This led to increases in incidence of some infectious diseases, notably diphtheria and poliomyelitis. The incidence of poliomyelitis has risen in the Caucasus, Middle Asia, and Balkans, thus indicating new or ongoing epidemics in these areas. The highest incidence of the disease in the Balkan states was observed in 1991 (74 cases), in the Caucasian states in 1990 (251 cases), and in Middle Asia in 1991 (140 cases). There were two main reasons for the epidemics: (1) decreasing immunization coverage and (2) poor surveillance of poliomyelitis (late reporting, low sensitivity, etc.). Effective surveillance for cases of acute flaccid paralysis as the key strategy for guiding immunization policies is not yet organized in the overwhelming majority of states. Affected countries do not have national immunization programmes formulated according to the WHO/EPI standard. Difficulties in production or purchasing of vaccines, lack of competence and managerial skills, and inadequate political and financial support may play a negative role in eliminating poliomyelitis. However, even under these unfavorable conditions, supplementary immunization activities, such as appropriate outbreak response and mass immunization campaigns, helped to reduce the incidence of the disease in 1991 four- to eight-fold compared to the previous period.