Varicella morbidity in Czechoslovakia.

Data are presented on varicella and herpes zoster morbidity notified in Czechoslovakia in the years 1970 to 1978. The notified varicella incidence is compared with serologically confirmed varicella incidence among the selected groups of children up to the age of 12 from the North-Moravia region. Comparative analysis revealed a considerable difference between the notified and serologically detected cases of varicella. The highest rate of notified varicella was recorded in children of 3 and 4 years of age, while the highest incidence of seropositive cases was detected among the 2-year-old children. The cumulative notified morbidity involved about 35% of 6-year-old and 45% of 12-year-old children, whereas specific antibodies against the varicella-zoster virus were found in about 60% of 6-year-old and 90% of 12-year-old children. The titres of virus-specific antibodies were determined by the method of indirect hemagglutination reaction. No serological methods are applicable for herpes zoster morbidity studies in the population.