Diphtheria morbidity in the Czech part of former Czechoslovakia showed a continuous downward trend between 1946 and 1974. Afterwards, sporadic cases of diphtheria were reported in some years. Compulsory vaccination against diphtheria was started in 1946 with a monovaccine, later replaced by bivaccine DiTe. Since 1958, newborns have been vaccinated with DiTePe vaccine. As many as 98% to 100% of the population of age groups under 50 years likely to have been vaccinated have antibody levels > 0.01 lU/ml. About 83% to 88% of the older age groups who represent a naturally immunized population have antibodies as well. This immune status excludes the possibility that diphtheria could spread massively if accidentally imported into the Czech Republic.

Center of Epidemiology and Microbiology National Institute of Public Health Prague Czech Republic