The 2001 serological survey in the Czech Republic--diphtheria.

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.