IMMUNITY TO TETANUS AND DIPHTHERIA IN RURAL AFRICA

To assess the effect of the Expanded Program on Immunization (EPI) in rural Africa, blood samples were collected in two Kenyan sublocations. Serum antibodies against tetanus toroid were measured in 155 individu als 1-70 years of age. Titers greater than the protective level of 0.0 1 IU/ml were found in 47% of the population. Protection was significan tly higher in children born after the launching of the EPI (68%) and i n women who had been at childbearing age since then (69%). Significant ly lower protection was demonstrated in other age and sex-groups. The level of protection in children was equal in the two populations, wher eas protection in fertile women was significantly lower in the populat ion living a long distance from a health center. Diphtheria anti-toxin was measured in the samples from one sublocation, and 70 of 84 indivi duals (83%) had antibody levels greater than the protective level. No age or sex difference could be found, and there was no correlation bet ween response levels to diphtheria and tetanus. This implicates natura l infections as an important sourer: of diphtheria antibodies. Our fin dings demonstrate a need for better coverage of the adult population a gainst tetanus. Furthermore, diphtheria transmission still appears to take place, underscoring the importance of diphtheria vaccination of t ravelers to rural Africa.