[Diphtheria immunity in the German population].

In the years 1991-1993 the diphtheria antitoxin titres of the blood serum of 2404 persons living in germany was determined by means of the ELISA test. Its aim was to to get an idea of the population's protection given by vaccination against diphtheria. It became evident that the average protection given by vaccination against diphtheria was on the decrease as people grew older. Thus only 3.8% of the 2-5-year olds did not have any protection given by vaccination (antitoxin titre < 0.01 IU/ml). The same was true for approximately 25% of the examined persons who were older than 30. Less than 10% of these persons had a thorough protection given by vaccination/(antitoxin titre > 0.1 IU/ml). In the age group of the 51-60-year olds better immunological protection than expected was found, which could be ascribed to the fact that there was a natural immunigation during the last wide-spread diphtheria epidemic in germany in the 'forties. Another aspect of this result could be a better motivation for-diphtheria vaccination in this age group. Furthermore, it was noticed that the average diphtheria antitoxin titres of women in all age groups were below those of men. In view of the great percentage of the adult population which is not sufficiently protected against diphtheria, it appears necessary to provide for more information of this population group to stimulate and motivate them to care for better protection by vaccination.