[Determination of antitetanus antibodies. Methodological and epidemiological studies].

We weighed the situation of tetanus immunity in a population sample of the province of Pavia in which both sexes and all age groups were represented. We carried out the survey performing the indirect haemagglutination test with turkey red cells. In each age groups the checked subjects have been classified in three different tetanus antibodies concentration levels: under 0.01 U/ml, between 0.01 and 0.1 U/ml, above 0.1 U/ml. The method we used is easy to perform and has a good reproducibility. The survey points out the good protection against tetanus in age classes under twenty years and the possibility of discovering districts where ineffective immunization methods are performed.