[Level of protection against tetanus in an outpatient population].

Protection levels against tetanus toxin were estimated in 332 patients, at our Laboratory, by means of the passive haemagglutination with turkey erythrocyte test. The testing showed that the protection level decreases with age, it is higher among males in those over 30 yrs; roughly 10% of those who were not vaccinated were protected. Furthermore, it has been demonstrated that in some cases the protection level remains high even after a long period of time since the last vaccination, whereas a certain percentage of the recently vaccinated patients is not protected; consequently the effectiveness of the vaccination must be checked by measuring the antibody titers.