Anti-tetanus toxin titers in sera of the women who gave births in 1985 and 1989 in Gipuzkoa (Basque Country, Spain).

14.9% (208/1400) of the women who gave births in 1985 and 1989 in Gipuzkoa (Basque Country, Spain), was considered to have 'protective' levels (> or = 0.01 IU/ml) of tetanus antitoxin as measured by the passive haemagglutination test. Prevalence of protective antibodies was correlated to the years when women were born: 54.7% (64/117) of those born after 1965 were considered to have 'protective' levels (> or = 0.01 IU/ml) of tetanus antitoxin in contrast to those born before 1956 [only 6.2% (21/338)]. This is considered to be due to the infant immunization campaign introduced in 1965 in the Basque Country. Thus, we conclude that the tetanus immunization campaigns in the Basque Country adult population is urgent.