Five children aged five to 15 years contracted tetanus in Finland between 1969 and 1985, together with 101 adults. Four of the five had been adequately immunized against tetanus. The clinical picture of tetanus was mild or moderate, and none of the children needed respirator treatment. Epilepsy, meningitis and psychogenic symptoms were considered in the differential diagnosis. The course of tetanus in immunized patients is atypical and often benign, but the diagnosis is problematic--in contrast to affected children in developing countries, whose populations are not adequately immunized and where neonatal tetanus is common and often fatal.