[Duration of protection after BCG vaccination with the 1331 Copenhagen strain (author's transl)].

Children vaccinated in 1975 with different doses of BCG were tested when they were 2 1/2 years old by means of the tine test or, if negative, the tuberculin test at 1 : 100. Of those children who, according to present-day view, had been satisfactorily immunised, 34 of 42 still showed a tuberculin allergy after 2 1/2 years, of those unsatisfactorily vaccinated only 23 of 38. In addition it was found that, contrary to general teaching, positive tuberculin allergy is possible even without scar after a BCG vaccination with the Copenhagen strain (6 of 13). The need of revaccination of tuberculin-negative persons is stressed.