Tuberculosis notwithstanding BCG vaccination.

In a series of 176 patients, 40 children (23%) developed tuberculosis notwithstanding BCG vaccination. The type and severity of the disease in this group were similar to those of the larger series of which this group was a part. However, BCG vaccination appeared to diminish the incidence of dissemination, especially tuberculous meningitis, and the number of deaths. The 40% incidence of tuberculous contacts probably indicates heavy exposure to infection. BCG offers a modicum of protection which the vulnerable should not be denied, but its use should not lead to complacency--the potency of vaccines and the technique of vaccination require constant surveillance. Case finding remains a priority and even BCG-vaccinated patients should be treated for tuberculosis when this is suspected.