Tuberculosis studies in Muscogee County, Georgia. Twenty-year evaluation of a community trial of BCG vaccination.

A controlled trial of BCG vaccination was conducted in 1950 in Muscogee County, Ga., and Russell County, Ala. The study population consisted of 64,136 volunteers over the age of 5 years who had satisfactory skin tests with 5 tuberculin units of purified protein derivative and whose chest photofluorograms were considered by two readers to show no significant pulmonary abnormalities. Approximately half of the nonreactors to tuberculin were vaccinated with the Tice strain of BCG by a multiple-puncture method. During a 20-year period of follow-up, 207 cases of tuberculosis were identified among the persons who had been tuberculin reactors in 1950, 36 cases were identified among the controls, and 32 cases were identified among the vaccinees. The average annual case rates per 100,000 were 47.0 for reactors, 13.4 for controls, and 12.6 for vaccinees.