Tuberculin Reactors in the General Population

¹ The Sunshine Sanatorium, Grand Rapids, Michigan.

Old tuberculin (0.01 mgm.) was administered intradermally to 3,627 persons and 9,969 were similarly tested with 0.1 mgm. The percentage of reactors to each dose was compared according to the decade of life. The percentage of reactors was 1 to 11 per cent higher with the larger amount of antigen.

Of the patients tested with each strength dose, 0.43 per cent were reported as showing four plus reaction.

In Kent County, Michigan, 21,781 were tested with tuberculin and/or had x-ray films of their chests in corresponding six month periods in 1950 and 1951. There were 1,757 who were already known by a record of previous examinations to be tuberculin reactors. There were 3,677 tested with 0.01 mgm. old tuberculin and 16,347 with 0.1 mgm. Among the 21,781 who were tested, 1.9 per cent of those in the first decade of life and 7.2 per cent in the second decade reacted to the tuberculin.