Tuberculin Sensitivity in Town and Country Dwellers

METHOD OF TESTING. For all, except a few who are specially mentioned, this was the Mantoux test. Owing to the impossibility of recalling all the clinic attenders for a second test, the Mantoux test using .01 mgm. of Old Tuberculin (O.T., 0.1 ml. in 1/10,000 dilution) had to be accepted in these. All others were tested with 1 mgm. O.T. (0.1 ml. in 1/100 dilution). Tuberculin jelly (3 per cent. O.T. in a jelly base) was used as a preliminary test early in the series, on those under 10 years at the clinic, and under 12 at the school, but was soon abandoned. For the reasons given below, the entire clinic results of the jelly test were discarded, but as only three of the Fermanagh school boys had the jelly test, the figures for them were retained.