[Risk factors in infection and development of tuberculosis in students]

A study was carried out in 266 571 students, examined during the 1952--1974 interval, on a series of risk factors of infection and morbidity from tuberculosis with regard to certain epidemiological, immunobiologic and peristasis parameters. In the interval studied, morbidity from tuberculosis fell sharply from 923 per 100,000 in 1952 to 83 per 100,000 in 1974. The highest proportion of infection occured in the first three years at the university, particularly among meidcal students. The risk of infection of alergic subjects with an intradermoreaction greater than 15 mm in diameter, was approximately twice that the hypo- or normoergic subjects and the proportion of vaccinates who contracted the disease three times smaller than that of the non-vaccinated subjects.