A Tuberculin Survey in a Metropolitan District and its Relation to Morbidity and Mortality

Abstract

A tuberculin testing survey was made in 1949 and 1950 of all admissions to a New York City chest clinic. Tests were administered to 5,209 persons. The tuberculin reactor rate increased steadily in this community to a maximum at 45 years of age. There was no apparent difference in the male and female rates. The rates among non-whites were consistently higher than among whites. There was a falling off in the tuberculin reactor rate in the older age group possibly due to decrease of skin sensitivity. However, the test is useful because of large case and death rates occurring in this age group in those with positive reactions. The tuberculin reaction rate among non-contacts is lower than that among contacts in childhood and adolescence; but by adult life there is no apparent difference in contact and non-contact rate. This is believed due to the general tuberculinization of the population by contact with known and unknown cases of this disease. In this community, more new cases of tuberculosis occur in female than in male children, and rates for both sexes rise abruptly in adolescence. The maximum female case rate occurs from 15 to 29, but the male rate continues to rise through middle life and old age until the rate of new cases is more than three times that of females. This is true both in the general population and in those infected as shown by positive tuberculin tests. Though non-whites comprise only 6.4 per cent of the population, they contribute 22.5 per cent of new cases. Deaths are few from tuberculosis in children and adolescents in this community. The maximum female death rate is reached from 30 to 45 years. The male death rate rises continuously from birth to old age, and from 45 through 64 is four times the rate among females. The large excess of the male death rate over that of females is found both in the general and infected population. In this community, prevention of clinical disease and death from tuberculosis should be concentrated on the older male. However, there is a large potential reservoir of tuberculous infection from adolescence onward as shown by the tuberculin reactor rate. Only when this rate falls to a low level would one consider that the tuberculosis problem was on the way to solution. The chief seed bed for this high tuberculin reactor rate is probably in the known and unknown older males with tuberculosis who constitute a large reservoir of cases and are the source of the high death rate. Special emphasis should be given to the non-white population who contribute a marked excess of known new cases and of deaths over their ratio in the general population. The high tuberculin rate found in Jamaica, N. Y., suggests that there may be a reservoir of unknown tuberculous cases causing a general tuberculinization of non-contacts in the population by adult life, though in the absence of a longitudinal study, the high rates in adult groups may reflect the more general infection earlier in this century.