Risk of Persons in Familial Contact with Pulmonary Tuberculosis

Data so far accumulated from a survey of the negro population of Kingsport, Tennessee, afforded material for preliminary study of the suitability of retrospective records. Mortality from all causes, in this group, is compared with current mortality in the negro population of the State as a whole by reducing mortality in the Kingsport families to age-specific annual death rates. Comparisons indicate that familial records are not grossly erroneous. Mortality and morbidity rates of "contacts" and of persons with no history of known household contact with tuberculosis are computed. Though the numbers on which age-specific rates were calculated are very small, comparisons indicated that persons with a positive history of household contact had, thereafter, tuberculosis morbidity and mortality rates about double those of the control population, and also had a higher mortality from other causes. This agrees with Weinberg''s observations. The method of treating these data, similar to that used by Elderton, Perry and Weinberg, is detailed, to illustrate a technique for study of material too often remaining unassembled.