Childhood tuberculosis in Alabama: epidemiology of disease and indicators of program effectiveness, 1983 to 1993

An 11-year review of childhood tuberculosis in Alabama was made in order to define indicators of program effectiveness in interrupting community transmission. Minority (nonwhite) children, 96% of whom were black, had the highest risk of disease (odds ratio, 5.5; 95% confidence interval, 3.9, 7.7). Of 171 cases, 71% (n = 122) occurred in blacks and 2% (n = 3) occurred in Asian-Pacific islanders. Age 0 to 4 years (107 of 171) compared with age 5 to 14 years (64 of 171) was an additional risk factor for the development of tuberculosis (odds ratio, 3.4; 95% confidence interval 2.5, 4.7)), whereas gender was not. Males accounted for 49% of cases (83 of 171). During the period 1983 to 1993 there was no trend of increasing or decreasing numbers among child cases (trend test P = 0.94) despite significant changes by year. The purified protein derivative test had a 9% (8 of 89) false negative rate and was significantly more likely to be negative in children younger than 1 year (4 of 12 vs. 4 of 77; P = 0.01). During the 2-year interval 1992 to 1993, 19% of cases were thought to be preventable. We believe that the PPD skin test is useful and an improved contact investigation is essential to preventing childhood tuberculosis. Miniepidemics of transmission of tuberculosis from adults to a large group of children partially explain the observed disease pattern.