Tuberculosis Transmission in the 1990s

Abstract

Two studies reported in this issue of the Journal^1,2 use new techniques of molecular epidemiology to extend our understanding of the transmission and control of an ancient disease -- tuberculosis. The conventional wisdom has been that 90 percent of active cases arose from foci of infection first acquired years or decades ago. In the United States alone, the pool of persons with latent tuberculous infection is estimated at 10 to 15 million³. But where do today's active cases come from? The reports in this issue suggest that at least in San Francisco and New York City, a third . . .