TB is the leading cause of death from infectious disease in developing countries, and kills 3 million people a year worldwide.

In Western Europe and other industrialized countries where TB has become a rare disease, the declining incidence has been halted or reversed.

Between 1985 – 1991, an 18% increase in TB incidence was reported in the USA, and a doubled incidence of TB in New York city.

Contributing factors are:

a. influx of immigrants from countries with endemic TB,

b. increased number of social outcasts living in crowded places,

c. AIDS-epidemic,

d. emergence of MDR-TB (19% of new TB cases in New York in 1991), and

e. dismantling of TB control programs.