According the National Tuberculosis and Leprosy Control Programme (NTLCP) (2002) there has been an estimated population of about 1.7 billion people who are infected with tuberculosis and each year eight to 10 million new cases are thought to occur leading to 2.9 million deaths annually. This constitutes about 7 percent of all deaths from any cause worldwide and 26 percent of all potentially preventable deaths. About 95 percent of new cases and 99 percent of tuberculosis fatalities occurs in developing countries where the greatest incidence and mortality concentrate in the most productive age group from 15 to 59 years making the disease economically extremely important.
A country can be divided in terms of the current level and past trends of the annual rate of infections and health resources availability into four groups.
- In industrialized countries tuberculosis has been declining very rapidly as transmission has been diminished. The downward trend started in 19th century with solid economic development, but after the Second World War the decline increased drastically, coinciding with the introduction of anti-tuberculosis chemotherapy. At the moment the favourable trend has changed in some of these countries (USA and Japan).
- In some middle – income developing countries in Latin American, West Asia and North Africa, tuberculosis is losing its status as a major health problem.
- In other middle- income countries in East and South-East Asia the decline of Tuberculosis is slow and the disease remains very important.
- In the majority of low-income countries in sub-Saharan Africa. At the moment less than 5 percent of tuberculosis cases in the world are associated with HIV infection, but these cases are concentrated in ten African countries, where the AIDS epidemic is running tuberculosis control programme. The highest incidence of tuberculosis in 1990 was in sub-Saharan Africa (229/100,000) followed by Asia, North Africa and Latin America. Industrialized countries the incidence varies between 10/100,000 and 40/100,000.
Reference
National Tuberculosis and Leprosy Control Programme (2002). Revised Worker’s Manual. Luton: Crest Books.
