The use of a drug-combination for which the mycobacteria are well sensitive continued for sufficient time ensures that the role of chemotherapy is met with: ensure a permanent cure without development of drug resistance.

Chemotherapy has proven very effective in making TB a rare disease in Western Europe and industrialized countries, but unsuccessful in eliminating TB.

The causes responsible are legion:

*improper use of antibiotics leads to drug resistance,

*HIV infection facilitates transmission of TB,

*decreased priority of disease control increases the possibility of an outbreak.