Tuberculosis (TB), a disease caused by Mycobacterium tuberculosis, was found prevalent in society from antiquity. Exact pathological and anatomical descriptions of the disease began to appear in the seventeenth century. In his Opera Medica of 1679 Syluius was the first to identify actual tubercles as a consistent and characteristic change in the lungs and other areas of consumptive patients. In 1720 English physician Benjamin Martin in his publication purposed a new theory of consumption that TB could be caused by a wonderfully minute living creature which could generate lesions and symptoms of the disease. The fight against this deadly disease began in 1882, after the German scientist Robert Koch discovered a staining technique that enabled him to see the causative agent of TB. From then new advances followed in rapid succession.

WHO declared TB a public health emergency in 1993 as it is one of the leading killers among infectious diseases around the world. However, development of new drugs and the Bacille Calmette Guerin (BCG) vaccine lessened the threat of TB. Worldwide a person is newly infected with TB every second and overall nearly 2 billion people have been exposed to TB bacilli. Some of the TB cases are asymptomatic and other may be curable. TB kills between 2 to 3 million people each year, and is the leading cause of death among young adults and a major cause of death among women of child bearing age. The highest rates of TB are found in South East Asia and Africa. In Nepal there are about 40,000 new cases of the disease every year. The Government of Nepal is succeeding in preventing thousands of TB deaths every year due to rapid expansion in access to DOTS. Now 76% of Nepalese have access to DOTS that had been launched from 1996.

TB is easily curable if medicine is taken regularly. Regular consumption of medicine for 6 to 8 months is sufficient to cure the disease. If the prescribed medicines are not taken there are chances of emergence of drug resistant DR TB.

DR TB can be of two types -- multidrug resistant (MDR) and extreme drug resistant (XDR). Incomplete treatment allows provide a suitable environment for the virulent strains to emerge due to mutation. Such stains are not easily treated with the first line drugs Rifampicin and Isoniazid. Such a stage of TB is called MDR TB. For such patients second line drugs Fluropuinolones and Aminoglycosides are administered. These second line drugs are expensive and have more side effects.