Tuberculosis is the single communicable disease responsible for the maximum number of deaths around the world. The official claim, thought to be conservative, is that there is a pool of 300,000 infected people in Mumbai. About 50% of the population of the city suffers from respiratory problems and are at risk of infection. The epidemiology of the newly evolved multi-drug resistant strain for Mumbai is not available.
In 1882 Robert Koch isolated Mycobacterium Tuberculosis as the causative agent of the disease. The disease is air-borne; bacteria disperse in the atmosphere in tiny droplets of fluids from infected persons, and can survive outside the human body for long periods. Sunlight is effective in killing the bacterium. Wide differences in virulence between different strains of the pathogen suggests a long co-evolution between humans and the disease.
Statistical surveys in many parts of the world over many years of this century strongly indicate that social aspects are important in controlling the spread of Tuberculosis. Between 1955 and 1958 a large scale National Sample Survey was carried out all over India to document the epidemiology. It was found that urban and rural populations were equally at risk. About a quarter of the infected people found in the survey had a history of other members of the households also infected.
These associations were recognised by the Bhore Committee (1946) and the Mudaliar Committee (1961), and were incorporated into the National Tuberculosis Program, formulated in 1962. The program was evaluated in two studies, in 1975 and 1988. It was found that less than 20% of the infected people got complete treatment from the public health services.
Multi-drug resistant TB (MDR-TB) arises from such inadequate and incomplete chemotherapy. Its treatment is chancy and expensive. A major health problem may arise in the near future, since increased incidence is seen among the urban poor, specially among migrants, the homeless, drug-addicts and indigenous people, and because of co-infection with AIDS/HIV.
A revised national program has been undertaken, with a $150 million loan from the World Bank. This is contingent on the adoption of a WHO prescription package. This includes the condition that health workers have to watch their patients swallowing their pills thrice a week for two months out of the six month treatment program.