Why TB remains the biggest killer in India

March 24 commemorates the day in 1882 when Dr Robert Koch astounded the scientific community by announcing that he had discovered the cause of TB, the tuberculosis bacillus.

At the time of Koch’s announcement in Berlin, TB was raging through Europe and the Americas, causing the death of one out of every seven persons. Koch’s discovery opened the way towards diagnosing and curing TB. Even after 128 years till this day TB is diagnosed by testing patient’s sputum for TB bacteria. From this it appears that not much research has gone into TB. One wonders whether it has something to do with the disease being of the poor countries.

TB is a major public health problem in India, accounting for one-fifth of the global TB incident cases. Each year nearly 2 million people in India develop TB, of which around 0.87 million are infectious cases. It is estimated that annually around 3,30,000 Indians die due to TB. Currently, TB kills more people in India than any other country (the sub-continent has an estimated 40 per cent of the world’s cases, killing approximately one person every minute).

People with TB often suffer from discrimination and stigma, rejection and social isolation. It is not uncommon for a man to leave his wife if she develops TB, and if she is not already married the stigma attached to TB may prevent a woman from finding a husband. These intangible costs result in depression, anxiety and lower life satisfaction, further adding to the burden of TB.

While many people think TB-related stigma is a thing of the past, studies conducted by the Tuberculosis Research Centre in India show that a significant number of women become homeless after being diagnosed with the disease. Studies by the same organisation have shown that of the number of women who develop tuberculosis, one in thousand lose their home.

The overwhelming problem with the treatment of TB is that cure with DOTS takes 6 months of treatment. DOTS is an acronym for Directly Observed Treatment Short-course, initiated by the government. The great majority of people suffering from TB have amongst the poorest health care facilities in the world. The great majority does not therefore complete their treatment. Premature cessation of treatment will result in relapse and possibly the emergence of drug resistance.

Multi-drug resistant tuberculosis (MDR-TB) can result when TB treatment is incomplete (or in cases where wrong or incomplete combination of drugs is prescribed).

Inadequate treatment
The standard treatment for TB is isoniazid, rifampicin, and pyrazinamide for two months followed by isoniazid and rifampicin for four months. If the treatment is stopped before all the bacteria are killed (because the patient feels better, cannot get to the clinic, or because of a drug shortage) or if an incomplete combination of drugs is given, the resistant bacteria can grow and cause the symptoms to return. Drug resistant forms of the disease take longer to cure, and require more and more expensive drugs to treat. Besides the added time and expense required for treatment and cure rates are low.
In India an alarming 17 per cent patients have developed multi-drug resistance, as per the WHO. The global body in its latest report said that 299 Indians in every 1,00,000 population are infected with TB and the mortality rate is 28 per 1,00,000.

Bacterial cultures grown in the laboratory can tell which drugs kill the bacteria most effectively for that particular strain. If a person has drug resistant TB, anyone they pass it on to will also have the same resistance. The main reasons are improper treatment, intermittent drug shortages and poor monitoring of TB patients under treatment.
It is known that confection with HIV increases the risk of tuberculosis infection developing into disease by a hundred fold. The lifetime risk of about 10 per cent of infection developing into disease in the individual infected with TB alone becomes an annual risk of 10 per cent in the dually infected person.

The association between poverty and TB is well established. Even within the developed world the highest rates of disease are seen in the poorest sections of the community. As the world population increases in some of the poorest areas of the world so the number of people living in poverty has increased. In the last 15 years the number of people living on less than a dollar a day  has increased from three quarters to one and a third billion. More than three-quarters of these are women. The proportion of the world’s wealth owned by the richest 20 per cent has increased from 65 per cent to over 85 per cent in the same time period.
Though we do not have hard data to show that TB increases as poverty increases common sense tells us that it does.