Revisit TB programme before it is too late

Tuberculosis (TB) is a major public health problem in India and in many other developing countries. By the time you finish reading this article, assuming that it would take around 10 minutes or so, six people in India would have succumbed to the disease.

According to Government of India figures, every year 20.2 lakh people develop TB and an estimated 2.2 lakh die from the disease. According several authorities, these figures are an underestimate and the real figures could be even scarier.

It is in this context that the World Health Organisation (WHO) has aptly launched a campaign observing March 24 every year as World Tuberculosis Day, with a focus on any one aspect of TB and this year the focus was on “Unite to End TB.” It also commemorates the day in 1882 when Dr Robert Koch astounded the scientific community by announcing that he had discovered the cause of tuberculosis, the TB 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 people. Koch’s discovery opened the way towards diagnosing and curing TB. Subsequently, in 1890, Koch described tuberculin reaction — a tool to detect TB. But it failed as it was highly contaminated.

It was Charles Mantoux, a French scientist, who, in 1907, along with others, evolved and developed the tuberculin test. The test included a simple procedure to detect TB and this was extensively used as a powerful tool to detect and control the disease, especially in the US. Astonishingly, this was how TB was controlled and has almost been vanquished from most developed countries like the US and the western European countries.

They tackled the problem by not only screening humans, but also examining the cattle with the tuberculin test. The objective of examining the cattle was two-fold. First, to prevent transmission of TB from animals to humans. The bacteria that causes TB in animals is called Mycobacterium bovis (M bovis). Secondly, it also improved the quality of animal products like meat and milk. This in turn played huge dividends as the products showed improved markets, thus increasing the national export and preventing the spread of TB from animals to humans.

For example, Bovine TB in England costs taxpayers over £100 million a year. It causes devastation and distress for rural communities. Controlling TB required culling of 28,000 cattle in 2015. But by doing all this, England gained the “Officially TB Free (OTF)” certificate from the European Union. The certificate will help boost its trade opportunities. This also means that in future, some herds will require less regular testing, reducing costs for farmers. This is the first time England has enjoyed this status, making beef export from the country more attractive for trade partners around the world.

The German story is different, in that, it achieved the OTF status much early. In Germany, bovine tuberculosis is a notifiable animal disease. Due to intensive disease control programmes that were initiated in West Germany in the 1950s, and in East Germany in the late 1970s, it is considered practically eradicated today.

From July 1, 1996, Germany was officially declared free from bovine tuberculosis pursuant to EU decision. To maintain this status, at least 99.9% of cattle holdings had to be officially free from tuberculosis every year. Based on this disease-free status, the nationwide routine tuberculin testing of cattle was stopped.

In accordance with these regulations, control is mainly based on official meat inspection and post-mortem examination of dead animals by veterinary service laboratories and tuberculin testing in some areas.

The TB transmission from cattle to humans was once common in the US. This has been greatly reduced through decades of disease control in cattle. The US Department of Agriculture, state animal health agencies and livestock producers have nearly eliminated M bovis infection from cattle there.

However, M bovis can be found in wild animals such as bison, elk and deer, and uninfected cattle that come into contact with these wild animals can become infected. Cattle outside the US, particularly in developing countries, might not have the same level of inspection for M bovis infection.

Wrong focus

It is the sum total of all these experiences from various countries that should have formed the backbone of the TB programme in India. Instead, its strategy has been too focussed by providing early detection and anti-TB drug treatment. The TB programme does not recognise that the disease can be spread from cattle to humans. For instance, a farmer in a rural area has close association with the cattle — the cattleshed is either part of his house or situated next to it, thus exposing the entire family.

With the surge of diabetes in rural areas, people have become more vulnerable to TB too, as diabetics have low immunity. This apart, the huge number of malnourished children who lack immunity are highly susceptible to TB. As a consequence of these and several other factors like poor housing, HIV/AIDS, alcoholism and tobacco abuse, the problem of TB has further catapulted.

The worst scenario is the emergence of drug-resistant TB. By using the Right to Information Act, it has been learnt that the percentage of drug-resistant TB is much higher than the 2 to 3% cases that are reported to the WHO. As per the data gathered from 18 sites around India, 6.7% of TB patients tested were drug-resistant. And in one clinic in Mumbai, about 28% of TB patients tested earlier this year were drug-resistant. This calls for urgent relook at the TB programme for India, or else it can become an unending problem.

(The writer is President, Drug Action Forum – Karnataka)