‘Nutrition almost acts like a TB vaccine’
What have you gathered in your early days as Principal Adviser to the National Tuberculosis Elimination Programme?
I have taken stock of the Programme. I’ve also had the opportunity to brief the minister about my observations and suggestions and take his advice on the way forward. It has been a very fulfilling experience because I have spent my life on TB research.
How achievable is India’s target of TB elimination by 2025 given our 25 per cent share in the global burden?
As per the World Health Organisation’s definition of TB elimination, the global target actually is to achieve it by 2030. In India, Prime Minister Narendra Modi said we are going to achieve it by 2025. That was a huge boost for the global TB programme. I think it was very good to have set that ambitious goal.
However, if you really look at the burden of TB and the tools we have today — we don’t have a very good vaccine, we only now are scaling up rapid molecular diagnostics, treatments are long, socio-economic issues impact outcomes. Keeping these things in mind, it won’t be surprising if we don’t achieve the elimination goal by 2025. However, what this has done is, it has re-energised the programme, brought more resources, more innovations.
There has been, compared to where we were in 2015, a reduction both in TB deaths and a small reduction in the incidence or burden. There are variations between states. But overall, we still have a very high burden of TB. And it’s going to take some more time for us to really bring that down.
In two-three years, we’ll have good results coming on the tuberculosis vaccine… nutrition trial done in Jharkhand showed that if you give good nutrition to household contacts of patients, you can bring down the incidence of TB by over 50 per cent.
—Soumya Swaminathan, principal adviser to the National Tuberculosis Elimination Programme
Will we be there by 2030?
It will depend on data, on what combination of strategies we use, how quickly a vaccine is developed and deployed. The exact time period needs to be worked out. By 2030, we can have a very significant decline in the burden. But I can’t tell the exact date by which we’ll achieve the WHO goals.
Where have ICMR’s efforts with the TB vaccine reached?
The TB vaccine trial was started when I was Director General of the Indian Council of Medical Research (ICMR). I had set up The India TB Research Consortium to bring departments, ministries and groups together to get additional funding. Many good things have come out. One is the vaccine trial where there were two vaccines being tried. A recombinant BCG vaccine is made by the Serum Institute of India. The other is the MW vaccine made by Cadilla for leprosy and there is some indication that it might also be effective against TB. So, those were the two vaccines and there was also a placebo arm.
This trial has enrolled over 12,000 household contacts of TB patients. The results were very recently un-blinded. And essentially, what it shows is that overall, there’s not much of a difference between the arms. But in younger individuals under the age of 18, the recombinant BCG vaccine has some moderate efficacy in the range of 30 per cent. This is preliminary data but it is promising because it gives some hope that even if it’s not in all people, at least in a subgroup, maybe in the younger age group, a re-vaccination strategy might be helpful.
The ICMR and Ministry of Health experts are going to be discussing on this to decide what should be the next step in terms of looking at using a re-vaccination approach.
The other thing which came out, which has been globally recognised, is the nutrition trial done in Jharkhand called the Rations Trial, funded by the same research consortium. It showed that if you give good nutrition, calories and protein to the household contacts of TB patients, you can bring down the incidence of TB quite significantly by over 50 per cent. For the first time in the world, any trial has shown that nutrition almost acts like a vaccine. In fact, it’s better than the existing BCG vaccine because the reduction in TB is around 48.49 per cent. That is very encouraging. Considering we don’t have a very good vaccine today, nutrition could actually be the approach in places like India and other countries where malnutrition is a risk factor for TB.
TB is preventable, curable. People are hesitant to report symptoms. We still see discrimination. We must get
rid of the social stigma. It’s like any other infectious disease. —Soumya Swaminathan
Why has India struggled to control TB?
In India, around 40 per cent of the cases are due to underlying malnutrition. TB is a bacterium that is present quite widely. All of us are exposed to it. We inhale it, but most of us have a good immunity and are able to contain it. But if your immunity is down for some reason — malnutrition, diabetes, immunosuppressive drugs, HIV — you get active TB disease. These are the risk factors. Smoking and alcohol are also risk factors. In India, we have a combination of all these and are at high risk. That is one reason.
The other is that we are still mainly using smear microscopy for diagnosis and therefore we are missing a lot of cases because it’s a very insensitive tool. You still have a lot of people out in the community who are spreading TB undiagnosed.
The third thing which the TB prevalence survey (2019-2021) showed is that there is something called subclinical TB, where the person doesn’t show much of symptoms and so they don’t even go for treatment. It is difficult to diagnose unless you do an X-ray. Because of such cases, it becomes very difficult to eliminate TB.
What’s the burden of undiagnosed TB?
We are missing almost 60 per cent of cases.
Your suggestions on diagnostics?
We need to provide 100 per cent molecular testing for every individual who comes with symptoms. Right now, we are at 30 per cent. That is going to find people, put them on treatment, reduce death, and ultimately reduce the prevalence. We also need to start using X-rays more. We have seen cases missed by sensitive molecular tests being picked up by simple test X-rays. Nowadays, you have these handheld X-ray machines. You can go to a village, conduct a health camp, do X-rays and identify those who have a lesion, immediately take sputum, do the molecular test, identify and start treatment. That’s the kind of thing we need to start doing much more. The Programme is already purchasing these machines. And you use artificial intelligence to read the X-rays. You don’t even need a radiologist.
That’s a new thing?
That is new. There are several companies that have got AI algorithms, which have been validated and approved by ICMR.
What are we doing in diagnostics?
Smear microscopy, where we are missing cases because smear becomes positive only when you have millions of bacteria. Everybody doesn’t have that. When you take out sputum, you may have a few bacteria that can be picked up only by molecular tests.
We said in 2018 that we will eliminate TB by 2025. What have we achieved so far?
The TB programme in terms of logistics and supply chains has traditionally been good. But in the last one-and-a-half, two years, there have been some challenges with stock outs, both of diagnostics and drugs. That has led to some setbacks.
What’s the cause?
Procurement procedures are quite complex in government. Somewhere there was a block and things got delayed. Now it has been corrected. Going forward, we should not see any kind of shortages. We have made projections now for the next couple of years. But there’s a need to improve our logistics and supply chain management, not just at the central level where drugs are procured but down the line when drugs go to states, then districts, then PHCs. One thing the government must invest in is that every state must have this medical supplies corporation, not just for TB, but for all essential drugs that are used. Right now, maybe 10 or 15 states have it.
By when can we expect the TB vaccine deployment?
Some further discussions need to be held on the recombinant BCG vaccine based on the preliminary results from the trial. We also need to look at cost-effectiveness, feasibility, acceptability. All those analyses will be done by groups of experts. Maybe in two-three months, we’ll have some clear direction.
Meanwhile, there are other vaccine trials going on. One is called MTB vac, for which Bharat Biotech has signed an agreement with Biopharma. They are going to manufacture. Phase 3 trials will also be done in India with ICMR. And there is N72, a GSK vaccine the Gates Foundation has taken. That is not happening in India, but across Africa and Southeast Asia. So, in two-three years, we’ll have some good results coming.
Can the nutrition trials offer a solution?
Exactly. That’s another area where the government and the ministry are really looking in-depth on how to implement and take forward those results. Because, as you know, nutrition is not generally part of the health ministry’s efforts. It comes under other ministries and departments. What we are going to do is we’re going to start by providing nutrition to all TB patients whose BMI is less than 18.5, who are malnourished. That is easier to do because these people are already under treatment. They are coming to you so you can give them nutrition, high protein, high-calorie supplements. For the families, I think the logistics are more difficult. That will be worked out. For TB patients, this can start very soon.
How do you see the new four-drug treatment regimen for multi-drug resistant TB patients?
Right now, procurement is going on. Once it is introduced, it will be available for patients normally, where they go for TB treatment — what is called the District Drug Resistant TB centres. It will cut down the treatment duration from 20 to six months. All studies have shown it lowers the death rate compared to standard MDR TB regimens. You get more than 90-91 per cent cure, whereas today, with existing regimens, you get 70-72 per cent. It lowers the mortality rate from 14 per cent to about 4.
Who is the most vulnerable to TB?
Firstly children under two because they have lower immunity and if they are exposed to TB in their household, they have a high chance of getting severe forms of TB, like meningitis. Then the adolescent age group around puberty. And then the middle age, 35 to 55 year group, especially men. Finally, the elderly above 65, men and women. Actually, everybody is susceptible all the time. If your immunity drops, you become super susceptible at any age.
So it’s not just a poor person’s disease?
No, it’s airborne and can affect anybody. The difference is if you’re poor, you have other risk factors like poor housing, exposure to smoke, pollution, malnutrition. That is why you do see more TB among the poor.
There’s a perception that TB is infectious.
Once a person is under treatment, within two weeks, they are almost non-infectious. And you can always take precautions. You and family members should wear a mask.
