Dr Sayera Banu is the head of the Programme for Emerging Infections of the Infectious Diseases Division at the International Centre for Diarrhoeal Disease Research (icddr,b). She has been researching on tuberculosis for the past two and a half decades. On the occasion of World Tuberculosis Day, she talks to Prothom Alo’s Shishir Moral on the work being conducted by icddr,b on tuberculosis, the present state of the National Tuberculosis Control Programme and more.
Of all the topics and diseases in the world, why was tuberculosis in particular that you chose for your research?
Sayera Banu: It was because of my interest in research that I joined icddr,b as soon as I completed my MBBS. Then I later went to Japan where I worked on tuberculosis among other infectious diseases. I got a degree in medical science from Japan. After I returned home from Japan, I got the opportunity for post-graduate training in tuberculosis at the Louis Pasteur Institute in Paris. I earned my PhD degree under Stewart Cole, internationally renowned for deciphering the genome sequence of tuberculosis. At the time, icddr,b was not doing any work on an important matter as tuberculosis.
In short, there are three reasons behind my interest in tuberculosis: The tuberculosis problem is something very big; there was no work being done on tuberculosis at the time; and there was plenty of scope for research. Upon my return from Paris, I created a small TB lab and began working on tuberculosis.
Tuberculosis diagnosis, treatment, everything is provided free of charge to all TB patients. But many people are till unaware that the government provides TB treatment free of cost. I feel people are not very aware of the government’s services. A social movement is needed to fight against a disease like tuberculosis.
How large a problem is tuberculosis in Bangladesh at the moment? Why does it still demand attention?
Sayera Banu: According to the World Health Organisation report, around 379,000 persons contracted tuberculosis in Bangladesh in 2022 and 42,000 died of tuberculosis. Also, 4,900 persons developed multidrug resistant TB (MDR TB). In 2022, a total of 262,731 TB patients were identified, which was 69 per cent of the affected persons. That means 31 per cent remained undiagnosed. Around 3,500 of the MDR TB patients remained undiagnosed. These people are spreading tuberculosis or multidrug resistant tuberculosis.
I have noticed that people are unwilling to test themselves for tuberculosis. It is only when their condition deteriorates seriously that they get tested or seek treatment. GeneXpert machines are used in 50 per cent of the cases to diagnose patients in the country. In the remaining 50 per cent, the conventional microscopes are used. GeneXpert machines must be used in all cases. Children’s TB is not being properly diagnosed in the country. Around 8 to 12 per cent of the diagnosed TB cases should be children, but only 4 per cent are diagnosed. That means even if many children have tuberculosis, it is not being diagnosed, not being treated.
These statistics indicate that the problem is serious. We must be more attentive towards tuberculosis.
If the problem is so large, what were the government and non-government institutions doing all these days?
Sayera Banu: Our country has limited resources. Tuberculosis diagnosis, treatment, everything is provided free of charge to all TB patients. But many people are till unaware that the government provides TB treatment free of cost. I feel people are not very aware of the government’s services. A social movement is needed to fight against a disease like tuberculosis. We do not have that social movement.
What are the government and non-government organisations doing about tuberculosis in the country? What is icddr,b doing?
Sayera Banu: The government is implementing the national programme. This is being supported by BRAC, Damien Foundation and several other NGOs. icddr,b is also providing support to the government. icddr,b has conducted important research on tuberculosis. For example, the contagion on TB in Dhaka Central Jail is 20 times higher. icddr,b conducted work there from 2005 to 2018. Two workers would go there every day and conduct screening. When patients were identified, they were kept separately. At one point, the TB ward at Dhaka Central Jail was extended. A model was created and replicated in the Chattogram, Sylhet and Kashimpur jails. There are TB programmes in all the jails of the country now.
Children cannot easily give cough samples and so it is hard to diagnose children’s TB. Children swallow their phlegm. We have found a way to detect children’s TB by testing their stool. This is a result of our research. Based on our research, the World Health Organisation has decided to change the method of detecting tuberculosis in children and this is being applied in other countries.
Alongside all this, icddr,b has set up ten TB screening centres (TBSTC) in the country, seven in Dhaka city and one each in Sylhet, Rajshahi and Chattogram. People are coming in increasing numbers to these centres for reliable testing. We are doing such work alongside research.
What are the main challenges at present in the fight against TB?
Sayera Banu: We must understand that TB can occur in any part of the body, other than the nails and hair. But some people still thing that TB is only of the lungs. Actually, 25 per cent of tuberculosis is outside of the lungs. It is difficult to motivate people to come for TB screening. Also, it is not being possible to test children in large numbers. We need a much larger number of GeneXpert machines to detect tuberculosis. The patients who have been diagnosed in the private sector, that is, in private hospitals and clinics and at the private chambers of physicians, are not being properly brought under the national programme. Slum dwellers and diabetic patients are at higher risk. But there are shortcomings in properly diagnosing slum dwellers and diabetic patients.
Is it true that there is a spillover, that tuberculosis is spreading from cows to people? Could you clarify this?
Sayera Banu: When germs from animals spread to humans, that is referred to as ‘spillover’. This does occur in the case of tuberculosis. The germ that people are affected by is called mycobacterium tuberculosis. Cows and goats can be affected by this tuberculosis germ too. Mycobacterium bovine can spread from cows and goats to humans. We discovered this in our research. But this is not really a serious problem for Bangladesh.
How serious is the problem of MDR TB? What should be done? What is the government doing?
Sayera Banu: People are affected by multidrug-resistant tuberculosis due to two reasons. Firstly, if the affected person does not take the full course and proper dosage of the prescribed drug, the germs in the body become resistant to the drug. Secondly, multidrug resistant tuberculosis germs can directly enter another person's body. Every year there are 4,900 new case of MDT-TB. Two-thirds of these cases are not diagnosed. Presently over 1,800 MDR-TB patients are undergoing treatment under the government programme. If anyone among them does not undergo proper treatment, they are at risk of XDR TB. It is difficult to save their lives. We do not know how many people with MDR-TB are wandering around among us. The risk is steadily increasing.
If you were made the head of the national tuberculosis control programme or were given all authority regarding tuberculosis, what would your priorities be? What work would you undertake?
Sayera Banu: The implementation of the national programme has been on for many years. There is now need for an overall evaluation. The research that has been successful can be implemented more extensively. This work requires more investment. If I was in charge, I would look for more fund allocation opportunities for tuberculosis.
Secondly, the quality of our service must be improved. Thirdly, a strong drive must be taken up to mobilise public awareness so that people are motivated to take tuberculosis tests.
Saima Wazed is the WHO director for the Southeast Asia region. So there is scope for the experience our country has in tuberculosis research and management to be implemented in other countries of Asia. I would work to that end too.
Do you feel that there is anything that important to be changed?
Sayera Banu: The Cepheid GeneXpert machine is used in our country. This machine has a certain drawback. If there is a low count of TB germs in a body, the result sometimes mistakenly shows that the patient has MDR-TB. We managed to detect this error in our research. This was a serious deviation. It was a serious mistake of the company. Similar research was carried out in India, China, South Africa and Haiti. I contacted the Cepheid company and it has updated the machine as GeneXpert Ultra. Now we can hope for more accurate detection of MDR-TB patients.
Thank you.
Thank you too.
* This interview appeared in the print and online edition of Prothom Alo and has been rewritten for the English edition by Ayesha Kabir