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‘Can’t jump to BCG revaccination in India without trial results’

Our testing is inadequate and needs to be scaled up hugely, says Dr Gagandeep Kang

Dr Gagandeep Kang, executive director at Faridabad-based Translational Health Science and Technology Institute, an autonomous body under the Department of Biotechnology, Union ministry of science and technology

Dr Gagandeep Kang is the executive director at Faridabad-based Translational Health Science and Technology Institute, an autonomous body under the Department of Biotechnology, Union ministry of science and technology. Kang is also the vice chair, Coalition for Epidemic Prepardeness (CEPI), a global non-profit enabling vaccine development in the current pandemic. 

Kang, a clinician-scientist is also a key contributor in developing Rotavac, India’s first indigenous vaccine against rotavirus that causes severe diarrhea. Last year, Kang became the first Indian woman to be elected as a fellow of the Royal Society, London.  

Excerpts from an interview on the latest developments in vaccine research on COVID-19, the challenges therein, and the assessment of India’s testing and lockdown measures. 

There are reports of 4,000-odd health workers in hospitals in Australia being administered the Bacillus Calmette-Guerin, or the BCG vaccine, as part of a six-month trial, set to begin soon. What is your assessment of the development?   

BCG is being tried in Australian healthcare workers, and VPM1002, a TB vaccine candidate made by Serum Institute in India, is being tried in Germany. There are other studies planned in the Netherlands and the UK. The idea is to use BCG to enhance immunity. BCG is known to affect the immune system, it has been used in bladder cancers for almost 40 years.  

BCG induces a number of non-specific and specific immune responses that are hypothesised to potentially be useful, but until we have the results of randomized clinical trials, I do not think we can jump straight away to using BCG. But doing a trial with BCG, absolutely-it would be very useful to understand what BCG revaccination can do in our largely already vaccinated population and be a great contribution to global understanding. 

What we are considering about the immune system and COVID-19 is the potential for a phenomenon similar to dengue, where vaccination may lead to more severe disease when vaccinated people are exposed to SARS-CoV2. If this does happen, it would make vaccines a harder target.  

At THSTI, your team is collecting samples from recovered patients. Please explain how and why that's being done, and how that will help in our strategy to fight the disease?  

Samples from recovered patients help in two ways. First, the antibodies made by patients who have recovered can be studied in great detail, and make it possible for us to understand which antibodies protect and which are just a marker that a person has been previously infected. If we can identify which antibodies protect, then any vaccine candidate will have to produce those antibodies to work-better understanding might lead to faster vaccine development.  

Second, the white blood cells from a recovered person can be studied by sequencing to figure out the range of antibodies they make, and it is then possible to clone the most useful antibodies and make them in large quantities. These would then be used for developing new diagnostics tests, or even be considered, if they work, as treatment for patients. 

India's testing strategy has been revised a few days back, but several experts are of the opinion that not enough testing is being done. What are your views on this?  

I agree our testing is inadequate and needs to be scaled up hugely. Conceptually, this is hard for people, policymakers and even many kinds of scientists to understand. There are many causes of respiratory infections, and most people with SARS-CoV2 will recover. We rarely test for influenza, why bother with this? It is because of the rapid spread, and the high vulnerability of certain groups, that we want to test and isolate as quickly as possible to prevent further spread.  

In terms of the individual, having a diagnosis of COVID-19 makes very little difference to the disease process because nothing changes in treatment. But the fact that the infected individual can then isolate themselves has huge meaning for public health. A known positive person who does not spread disease is doing a service for society. 

How will the serological tests that the ICMR is about to start now help in further understanding the spread of the virus?  

Serological tests done on scale in people who do not have symptoms will tell us about what proportion of the population has been exposed. THSTI is working on a test for that. In addition, we are taking other approaches to diagnostics. We are also collaborating with partner institutions and industry to search for appropriate existing drugs, identify new drug candidates and develop vaccines. 

There are different containment/mitigation strategies that are/have been followed across the world. Given the rise in cases that we are seeing in India, do you see us on the right track, and what might need to be done in the coming days? 

Right now, with the lockdown, we have already slowed the spread of the virus, but these gains must be maintained by the actions we take after the lockdown. We have already changed behaviour, I see masks everywhere. If we can maintain handwashing, staying away from others when we are ill, and being extra careful around the elderly and vulnerable, then we will definitely slow the spread of the virus. By how much we do not know, yet. So, we need to work as a society to do that. I hope the government will enable widespread testing and isolation, support not having mass gatherings, work from home where possible, and build up our healthcare systems and our hospitals.