BENGALURU: Even after administering more than one billion Covid-19 jabs, India unfortunately doesn’t have data to take a concrete decision on booster vaccine doses, say experts. While countries like US, Malaysia and UK, after witnessing a resurgence in cases, have already started giving booster shots, experts feel that even after half the country is either vaccinated or infected, the authorities have not bothered to compile data, which is important to take a call on booster doses.
“It is unfortunate that a country like Israel, with a population less than Tamil Nadu, is deciding the vaccination policies for the rest of the world. Given the fact that unlike in other parts of the world, half the population in our country is either infected or vaccinated. So would it be so difficult to get our own data?” asks Dr Gagandeep Kang, microbiologist and virologist, and professor at Christian Medical College, Vellore.
A study published in The Lancet on October 29 concluded that Covid-19 vaccine effectiveness evaluated at least seven days after taking the booster dose, compared with only two doses at least five months ago, was estimated to be 93 per cent against admission to hospital, 92 per cent against severe disease, and 81 per cent against Covid-related deaths. While many countries have started giving the third jab, experts say this exercise cannot be carried out in India.
“India lacks data on waning of immunity, hospitalisations and deaths, despite taking the vaccine as well as mixing and matching different vaccines. We are not ready for a booster dose, from a public health and scientific literature viewpoint,” said Dr Ravindra Mehta, Senior Consultant and HoD, Pulmonology and Interventional Pulmonology, Apollo Speciality Hospital.
Experts and researchers say at some point, people will have to go for a booster dose. “But how do we know when we need them? Is it now? Or two years hence? Who should take it? We need literature,” said Kang. With literature available in India that vaccines have not worked in immuno-compromised individuals, Dr Kang questions, “When two doses of the same have not worked on such people, should we not look at whether vaccination of a different platform needs to be given?”
Dr T Jacob John, leading virologist at Christian Medical College, Vellore, says scientifically, there is no doubt we will need a booster dose. “It is unethical to not vaccinate the elderly, those with comorbidities, chronic diseases etc with a booster. It is needed to save their lives. Also, it is proven that a booster helps slow down the virus’s transmissibility. Then why are we not taking the decision yet?” he said.
However, Dr Mehta argues that once a significant portion of the Indian population has received the second dose, and there is sufficient data on Covishield and Covaxin, we can decide on who will require the booster dose and the combination of vaccines. However, mRNA vaccines are still not available in India, he pointed out.
“In Israel and US, the talk of booster doses came about as the two doses of vaccination reduced hospitalisation and death, but were less effective in preventing infection. Hence, they considered giving booster doses to the elderly, immuno-compromised etc,” Dr Mehta added.
Experts recommend that those who had taken two doses of a vectored vaccine, can take a third inactivated virus vaccine. For those who took two doses of inactivated virus vaccine, the third can either be the same inactivated vaccine or a vectored one.