Third Covid wave may not be severe but prepare for worst: INSACOG's Arora

India may not see a terrible third wave, but it has to prepare for the worst, Narendra Kumar Arora, co-chairman of the Indian Sars-Cov-2 Genomics Consortium — (INSACOG), told Business Standard. Amid concerns around booster shots and fears of a third wave, Arora said decision on such a dose would be taken depending on the local context. 

“That the US and Israel are giving these shots is noted but our decision will be based on our data. We have suffered Delta already. And Delta has attacked them now,” Arora said. 

He said the booster dose was dependent on epidemiology of the circulating virus and the intensity of infection. It’s also dependent on the durability of protection in the context in which the vaccine is given. 

INSACOG is setting up a national vaccine tracker which will make available data on breakthrough infections. “It will be launched soon,” Arora said. 

The Delta variant, which hit India in the second wave, has been responsible for a lot of breakthrough infections. Whether we are seeing an increase in breakthrough infections in a particular population is also an important factor in booster dose consideration, according to Arora. 

While stressing that decisions related to vaccine would be taken on a scientific basis, Arora said published studies of breakthrough infections among health personnel (who were the first to be vaccinated) indicated that such infections were not of concern.

A study on vaccine efficacy conducted by PGI Chandigarh showed that two doses of Covid vaccine gave 98 per cent protection against the disease. One dose gave 92 per cent protection, according to the study done on Punjab police personnel. 

Another study by Christian Medical College, Vellore, found that the risk of infection among the fully vaccinated health care workers was significantly lower than those unvaccinated. 

Amid widening gap between the vaccination coverage in wealthy and poorer countries, the World Health Organisation had said boosters should be on hold until end of September to ensure at least 10 per cent of the population of every country was vaccinated.

India has so far fully vaccinated around 10 per cent of the total adult population. Less than 24 per cent have received a single dose so far, according to Our World in Data. 

INSACOG is keeping a close watch on the gap of 12 to 16 weeks between the two doses of Covishield. “There is adequate evidence that increase in the gap between the two Covishield doses gives sufficient protection. These things are constantly under watch,” Arora said. 

There are two types of immunity which the vaccines are providing — visible antibodies and invisible based on memory cell response, Arora pointed out. He said people should not rely on antibody tests to find if they have got protection from the vaccine. The B cell and T cell response — which refers to long term immunity through the memory cells in the body — is measured only in three labs in the country. This test is only available for scientific research purposes. Arora said it had been found that the Covid vaccines in use produced such long term immunity in people.