Dr Raman Gangakhedkar, former head of epidemiology and communicable diseases at the Indian Council of Medical Research, has discounted the need for the fourth dose of COVID-19 vaccine given the current evidence about the coronavirus and its variants.If a person has taken a third dose of the anti-COVID-19 vaccine, it means his T-cell immune response has been trained thrice, Dr Gangakhedkar said on the sidelines of a function on Tuesday.”The core virus (of COVID-19) has not been changed so much that a new vaccine would be needed, so try and have trust in our T-cell immune response,” he said.”Looking at the current evidence (of variants of the virus), it is not that big that there is any need for the fourth dose of the COVID-19 vaccine. There are many reasons for that. Currently, whatever vaccines are there, the virus makes the escape mutants over them which causes infections,” he said.According to Dr Gangakhedkar, old people and those suffering from chronic morbidities should continue to take precautions such as wearing of masks.”For the fourth dose, I think, there is still time to think, because if any new variant comes, it would not be from the SARS-COV2 family. It could be a completely new variant and when it comes, we will think about it as our genomic surveillance is still going on. No need to get worried now,” he said.Dr Gangakhedkar appealed to follow two things, including taking a precautionary dose and taking all the precautions for those who are in a vulnerable group.He was speaking on the sidelines of a discussion on the book ‘Braving a Viral Storm: India’s COVID-19 Vaccine Story, organised by the Pune International Center.