Belagavi: With a Covid-19 vaccine appearing imminent and with the Centre and some state governments suggesting free doses for the masses, the question being asked is whether those who have recovered from an infection need vaccination. Experts are divided on the issue.
Dr Debprasad Chattopadhyay, virologist and director, ICMR-NITM, said scientifically, those who have recovered from Covid do not need to be vaccinated since they have already developed antibodies to fight the disease.
“In bald terms, vaccinating means administering the virus or parts of the virus to boost immunity,” he said. “Those who have recovered are already immune. Scientifically speaking, vaccination is not necessary for them.”
However, Dr Ramesh, an epidemiologist, said since there have been examples of reinfection, a vaccine is a must for all, while Dr Giridhara Babu, epidemiologist and member of the state advisory committee, said it is premature to talk about the issue now.
“Although there is no evidence to suggest that the virus has mutated in India, there isn’t sufficient data on how long antibodies remain in the body of recovered patients,” Dr Babu said. “There are two extreme examples before the scientific community. For example if a person has recovered from chickenpox, then administering a vaccine is unnecessary, but for flu, people have to take booster shots regularly. The novel coronavirus could go in any direction or stay between these two extremes. The dosage of the vaccine has also not been decided yet.”
Dr Srinivas Kakkilaya, general physician who has also co-authored a book on Covid-19, differed with Babu. Kakkilaya said for the first time in history, the scientific community knows so much about a new virus in such a short span. “A study on the response of memory T cells to the virus showed a robust response from the T cells. This means even though antibodies do not last long, the T cell will help generate antibodies to stop the virus from binding to the cell.”
He said there is “absolutely no necessity” to vaccinate people who have recovered and the government will “save a lot”. “Many would not need the vaccine at all,” he said. “We may not know how long antibodies remain in the body, but we also do not know how long immunity provided by a vaccine would last. T cells then come into play.”
However, Amith S Bhate, director, Jeevan Rekha hospital, which is conducting human clinical trials of several vaccines, was of the opposite view, saying those who have recovered from Covid-19 would also need to be vaccinated. On the dosage, he said in the first and second phases of Covaxin trials, two shots were administered. If the same dosage continues for the third phase, then everyone above the age of 18 would require two doses when the vaccine enters public domain.