The head of India’s premier virus research institute said on Thursday the Covid precautionary doses were increasing the antibody levels in recipients and it was up to the Centre to decide whether one has to keep taking booster doses at regular intervals.
Priya Abraham, director of the National Institute of Virology, Pune, said studies had shown that antibodies start declining four to six months after taking Covid vaccines. The booster or precautionary dose, she said, increases the antibody levels.
Abraham pointed out that antibodies start declining around that time even in people who had Covid.
The number of people taking booster doses in Bengal had been low for many weeks and started picking up only after a fresh surge in Covid cases started. On Thursday, the state reported 3,029 new Covid cases.
An official in the West Bengal government’s health department had told The Telegraph recently that till a few weeks ago around 20,000 people were taking the booster dose across the state daily.
It went up to 50,000 and then 80,000 recently. On Thursday, 1,23,098 Covid shots were administered in the state.
“We looked at individuals who took two doses, which is what is known as primary vaccination. We looked at their antibody titer (level). This was six months after receiving the two doses. We checked the protection against the different variants of the virus — Wuhan, alpha, beta and omicron. When we gave the booster doses, the antibody titer went up in those individuals,” Abraham said on the sidelines of a lecture she delivered at Science City to school students.
The lecture was titled “From Virus Discovery to the Vaccine — A Story from ICMR (Indian Council for Medical Research) — National Institute of Virology”.
Abraham showed slides with results of studies comparing antibody levels in people who took booster doses and those who only had the primary vaccination.
“Taking the third or booster dose can actually increase antibodies in an individual,” she said.
People could still get infected with Covid after taking the booster shot, she said, but the risk of severe disease would be less.
“We have protection against serious disease, hospitalisation and death but not necessarily against infection. That is why we are still urging people to take the booster because they will be protected against serious outcomes of the disease,” she said.
When asked about the Centre’s decision to reduce the gap between the second dose of Covid vaccines and the booster dose from nine to to six months, Abraham said: “Six months seems to be a good time to boost immunity again because antibodies start declining from between four and six months.”
“Antibodies start declining from between four and six months even in those who get infected with Covid.” she said.
The Centre on Wednesday announced that all adults would be offered free booster doses of Covid vaccines at all government vaccination clinics for 75 days from Friday (July 15).
Abraham said it was up to the Centre to decide whether one should keep taking Covid booster shots at regular intervals. “There is no guidance yet in our country whether future boosters are required. Antibodies start declining after four to six months, studies will tell. The government of India takes decisions based on studies. There is no guidance yet on whether to take a fourth or a fifth booster dose.”