Booster shots have begun to be rolled out in several developed nations around the world as vaccine makers say a third dose of the Covid-19 vaccine is required to keep immunity up, especially in certain sections.

In the United States, the Biden administration has okayed a third shot eight months after the second for everyone. The booster shots come at the cost of several developing and low-income nations who are still struggling to vaccinate their populations with even one dose.

In India, the largest vaccine maker Serum Institute of India’s Adar Poonawalla told ET Now that a third dose is ‘unethical’. Adar Poonawalla’s comments come weeks after his father and SII’s Chairman Cyrus Poonawalla said a third dose of the vaccine is a ‘must’ and should be given six months after the second dose.

“I think what we meant in his comments was that maybe some very vulnerable sections could do with booster shots”, says Adar.

He says there is no evidence so far that a third dose is required and it has not been recommended officially. While vaccine makers like Pfizer and Moderna have pushed for a booster shot saying vaccine efficacy wanes over time, the scientific jury is still out.

In India, top epidemiologist Dr J Muliyil believes that with the widespread of Delta variant in the second wave, even a single shot of the Covid-19 vaccine acts like a booster. Meanwhile, some doctors do believe that those with compromised immunity or people who have undergone organ transplants may require boosters.

The big question though is whether it’s fair to dole out third shots of the Covid -19 vaccine when just a fraction of some countries have access to even a single dose.

“It’s unethical to start giving 3 doses when people in other countries have not even gotten 2 doses”, says Adar.