Serum Institute of India chairman Cyrus Poonawalla on Friday said that since the antibodies go down after six months, people should take a third or ‘booster shot’ of Covishield, the coronavirus vaccine manufactured by his firm. He also mentioned that he was not in favour of mixing two difference vaccines and criticised the union government for banning exports of vaccines.

“After six months, the antibodies go down and that is why I have taken the third dose. We have given the third dose to our seven to eight thousand SII employees. For those who have completed the second dose, it is my request to take a booster dose (third dose) after six months,” he said.

The ideal gap between two doses of Covishield is two months though the Union government increased it to three months because of dose shortage, he said.

“I am against the mixing of two different vaccines. There is no need to mix two different vaccines,” Poonawalla said.

This comes after a recent ICMR study suggested that a cocktail of Covishield and Covaxin was found to have generated better immunity within a small group.

If such a combination of doses did not work, each vaccine manufacturer will blame the other company, he said.

However, he clarified that such mixing can be resorted to if a particular vaccine is not available at the time of the second dose.

Asked for his view on the government’s assurance to complete the vaccination in the entire country by the end of this year and the claim that 45 crore doses will be available by September, he said, “What do you think ? Politicians sometimes boast…

“Our production of COVID-19 vaccine is 10 crore per month and producing that much quantity is not easy,” Poonawalla added.

No company in the world can provide 10 to 12 crore doses in a month, he said.

“However, with the advance preparations by SII and investments of thousands of crores, we can produce 110 to 120 crore doses per year. As other companies are also producing the vaccines, the immunization will increase,” he said.

Poonawalla termed the Union government’s decision to ban the export of vaccines as a “very bad move”.

“My son asked me not to open my mouth (on the issue). But it is my view that exports ought to be opened,” he said.

Over 150 countries are dependent on the SII for vaccines and are blaming the company for stopping the supply during a crucial period, he said.