The Union Ministry of Health and Family Welfare on Tuesday clarified that it never spoke about vaccinating the entire population against the coronavirus.

Health Secretary Rajesh Bhushan made the clarification at a press briefing on the coronavirus situation in the country. “I just want to make it clear that the government has never spoken about vaccinating the entire country,” he said. “We should discuss these scientific issues based only on factual information.”

Indian Council of Medical Research Director General Balram Bhargava, on the other hand, said that it may not be necessary to vaccinate everyone in the country.

“Our purpose is to break the chain of viral transmission,” Bhargava said. “So if we are able to vaccinate a critical mass of people and break that virus transmission, then we may not have to vaccinate the entire population.”

The ICMR chief also said that the efficacy of the vaccine was an important factor to consider. “There is a range,” he said. “For someone it may be 60% effective, for someone else it may be 70% effective. So efficacy is one issue.”

The health ministry also sought to dispel doubts about the Serum Institute of India’s vaccine after a volunteer claimed that he had faced “severe adverse effects” after being inoculated during a trial “[The] adverse event will not affect the timeline [of the vaccine] in any manner whatsoever,” Bhushan said.

Serum Institute’s CEO Adar Poonwalla had said on Saturday that his firm was preparing to apply for emergency use of its vaccine in two weeks. He also said that the Centre was likely to buy 300-400 million [30 to 40 crore] doses of the vaccine by July 2021, though it did not sign a written agreement with the firm.

The Serum Institute has tied up with the British-Swedish pharmaceutical company AstraZeneca and Oxford University to produce a vaccine in India. The vaccine is seen as offering one of the best hopes for many developing countries because of its cheaper price and ability to be transported and stored at normal temperatures. Bharat Biotech in Hyderabad and Zydus Cadila in Ahmedabad are also working on a vaccine.

India has not signed a deal for a coronavirus vaccine yet so it is unclear when it will be available for use in the country. Availability of the vaccine in India will be subject to approval by domestic regulators, and the Indian government agreeing to purchase them. So far, many other nations including the United States, United Kingdom, the European Union, Australia and Israel have made deals to buy millions of doses of the vaccine.

Union Health Minister Harsh Vardhan had on Monday said that the Centre has planned to inoculate upto 30 crore Indians against Covid-19 by August next year, adding that he expected to be available by mid-2020.

India has reported 94,62,810 cases and over 1.37 lakh deaths so far. As many as 88,89,585 people have recovered from the infection so far.

Follow today’s live updates on the coronavirus here.