AIIMS Director Dr Randeep Guleria on Saturday said people would have to be fully inoculated with two vaccine doses for protection against the more virulent Delta variant that is now fuelling the Covid-19 pandemic.
Research suggests one dose offers 33 per cent protection and both doses offer nearly 90 per cent, he pointed out.
"It is a cause of concern that the primary dose of the vaccine may not be enough to tackle the Delta variant. We might need to give the booster dose much earlier to ensure better safety," he said in an interview to news channel NDTV.
He said if you are vaccinated fully and come in contact with the virus you may still be infected, but the severity would be much lesser. Studies have shown that in most such cases the infection is milder and hospitalisation is not required.
As far as the Delta Plus variant of COVID-19 is concerned, Dr Guleria said the government is "closely monitoring" the situation, but it is the Delta strain that is of more immediate concern.
"We are very closely monitoring the Delta Plus variant but at the moment it is not the dominant variant in India. The Delta variant is. So we need to actively track it with genome sequencing to see how this variant is behaving in our population and prepare accordingly," Guleria observed.
So far 48 cases of Delta Plus COVID-19 strain have been detected in 11 states, according to figures compiled by the government till Friday.
Mixing Covid vaccines to counter potentially more aggressive and aggressive COVID-19 strains like Delta or Delta Plus is a "definite possibility" but more data is needed before a decision can be taken, the AIIMS chief said.
The government is considering this option and results of trials are likely in a few months, Dr VK Paul, Member (Health), NITI Aayog said recently.
Tests on mixed doses have also been conducted by countries such as Britain and Spain. The WHO has also said it is too early to reach a conclusion as yet.
Dr Guleria also said the third wave of infections in India is unlikely to be as severe as the second. However, at the same time he sounded a note of caution against underestimating the virus, saying, "we need to learn from the second wave to deal with the third."
Dr Guleria warned against rushing to lift restrictions that have been imposed to fight Covid-19. "Wherever in the country we notice even a slight surge, it should be a red flag. We need to take immediate measures in those areas rather than wait for it to spread," he observed.