Omicron: Booster shots may be necessary in India, says top virologist

According to Jameel, Director, Trivedi School of Biosciences, Ashoka University, with the advent of Omicron the possibility of return to a life similar to pre-pandemic "now seems distant".

The Omicron variant, identified last month, is concerning due to its highest number of mutations among any variant so far, 50 in all, with 32 in the spike protein, making it significantly more transmissible than even the Delta variant.

More than 63 countries around the world have so far reported cases associated with Omicron.

"The nature of Omicron mutations suggests increased efficiency of infection, transmission and evasion of antibodies and interferon, an early innate antiviral response," the professor said at a webinar organised by the University.

Early lab results from South Africa and Us drug maker Pfizer showed about a 40- and 25-fold drop in virus neutralisation ability of the vaccine.

But various studies have shown that "booster shots increase the amount of antibodies and cut reinfection rates. Given these results, it is now time that India devises policies on booster shots and vaccination for children," Dr Jameel said.

More details about the virus -- its virulence and severity as well as vaccine escape -- will be clear in the coming weeks as studies are underway.

But what is clear so far is that this variant spreads more efficiently and can evade immunity even from an earlier infection of Covid-19 and vaccination.

At the same time, there are also some positive indications such as the severity of the illness being possibly less than that caused by Delta variant but this requires confirmation.

"In India, it is essential for us to now step up the vaccination programme to vaccinate around 15 per cent of India's totally unvaccinated adults and also administer the second dose to the remaining population," Gautam Menon, Professor of Physics and Biology at the varsity, said.

"Booster shots may be necessary, at least initially for frontline health care workers, those about 60 years of age and those who are immunocompromised, but others can wait for them."

Further, experts said more information is required about the use of the currently available Indian vaccines as boosters and also about how the two vaccines most used in India -- Covaxin and Covishield -- might perform against the Omicron variant.

They also noted that "cases in India will rise by early next year as this has been the experience of other countries with high levels of vaccination, such as Israel and the UK".

The best strategies to reduce the spread of Covid-19 still are mask-wearing, care for ventilation, physical distancing, and stepping up vaccination, the experts advised.