The World Health Organization has recently expressed concerns that the Delta variant of Covid-19, the variant first detected in India, is reducing the efficacy of the existing Covid-19 vaccines in the world. A new mutant of the variant has already been found in India, in Maharashtra's Jalgaon and Ratnagiri, following which the health ministry has asked Maharashtra, Kerala, Madhya Pradesh to be exercise caution.
Covid-19 variants have emerged as a cause of concern across the world as experts deliberate on the effectiveness of the vaccines to prevent the infection by the variants.
Covaxin and Covishield
Bharat Biotech's Covaxin and Serum Institute of India's Covishield are effective against the Delta variant, the health ministry has recently said. "Both the Indian vaccines, Covishield and Covaxin, which we are currently using in India, are effective against Delta. But to what extent and what is the proportion of antibody titers produced by these vaccines will be shared soon," Union health secretary Rajesh Bhushan has said.
The Russia-made vaccine, which became a part of India's vaccination drive, is effective against all variants of Covid known today, Gamaleya Centre head Alexander Gintsburg has said. "Antibodies developed after vaccination with Sputnik V protect from all variants of Covid known today, starting from the UK variant to the so-called Delta variant, first detected in India," he said. Sputnik has claimed better protection against new variants and that is why its marketer Russian Direct Investment Fund has proposed a booster shot to other vaccine makers, which will be the third shot after the regular two doses of vaccines.
Pfizer which is finalising the agreement in India to supply its vaccines is also known to be effective to some extent against Delta variants. But the protection is against hospitalisation; the jury is still out over whether it can protect against the infection. A recent analysis by Public Health England has recently revealed that Pfizer and AstraZeneca vaccines offer high protection of over 90 per cent against hospitalisation from the Delta variant.
Not much is known about the effectiveness of vaccines against Delta Plus as it is only an emerging variant. It has been found that Delta Plus is resistant to the monoclonal antibody cocktail treatment for Covid-19, which was recently authorised in India. But this does not tell anything about its response to Covid-19 vaccines yet.