A study published by UK’s Health Department has found that two doses of COVID-19 vaccines are needed to provide “strong protection” against symptomatic infection from B.1.617.2, which is the COVID variant first identified in India, and has taken over as the “dominant variant of concern”.
The study, conducted by the UK Department of Health and Social Care’s executive agency Public Health England looked at the protection provided by two COVID-19 vaccines – Oxford AstraZeneca/Covishield and the Pfizer vaccine – against the B.1.6172 and B.1.1.7, the variant first discovered in the UK.
The study found that:
- the Pfizer-BioNTech vaccine was 88 per cent effective against symptomatic disease from the B.1.617.2 variant two weeks after the second dose, compared to the 93 per cent effectiveness against the B.1.1.7 variant.
- Two doses of the AstraZeneca vaccine were 60 per cent effective against symptomatic disease from the B.1.617.2 variant compared to the 66 per cent effectiveness against the B.1.1.7 variant.
- Both vaccines were 33% effective against symptomatic disease from B.1.617.2, three weeks after the first dose compared to around 50 per cent effectiveness against the B.1.1.7 variant.
The analysis had data from all age groups from 5 April and included 1,054 people who were confirmed to be infected with B.1.617.2. The data also covered those over the age of 65 since December 2020.
According to a The Indian Express report dated 20 May, B.1.617 is the most dominant variant found in over 20,000 samples tested in labs under the Indian SARS-CoV-2 Genomics Consortium.
On 13 May, the Centre extended the interval gap between the first and second doses of the Covishield vaccine from 6-8 weeks to 12-16 weeks, citing “real-life evidence” from the UK.
The Covishield vaccines account for over 90 per cent of the inoculations conducted in India since the vaccination drive began in January. Till 23 May, 19.5 crore people were inoculated in India, out of which over 15 crore had received the first dose, according to Health Ministry figures.
(At The Quint, we question everything. Play an active role in shaping our journalism by becoming a member today.)