Immunity

A study published in biorxiv by the Indian Council of Medical and Research (ICMR) ensures that the Covid-19 vaccine Covaxin (BBV152) of Bharat Biotech is effective against the Delta Plus (AY.1) variant of the coronavirus.

The researchers evaluated the IgG antibody titer and neutralizing potential of sera of Covid-19 naive individuals’ full doses of BBV152 vaccine, Covid-19 recovered cases with full dose vaccines and breakthrough cases post-immunization BBV152 vaccines against Delta, Delta AY.1 and B.1.617.3 in the study.

The study described, despite a slight reduction in neutralisation antibody titres, Covaxin is effective against Delta, AY.1 (Delta Plus) and B.1.617.3 variants. Dr Samiran Panda, head of epidemiology and communicable diseases, ICMR, referring to the study told that Covaxin could still neutralise Delta, AY.1 and B.1.617.3 variants.

SARS-CoV-2 Variant B.1.617.2 (Delta) variant has high transmissibility and is held responsible for the second wave in India.

Covaxin is a whole-virion inactivated SARS-CoV-2 vaccine. It is being used for mass immunization in the country and has demonstrated a 65.2 per cent protection against the Delta variant in a double-blind, randomized, multicentre, phase 3 clinical trial.

Eventually, Delta has further mutated to Delta AY.1, AY.2, and AY.3 variants. AY.1 variant was first detected in India in April 2021, which travelled to 20 other countries as well, described the study.

The study is in a pre-print stage and has not been peer-reviewed.

Bharat Biotech demonstrated 77.8 per cent effectiveness of Covaxin and 65.2per cent protection against the B.1.617.2 Delta variant while concluding the final analysis of Covaxin efficacy from Phase3 trials on July 3.