Scientists at the Indian Council of Medical Research (ICMR) have found that Covishield and Covaxin vaccines, though potent against the COVID-19 virus, appear to generate only half as many antibodies against the B.1.617 strain, The Hindu reported.
Both the vaccines in use in India presently are effective at generating an immune response against the coronavirus and that this drop in antibodies didn't rule out the potential impact of the jabs against the COVID-19 infections, a series of early reports authored by the scientists have clarified, the report mentioned.
Since January, the scientists at the ICMR-National Institute of Virology (NIV), Pune, have been collecting samples from the COVID-positive individuals and testing them for prominent variants, B.1.1.7 (first found in the UK), B.1.351 (first found in South Africa), P2 (first noticed in Brazil) and B.1.617 (first noticed in Indian), according to the report.
According to the report, when the NIV scientists tested the B.1.617 mutant on antibodies extracted from the blood serum of those who had taken two doses of Covaxin, they found roughly 55 percent fewer antibodies than that generated against B1. With Covishield, the Geometric Mean Titer (a proxy for the number of antibodies), against B.1 was 42.92 whereas against B.1.617 it was 21.9, again around half.
Scientists say protection against infection isn’t solely determined by the number of antibodies and the duration over which they wane, but also by the mobilisation of T cells, a class of defensive bodies believed to direct a more specific attack against the virus and destroy it. On the other hand, antibodies only block replicating virus cells.