Covaxin may help in controlling the virus load and which in turn would most likely reduce the severity of the infectious disease, according to a study.
Covaxin is an inactivated whole-virion vaccine to fight COVID developed by Bharat Biotech. For the study, 97 SARS-CoV-2 unexposed individuals who had received the Covaxin up to six months after second dose vaccination were kept under observation. Scientists found that Covaxin induces robust immune memory to SARS-CoV-2 and its variants of concern that persists for at least six months after vaccination and induces memory T cells that can respond robustly against the variants. A study was conducted in a multi-institutional collaboration with THSTI Faridabad, AIIMS New Delhi, ESIC Medical College Faridabad, LNJP Hospital New Delhi, among others, Nimesh Gupta and his group at the National Institute of Immunology (NII), New Delhi, news agency IANS reported. The study has been supported under the IRHPA-COVID-19 special call by the Science and Engineering Research Board, a statutory body of the Department of Science and Technology.
Covaxin: What the Study Found
The study found that the Covaxin vaccine produces antibodies against Spike, RBD, and Nucleoprotein of the virus, just like in virus infection. However, analysis of both the binding and neutralising antibodies revealed a reduced recognition of variants of concern like Delta (India), Beta (South Africa), and Alpha (UK). The study has showed that the vaccine is capable of inducing memory B cells. The study has provided the first-ever evidence of the detailed traits of immune memory generated in human in response to an inactivated virus vaccine. The researchers also found that the vaccine showed potential of producing the SARS-CoV-2-specific T cells. Importantly, and unlike antibodies, the effectiveness of the T cells was well-preserved against the variants. Also, these virus-specific T cells were present in the central memory compartment and persisted up to six months post-vaccination.