The effectiveness of Covishield’s vaccine against COVID-19 infection in fully vaccinated individuals was found to be 63% between April and May, when the second wave was at its peak in India, according to a new study.
It was published in The Lancet Infectious Diseases and included a comparison between 2,379 cases of confirmed infection with SARS-CoV-2 and 1,981 controls.
The vaccine’s efficacy against SARS-CoV-2 infection in fully vaccinated individuals was found to be 63%.
The Ministry of Science and Technology shared the study in an official statement.
More importantly, the scientists also observed that the spike-specific T cell responses were conserved against both the delta variant and wild-type SARS-CoV-2. Such cellular immune protection could compensate for the decrease in l ‘humoral immunity against virus variants and prevent moderate to severe illness and the need for hospitalization,’ the study said.
The ministry said the study provides comprehensive data on the vaccine’s real-world efficacy and immunological response to vaccination that should help guide policy.
A multi-institutional team of Indian researchers led by the Translational Health Science and Technology Institute (THSTI) evaluated the actual effectiveness of the Covishield vaccine during the outbreak of SARS-CoV-2 infection between April and May 2021, in India.
They also evaluated neutralizing activity and cellular immune responses against the variants in healthy vaccinated individuals to understand the mechanisms of protection.