New Delhi: A study by ICMR and Bharat Biotech has found that a booster dose of Covaxin, administered six months after a two-dose primary vaccination, showed higher immune responses against SARS-CoV-2 variants of concern, including protection against omicrons and critical illness . The emergence of the oomicron with at least 30 mutations within the target region of most vaccines – the spike protein – raised an alarm about its immune escape from the vaccine-induced neutralizing antibody, leading to increased infection and the risk of success and re-infection. The reason came, said the senior scientist. Dr Pragya Yadav, National Institute of Virology (NIV) in Pune told the media.

Additionally, reports of lack of antibody responses against emerging forms of the virus (VOCs) for other approved vaccines have raised concerns globally, she said. Antibody responses in the sera of 51 participants who received two doses of Covaxin as part of the study, given six months after the second dose and 28 days after receiving the third (booster) dose (on the 215th day of the second dose) Goi) and its effect was assessed against Omicron VOCs. The study was carried out by the Indian Council of Medical Research (ICMR) and covaxin maker Bharat Biotech in January and the findings were published in the Journal of Travel Medicine on March 24.

Another senior scientist at NIV, Dr. Gajanan Sakpal, said, “The antibody response was higher for participants administered with booster doses for B.1 and VOCs – delta, beta and omicron variants.” This indicates that the booster dose of Covaxin strongly triggered neutralizing antibody responses and efficiently neutralized multiple variants of SARS-CoV-2, Sakpal said.

“We conclude that neutralizing antibody responses after the third dose of BBV152/Covaxin against homozygous B.1 (19.11-fold) and other heterozygous strains (16.51-fold), Beta (14.70-fold) and Omicron (18.53-fold) VOCs were significantly had increased. providing assurance of a protective immune response of the booster in recipients,” the study said. “The data emphasize the need to speed up booster doses to individuals to deal with emerging VOCs and its consequences to protect against mortality, severity and hospitalization burden,” it said. The government on Friday announced that a precautionary dose of the COVID-19 vaccine would be available to all people over the age of 18 at private immunization centers from April 10.