An ICMR study to examine the effect of Covaxin's booster dose has shown an increase in the levels of antibodies against SARS-CoV-2, Minister of State for Health told the Rajya Sabha on March 29.

International data available on booster doses of AstraZeneca and Covishield suggests a three- to four-fold increase in antibody levels after their administration, the minister said in a written reply.

"A study has been conducted by the Indian Council of Medical Research (ICMR) to examine the effect of a booster dose of Covaxin which shows an increase in the levels of neutralising antibodies against SARS-CoV-2 after the booster dose," she stated.

As per the recommendation of the National Technical Advisory Group on Immunisation (NTAGI), precaution dose is administered to healthcare workers, frontline workers, and people aged 60 years and above since January 10, 2022, she said.

As of March 24, 2022, 2.21 crore precaution doses against COVID-19 have been administered.