The central government has lately come under a lot of criticism over the new rule that increased the gap between two doses of Covishield vaccine to 12-16 weeks, from the earlier 8-week gap, while there were no changes in the dosage interval for Covaxin.
The ambiguity over the decision has now been cleared by Dr Balram Bhargava, the head of Indian Council for Medical Research, who said that the gap between both the doses of Covaxin was unchanged as the immunity achieved after the first shot is not as high as the other vaccines.
Bhargava, justifying the Centre¡¯s decision to make the 3-month gap for Covishield mandatory, said that the immunity found after the first shot of the vaccine manufactured by Serum Institute of India was found to be strong.
However, the immunity level produced after the first dose of Covaxin is not as high and "this means the second dose should be taken after four weeks to ensure full efficacy", the TOI report quoted him as saying.
The ICMR chief further said that scientists and experts are still in the learning stages of what could possibly work best against the Covid-19 virus.
¡°Vaccines against Covid-19 first came on December 15. We are very new, and are learning¡trials are still on. It is an evolving science. By giving the first dose of Covaxin, you do not achieve too many antibodies. You achieve it after the second dose. With Covishield, antibodies are achieved at good levels,¡± Bhargava said, according to The Hindu.
Covishield, Covaxin and Sputnik V are the three vaccines that the DGCI has approved for emergency use in the country. Covaxin is an indigenous vaccine being manufactured by Hyderabad-based biotechnology company, Bharat Biotech.
Pune-based Serum Institute of India is manufacturing Covishield -- the local version of the Oxford-AstraZeneca COVID-19 vaccine. Sputnik V has been approved to be imported from Russia by Dr Reddy's but is yet to be widely available in the country.