As many as 1,154 healthcare workers took the second dose of COVID-19 vaccines on Saturday and 3,126 had taken the first dose when the vaccination drive began last month. Doctors here claimed on condition of anonymity that there could be some delays as international research has shown that Covishield, the primary choice of vaccine in India, is most effective when the second shot is administered after 12 weeks. “This could be a reason for the delay in rushing to the vaccination sites,” said a city-based nephrologist. Recently, the UK’s Joint Committee on Vaccination and Immunisation (JCVI), stated the research evidence was in favour of delaying the second dose to be given 12 weeks after the first to ensure better efficacy. Another preprint study with updated efficacy results also claimed that delaying the second dose beyond four weeks increases the level of protection. However, Health Secretary J Radhakrishnan, who received the second dose of Covaxin at Rajiv Gandhi Government General Hospital on Monday, said that ICMR guidelines and Drug Controller General of India (DGCI) suggested that second dose of the vaccine should be taken after 28 days. He urged the healthcare workers not to delay the second dose as it will only delay the immunity and antibodies formation. 

“We have to follow evidence-based research in the country and that suggests the second shot after 28 days,” he said. As many as 21,645 people received their first shot vaccine on Monday, including 15,717 healthcare workers, 3,309 frontline workers and 2,619 police personnel at 647 vaccination session sites. So far, a total of 2,69,017 people have been vaccinated.