People in the 18-59 age group will get free precaution doses of the Covid-19 vaccine at government vaccination centres under a 75-day special drive likely to begin from July 15, official sources said on Wednesday. So far, less than 1 per cent of the target population of 77 crore in the 18-59 age group have been administered the precaution dose. 

“A majority of the Indian population got their second dose over nine months ago. Studies at ICMR and other international research institutions have suggested that antibody levels wane around six months after the primary vaccination with both doses... giving a booster increases the immune response,” the official said.