The government is planning to conduct a study that will see whether a single dose of Covishield provides enough protection against Covid-19. “This could be a new vaccination strategy,” he added.
Last month, the government approved the National Technical Advisory Group on Immunisation (NTAGI’s) recommendation that extended the interval between two doses of the Covishield vaccine to between 12 and 16 weeks.
The decision to extend the interval was taken after examining real-life evidence from the UK, the health ministry had said.
Balram Bhargava, director-general of the Indian Council of Medical Research, said that a lot of “scientific deliberation” had taken place.
He said before the decision was made, discussions were also held with the University of Oxford, which developed the vaccine with
. But data is scarce on the impact of such measures, and experts are split.
“It is understandable that shortage of vaccines might have led to a change in the vaccination schedule. However, now that the supply is easing up, the gap between the doses should be shortened. For people who need to go out of the country, this interval could be reduced to two months,” said Anoop Misra, chairman, Fortis C-Doc.
Noted epidemiologist Giridhara Babu said that “As per the results of the pooled analysis of four randomised trials presented in The Lancet, vaccine efficacy is 82.4% when the second dose was given at 12 weeks (84 days). In the absence of other evidence this would be reasonable to provide the second dose with 84 days interval,” he said.