Extending intervals between vaccine doses could leave people vulnerable to infection by one of the Covid variants in circulation, Dr Anthony Fauci, the medical advisor to the United States President, told NDTV Friday.
Dr Fauci was responding to a question about recommended intervals in the light of revised guidelines by the Indian government last month.
“The ideal interval between doses for mRNA vaccines is three weeks for the Pfizer and four for the Moderna. The problem with extending intervals is that you become vulnerable to variants,” he said.
“… and we’ve seen that in the UK, where they extended that interval, in that period you can get infected by the variants. So we recommend staying on schedule,” Dr Fauci explained.
However, he also said it may be necessary “if you have a very small supply”.
Last month the government extended the gap between doses of the AstraZeneca vaccine (manufactured and sold in India as Covishield) to 12-16 weeks – from the existing six-eight weeks.
That was the second time in three months Covishield dosage intervals were widened; in March states and UTs were told to increase the gap from 28 days to six-eight weeks “for better results”.
Widening of Covishield dosage intervals have been linked to increased efficacy.
However, the changes came amid an acute shortage and sparked suggestions the government was trying to eke out stocks to give as many people at least one dose till supplies are replenished.
