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 on 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. This has been the case in the UK, he explained.
Last month, the Indian government had extended the gap between does of Astra Zeneca vaccine, which is manufactured and sold in India as Covishield, to 12-16 weeks - from the existing six-eight weeks.
This was the second time in three months that Covishield dosage intervals were widened.