Time is right: Why India still has 12-16 weeks between Covishield doses

Difference between the effectiveness of a single dose versus two doses is not that large for protection from hospitalisation and severe disease.

Several countries have reduced the gap between doses of the Oxford/AstraZeneca vaccine (branded Covishield in India) to eight weeks in response to the emergence of the more transmissible Delta variant of SARS-CoV-2, the virus which causes Covid-19. Recent studies both in India and internationally have also shown greater effectiveness of two doses of the Oxford/AstraZeneca vaccine compared to a single dose, especially against the Delta variant. India, however, has not reduced the existing 12- to 16-week dosage interval for Covishield.

This is because India is in a different stage of the pandemic compared to the other countries using the same