The government has decided to increase the interval between the first and second doses of Covishield to up to eight weeks in its ongoing vaccination drive against Covid-19.
- Covishield is Serum Institute of India’s version of AZD1222, the vaccine developed by AstraZeneca in collaboration with the University of Oxford.
- Some data from global trials of AZD122 suggests that extending the duration between doses to 12 weeks increased its efficacy much more.
- The Ministry of Health and Family Welfare took the decision on the recommendation of two expert groups – the National Technical Advisory Group on Immunisation (NTAGI) and the National Expert Group on Vaccine Administration for Covid-19 (NEGVAC).
- The groups, after looking into available scientific evidence from clinical trials of the vaccine, concluded that the protection that it provides against Covid-19 is “enhanced” if the second dose is administered between 6-8 weeks.