The government on Wednesday defended the choice to enhance the interval involving two doses of the Covishield vaccine from 12 to 16 weeks saying it was based on a basic scientific purpose concerning behaviour of adenovector vaccines. This was a unanimous choice taken by the Covid-19 Working Group and Standing Technical Sub-Committee (STSC) of National Technical Advisory Group on Immunisation (NTAGI).
The government was responding to reports which recommended the choice to enhance the gap involving two doses of Covishield vaccine from 6-8 weeks to 12-16 weeks was not unanimous and that there had been some dissent amongst technical specialists more than this. The dissenting members had reportedly pointed to the lack of information to assistance extension of the gap beyond 12 weeks and have been more comfy with a gap of 8-12 week involving the two doses.
Around 90% of the total Covid-19 vaccines administered in the nation are Serum Institute of India’s Covishield vaccines. The dosage schedule was changed from 4 to six weeks in January to 4-8 weeks in March and then throughout April and early May the gap was six to eight weeks. On May 13, throughout the second wave of the pandemic, the interval was enhanced to 12-16 weeks. This was performed at a time when the UK decreased the gap involving the two doses to deal with rise in infections due to the Delta variant.
The 22nd meeting of Covid-19 working group of the NTAGI was held on May 10 to think about a proposal for a transform in the interval for Covishield applied below the national vaccination policy. The group advisable that ‘based on the actual-life evidences specifically from the UK, the Covid-19 working group had agreed to enhance the interval to 12-16 weeks involving two doses. This recommendation of Covid-19 working group was additional taken up for discussion in the meeting of STSC which was held on May 13. The STSC of NTAGI went by the Covid-19 working group recommendation and a dosing interval of minimum 3 months involving two doses of Covishield vaccine was advisable.
During each these meetings, the government stated no dissent was shown by any of the member, which includes Dr Mathew Varghese, Dr MD Gupte or Dr JP Muliyil. WHO had fixed the gap involving two doses for this vaccine at 12 weeks and the UK, as well, had a 12-week gap.