New Delhi: India will revisit the dosage interval for Covishield vaccine and take appropriate action based on emerging data, NK Arora, chairperson of the working group of immunisation advisory body NTAGI, said Wednesday.
Describing the Covid-19 and vaccination situation as ‘very dynamic’, Arora said in a statement that emerging evidence and reports regarding efficacy of partial versus full immunisation are also under consideration.
On the decision to increase the gap between two doses of Covishield from four-six weeks to 12-16 weeks, Arora said the move was based on scientific decision and there was no dissenting voice among the National Technical Advisory Group on Immunisation (NTAGI) members.
“Covid-19 and vaccination are very dynamic. Tomorrow, if the vaccine platform tells us that a narrower interval is better for our people, even if the benefit is 5-10%, the committee will take the decision on the basis of merit and its wisdom. On the other hand, if it turns out that the current decision is fine, we will continue with it,” a Union Health Ministry statement quoting Arora said.
The NTAGI chairman also explained the reason behind widening the gap between the two Covishield doses. “The decision to increase the gap lay in the fundamental scientific reason regarding behaviour of adenovector vaccines,” he said.
In the last week of April, the data released by Public Health England, United Kingdom’s executive agency of the Department of Health, showed that vaccine efficacy varied between 65 and 88 per cent when interval is 12 weeks. “This was the basis on which they overcame their epidemic outbreak due to the Alpha variant. We also thought that this is a good idea, since there are fundamental scientific reasons to show that when interval is increased, adenovector vaccines give better response. Hence the decision was taken May 13, to increase the interval to 12-16 weeks,” informed Arora.
“We have a very open and transparent system where decisions are taken on scientific basis. The Covid-19 group took that decision, with no dissenting voice. This issue was then discussed threadbare at an NTAGI meeting, again with no dissenting notes. The recommendation was that the vaccine interval has to be 12-16 weeks,” Arora informed.
PNN & Agencies