Covishield dose gap may again be reduced, but only for people above 45

The gap is likely to be reduced but this will not be applicable for all adults. The new schedule will be for people above the age of 45 years, Centre's expert has hinted, reports said.

The government may again reduce the gap between the two doses of the Covishield vaccine, but this time it will only be for those 45 years and older, Mint reported. The decision may be taken in two to four weeks, Covid-19 working group chairman Dr NK Arora has said in an interview. The decision will be based on final scientific evidence.

Gap between Covishield doses might be again reduced, reports said. (Bloomberg)

The present gap between the doses of Covishield is 12 to 16 weeks for all adults. At the very beginning of the vaccination drive in India, the recommended gap between the two doses of Covishield was 4-6 weeks, which was increased to 4 to 8 weeks and then finally to 12 to 16 weeks.

The decision to increase the gap to 12 to 16 weeks met criticism as the move was interpreted as an attempt to manage the vaccine scarcity in the country at that time. Experts, however, asserted that the decision was based on the emerging international scientific studies, according to which a longer gap between the doses generated more antibodies. In these studies, it was found that the percentage of antibodies produced by the first shot of the vaccine is quite high. Hence, the next shot should be delayed allowing the first shot more time to work.

But soon after, India increased the gap between the two doses in June, new studies claimed that the effectiveness of the first shot of Covishield was overestimated earlier. This again followed a reduction in the gap of the two doses of Covishield in many countries. Indian experts have reiterated that the vaccination situation is dynamic and will change as new studies will emerge, but public health will get paramount importance in whatever decision is taken.

As Covishield is the same as the Oxford-AstraZeneca vaccine, international studies are available regarding the efficacy of each dose. Now, in India too, there are many studies on the effectiveness of the doses on the local population. “We have gathered data on the impact of vaccines and their dosage interval on different age groups and from different regions," Dr NK Arora has said.

While senior citizens are considered the most vulnerable to Covid, the age group between 45 and 60 is also at a greater risk than the rest of the population and the presence of co-morbidity factors may increase the risk.

When the government extended the gap between the doses of Covishield, it allowed some exemption to sportspersons going to represent India at the Olympics, individuals going abroad for studies, job etc.