Tests on mixing doses of vaccines and the effectiveness of a single dose of Covishield will begin soon in the government’s new strategy at a time of shortage of Covid shots.
All the vaccines currently authorised for use in India — Covishield, Covaxin and Russia’s Sputnik V — are two-dose vaccines. Sources say a study on mixing two different vaccines will start in a month and will likely be completed in two to two-and-a-half months.
“A platform is being established where three sets of administrative data in terms of diagnostic data, vaccine data and the overall disease data are to be harmonised. Based on that, we will look at effectiveness, reinfections and trends as coverage increases,” said Dr N K Arora, chairman of the Covid working group under the National Technical Advisory Group on Immunisation (NTAGI).
The idea is to study aspects like breakthrough infections following vaccinations and the severity of infections post-immunisation. “This will give an idea of how long you are likely to be protected from the disease after immunisation… It will also tell us the impact of increasing the interval between doses on vaccine efficacy and whether there is a need for modification either by increasing or decreasing the interval,” Arora said.
The platform, which is to be linked to CoWin, will allow people to flag their worries after a shot, after which a district officer will follow up on the cases.
The data may help the Centre decide whether to approve a single-dose regimen for Covishield.
