No to vaccine mixing because current regime worked: Senior official

The decision to use the same vaccine as a precautionary dose which was taken at a "high level" meeting late on Thursday evening is based on the thinking that the existing regime has worked well for the Indian population so far.

The experts also await data on mixing of vaccines by Indian health institutes and hence "the government didn't allow mix and match of vaccines due to lack of data on the effectiveness of such a strategy," said a senior official on the condition of anonymity.

He said it has been seen that there is a "minimal risk" if the same dose is given as the third dose.

"Even the reactogenicity has been seen to be less. It has been seen that even common minor reactions like fever, swelling etc were much lesser in those who received their third dose so far," added the official. The government opened precautionary doses in January to people above 60 and for those who are immunocompromised and healthcare and frontline workers.

"The ministry has taken a decision on the scientific basis. There is scientific evidence that supports homologous vaccine regime," said Samiran Panda, head of epidemiology and infectious diseases at the Indian Council Medical Research (ICMR).

The official said it was considered important to open the third dose for about 10-15% people who are at a higher risk and as it's difficult to identify them, it was decided to open it for everyone above 18 years.