As India is all set to launch the “Precautionary Covid-19 vaccine” for a certain category of population from January 10, the Government on Wednesday made it clear that no mix and match will be allowed for the booster dose.
The Government asserted this in the wake of a few studies claiming that mixing doses of Covaxin and Covishield is absolutely safe. For instance, a study, conducted by AIG Hospitals along with researchers from the Asian Healthcare Foundation, has found that mixing of vaccines is absolutely safe and no adverse effect on participants was noticed.
However, Dr Dr VK Paul, member (health) of Niti Aayog made it clear at a Press briefing here that the “precaution shot” will be the same as the original jab. Healthcare, frontline workers and people above the age of 60 with comorbidities will be eligible for the precaution dose which would be administered from January 10.
“Precautionary Covid-19 vaccine dose will be the same as has been given previously. Those who have received Covaxin will receive Covaxin, those who have received primary two doses of Covishield will receive Covishield,” Dr Paul said.
Further, health officials also said that the upsurge of Covid-19 cases is happening in cities and the Omicron variant is the predominant circulating strain.
For the study, conducted by AIG Hospitals along with researchers from the Asian Healthcare Foundation, Covaxin and Covishield were mixed and tested it on 330 healthy volunteers. These volunteers were neither vaccinated nor had any history of Covid-19 infection.
The researchers divided 44 people into four groups and were administered doses. They were observed for 60 days to see if there are any adverse effects. The study found that the Spike-protein neutralising antibodies were significantly higher in the mixed vaccine groups when compared with the same-vaccine groups.
“Spike-protein neutralising antibodies are the ones which kill the virus and reduce the overall infectivity. We found that when the first and second dose are of different vaccines, the Spike-protein antibody response is four times higher compared to two-dose of the same vaccine,” said Dr D Nageshwar Reddy — chairman, AIG Hospitals — who was among the researchers involved in the study.
“Mixed doses can certainly boost these Spike-protein neutralising antibodies and will enhance the vaccines’ effectiveness even against the Omicron variant,” Dr Reddy added.