A recent ICMR study suggests that mixing Covishield and Covaxin can provide better immunity. MUSBA HASHMI talks to doctors about what does this mean for the future of the virus

] In April this year, a man was allegedly given Covaxin as the first dose and Covishield as the second. It must have raised an alarm and created a sense of panic. But, who knew three months down the line, a study by Indian Council of Medical Research (ICMR) will suggest that this mix up provides better protection against the virus.

“We have always learned in our branches of medicine that giving two medicines is always better than giving the maximum dose of one medicine. Take for example, if you have high blood pressure, we prefer to add one more medicine to the first medicine if the blood pressure is not controlled, instead of increasing the first medicine’s dose to the maximum. This ensures that the side effects are lower because the lower doses you give the side effects are lesser,” says Dr Shuchin Bajaj, Founder Director, Ujala Cygnus Group of Hospitals.

He adds that we have seen in the case of vaccine also that mixing two vaccines is giving better results in terms of protection as well as in terms of lower side effects. “So, it is a good development and is giving us hope that we can also work on some other diseases based on this module of mixing the vaccine technology because mostly till now we have only one kind of vaccine for a disease, usually we do not develop another kind of vaccine at all. But in view of the massive number of patients and exposed communities to COVID we had worked on many vaccines parallely and that is why we had developed some vaccines on a different technology platform. So we have now understood that mixing these different technologies is giving us better results,” explains Bajaj.

Dr Deepak Verma, Internal Medicine, Columbia Asia Hospital, Ghaziabad, tells you that amid  the reports of shortage of COVID-19 vaccines in some parts in the world, a new study by the University of Oxford and ICMR says that mixing two doses of vaccines can have a good immune response. This can be a sigh of relief for India as well.

“If a person is not able to get the second dose of the same vaccine, a different vaccine can trigger a similar or even stronger immune response. Most COVID-19 vaccines are being given in two doses, but a number of studies now support the idea that two different vaccines can be mixed and they will still give good results,” adds Verma.

Alternating doses of AstraZeneca and Pfizer-BioNTech vaccines were used in the study by the University of Oxford. It was found that the mixed schedules of these vaccines induced high concentrations of antibodies against the SARS-CoV2 spike IgG protein when doses were administered four weeks apart.

“Further research will tell whether this rule will apply to all other three vaccines that India has approved. Overall, the finding of Oxford and ICMR study show that there is silver lining and mixing two vaccine will not only address the shortage but also eliminate the virus in a fast and effective way,” opines Verma.

With that being said, doctors agree that there has been no perfect vaccine till date that doesn’t have side effects, so apparently this cocktail of vaccines will also come with some.

“Every vaccine has got some side effect. And there is no perfect vaccine so far being developed in the world where there is no side effects reported. So, yes, even if a combination of vaccines will be taken, one can expect some side effect in terms of fever or pain at the vaccination site, but we shouldn’t be seeing the significant adverse effects,” says Dr Arunesh Kumar, HOD, Paras Chest Institute & Sr Pulmonologist, Paras Hospital, Gurugram.

Now, many of us might be wondering whether these mixed doses will help eliminate the virus sooner, Kumar believes it is too early to say so. “Vaccine does help in eliminating the virus. Perhaps it’s too early to say that. Further studies are required to answer these questions. It may be that if the mixing of the vaccine gives more antibody response, they may be more useful in eliminating the virus in the future. But again, at this point in time, we can’t answer these questions, as we don’t have significant number of patients who have been tested to answer this question,” says Kumar.