Recently, Dr NK Arora, chairman of the central government’s COVID-19 working group said that experts may start testing to see if mixing doses of two different COVID vaccines could boost immune response.
The government, however, went to clarify thereafter that there would be no mixing of vaccine doses.
Meanwhile, researchers around the world have been studying the effects of mixing COVID vaccine doses. A study in Spain, led by the Carlos III Health Institute in Madrid, found in its preliminary trial that vaccinating people with both Oxford–AstraZeneca and Pfizer–BioNTech COVID-19 could produce a potent immune response.
A UK study called Com-COV found that people in the mix-and-match groups had mild to moderate common vaccine-related side effects than those who received two doses of the same vaccine.
Countries like Canada, France, Norway, and Sweden, among others, have recommended mixing vaccine doses as some other countries continue testing.
The strategy is known as heterologous prime-boost COVID-19 vaccination, and adopted to mitigate “supply shocks or shortages that might otherwise reduce the speed of vaccine roll-out,” according to a study published by The Lancet in May.
Whether one can receive two different doses of the COVID vaccine can only be determined by extensive research, said Dr Vikas Maurya, head of department and director, pulmonology, Fortis Hospital, Shalimar Bagh. “Researchers are already studying the effects of mixing the vaccine shots. Further research is required to understanding if doing this will boost the immune response or reduce it. For now, what we can say is a Covaxin shot should be followed by a booster dose of Covaxin only; the same applies for Covishield,” he added.