KOCHI: With tests proving its efficacy against most variants of the novel coronavirus, Covaxin — India’s homegrown Covid vaccine developed and manufactured by Bharat Biotech — has earned the support of experts the world over.As it has proven effective against the double mutated Indian variant, experts say that it would be wise to administer Covaxin to vaccinate those in the 18-44 age group. More so, since those in the younger age group are getting infected in the second wave. Earlier, studies by the Indian Council of Medical Research (ICMR) have found that Covaxin was effective against the UK variant.
The technologies adopted in manufacturing make the vaccines different from each other. Covaxin doses are made from the whole inactivated virus, and it can generate immunity against wide variants of the virus. Since Covishield is made from the spike protein of the coronavirus with adenovirus as the carrier, any major variation in spike protein can affect the immune response.
“How does one choose between Covishield and Covaxin? While I strongly urge people to get vaccinated with whatever vaccine is accessible to them, the theoretical advantages of Covaxin do hold some interest,” said Dr Anup R Warrier, infectious diseases expert.
He said the use of traditional technology suggests the possibility of fewer unexpected adverse effects, and the use of inactivated virus suggests a possibility of broader coverage of spike protein-focused mutants. “However, these may not be major considerations in the field, as vaccinology is a whole lot complicated. I expect to have clarity only from publications of real-world efficacy data from our country,” he said.
Bharat Biotech uses an age-old technology to produce Covaxin that has proven to be effective for many vaccines, including injectable polio and influenza (flu) vaccines.“It would be a great idea to vaccinate those in the 18-44 age group with Covaxin as infections in the second wave affect younger groups too, which may be due to a susceptibility to variants. In the case of Covishield, the beneficiary gains immunity only against the spike protein. As new variants are emerging, it may be less effective. But studies have proven that Covishield is equally effective against the virus,” said a senior infectious diseases expert.
Recently, United States’ top pandemic expert Dr Anthony Fauci had said that Covaxin neutralises the 617 variant (Indian variant) of the deadly virus. Meanwhile, the average prevalence of the UK variant surged to 30.48% of samples sequenced by April 25 in the state.
Scientists say that both Covishield and Covaxin are equally effective against the Indian strain. Patients show milder illness in case of infection post-vaccination. “Studies are going on across the world, and only new findings can shine more light on the efficacy against the mutated variants of the virus. So far, both vaccines are effective. Production of Covaxin is low, compared to that of Covishield. The antibodies generated after Covishield vaccination are also effective against the virus,” said Dr G Vijayaraghavan, vice-chairman and founder-director of the Kerala Institute of Medical Sciences.