Pfizer-BioNTech and Moderna’s mRNA-based vaccines provide “persistent” and lasting protection for years from Covid-19, says a new study in Nature publication on Monday.
“Our studies demonstrate that SARS-CoV-2 mRNA-based vaccination of humans induces a persistent GC (germinal centre) B cell response, enabling the generation of robust humoral immunity,” the authors said in an abstract of their study, referring to memory cells found in lymph nodes, where immune cells are educated to detect and fight the virus.
Booster doses of these vaccines would probably not be needed as had been previously felt necessary, unless the virus evolves way beyond its current variants.
Ali Ellebedy, an immunologist at Washington University in St. Louis who led the study, told The New York Times they did not look at the Johnson & Johnson vaccine, but he added he expected it to be less effective than the mRNA-based versions. Also not included, it appeared, was AstraZeneca, which retails in India as Covishield.
But the good news for India, which is battling a devastating second wave of Covid-19 driven in part by the new Delta variant of SARS-CoV2, is that it is engaged in talks at the highest levels to find a way to authorise Pfizer-BioNTech and Moderna vaccines.
Earlier research had indicated that only those who had survived Covid-19 infection and had been fully vaccinated acquired a persistent and lasting protection from the virus.
{{/usCountry}}Earlier research had indicated that only those who had survived Covid-19 infection and had been fully vaccinated acquired a persistent and lasting protection from the virus.
{{/usCountry}}After an infection, a specialised structure called a germinal centre forms in the lung, which serves as a school for memory B cells to recognise the virus. In vaccinated people, these germinal centres are formed in lymph nodes in the armpits.
“Everyone always focuses on the virus evolving - this is showing that the B cells are doing the same thing,” Marion Pepper, an immunologist at the University of Washington in Seattle, told the New York Times. “And it’s going to be protective against ongoing evolution of the virus, which is really encouraging.”