BETHESDA, Md. - Scientists at the National Institutes of Health said they have gained new insight into the COVID-19 alpha and delta variants, possibly explaining why the mutations are more transmissible and infectious than the original strain.Their study and findings were published online in the Proceedings of the National Academy of Sciences.Scientists said the outer surface of COVID-19 cells is decorated with spike proteins, which the virus uses to attach and enter host cells.
But before entering the host cell, the spike proteins of the virus must be activated by a series of cuts, or cleavages.NIH scientists said their study led them to believe that spike proteins of the alpha and delta variants produce more cleavages, making them easier.