Japanese researchers have submitted a new study showing that mRNA vaccines may actually enhance the infectivity of the Delta variant, making it completely resistant to the vaccine.

While the vaccines have shown to be effective against certain variants of concern (VOC), there is a “tradeoff “ that the same antibodies that offer vaccine-induced immunity make to also fuel growth of vaccine-resistant mutations, the researchers found. Specifically, these same antibodies can also “enhance the infectivity of SARS-CoV-2 by inducing the open form of the RBD (receptor binding domain).”

The researchers’ study examined the neutralizing and enhancing functions of these antibodies and found “an evolutionary pathway by which the Delta variant could achieve complete escape from vaccine-induced immunity, which provides important information for the design of next-generation vaccines.”

This information matters when making predictions for future mutations of the Delta variant, the researchers said, as “these results suggest that the Delta variant may acquire full resistance to BNT162b2 immune sera by acquiring additional mutations in the RBD that disrupt recognition of anti-RBD neutralizing antibodies.”

 SOURCE: medRxiv August 23, 2021