Newer COVID-19 subvariants show substantial escape from vaccination, previous infection immunity

Editor's Note

In a letter published in the New England Journal of Medicine, researchers at Beth Israel Deaconess Medical Center, Boston, report that the three Omicron subvariants (BA.2.12.1, BA.4, and BA.5) currently dominant in the US substantially escape neutralizing antibodies induced by both vaccination and previous COVID-19 infection.

The researchers evaluated antibody responses to multiple Omicron subvariants in 27 vaccinated and boosted individuals as well as 27 individuals who had previously been infected with COVID-19.

They found that neutralizing antibody responses to BA.4 and BA.5 were more than 20-fold lower than to the original WA1/2020 strain and were more than 3-fold lower than to the Omicron BA.1 and BA.2 variants.

These findings suggest that the Omicron variant has continued to evolve with increasing neutralization escape and can provide immunologic context for current surges caused by the BA.2.12.1, BA.4, and BA.5 subvariants in populations with high frequencies of vaccination and previous infection with BA.1 or BA.2, the authors note.