Scientists discover 'weak spot' across all major COVID-19 variants

A team led by an Indian-origin researcher has discovered a key vulnerability across all major variants of SARS-CoV-2, the virus that causes COVID-19, including the recently emerged BA.1 and BA.2 Omicron subvariants.

The weakness can be targeted by neutralising antibodies, potentially paving the way for treatments that would be universally effective across variants, the researchers said.

The study, published on Thursday in the journal Nature Communications, used cryo-electron microscopy (cryo-EM) to reveal the atomic-level structure of the vulnerable spot on the virus' spike protein, known as an epitope -or part to which an antibody attaches itself.

Spike protein is used by the SARS-CoV-2 virus to enter and infect human cells. The researchers also described an antibody fragment called VH Ab6 that is able to attach to this site and neutralise each major variant.

"This is a highly adaptable virus that has evolved to evade most existing antibody treatments, as well as much of the immun