For more than a month, France is facing the seventh wave of Sars-CoV-2 infection. After the Omicron BA.1 variant in early winter, then BA.2 in March, now BA.4 and BA.5 are causing a new spike in cases seen in early summer. “They’re kind of cousins to the BA.2explains Olivier Schwartz, Head of Virus and Immunity at the Institut Pasteur. BA.2 in particular has three mutations on the Spike protein that allow the virus to enter our cells, giving it a reproductive advantage. BA.4 and BA.5 carry the same mutations on the Spike, which allow for better binding to human cells, better transmissibility, and slightly better antibody disruption. This is what explains the resurgence of pollution.
All of these variants come from the Omicron version that appeared last December in France. Particularly contagious, they each caused waves of pollution the size of…
Source: Le Figaro
