New BA.4.6, a subvariant of the Omicron COVID-19 variant that is quickly gaining traction in the United States, is now confirmed to be spreading in the United Kingdom. According to the latest briefing document on COVID-19 variants from the UK Health Security Agency (UKHSA), BA.4.6 has accounted for 3.3 percent of samples in the United Kingdom. The variant has since grown to make around 9 percent of sequenced cases.
According to US Centers for Disease Control and Prevention (CDC), BA.4.6 Omicron Covid-19 variant now accounts for over 9 percent of recent COVID-19 cases across the United States. The new COVID-19 variant is also identified in several other countries across the world. BA.4.6 is a descendent of the BA.4 Omicron variant, and it was first detected in January 2022 in South Africa, and has since spread around the world with the BA.5 variant.
The BA.4.6 variant will be similar to BA.4 in several ways, and it also carries a mutation to the spike protein, which is a protein on the surface of the COVID-19 virus that allows it to enter cells. This new mutation has been seen in other COVID-19 variants, and is associated with immunity evasion, meaning it helps the COVID-19 virus escape antibodies acquired from vaccination and previous infection.