Covid: What do we know about BA.4.6, the new Omicron sub-alternative already prevalent in some US states?

It was the CDC, the US government’s disease control and prevention agency, that put BA.4.6, the new variant of Omicron, on its list of “variants of concern” these days.

According to US authorities, the sub-alternative has been circulating for several weeks in the US and has already surpassed all other Omicron alternatives in four states: Iowa, Kansas, Missouri and Nebraska.

Last week, BA.4.6 already accounted for 4.1% of Covid cases nationwide. It was placed in the list of variables of concern because BA.4.6 showed “greater transmissibility, decreased treatment efficacy, and increased severity or decreased neutralization by antibodies,” according to CDC . definition.

BA.4.6 is not only found in the United States as it has been monitored in 43 other countries.

Little data available

Scientists currently have little data on whether BA.4.6 has the potential to be as transmissible as BA.5, another Omicron variant that is widely prevalent worldwide.

However, specialists agree that due to the few new mutations that exist, BA.4.6 “should not be more worrisome than BA.4/5”. This does not mean that it will be weak, BA.5 has been described as “the worst version of the virus we have seen since the beginning of the epidemic.”

If it causes an equally astonishing immune escape, with so many infections occurring again, BA.4.6 will further complicate the medical response to finally end this epidemic.

The next few weeks will reveal more about this alternative. But his response to Omicron’s vaccine updates is the most predictable.