In this photo illustration, a hand is holding a medical syringe with the words on the background of which is the omicron covid-19 variant.
Raphael Enrique | LightRocket | Getty Images
White House chief medical adviser Dr. Anthony Fauci said Tuesday that 226 cases of the highly mutated variant of omicron Covid-19 have so far been detected in 20 countries, but US officials have yet to confirm the case in the states.
The variant, which first appeared in South Africa about a week ago, has over 30 mutations in the spiny protein alone. It’s a key part of the virus that allows it to bind to human cells and infect the body, and makes scientists worry that it will be far more infectious than the highly contagious delta variant that has caused a spike in cases around the world in recent months.
“This mutation profile is very different from other options of interest and concern, and while some mutations are also found in the delta, this is not a delta,” Fauci told reporters at a White House Covid-19 working group briefing. “These mutations have been associated with increased transmissibility and immune evasion.”
There are several other mutations in the virus that scientists have not seen before and do not know how they will affect the behavior or spread of the virus, he said.
US authorities have stepped up genome sequencing of Covid cases in recent months, sequencing about 80,000 samples per week, up from about 8,000 a week earlier this year, said Dr. Rochelle Walenski, director of the Centers for Disease Control and Prevention.