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The U.S. has identified cases of the latest Omicron subvariant, dubbed “Centaurus” and known as BA.2.75 in the scientific community, according to Fortune.
Two cases have been detected in the U.S. so far, with the first identified on June 14, a spokesperson for the CDC told the news outlet.
The WHO announced this week that it has begun tracking the subvariant, which was identified in India in early June and has been reported in several other countries. BA.2.75 hasn’t yet been declared a variant of concern, WHO officials said, and researchers are still learning about the transmissibility, severity and potential for immune evasion.
The CDC doesn’t publicly report on emerging variants until they account for about 1% of cases. So far, cases of BA.2.75 are being reported on the CDC data tracker under BA.2 cases, which made up about 2.8% of U.S. cases last week.
The most prominent subvariants in the U.S. right now are BA.5, which accounted for 53.6% of new cases last week, followed by BA.2.12.1 with 27.2% of cases and BA.4 with 16.5% of cases.
In India, BA.2.75 is rising in prominence and is competing with BA.5 as the most contagious strain. So far, BA.2.75 has also been detected in Australia, Canada, Germany, New Zealand and the U.K.
Public health experts have posted on Twitter this week about the new subvariant, raising concerns about the potential for higher transmissibility and a better ability to escape vaccines.
Along with the usual Omicron mutations, BA.2.75 has nine additional changes, which could help the subvariant to spread more quickly and more broadly than previous Omicron subtypes.
At the same time, researchers can’t definitively say whether BA.2.75 will take over in countries where BA.5 is dominant, such as the U.S.
The subvariant “may just spread for some period of time until it runs into BA.5 and is outcompeted for people to infect,” Amesh Adalja, MD, a senior scholar at the Johns Hopkins Center for Health Security, told Fortune.
“I don’t know at this time that BA.2.75 will be anything more than a regional issue that eventually gets overwhelmed by BA.5,” he said.
Fortune: “Meet ‘Centaurus,’ the new ‘stealth Omicron.’ It was just found in the U.S. and may escape immunity more than any other COVID strain.”
WHO: “WHO Director-General’s opening remarks at the COVID-19 media briefing – 6 July 2022.”
CDC:”“COVID Data Tracker: Variant Proportions.”
Twitter: @WHO, July 5, 2022; @EricTopol, July 4, 2022; @PeacockFlu, June 30, 2022; EllingUlrich, July 3, 2022.