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The new COVID-19 subvariant XBB.1.16 is marching so rapidly around the globe that the World Health Organization has officially added the strain to its “variants of interest” list.
While not officially named, the XBB.1.16 is being referred to as “Arcturus.” It has grown exponentially since appearing in India in January, and now accounts for 4.2% of global cases and 9.6% of cases in the U.S. The CDC has not issued an official watchlist designation for Arcturus.
The latest WHO summary highlighted XBB.1.16’s “immune escape characteristics,” predicting it will continue to account for more and more cases. However, “there is no early signal of an increase in severity,” the WHO concluded.
Anecdotal reports from medical professionals indicate that Arcturus may cause pinkeye symptoms in some cases, including in children.
Both the CDC and WHO reported at the end of last week that COVID metrics continued to decline. But the WHO warned that the overall numbers don’t provide an accurate picture of the state of COVID in the world.
“Contrary to the overall trend, important increases in reported cases and deaths continued to be seen in the South-East Asia and Eastern Mediterranean regions and in several individual countries elsewhere,” the WHO report said.
Cases in the WHO South-East region are up 654%, and in the Eastern Mediterranean Region they are up 96%. Deaths are increasing, as well. The WHO South-East region includes India, Nepal, Korea and eight other countries. The Eastern Mediterranean region includes Iran, Egypt, Pakistan, and 18 other countries.
Worldwide and also in the United States, the predominant strain remains XBB.1.5. The WHO says it accounts for 51% of cases globally, and the CDC attributes it to 79% of U.S. cases. XBB.1.5 has been the most common strain in the U.S. for all of 2023.
CDC: “COVID Data Tracker Variant Proportions.”
World Health Organization: “Weekly epidemiological update on COVID-19 – 20 April 2023, Edition 139.”