Ever since the end of 2021, we’ve been living in Omicron’s world. It won out because it was easier to catch than any other COVID variant, whether you were vaccinated or not. That’s still true today.

Every major new COVID variant since then has been a sub-variant of Omicron. Since the beginning of 2023, the main sub-variant in the US has been XBB.1.5, also known as Kraken. As of this spring, two new sub-variants have become more and more common in the US, while Kraken has been losing ground. (You can see that change in the bar chart below, from the Centers for Disease Control (CDC).) They’re XBB.1.9.1 (Hyperion) and XBB.1.16 (Arcturus). Here’s what you need to know about them.

Hyperion (XBB.1.9.1)

• Not any more deadly or more likely to cause severe illness than other variants.

• If you get this variant, you’re less likely to get very sick if you’re up to date on vaccines.

• Levels right now are highest in the Northern and Central Midwest regions of the US.

Arcturus (XBB.1.16)

• Not any more deadly or more likely to cause severe illness than other variants.

• If you get this variant, you’re less likely to get very sick if you’re up to date on vaccines.

• Itchy or sticky eyes (also known as pink eye or conjunctivitis) are more common with this variant.

• Kids can get higher fevers with this variant.

• Levels are highest in the South Central, mid-Atlantic, and Northwestern regions of the US.

Variants Past and Future

The chart below, from the PANGO network, shows how Kraken, Hyperion, and Arcturus are related to one another, to the original Omicron variant, and to the original strain of the virus. 

Will we continue to see new variants in the future? Yes — the virus is still evolving really quickly. How quickly? About twice as fast as the seasonal flu virus, and about 10 times as fast as other coronaviruses that cause the common cold.

Okay, yeah, but does that matter? Right now, except for people who are elderly or whose immune systems don’t work well, we in the US have a decent “immunity wall” against COVID because so many people are vaccinated and/or have had the virus recently. That means we aren’t likely to get severely ill or die from the disease.

But according to expert virologists and epidemiologists the White House recently consulted, there’s about a 10 percent chance that the virus will change in a way that would break through that wall. (Ten percent doesn’t sound like a large number, but in epidemiology terms, it’s pretty big.) That’s why the World Health Organization, the CDC, and others continue to keep track of what variants are doing in the US and around the world. We all really want to be done with COVID. But even now, COVID may not be done with us.