Oregon researchers tracking the spread of COVID-19 anticipate a moderate peak in cases and hospitalizations in June.
Last week, the Oregon Health Authority predicted a subvariant known as XBB 1.16 was expected to cause “an increase in infections that will peak in June.” The OHA forecast cited data from Oregon Health and Science University.
COVID-19 rapid test kits, April 28, 2023. Researchers are tracking a news strain of COVID-19, similar to the omicron variant, as it spreads across Oregon.
Kristyna Wentz-Graff / OPB
OHSU data scientist Peter Graven put a finer point on the forecast in an interview on Friday on Think Out Loud. Graven said the new omicron subvariant, sometimes called “arcturus,” will push up numbers in the coming months. Graven is predicting a peak at 505 hospitalizations on June 28.
“That’s a bit speculative where I’m typing in parameters about what I think is the variant, what it’s done in India and other places and seeing what that would mean in Oregon. Getting the timing of a wave like that is tricky,” Graven said. “But we do think that there’s going to be some increase from this new variant.”
A peak of more than 500 hospitalizations would be triple the 161 COVID hospitalizations this week. But it’s far below the high point in September 2021, when the state’s hospitals were struggling under the delta wave, as nurses and doctors treated 1,178 patients hospitalized with COVID-19.
The predictions come as federal and state officials prepare for the sunset of the COVID-19 emergency declaration, coming May 11. In an April 21 press statement, OHA said health officials were prepared to “weather a subvariant wave” even as they prepared to wind down the pandemic response.
Graven said each new variant is slightly different but follows a similar pattern in penetrating people’s defenses.
“The new one finds a little crease, just enough to get past immunity,” Graven said. “It doesn’t mean that the entire population is now susceptible, but there’s going to be some percentage of the people who’ve had it who are now susceptible again.”
Researchers do not expect the new variant to cause more severe illness. Graven said that people who have previously gotten COVID-19 or have been vaccinated — or both — are less likely to be so sick that they require going to the hospital.
Longer term, Graven says variants are likely to keep coming, and unlike the flu, they won’t always arrive in a predictable seasonal pattern. But he said some variants will likely arrive with the cold winter weather, alongside RSV and the flu, as occurred last winter.