SALEM — The likely arrival of the new omicron variant and questions about its strength and speed are clouding an otherwise cautiously optimistic outlook of the course of COVID-19 in Oregon, according to a new state report.
The forecast from Oregon Health and Science University, released late Thursday, Dec. 2, shows the delta variant spike that hit Oregon over the summer and peaked around Labor Day continues a steady if stubbornly laborious decline in the state.
New infections, hospitalizations and deaths are falling, if not as quickly as forecast a month ago.
But projecting trends into the future is more difficult with the arrival of the omicron variant.
First reported by South African researchers on Nov. 25, it has now been found in more than 20 countries.
The Centers for Disease Control and Prevention confirmed Dec. 1 that an infection in California reported on Nov. 29 by a person who had recently traveled from South Africa was the first omicron case in the U.S. It has since been found in at least six states, from New York to Hawaii.
No cases have been reported yet in Oregon, though it's unlikely the virus would somehow skip the state. But continuing delta's drop is the main focus of public health officials until more is known about omicron.
"We don’t think it’s a big threat in Oregon because we don’t yet have a confirmed case and it will take time for it to spread,” said Peter Graven, director of OHSU’s Office of Advanced Analytics.
Scientists have been rushing to find out if the new variant is more contagious, more severe and can get around vaccinations or natural immunity from earlier exposures.
“It really comes down to vaccination,” Graven said. “If the vaccines work, we’re fine. If they don’t work at preventing hospitalizations, we may have to go back to protecting our vulnerable populations until we get a booster that effectively neutralizes the omicron variant.”
South African researchers reported Dec. 3 that omicron spreads twice as rapidly as the delta variant. But they differed on whether the cause was just rapid contagion or that omicron was getting around defenses of vaccines and earlier natural exposures.
Graven said that the infection situation in Oregon was quite different. About 82% of Oregonians have immunity, which includes both those vaccinated or recently infected.
At about 85%, Graven estimated the delta variant would be unable to create another spike because of the low number of unprotected people.
OHA reported this week that about 28.7% of new infections were in people who had been vaccinated — so called "breakthrough" cases. But the vaccines have kept the percentage of severe cases and death much lower than in unvaccinated people.
Those who have been inoculated account for about 4.4% of cases requiring hospitalization and just over 1% of deaths. The deaths of vaccinated people were primarily in those over age 80.
The delta variant, which drove a spike in infections, remains the main threat to Oregonians who are not vaccinated or were exposed naturally to the virus.
As of Dec. 2, the Oregon Health Authority reported 384 COVID-19 patients were hospitalized in the state. At the peak of the spike, hospitalizations hit 1,187 on Sept. 1.
OHSU forecasts have had to push out the date when the state would have under 200 hospitalizations, a key marker that COVID-19 levels were declining to pre-spike levels. The current projection is Feb. 1.
OHSU has said the decline of COVID-19 has been slower than originally forecast because of signs of pandemic "fatigue," with people resuming higher-risk behaviors, such as indoor gatherings and not wearing masks indoors.
With OHA statistics showing a steady drop in infections, Gov. Kate Brown recently lifted the requirement of wearing masks in outdoor venues and areas where social distancing was difficult.