SALEM — The COVID-19 spike that began in July should peak soon after Labor Day and begin a two-month decline in infections, hospitalizations and deaths, according to a new state forecast.

The forecast Thursday, Aug. 26, from Oregon Health & Science University in Portland showed the rate of infections falling, along with hospitalizations and then deaths.

The “Census Forecast Primary Scenario” of hospitalizations has been a key statistic in the OHSU forecasts.

“The forecast shows a peak census level of 1,197 on 9/6,” wrote Dr. Peter Graven, the chief COVID-19 analyst at OHSU.

But Graven said the toll on the state has been heavy as the highest infection and hospitalization rates of the 18-month pandemic have pushed the medical system to the brink of breaking.

“We’re seeing the number of people hospitalized going up at rates we’ve never seen before,” Graven said.

No difference yet

Gov. Kate Brown’s order for mandatory mask-wearing at public gatherings and events inside has not shown to have dented the arc of infections.

“We had hoped to see the new statewide masking mandate make a difference in flattening the rate of infection, but we’re not seeing that yet,” Graven said.

There was hope in the forecast that the spike’s rocket-like trajectory may be coming to an end — but with a long, costly fall back to prior levels of cases.

The forecast indicates COVID-19 hospitalizations could fall to about 200 COVID-19 patients around Oct. 23. The decline would continue until falling back below pre-spike levels around Nov. 6. The forecast shows hospitalizations continuing to near zero by Dec. 25.

The Oregon Health Authority has reported that 95% of hospitalizations and deaths during the last two months have been among unvaccinated people.

Among vaccinated people with “breakthrough cases,” 5.5% have been hospitalized and 0.9% have died. The median age of the vaccinated people who died was 83.

OHA reported 2,057 new COVID-19 cases and nine new deaths Aug. 26. Oregon has reported 265,210 cases and 3,095 deaths during the pandemic. There have been just over 38.3 million cases nationwide and 633,451 deaths, according to the Johns Hopkins Coronavirus Resource Center. Worldwide, there have been 214.5 million reported cases and just over 4.47 million killed by the virus.

The latest surge in COVID-19 infections has been driven by the highly contagious delta variant. It was first discovered in India in May and swept across the United States in June and July.

It hit hardest in areas with large populations of people who were unvaccinated since the COVID-19 virus was first reported at the end of December 2019 in Wuhan, China.

Dr. Renee Edwards, OHSU’s chief medical officer, speaking Aug. 25 during a media briefing prior to the official release of the report, said the current crisis remains dire.

Hospitals reported over 92% of all adult staffed beds were occupied. Intensive care unit beds often had even fewer openings. Reports of patients backing up into emergency rooms and ambulances unable to bring in new patients came from around the state.

The death of a man in Douglas County waiting in an emergency room because not enough intensive care unit beds were available made international news.

Edwards said a graphic of the spike showed a roughly symmetrical rise and fall, with the increase from early July mirroring the projected drop over a similar period.

”The downward angle looks kind of exactly like the upward angle, that the path back down would look just as steep and long as the path up,” Edwards said.

Reaching herd immunity

OHSU scientists underlined that the forecast peak was not the end, but the middle of the current crisis. An equal number of unvaccinated people are expected to get sick during the next two months.

The 218 deaths in August so far are the fourth highest monthly total of the 18 months recorded by OHA, with the final total for the month unknown until midnight Aug. 31.

Progress toward improvement could stall if residents get “COVID fatigue” and become complacent about masking, getting vaccinated and other safeguards. The delta variant has increased cases 12-fold since early July.

Unvaccinated people are also a potential breeding ground for new variants, which could be even more contagious and virulent than the delta variant.

OHSU reported Aug. 26 that just over 63% of all Oregon residents are vaccinated. That includes children under 12, for whom there is currently no federally approved vaccine. Oregon ranks 19th in the nation for overall vaccination rate.

Edwards said that until most of the world is immune, variants could come from the next city or from around the world.

“That’s what viruses do,” Edwards said. “Viruses are constantly changing and mutating and looking for their best opportunity to spread.”

Oregon could approach herd immunity — in which the total number of people who are either vaccinated or been exposed to COVID-19 through transmission slows or stalls the ability of the virus to spread.

Edwards said that Graven’s forecasts have shown reaching herd immunity is possible — but at a much greater human cost than through vaccination.

“Dr. Graven said we are getting to herd immunity, but through mass infection, which is not the way to get there because too many people get sick, too many people die and it overwhelms our health care system,” she said.

The OHSU forecast is an estimate. The Aug. 18 report forecast hospitalizations peaking at 1,075 on Sept. 3. However, hospitalizations hit 1,080 on Aug. 25.

Brown has sent 1,500 Oregon National Guard troops to hospitals around the state, primarily for non-medical support of civilian staff.