Almost 1,100 people in Oregon could be hospitalized with COVID-19 by mid-September, according to new modeling released Tuesday, nearly doubling the record from last winter’s surge.

That’s according to a new forecast from researchers at Oregon Health & Science University, which dramatically revised patient counts upward to match the record-setting pace of hospitalizations during Oregon’s fifth wave of COVID-19. The highly contagious delta variant, combined with slow vaccination uptake, has upended researchers’ expectations and is already straining hospital capacity across the state.

With 575 people hospitalized Monday with COVID-19, Oregon is on the verge of breaking its previous high mark from Nov. 30, when 584 people were hospitalized. Oregon has already surpassed the record for the number of COVID-positive patients in intensive care. The vast majority of people hospitalized with COVID-19 are unvaccinated.

OHSU typically releases its COVID-19 forecasts weekly but delayed last week’s projections until Tuesday. Officials since Friday have declined on three separate occasions to explain why they held back the latest forecast.

The model released Tuesday has been updated “to be much more severe than previous forecasts.” Researchers used that same terminology in the previous report, dated July 30, when the forecast projected COVID-19 hospitalizations peaking in September at just under 600.

But that previous forecast dramatically undercounted reality, with the state likely to be at about 600 people hospitalized with COVID-19 when state officials release the newest numbers Tuesday.

Although cases and hospitalizations have been rising for four weeks, Gov. Kate Brown has taken a hands-off approach to COVID-19 safeguards since lifting restrictions and mask mandates June 30. Her office has said repeatedly that local officials should decide whether to reinstate measures, with only Multnomah County adopting an indoor mask mandate, which takes effect Friday.

OHSU’s report from Tuesday explicitly calls attention to past statewide interventions, saying four key policy changes “directly contributed to changing the trajectory of occupied hospital beds.”

As of Monday, data from the Oregon Health Authority show that in the region that includes Portland, 95% of non-intensive care beds and 87% of intensive care beds are already occupied, which includes both COVID and non-COVID patients.

The situation is more alarming in other parts of the state where vaccination rates are lower and hospital beds are in shorter supply. Out of 47 ICU beds in the region that serves central Oregon, for instance, only three were available, according to state data from Monday. In southern Oregon, hospitals serving hard-hit Jackson and Josephine counties reported only four ICU beds available.

State officials have said about 90% of the people hospitalized with COVID-19 are unvaccinated or not fully vaccinated.