A steep drop in COVID-19 infections nationwide was reflected Tuesday with 16 Oregon counties improving their infection risk levels.

Other than Multnomah, the largest county to not improve its level was Deschutes, which had already dropped to high-risk level in the previous report. The county showed significant improvement in cases and is on pace to move to the moderate tier on March 9.

Crook County dropped from extreme risk to high risk. Jefferson County remains at extreme.

Gov. Kate Brown said Tuesday that 10 of the state’s 36 counties were dropping off the extreme-risk tier. The moves mean that restrictions on businesses, dining and activities will be less strict on Friday for a long list of Oregon cities, including Prineville in Central Oregon.

Among the larger cities that will see fewer restrictions are Eugene, Salem, Medford, Beaverton, Albany, McMinnville, Ontario, Oregon City and The Dalles.

“We are seeing great progress in stopping the spread of COVID-19 across Oregon and saving lives,” Brown said. “Oregonians continue to step up and make smart choices.”

Five counties — Jefferson, Benton, Josephine, Douglas and Coos — remain at the extreme-risk level. That compares to 26 counties in late November at the height of the holiday spike in infections.

The state’s four-tier risk level rates counties at lower, moderate, high and extreme levels for COVID-19 spread.

Ranking is determined by measures including total cases, cases per 100,000 people and positive infection rate. The higher the level, the more restrictive the rules on businesses and activities.

The levels are adjusted every two weeks. The ratings announced Feb. 9 expire Thursday. The new ratings go into effect Friday. Announcement of the next level changes will be March 9 and will go into effect March 12.

Wasco County, made the jump all the way from the worst level, extreme risk, to the best level, lower risk.

Some of the state’s most populous counties improved their level, though Portland just missed the mark.

Washington and Clackamas counties near Portland moved from high to moderate risk. Neighboring Multnomah County, which includes Portland, was just above the cutoff point for cases per 100,000.

Major counties moving off the extreme-risk level list to high-risk level include Umatilla, Lane, Marion, Jackson and Linn.

Eastern Oregon showed improvement, with Umatilla moving from extreme to high risk. Union and Malheur counties made big jumps, going from extreme to moderate level.

The coastal counties were an odd split. Clatsop County (Astoria) posted the lowest number of COVID-19 cases in the state when adjusted for population: 30.5 per 100,000. The second lowest number was in Lincoln County (Newport, Lincoln City), with 37.3 cases. Both counties moved from high to lower risk level. Tillamook County remained at lower risk level.

Measuring the coastal infection rate is problematic because two counties, Lane and Douglas, stretch from the Pacific Ocean to the Cascades.

But the southern most coastal counties are the flip side of the virus rates in the north coast. Coos County remains in the extreme risk level, while Curry County (Brookings, Gold Beach) saw infections rise and its risk level increased from lower to moderate.

Three counties saw their risk levels increase due to rising infections. Douglas County, the state’s ninth most populous county, rose from high to extreme risk. Harney and Curry counties moved from lower to moderate risk. All three will have to reinstitute restrictions for a minimum of two weeks.

The highest infection rate was reported in sparsely populated Lake County, with 30.4% of tests coming back positive for COVID-19.

The Oregon Health Authority announced last week that it had mistakenly included infections from the Warner Creek Correctional Facility in the Lake County total, which is against state policy. The numbers were later revised. Lake County remains at a moderate risk level.

The risk levels are part of a spate of good news on the COVID-19 front.

Case have dropped 44% nationwide over the past 14 days, according to the New York Times survey of state health agencies. Deaths are down 28% in the same period.

Oregon was part of the trend, with a 34% drop in cases and a 54% decline in deaths.

Oregon continues to rank 49th out of 50 states on a key measure that averages cases over seven days and adjusts the number for infections per 100,000 people.

Oregon has 9 cases per 100,000. Only Hawaii, with three, had a lower mark. Among Oregon’s neighbors, Washington and Nevada each had 11. California was at 17. The worst rates were in South Carolina at 46 and New York at 38.

While public health officials are hopeful that the trend will continue as the slow pace of vaccination picks up in coming months. But experts remain concerned about a spate of variants that spread faster and may be more virulent. One first discovered in the United Kingdom has been reported in three cases in Oregon.

The Centers for Disease Control has forecast that the “U.K. variant” could be the predominate infection by the end of March. Another variant, from South Africa, has been shown in early research to be more virulent and deadly, and can possibly bypass the current Pfizer and Moderna vaccines.

Both companies are working on revisions of the vaccine to deal with the variants. The CDC has said even if some variants infect those who are inoculated, the vaccine will at least protect against severe and fatal symptoms.

Lower Risk (10)

Baker

Clatsop (Moved from High)

Gilliam

Grant

Lincoln (Moved from High)

Sherman

Tillamook

Wallowa

Wasco (Moved from Extreme)

Wheeler

Moderate Risk (10)

Clackamas (Moved from High)

Curry (Moved from Lower)

Harney (Moved from Lower)

Hood River (Moved from High)

Lake

Linn (Moved from High)

Malheur (Moved from Extreme)

Morrow

Union (Moved from Extreme)

Washington (Moved from High)

High Risk (11)

Columbia

Crook (Moved from Extreme)

Deschutes

Jackson (Moved from Extreme)

Klamath

Lane (Moved from Extreme)

Marion (Moved from Extreme)

Multnomah

Polk (Moved from Extreme)

Umatilla (Moved from Extreme)

Yamhill (Moved from Extreme)

Extreme Risk (5)

Benton

Coos

Douglas (Moved from High)

Jefferson

Josephine