Oregon state and county health officials Friday reported nearly 100 new coronavirus cases, marking the largest increase of infections in a single day and bringing the number of confirmed COVID-19 cases in the state to 414.

The Oregon Health Authority also reported the state’s 12th death linked to the illness, an 82-year-old Marion County woman who died Wednesday at Salem Hospital. She had underlying medical conditions, state health officials said.

Residents in Clackamas (10), Columbia (1), Deschutes (3), Douglas (1), Jackson (2), Klamath (1), Lane (2), Linn (2), Marion (26), Morrow (1), Multnomah (22), Polk (4), Umatilla (1), Wasco (1), Washington (18), Yamhill (4) counties tested positive for the virus in the last 24 hours, the health authority said.

During that time, more than 1,650 new people received coronavirus test results — up slightly from 1,527 the previous day, which resulted in just 50 positive tests, according to figures published on the health authority’s website.

There are now known coronavirus cases linked to 24 of Oregon’s 36 counties: 122 in Washington County; 83 in Marion County; 67 in Multnomah County; 31 in Clackamas County; 28 in Linn County; 18 in Deschutes County; 11 in Yamhill County; 10 in Polk County; nine in Lane County; six in Jackson County; five in Benton County; four in Douglas and Josephine counties; three in Umatilla County; two in Clatsop, Klamath and Wasco counties; one each in Columbia, Grant, Hood River, Lincoln, Morrow, Tillamook, Union counties.

Of the cases, 170 people, or 41%, are under the age of 50, state figures show. Another 82, or 20%, are over age 70.

At least 102 of the state’s COVID-19 patients, or 25%, have been hospitalized at some point during their illness, according to the Oregon Health Authority, up from 90 the previous day. Thirty-one COVID-19 patients are currently on ventilators.

State health officials have reported 11 previous COVID-19 deaths in the state. They’ve included residents from Clackamas (3), Lane (1), Linn (1), Multnomah (2), Marion (2) and Washington (2) counties. All had underlying medical conditions, state health officials said, but didn’t release any details.

While state figures show nearly 9,000 people in the state have now received tests, reflecting a continued expansion of test processing at private labs as well as Providence Health & Services in Portland, countless more remain unable to obtain one due limited availability.

The state reported that of the 8,924 tests administered so far, 8,510 were negative.

Testing shortages remain a problem across the nation, not only in Oregon, creating a dramatic undercount of how many people actually are infected with the virus. Some Oregonians are waiting nearly two weeks to get test results.

At this time, health care providers, people 60 and over and those with underlying health issues or who are pregnant should be prioritized for testing in the state if they have COVID-19 symptoms, the Oregon Health Authority said in its latest testing guidelines, published Wednesday.

Others who exhibit the symptoms — such as a dry cough, fever or shortness of breath — are being asked by state and local health officials to contact a primary care physician, clinic or to self-quarantine at home.

The state discourages doctors from testing people who are asymptomatic, or have only mild symptoms.

Oregon Health & Sciences University has also said that it will soon launch a coronavirus hotline to answer questions from prospective patients, though a date has not been announced.

This story has been updated to reflect the following correction: An earlier version of this story incorrectly reported the total number COVID-19 cases, due to incorrect information provided by the Oregon Health Authority. On Saturday afternoon, the state confirmed to The Oregonian/OregonLive that officials had double counted one COVID-19 case earlier in the week.

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

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