Update: The number of presumptive cases of COVID-19 in Oregon rose to 51 late Thursday night after four more people at a veterans’ home in Linn County tested positive for the virus.

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The Oregon Health Authority on Monday reported eight new presumptive cases of the novel coronavirus, the largest increase in a single day, bringing the number of known COVID-19 patients in the state to 47.

Two people in Benton County and another two in Deschutes County tested positive for the virus in the last 24 hours, state health officials said.

The four other patients are residents of Clackamas, Marion, Multnomah and Washington counties.

There are now known coronavirus cases in 13 of Oregon’s 36 counties: 14 in Washington County; 10 in Linn County; six in Deschutes County; three in Marion County; two each in Clackamas, Jackson, Multnomah and Umatilla counties, and; one each in Douglas, Klamath, Polk and Yamhill counties.

Benton County issued a statement on Monday evening saying that while there were two Corvallis residents who tested positive for the virus, they had not been in the county since they were infected — they had been staying in Washington with relatives, and were infected by someone in that household. The county said those two people will stay in Washington until they have recovered.

State officials said they are preparing for thousands more in the coming weeks, even as they unveiled more dramatic measures to stem the pandemic’s spread.

Earlier in the day, Gov. Kate Brown announced she would ban gatherings of more than 25 people for at least a month and restrict restaurants and other establishments to serving takeout and delivery food only. Last week, she ordered the closure of all schools in the state from March 16 through March 31.

State health officials, meanwhile, said that based on new projections, Oregon hospitals may need an additional 1,000 hospital beds and 400 intensive care unit beds by April 11 to treat the 20 percent of people who become seriously ill from a coronavirus infection.

Thus far, one person has died from coronavirus in Oregon — a 70-year-old Multnomah County man, who, according to the Oregon Health Authority, had a preexisting health problems.

In Washington state, 48 people are known to have died from COVID-19 as of Monday, the most in the country. More than 900 people there have tested positive for the virus.

In the last day, 110 more people in Oregon have tested negative for coronavirus, while another 184 are awaiting results, according to figures published on the health authority’s website. To date, officials have tested 920 people in Oregon and another 352 are under monitoring for coronavirus symptoms.

People older than 55 account for 29 of the confirmed cases in Oregon, 13 are between 35 and 54, one is between 25 and 34 and four others are under 25.

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

Jayati Ramakrishnan contributed to this story.

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