UPDATE: State health officials announced six new presumptive cases of COVID-19 at a Linn County veterans’ home late Thursday night, bring the number of known coronavirus patients in Oregon to 30.

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The Oregon Health Authority on Thursday reported three new presumptive cases of the novel coronavirus, bringing the number of known COVID-19 patients in the state to 24 as top officials told residents to prepare for thousands more in the near future.

One patient who tested positive for the virus in the last 24 hours is a Clackamas County resident, state health officials said. That person, a man between the ages of 35 and 54, is a close contact with one of the state’s previous cases.

The two other patients are women who live in Washington County and are both older than 55, according to the health authority. The health authority is uncertain how they contracted coronavirus, and officials believe the women picked up the virus as it circulated in the community.

The latest figures arrived hours after Gov. Kate Brown formally announced a statewide ban on gatherings of more than 250 people and public health experts delivered a series of sobering statistics on the coronavirus’ spread in Oregon and the state’s continued struggles to test or track it.

During a press conference with the governor, Dr. Dean Sidelinger, the state’s epidemiologist, said he believed that as many as 250 Oregonians have already contracted COVID-19, a number that, if unabated, could surge to 75,000 by mid-May as cases doubled each week.

“We know that this is just the tip of the iceberg,” Sidelinger said of Oregon’s known coronavirus cases. “That’s why our state and local officials are taking action on social distancing.”

Meanwhile, the state public health lab can perform just 80 tests per day and will stick with testing only people who are hospitalized and seriously ill and people exposed to others confirmed to have the disease, Sidelinger said.

Commercial laboratories are now beginning to test additional Oregonians, said Sidelinger, who added that he did not know even a rough estimate of their capacity. He said multiple hospital systems in Oregon are also expected to begin testing for coronavirus, but they are still at least a week away from doing so.

There are now known COVID-19 cases in 11 counties: 10 in Washington County; two each in Jackson, Linn, Marion and Umatilla counties, and; one each in Deschutes, Clackamas, Douglas, Klamath, Multnomah and Polk counties.

Thirty-one more people in Oregon have tested negative for the virus in the last day, while another 96 are awaiting results, according to figures published to the authority’s website. To date, officials have tested 437 people in Oregon and another 252 are under monitoring for coronavirus symptoms.

Of the 24 Oregon cases, two have been confirmed by the U.S. Centers for Disease Control and Prevention, although all of them are being treated as if they were confirmed. Eleven of the patients were hospitalized at the time they tested positive for the virus, state figures show, two more than on Tuesday.

People older than 55 account for 15 of the confirmed cases in Oregon, seven others are between 35 and 54 and two are under 25.

This is a developing news story. Please check back for updates.

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

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