Update: The number of presumptive COVID-19 cases in Oregon rose to 21 on Wednesday night after state health officials announced two residents at a Lebanon veterans home in Linn County tested positive for the virus.

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The Oregon Health Authority on Wednesday reported four more presumptive cases of the novel coronavirus, bringing the number of COVID-19 patients in the state to 19.

A Deschutes County resident is among those who tested positive for the virus in the last 24 hours, marking the first known case in Central Oregon, according to state health officials. That person is being treated at the St. Charles Medical Center in Bend, an official at the hospital said during a news conference.

Polk County also reported its first case of the novel coronavirus, according to the state health authority. The two other new COVID-19 patients are in Marion and Umatilla counties, which each have prior documented cases.

Three of the four patients appear to be older than 55 and the other is between the age of 35 and 54, state health figures show. All but one were treated in hospitals at the time they were tested for the disease, according to those figures.

The new presumptive cases in Oregon come as reported coronavirus infections topped 1,100 nationwide Wednesday. The World Health Organization declared the global outbreak, which has killed more than 4,500 people, a pandemic.

In response to the growing alarm, Portland’s elected officials said they would relocate some vulnerable adults in homeless shelters to motels and limit large gatherings held by city bureaus.

Meanwhile, Portland State University became the first among the state’s public universities to encourage its 26,000-student campus to move to online classes for the remainder of the semester. Oregon State University and University of Oregon followed suit and required all classes be taught online.

Joe Fiumara, Umatilla County’s director of public health, said the second patient who tested positive in that county was a “close contact” of the first patient, an employee at the Wildhorse Resort and Casino near Pendleton.

The new patient is not currently hospitalized, but instead is self-quarantined at home, Fiumara said. He would not provide the second patient’s age range or gender. Fiumara said the first patient, a man, has been released from the hospital.

Fiumara said he couldn’t confirm or deny whether the first patient may have exposed the second patient after they were released from the hospital, but said the county had been monitoring the second patient for a long time.

“We fully expected this test to come back positive,” he said.

State health officials are uncertain how the people in Deschutes, Marion and Polks counties contracted the virus, and are considering those cases to be community-spread.

Marion County spokeswoman Jolene Kelley would not release any information about the county’s second patient, including the person’s age range, gender or condition.

Kelley said it was “likely” that other family members or associates of the infected person had been ordered to self-quarantine, but would not confirm how many.

Polk County's public health director, Kristty Polanco, said the county would not be releasing any information about the patient, whether they have been hospitalized, or how they are responding to the virus.

She said she understood residents may be frustrated that they’re not releasing more information, but that county officials believe doing so would compromise patients’ privacy. She said county officials have focused on identifying and contacting those who may have been in contact with the infected person.

State officials would not disclose any other information about the new patients or their conditions, but said they are working to identify anyone who had close contact with these individuals in the last 14 days.

“I know it’s difficult to learn that we are seeing more active community spread of COVID-19, but this is something we’ve been expecting,” said Dr. Dean Sidelinger, the state health officer and epidemiologist.

“It’s a good reminder to take steps to protect yourself and vulnerable friends and family members by washing your hands, covering your coughs and sneezes and staying home if you’re sick.”

Oregon’s first case was identified Feb. 28 – a male employee at Forest Hills Elementary School who lives in Hillsboro. A family member of his was subsequently diagnosed.

There are now COVID-19 cases in nine counties: eight in Washington County; two each in Jackson, Marion and Umatilla counties, and; one each in Deschutes, Polk, Multnomah, Klamath and Douglas counties.

Of the 19 Oregon cases, one has been confirmed by the U.S. Centers for Disease Control and Prevention, although all of them are being treated as if they were confirmed. Nine of the patients were hospitalized at the time they tested positive for the virus, state figures show, three more than on Tuesday.

People older than 55 account for 11 of the confirmed cases in Oregon, six others are between 35 and 54 and two are under 25.

Seventy-three more people in Oregon have tested negative for the virus in the last day, while another 62 are awaiting results, according to figures published to the authority’s website. To date, officials have tested 367 people in Oregon.

State officials have said there are likely hundreds of coronavirus cases in Oregon, and they continue to test people who show symptoms of the disease.

The Oregonian/OregonLive’s Piper McDaniel and Jayati Ramakrishnan contributed to this report.

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

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