As the coronavirus has spread across Oregon and around the country, many of the fatalities caused by the disease have been among those with underlying conditions.

People with previously existing ailments have been told to take extra precautions in some places — avoiding large crowds, staying away from anyone who appears ill and other forms of social distancing.

Specifically, according to the U.S. Centers for Disease Control and Prevention, these people are at higher risk for severe symptoms of COVID-19:

-- Anyone with heart disease, lung disease and diabetes. These are broad terms that apply to a number of ailments. For specific advice about your condition, talk to your doctor.

-- Pregnant women. While federal health officials do not have specific information indicating pregnancy causes higher risk for complications for those who contract COVID-19, pregnant women have shown a higher susceptibility to respiratory illness.

-- Anyone with a compromised immune system, including people over 60, whose immune systems are naturally weaker than their younger counterparts.

-- Those who are 60 or older and have an underlying health condition.

“That’s why it’s so important for older adults and people with underlying conditions to be prepared,” said the CDC’s Dr. Nancy Messonnier.

The CDC has recommended that older people avoid traveling and crowds. High-risk populations should also stock up on supplies, food and medicine.

But younger people who don’t have underlying conditions should still exercise caution, said Chunhuei Chi, director of the Center for Global Health at Oregon State University.

While older people may develop more severe symptoms, young people are just as capable of spreading the disease, even if they are asymptomatic.

“So far we know, in the range of 12 to 20 percent, people who are infected are perfectly healthy,” Chi said. “They may have no symptoms, but are still able to transmit.”

As of Tuesday, there were more than 650 COVID-19 cases in the United States, according to a New York Times database.

Washington has been hit the hardest, with 162 cases. Of the 22 deaths in Washington, 19 are associated with Life Care Center, a nursing home near Seattle.

There were 14 cases in six Oregon counties, as of Tuesday morning, from as far east as Umatilla County and as far south as Klamath County. Half of Oregon’s patients are 55 and older. The Oregon Health Authority hadn’t released new numbers yet Tuesday.

Chi said the recent spike in confirmed cases was likely due to an increase in availability of tests, not to an uptick in viral activity.

“In the last couple days we've seen a surge of cases because now we have the testing capability,” he said. “These new cases are not new. They were out there, we just didn't know.

Chi was critical of Oregon’s slow ramp up of testing capacity, noting that it's impossible to track the disease without adequate ability to test for it.

“The Oregon Health Authority has been conservative,” he said. “Too conservative.”

As of Tuesday, the state has tested only 179 people for COVID-19. Without an influx of testing materials from federal sources, Oregon could run out of testing materials by Wednesday, though officials said they were confident the materials would arrive in time to stave off a lapse in testing.

It’s important for everyone, including young people, to do their part to limit spread of the virus, Chi said. Frequent and vigorous hand washing, staying home if sick and limiting social contact are all ways that people at low risk can help protect those who aren’t so lucky.

Failing to do so could have dire consequences. If the virus continues to spread unchecked, it could put immense pressure on the health care system. There are only so many beds in intensive care units and so many ventilators for patients who experience extreme respiratory distress.

Beyond the physical capacity of health care facilities, a spike in severe cases could place an unmanageable burden on health care providers themselves, Chi said.

Doctors, nurses and other health care providers face the prospect of long hours and high levels of stress, all of which they must shoulder while also keeping themselves from contracting the virus. It’s a heavy load, Chi said, both physically and mentally, and those charged with providing care for the rest of us must be given adequate care themselves.

“Given the contagiousness of the disease, it has the capability of overloading or collapsing our health care system,” Chi said. “It is very important for government leadership to coordinate with health care providers on how to preserve our health care providers and keep them from being infected.”

-- Kale Williams; kwilliams@oregonian.com; 503-294-4048; @sfkale

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