Colorado’s mountain resort communities are facing “extensive spread” of COVID-19, and local leaders on Sunday urged residents and visitors to minimize social contact and stay put as officials take steps including first steps toward a community quarantine.

“We’re seeing extensive outbreaks in these communities,” said Rachel Herlihy, a Colorado Department of Public Health and Environment epidemiologist, addressing conditions in Eagle, Gunnison, Pitkin and Summit counties.

That was one of a number of new developments Sunday, nine days after the first case was identified in Colorado.

Statewide, the number of confirmed coronavirus cases climbed to at least 135 as 34 more people tested positive — the largest single-day jump to date. COVID-19 is now confirmed in 17 counties, Denver topping the list with 25, followed by Eagle with 24 and Arapahoe with 18.

Boulder County officials announced four more positive cases Sunday night, bringing the county’s total to seven.

CDPHE and Denver officials on Sunday night announced new recommendations to follow the latest new federal Centers for Disease Control and Prevention guidance that “for the next eight weeks, organizers (whether groups or individuals) cancel or postpone in-person events that consist of 50 people or more throughout the United States.”

State health officials also adjusted their virus testing, declaring there will be no drive-up testing on Monday. They said they’d begin appointment-only, drive-up testing on Tuesday at a site yet-to-be determined.

In Summit County and elsewhere, hundreds of samples have been sent to labs for processing, leading to backups and delayed test results. Local public officials say they’re anticipating confirmation that the virus is spreading inside resort communities.

Summit County officials on Sunday asked residents not to leave the county unless absolutely necessary. Gov. Jared Polis already has advised people outside mountain resort counties not to enter those areas if possible.

No-go recommendations are voluntary but county officials “are having very in-depth conversations with local law enforcement,” assistant Summit County manager Sarah Vaine said.

“People are being cooperative and compliant,” she said. “At this point, there is no plan to have checkpoints. This has been a recommendation from the governor’s office, not an order. We are asking people to do their best. More information will come out of the governor’s office in the days to come.”

The emerging strategy in Summit County on Sunday called for people experiencing mild symptoms to isolate themselves at home for 10 days until symptoms are gone, saving hospital beds for people at least 60 years old and those with chronic health conditions. A highly contagious respiratory disease, COVID-19 typically is more severe in older patients and those with underlying health conditions.

“We need to keep the hospital beds for those who need them most,” said county Commissioner Elisabeth Lawrence.

Summit County’s emergency manager Brian Bovaird said hospitals expect a surge but are not full now: “We are in good shape there.”

Hospitals have increased their capacity in recent days, he said, including adding some rooms that have negative pressure, in line with Centers For Disease Control recommendations.

“We can greatly increase the capacity of medical beds if needed,” Bovaird said.

Lawrence urged residents not to gather in groups “of any size” for the next two weeks.

“Please limit your shopping trips to only those essential needs and medications,” she said.

At the isolated mountain resort of Telluride, a National Guard team arrived Sunday evening to conduct coronavirus testing and help San Miguel County health officials make decisions.

Colorado’s first death from COVID-19 was confirmed over the weekend in Colorado Springs. El Paso County public health officials said the victim, in her 80s, might unknowingly have exposed scores of olders at a bridge club. Around 100 people from around southern Colorado attended a two-day tournament Feb. 29 and March 1 at this Colorado Springs Bridge Center and a game night March 3.

At least one other bridge player has since tested positive for coronavirus, said John Dukellis, a club director, and two others have been hospitalized with symptoms that have not been confirmed to be the virus. He said he’s been fielding calls from scared players.

“This group is going to be hard hit,” Dukellis said. “This is just the beginning.”

Some of the players came from group homes but most were living in private residences, said Michelle Hewitt, an El Paso County Public Health spokeswoman. County officials are working with facilities where people may have been exposed, Hewitt said. She couldn’t say how many facilities may be involved.

The virus’ spread from the woman to the second bridge player was the first confirmed case of “community spread” in El Paso County, which was dealing with four cases of COVID-19.

Five new cases were found in Jefferson County; four in Douglas, Denver and Eagle counties; three in Arapahoe County; two in Weld and Gunnison counties; and one in Garfield and El Paso counties, state health records showed. The location of one additional positive test result hadn’t been identified.

The new people infected range from teenagers to those in their 60s and 70s, state officials said.

Sunday’s test results include 25 from the state’s lab and five from private testing facilities. More than 758 people have been tested for the disease since late February.

Gov. Jared Polis on Saturday ordered all ski resorts to close for at least one week, and a number of school districts have extended their spring breaks, among many cancellations throughout the state and country.

Metropolitan State University of Denver officials announced Sunday that they’ll suspend in-person, on-campus classes immediately, following a decision last week to transition to online classes by March 30.

The novel coronavirus is spread most often when an infected person coughs or sneezes. Other people within 6 feet of the infected person are most at risk. Public health authorities have urged residents to avoid close contact with other people. Polis recommended canceling any gatherings of more than 250 people.

Common symptoms of COVID-19 include fever, cough and shortness of breath. The symptoms typically appear two to 14 days after exposure to the virus. Health officials said people who think they might be infected should contact a primary care doctor.

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