UPDATED: This file was updated at 2:02 p.m. on March 16, 2020, to include the rates of COVID-19 infection in four Colorado mountain counties.

People who recently visited or live in four mountain counties of Colorado should “minimize their contact with other people” because the new coronavirus is spreading so rampantly in those areas, state health officials said Sunday.

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Eagle, Summit, Pitkin and Gunnison are the four counties mentioned in the Colorado Department of Public Health and Environment’s alert.

They are home to the state’s most popular ski areas, including Aspen, Vail, Breckenridge, Keystone and Crested Butte, where thousands of people typically travel to ski or snowboard on any given day, many of them returning that same day to Colorado’s Front Range or areas around the country.

“Anyone who has been in Eagle, Summit, Pitkin or Gunnison counties in the past week should minimize all contact with other people, whether or not they are experiencing symptoms,” CDPHE said in its bulletin.

On Monday afternoon, the state health department said the mountain counties have extremely high rates of infection. Pitkin County has an infection rate of 61.4 per 100,000 people; Eagle County has a rate of 41.9; Gunnison County is at 40.7; and Summit County is at 6.9. These rates compare with 2.2 for the seven-county Denver metropolitan statistical area; 1.6 for Weld County; 0.6 for El Paso County; and 0.3 for Larimer County.

There are roughly 50 cases of COVID-19, the disease caused by the new coronavirus, in those four mountain counties. Eagle County alone has 24 cases, including four new cases announced on Sunday.

One Australian woman who visited Aspen several weeks ago has been linked to at least 10 cases in the resort community.

“We’re seeing extensive outbreaks in these communities,” Dr. Rachel Herlihy, the state epidemiologist, said in a written statement. “We are asking people to take this voluntary action to slow the spread of the disease in Colorado and keep people safe. If we do this now, our hope is that we can slow down the spread of this virus and lessen the potential stress on our health care systems and workers.”

The announcement from CDPHE comes just hours after Gov. Jared Polis, in an extraordinary move, ordered all ski areas in the state to close for at least a week. Polis has warned that high country hospitals are unprepared for the surge of COVID-19 patients they are expected to in the coming days.

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“Community transmission is likely increasing across the state, so these measures are important to implement everywhere but are particularly urgent for residents and visitors of mountain communities that are already experiencing high rates of community transmission,” CDPHE said in its bulletin.

On Wednesday, Polis warned anyone who is over age 60 or who is vulnerable because of a compromised immune system to abstain from traveling to Colorado’s mountains.

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People who visited the affected counties in the past week, or who live there, are urged to:

Stay home or in a comparable setting as much as possible.

Work from home if possible. “If you can’t work from home, maintain at least 6 feet of distance between you and your coworkers or customers,” CDPHE says.

Only go to public spaces for necessities such as groceries and the pharmacy.

Continue healthy, non-group activities like walking, hiking, jogging, cycling and other activities that maintain distance from other people.

Not gather in group settings.

Avoid mass gatherings.

Maintain distance (approximately 6 feet or 2 meters) from others.

“If you need to travel, use a private vehicle instead of taking buses, rideshares, flights, or other transportation that puts you in contact with other people,” CDPHE said.

Continue to operate critical business functions, such as delivery of goods and operation of businesses, with social distancing and additional safety measures in place.

Over the weekend, Colorado health officials announced one new coronavirus case each in Mesa and Garfield counties, which neighbor the counties identified as hot spots by CDPHE.

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