Riverside University Health System Public Health announced late Saturday the first case of locally acquired COVID-19, more commonly known as novel coronavirus.

The individual, who is not being identified because of confidentiality rules, tested positive for COVID-19 and is currently undergoing care at Eisenhower Health in Rancho Mirage.

Authorities from Public Health are following up on people who may have been exposed and an investigation is being conducted to determine how the person contracted the virus.

Officials consider this the second case of the illness to be recorded in Riverside County.

A former cruise ship passenger from Riverside County who was diagnosed with the virus recently is recovering at a Northern California medical facility. That individual has not returned to Riverside County since leaving the cruise ship.

“We have always known this was a possibility,” Dr. Cameron Kaiser, Riverside County's public health officer, said of the first locally acquired case. “We have been planning for weeks and are prepared to take the necessary steps to protect the health of our local community.”

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“Eisenhower Health is currently treating a patient who is considered a presumptive positive for coronavirus after testing by Riverside County Public Health," said Lee Rice, public information officer for Eisenhower. "The patient is in isolation and Eisenhower staff have taken appropriate precautions in the treatment of this patient. No further information about the patient will be provided at this time.

“We ask the community to remember that Eisenhower’s medical professionals treat patients with infectious diseases every day and are prepared to care for our community members. Eisenhower continues to work closely with Riverside County Public Health, California Department of Public Health and within CDC guidelines,” she said.

Last week, Riverside County officials activated a medical health department operations center to better coordinate public messaging and planning among other agencies in the community in preparation for the spread of the illness.

“We are trained and prepared to respond to these situations. We have been in communication with hospitals and health care providers in Riverside County and have provided them with the information and resources they need. Protecting the health of Riverside County remains our top priority,” Kim Saruwatari, Riverside County's public health director, said late Saturday.

On Friday, county officials announced that a Murrieta Valley School District employee was being tested for the coronavirus after becoming ill following a trip to an area where there was an outbreak.

In addition, authorities said, 71 students at Murrieta Valley High School who were believed to have had contact with that person were asked to stay home under self-quarantine.

The results of this person's test will likely be ready by the middle of this coming week, Riverside County Public Health Department Disease Control Branch Chief Barbara Cole said Friday night, adding that the 71 students will not be tested at this time.

Riverside County is not able to conduct tests locally, as the county’s public health lab is undergoing renovations. Instead, tests are being sent to a California Department of Public Health lab in Richmond.

The lab in Riverside County will need to be re-certified before being allowed to conduct its own tests, officials said. No word on exactly when that could happen.

In the meantime, Murrieta Valley High will be closed on Monday and could remain closed until the testing has been completed.

Kaiser said that while he agreed with the decision to close the school, he wanted to "reassure the students, families and staff at MVHS that the risk of transmission is low ..."

Workers began disinfecting the school on Saturday, according to Bill Olien, the district's deputy superintendent.

"We have a team of people who are disinfecting every surface on campus," he said. "This involves using industry standard products, letting it remain on the surface for the required time and then coming back and wiping it down.

"It is a very time-consuming process but, again, we are following the established procedures and best practices," he added.

Murrieta Valley Unified Superintendent Pat Kelley said "the health and safety of our students is our first concern."

In an email to staff and families, the district said school nurses will be available on Monday at 7:30 a.m.

Earlier Saturday, county spokeswoman Brooke Federico said 15 people had been tested for the virus throughout Riverside County. Of those 15 tests, 12 have come back negative and three were pending.

She declined to say where in the county the tests had been conducted, citing patient privacy.

As unease about the coronavirus has grown, organizers of a number of annual events that draw national and international attendees are weighing the risk the illness poses against the economic benefits these events reap.

Already, the coronavirus has spurred cancellations of conferences and large-scale events like Miami's Ultra Music Festival, an outdoor electronic music fest that had an attendance of 170,000 in 2019. South by Southwest Festival in Austin was cancelled on Friday afternoon. And the AFL-CIO announced Saturday that it had cancelled its March 12 Orlando, Florida presidential forum with Democratic contenders Joe Biden and Bernie Sanders.

Those same concerns are affecting the Coachella Valley Arts and Music Festival in the form of dueling petitions — for and against cancellation — on change.org, a website where users can start issue-oriented campaigns.

A petition calling for the cancellation of Coachella appeared this past Tuesday and received more than 8,000 signatures by Saturday night. About 600 people had signed the petition against cancelling Coachella.

Also on Saturday, a petition calling for the cancellation of the BNP Paribas Open, which begins Monday, popped up on the same site. The Indian Wells-based tennis tournament, which draws tens of thousands of national and international attendees and players to the Coachella Valley, starts on Monday and is scheduled to end March 22.

About 110 people had signed that petition as of Saturday night.

About an hour before health officials made public the first coronavirus case in the Coachella Valley, Palm Springs Mayor Pro Tem Christy Holstege posted a statement on Facebook urging those calling for the cancellation of this region's events to recognize "there is currently no need to panic about the risk in Palm Springs or the Coachella Valley. We are carefully managing our airport, convention center and our city. We have taken additional precautionary measures to protect public places."

Holstege, who is running for re-election in November, said any decision concerning cancellation of one of this region's large-scale tourism events "should be made by public health officials based on science, and we should be careful to ensure we’re making evidence-based decisions."

She continued: "So many local businesses, workers, and our main tourism economy depend on making most of their money for the year in season, especially in April. We should proactively plan and focus on public safety but we shouldn’t jump to rash conclusions not based on science and shut down thousands of jobs that people depend on and millions of dollars in our economy ..."

Holstege went on to say that while she is in favor of "contingency planning in case the Coronavirus hits us hard" she added that "families who rely on ... making money in season are seriously affected by all of this and we need to make sure we do not take any drastic steps to deprive hardworking families (of) their livelihoods..."

Updated Riverside County information about COVID-19 is available at www.rivcoph.org/coronavirus. The public is encouraged to call 2-1-1 and 800-CDC-INFO (800-232-4636) with any questions.

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

Desert Sun staffers Colin Atagi, Brian Blueskye, Shane Newell and Kristin Scharkey contributed to this report.