Riverside County officials Monday announced 58 new coronavirus cases, bringing the countywide total to 291, with nine known fatalities.

The latest victim was a Moreno Valley man in his 50s, whose name was not disclosed, according to the Riverside County Department of Public Health.

“I am sure all Moreno Valley residents join me in offering condolences to this person’s family and friends,” Moreno Valley Mayor Yxstian Gutierrez said.

“We expected that coronavirus would eventually claim lives in our city, but each loss is a unique and tragic event that affects many people. Please continue to do the things we know work and we will save lives — stay home, practice social distancing and wash hands regularly.”

Riverside has the highest number of confirmed COVID-19 cases countywide, 29, followed by Palm Springs with 26 and Temecula with 24.

Seven of the COVID-19-related fatalities occurred in the Coachella Valley, in addition to a man in his 70s from Beaumont.

Public health officials last week released new estimates indicating coronavirus cases in Riverside County will continue to grow — possibly doubling every four to five days.

RUHS Dr. Geoffrey Leung said the surge — which could kill 1,000 people and infect 50,000 by early May — is expected to use up all the county’s hospital beds by April 12, and absorb the county’s supply of ventilators between April 22 and May 5.

Leung said he based his estimates on local approximations and nationwide trends.

The local mortality rate is slightly over 1%. More than 3,000 residents had been tested for the virus, as of Friday, and screening measures are being broadened, according to officials.

“I just want to be perfectly honest with you, and very clear with you, that we know that the surge isn’t even here yet,” Fourth District Supervisor Manuel Perez told constituents over Facebook Live on Friday afternoon.

Medical personnel began arriving Monday to staff the newly completed field hospital at the Riverside County Fairgrounds in Indio. Patients are expected to follow soon.

Members of the California National Guard last week quickly converted two existing buildings on the property into a 125-bed temporary hospital to be staffed by 30 to 40 doctors, nurses, technicians and volunteers.

County public health officials want the temporary hospital set up and treating non-critically ill patients — including those being treated for illnesses other than coronavirus — before the anticipated surge in COVID-19 cases hits.

Another temporary hospital is slated to be set up in western Riverside County.

Starting Tuesday, drive-thru COVID-19 testing in the Coachella Valley will relocate to the Riverside County Fairgrounds in Indio, near the temporary hospital is located.

Testing will be available by appointment only Tuesday through Saturday, from 9 a.m.-3 p.m., in parking lots 5 and 5A off of Arabia Street, between Highway 111 and Doctor Carreon Boulevard.

The site had been situated at the Southwest Church in Indian Wells since March 17.

“The fairgrounds is a large site and able to handle both operations of the federal medical station and the drive-up testing,” said Brooke Federico, Riverside County’s public information officer.

“The federal medical station will be in two of the buildings on the fairgrounds, and the drive-up testing will be conducted in one of the larger parking lots.”

Area residents can be screened for symptoms and, if deemed eligible, can schedule an appointment to be tested by calling 800-945-6171.

A second testing location at The Diamond in Lake Elsinore has operated since March 19, with appointments scheduled Sundays through Thursdays. Those looking to be tested at the facility must live within a 50-mile radius of Riverside.

A third testing location will open Wednesday at the Harvest Christian Fellowship church in Riverside, which will also be by appointment only, county officials announced.

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