Editor's note: The Star is making this story free to readers due to public health concerns related to coronavirus. Please consider a digital subscription to The Star so we can continue doing this important work.

Two more anesthesiologists and an administrator at Community Memorial Hospital in Ventura tested positive for COVID-19, the hospital’s CEO said Monday.

Another anesthesiologist at the hospital tested positive for the virus last week, said Gary Wilde, president and CEO of the Community Memorial Health System. Ventura County Public Health officials confirmed the four cases involving the hospital late Monday afternoon.

The transmission source is unknown, Wilde said.

The hospital is tracking possible contacts and reaching out to staff members and others who could have been exposed. Special sterilization with an ultraviolet light system has been performed in areas of the hospital frequented by the four people.

Screening of possible symptoms and temperature – already done for visitors and patients — is being started for employees entering the facility, Wilde said.

The hospital halted elective surgeries last week, limiting any recent interaction between the anesthesiologists and patients, he said.

'We don't know how it got into the hospital'

Community Memorial remains open. Its recent patients include two people who tested positive with COVID-19 and both have been discharged. Wilde said it is “very unlikely” the virus was spread by patients.

“We don’t know how it got into the hospital,” he said, noting it appears all four people who tested positive attended the same meeting.

Staff members who may have been exposed are being asked to wear masks at work and to monitor themselves for 14 days, said Wilde.

Coronavirus:Threat brings social distancing to Ventura courthouse

None of the four people have exhibited severe symptoms, he said. All are quarantined in their homes.

Also Monday, six local patients total were hospitalized due to the coronavirus, county officials reported, as the tally here climbed to 35 cases. The number of positive cases went up by five compared to a day earlier.

Ventura County coronavirus update

On Sunday, Ventura County reported its first death from the virus: a patient in his or her 70s who had underlying health conditions. No other details were made public.

Ventura County's cases are spread around the county, with the most in Simi Valley, where 11 people have tested positive. Thousand Oaks and Camarillo each have five cases.

Ventura has four, Oxnard three and Santa Paula two. Other communities have a single case of the virus: Moorpark, Ojai, Oak Park, Westlake Village and Somis, according to the county's most recent figures.

The cases have struck across the age spectrum. In the most vulnerable age range — 65 and older — nine locals have tested positive. Fifteen cases struck 45- to 64-year-olds. Seven people age 25-44 have tested positive, as have three people age 18-24. A single local case was found in someone under 18.

The first local case was reported March 6 in a person who had traveled on the Grand Princess cruise ship.

The virus is present throughout the Tri-Counties area, which includes Ventura, Santa Barbara and San Luis Obispo counties.

As of 4 p.m. Monday, Santa Barbara County had 18 cases and San Luis Obispo County counted 33. In Los Angeles County, meanwhile, 536 cases and seven deaths have been tallied, public health officials have reported.

On Monday, typically a work day when roads and freeways might be clogged with cars at times, traffic was light on Highway 101 and other major corridors. State and local officials last week issued stay-at-home orders that have many locals working at home or missing work altogether as non-essential businesses have been closed.

People have been asked to "social distance" by staying at least 6 feet away from each other to help slow the spread of the virus.

As a reminder, he Ventura County Sheriff's Office sent out an emergency alert Monday afternoon to cell phones in the region, reminding people to self isolate and practice social distancing when outside the home for essential services only.

Tom Kisken covers health care and other news for the Ventura County Star. Reach him at tom.kisken@vcstar.com or 805-437-0255. Gretchen Wenner covers breaking news for the Ventura County Star. Reach her at gretchen.wenner@vcstar.com or 805-437-0270.