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Federal authorities confirmed a coronavirus case — Ventura County's first — that was reported late last week, local officials said Tuesday morning.

A Ventura County resident who traveled on the Grand Princess cruise ship in February showed positive for COVID-19, according to tests conducted in a Ventura County Public Health laboratory. The test results were confirmed by the U.S. Centers for Disease Control and Prevention in Atlanta.

Ventura County Public Health Director Rigoberto Vargas told the Ventura County Board of Supervisors Tuesday that local authorities responded to the case as if it were 100% positive even before the CDC confirmation was received.

Public health officials have emphasized that risk to the community remains low, in part, because the case involved an exposure during travel and not a community transmission case where the illness was spread from person-to-person in the general public.

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Officials learned on Wednesday evening that six Ventura County residents traveled on a Princess Cruises' Grand Princess cruise from San Francisco to Mexico, ending back in the Bay Area on Feb. 21. A 71-year-old Placer County man who was also on the cruise died last week after testing positive for the coronavirus.

Public health employees started reaching out to the six residents on Wednesday night in an effort that drew praise from county leaders on Tuesday.

One of the six tested positive and became the county's first case of COVID-19. Another person showed symptoms but tested negative for coronavirus, showing no signs of the illness. The other four, including the spouse of the person who tested positive, showed no symptoms.

The passenger who was infected and the spouse remain in quarantine. The others completed their 14-day quarantine over the weekend and were told they can leave their homes.

Public and state health officials are working together to reach out to people who may have had contact with the infected traveler.

No information on any of the travelers' identities, or their residences, has been released. But the person who tested positive did visit the urgent care at the Center for Family Health on Arneill Road in Camarillo for treatment on Feb. 24, said Gary Wilde, CEO of the Community Memorial Health System, which operates the network of health centers.

Health system leaders learned of the exposure on Friday and placed six employees on temporary paid leave until at least 14 days from their late February exposure.

Out of an abundance of caution, Wilde said, they also started monitoring the health of a total of 40 employees and patients who were believed to be on a campus that includes the urgent care, a family health center and women's services at the same time as the person who tested positive.

Out of those 40, four people showed what Wilde called cold-like symptoms. Two tested negative, showing no signs of the virus. The tests for two others were still pending Tuesday afternoon, he said.

"Their symptoms are minor, and we expect negative test results. We are going through these extra steps to be absolutely sure," said Wilde in a text.

The Center for Family Health was not involved in the testing process for the infected cruise ship passenger, said Wilde. Vargas said the specimen was dropped off in a hospital parking lot, not identifying the hospital. Officials said earlier the infected person remained in the car to minimize any exposure.

Public health officials have reviewed all of the interactions between the traveler and medical facilities and determined all protocols were followed and no risks were created, said Ashley Bautista, the county's public information officer.

On Tuesday, county agency leaders laid out their work to supervisors in preparing for the coronavirus and trying to minimize the chance of spread. Dr. Robert Levin, the county's public health officer, noted the most common symptoms are fever, a dry and persistent cough and shortness of breath.

"There is a runny nose in only 4% of the cases. We're not seeing these people present with cold-like symptoms," he said, also emphasizing the importance of keeping a 6-foot buffer zone from people who are sick.

Public health officials said that while individual doctors can now decide on their own to order tests for their patients, authorities still recommend such steps only when symptoms are combined with a known exposure such as contact with a person who has tested positive or travel to a place where the virus is prevalent.

Though the state of California and Los Angeles County declared coronavirus emergencies last week, Ventura County Public Health will likely wait to initiate that emergency status until there is a confirmed case of community transmission, Vargas told supervisors Tuesday. Such transmission means the virus is spread in the general community as compared to transmission during travel to China or on a cruise ship.

Public health leaders would also think about initiating a local emergency process if both Los Angeles and Santa Barbara counties reported community transmissions, creating sort of a sandwich around Ventura County, Vargas said. Los Angeles County Public Health reported its first possible case of community transmission on Monday and has reported at least 17 total cases of coronavirus.

Santa Barbara County had not reported any cases as of Tuesday afternoon.

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Declaring a local emergency could bring measures, including the possible first roll-out of social distancing plans aimed at reducing interactions that could facilitate the spread of the disease. Schools, health centers, churches, nursing homes and businesses have all been asked by Ventura County Public Health to prepare such plans.

A local emergency would also mean that Ventura County Sheriff's Office of Emergency Services would launch an emergency operations center that would help manage a community-wide response.

Victoria Jump, director of the Ventura County Area Agency on Aging, said the agency is working on plans aimed at services for the elderly, including programs that deliver meals to homes. Though plans are still being developed, she said one possible option could involve leaving meals at a person's doorstep.

She also said the county is working with senior centers and flatly refuted a rumor that the county has ordered such facilities to close.

"It's not true," she said.

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Other governments are taking their own action. Starting Wednesday, the city of Oxnard will suspend senior center and some recreational programming but lunch will continue to be served to seniors.

“Basically, we’re being very proactive here,” said Katie Casey, spokeswoman for the city. “All seniors will still get their meals at this time. We’re just going to suspend programs temporarily.”

Youth boxing and programs for special needs residents will also be suspended until further notice. Other sports programs will continue.

Classes and events will be suspended for Wilson, Palm Vista and South Oxnard senior centers. Weekday lunches will continue to be served to those who currently participate in the nutrition program. For more information about the Oxnard senior centers, call 805-385-8019.

In February, a quarantine site was started at Naval Base Ventura County for U.S. citizen travelers who show no symptoms of coronavirus but visited China, heart of the outbreak. During two weeks, two people were quarantined at the site, one only briefly.

The other person, who visited China's Hubei province, completed his 14-day quarantine and was released to return home outside of California on Friday.

Melinda Lee Larson, public affairs officer at the naval base, said the agreement to keep the quarantine site operational has been extended to the end of the month.

She said the site's mission has not changed and that it will remain an option for travelers without symptoms who fly into Los Angeles International Airport and don't have a place locally where they can self-quarantine.

"We’re a funneling site for travelers coming out of LAX," she said.

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Staff writer Wendy Leung contributed to this report.

Tom Kisken covers health care and other news for the Ventura County Star. Reach him at tom.kisken@vcstar.com or 805-437-0255. USA TODAY also contributed to this report.

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