A full lockdown was ordered Wednesday at Laguna Honda Hospital, San Francisco’s 780-bed nursing home, as five staff members tested positive for the virus and officials scrambled to protect elderly and vulnerable residents.

As the city sought to reassure the public that it is taking the “appropriate measures” to contain the virus, staff members at Laguna Honda say they are working in an atmosphere of confusion, growing anxiety and shortages of crucial supplies.

On Wednesday, a fifth staff member at the nursing home tested positive for the new coronavirus, a second unit was placed under quarantine and the city health department barred residents from leaving the facility and coming back for fear that they may contract the virus outside.

Of the infected staff members, four are nurses and one is a porter. The porter has been on quarantine since March 5. The department publicly acknowledged that any staff members had contracted the virus this week.

None of the 750 residents had tested positive for the virus as of Wednesday afternoon, which is notable given that many of the elderly patients have underlying health conditions that make them particularly vulnerable to the illness. But the department said it has tested only 15 people with symptoms.

It is unclear if the staffers are getting infected at Laguna Honda or if they are contracting the virus outside. Any outbreak that took hold inside the 780-bed facility likely would be devastating; the majority of patients are over 65 years old with underlying health conditions.

The city took early steps to mitigate the risk at the hospital; since March 6, visitors and nonessential personnel have been barred from entering the hospital.

As the situation at Laguna Honda escalated Wednesday, Dr. Grant Colfax, director of the health department, did not mention Laguna Honda in his prepared remarks at an afternoon news conference; he mentioned it only in response to a question from a reporter.

“From the beginning, it (Laguna Honda) has been a key focus of the department’s efforts,” he said.

Colfax said the hospital has increased its screening of staff who may have come in contact with infected co-workers and that “all the proper precautions are being taken at this time.” The department also said front-line health workers have enough protective equipment to keep themselves safe — even though city officials put out a call for donations of masks, gowns and hazmat suits.

“All supplies, PPE and the like, have been centralized to ensure they are available to front-line staff when needed,” said Deirdre Hussey, a veteran spokeswoman in the city, who has been put in charge of communications for the hospital. “As a result, Laguna Honda, like many city departments, has centralized distribution. Laguna Honda is adequately supplied and PPE is available when staff makes a request.

The official remarks contradict the experience of some front-line workers on the ground.

In interviews with The Chronicle over the past week, multiple Laguna Honda medical professionals have said they don’t have enough N-95 respirators, face shields and regular surgical masks.

In a Wednesday email to city health leaders, Tim Jenkins, senior representative for the union that represents doctors at the nursing home, the Union of American Physicians and Dentists, asked for a current inventory of protective gear at Laguna Honda, including N-95 masks, surgical masks, shoe covers and face shields.

“Doctors I have spoken with are suffering significant anxiety created by the uncertainty of their safety at work due to a lack of information about the availability of personal protective equipment (PPE),” he wrote. The union representing nurses and other hospital staffers, SEIU Local 1021, made similar demands in a statement Monday evening.

Meanwhile, Quoc Nguyen, an administrator at the nursing home, posted a request on the site donateppe.org for “N95 masks, surgical masks, hospital gowns, hazmat suits,” noting that “Laguna Honda hospital is a 780 bed nursing home with a vulnerable population.” The site was created by UCSF students and other volunteers. Nguyen did not respond to a call and email requesting comment.

The lockdown means that residents no longer will be able to re-enter the hospital. They will continue to have access to outdoor areas of the 62-acre campus. The lockdown was to begin at 5 p.m. Wednesday and will last as long as California is under a stay-at-home order.

The city health department also mandated Wednesday that all staff in the city who come into contact with patients wear masks.

A medical professional at Laguna Honda said staff members are largely being left in the dark about the situation. The medical professional, who is not authorized to speak publicly and asked for anonymity, found out on Wednesday that another staff member was infected only because the professional read The Chronicle news feed.

The city’s “increasing secrecy is both baffling and infuriating,” the medical professional said.

Lizette Medrano, 36, said she is worried about her father, Jose, an 82-year-old resident of the nursing home who suffers from dementia. Medrano, a nurse at another local hospital, said Laguna Honda hasn’t sent her family any emails or letters about staffers testing positive for coronavirus.

“If employees are infected, most likely patients will be infected as well,” Medrano said. “We haven’t gotten any information from them.”

It is unclear how many doctors and nurses at Laguna Honda may be out sick themselves or on mandatory quarantine, the medical professional said. Some employees who work in South 5, one of the units placed on quarantine, called in sick Tuesday morning, the medical professional said: “Don’t know how many had COVID symptoms and how many were just scared out of their wits.”

An investigation is ongoing to determine how many people the infected staff members came in contact with. The South 5 unit and the South 4 unit are currently under quarantine. A total of 120 patients reside in both units, and they are being checked three times per day for any sign of infection, Hussey said.

Dr. John Swartzberg, an infectious disease expert at UC Berkeley, said it is now “terribly important” for the city to figure out exactly how the Laguna Honda staffers became infected.

“If they got infected outside the hospital, then we need to look at the patients to see who they may have exposed,” Swartzberg said. “And if they got it in Laguna Honda, then where did they get it and who is infected there that we need to know about?”

Trisha Thadani, Jason Fagone and Cynthia Dizikes are San Francisco Chronicle staff writers. Email: tthadani@

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