Some 264 people have been hospitalized, roughly 70% of them homeless, in an outbreak that began last November

Fourteen people have died from an outbreak of hepatitis A in San Diego, and experts believe it to be the deadliest outbreak of the disease in the US in decades, the Guardian has learned.

In large part, the victims were homeless people who have had to contend with a lack of 24-hour public restrooms, even though hand-washing is one of the best defenses against infection.

The number of cases has exceeded other large outbreaks, said a Centers for Disease Control (CDC) spokesperson, and is “likely the most deaths in an outbreak in the US in the past 20 years”, the period in which the CDC has operated its electronic reporting system. In 2003, three people died and at least 124 were hospitalized after eating contaminated salsa at a Pennsylvania restaurant. In 2013, 69 people across 10 states were hospitalized after eating contaminated pomegranate seeds.

Yet in San Diego, 264 people have been hospitalized, roughly 70% of them homeless, in an outbreak that began last November, according to local health officials. Nine of the 14 deaths have occurred since mid-July.

The virus, which impairs liver function, causing jaundice, fatigue, joint pain and, in the most serious cases, death, is largely spread through food or water contaminated by fecal matter. Hepatitis A has a long incubation period – up to 28 days – which means people can spread the disease before they’re aware they’re infected.

A county spokesperson said epidemiologists have yet to determine the cause of the outbreak. Contaminated food is often the source of an outbreak, and Dr Rohit Loomba, director of hepatology at the University of California at San Diego, wondered if the source could have been food that groups distribute to homeless residents.

“My gut feeling is it was a common source where somebody might have given food to a group of homeless individuals,” he said. From there, the virus spread via personal contact. “They don’t have a clean water supply to wash their hands, and once they have hepatitis A, then they become a source for another person.”

Someone whose health is already compromised – by alcoholism, drug use or other illnesses – faces a higher risk of death from hepatitis A, Loomba said. He recommends that anyone who is homeless should get vaccinated.

Experts say that besides vaccination, thorough hand-washing is the best way to prevent the spread of the illness. But good hygiene is difficult for someone who is homeless, when public restrooms are scarce and few are open 24 hours. This is true of many cities with large homeless populations across the western US – there are only nine toilets for 1,800 people at night on Los Angeles’ Skid Row – and not least in downtown San Diego, where the only 24-hour restroom is many blocks from the largest encampments.

Facebook Twitter Pinterest Char Beglou eats her breakfast after spending the night in the park. Photograph: Dan Tuffs/The Guardian

On a recent Friday morning, Eric Arundel and Mike, who declined to give his last name, sat under a shade structure on the edge of Fault Line Park, where homeless people spend time next to high-end condos and bars. A pair of restrooms in the park has remained locked for months, despite the city paying the park’s developer $1.6m to keep them open – and clean.

Mike, who was wearing a baseball cap, tilted his head up to show a reporter his eyes, the whites tinged yellow; he had been told by workers at a clinic to stay hydrated and call 911 if his body aches and fatigue got any worse, and was due to return Monday to hear the results of a blood draw.

The men listed off names of homeless people who frequented the park and had fallen ill. Some remain hospitalized. One woman’s parents took her home to northern California. No one is sure what happened to a man named Dave, who was taken to the hospital a couple months ago.

Debbie Smith, sitting in a chair near Mike and Arundel, said said she got vaccinated after seeing several people fall ill, and fought with two acquaintances to get treatment. “As soon as they woke up and their eyes were yellow, I told them, ‘You better get to the hospital.’”

After media reports about the locked restrooms, city officials intervened, telling the developer to keep the restrooms open from 6am-9pm. But several homeless people told the Guardian on Friday that the restrooms were sporadically locked. In an email Friday evening, a city spokesperson said a park official would ensure the restrooms remained opened during posted hours.

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The speed of San Diego’s response has also come under scrutiny.

County spokesperson Tom Christiansen said local public health officials are working with the the CDC and California department of public health to try to bring the outbreak under control. Outreach workers are letting people know where to go for free vaccinations and educating people on how to avoid spreading hepatitis A.

And the county is in the process of securing a permit from the city to set up hand-washing stations downtown, a process that should be completed this week.

But homeless advocate Michael McConnell is incredulous that the hand-washing stations weren’t set up months ago, as soon as officials realized there was an outbreak.

“I’m no expert on proper responses to public health crises or viral outbreaks, but what I do see a pattern of is a lack of urgency when it involves homeless people, and this really seems to be no different,” he said.

“How hard is it to make sure there’s additional hand-washing stations?”

Three blocks east of Fault Line Park, where tents and makeshift shelters line the Interstate 5 onramp, a 26-year-old with curly hair and freckles named Sinead Law said that IV drug users were the ones falling ill.

While Law was talking, a woman pedaled up on a bike, asking for food. She said she’d just recovered from hepatitis A. “Dirty drugs,” she said, when asked how she got it.

A sturdy man named Crash, who said he weathered hepatitis A several weeks ago without needing medical help, thinks that it’s been the last two or three months that the virus has really taken hold.

“Now they can’t get rid of it,” he said.

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