LOS ANGELES – In big cities around the country, homeless people scrape by, often in deplorable, unsafe conditions.

The health threat posed by living on the street may not be confined.

From Los Angeles to Kentucky, across the USA, experts said, growing homeless populations are increasingly susceptible to outbreaks of contagious diseases, including typhus, Hepatitis A and Shigella.

"This is a good example of why homelessness is a public health issue," said Elizabeth Bowen, an assistant professor in social work at the University of Buffalo in New York. "When people don't have access to basic needs like food, shelter, clean water and sanitation, people suffer, and population health, on the whole, is worse off."

'Dangerous out there'

The Centers for Disease Control and Prevention said Americans with typhoid fever are usually infected abroad. But in Los Angeles, a Police Department employee assigned to the city's traditional homeless epicenter became infected by the bacteria that causes the potentially deadly illness last month, and two other employees showed symptoms.

The area, known for decades as Skid Row, is overrun by rats that feast on garbage left on the streets or in alleys. Rats were spotted a few blocks away inside City Hall. In one office, carpeting was removed as a precaution to protect from fleas, which spread typhus, or droppings they may have left behind.

"It’s a little dangerous out there right now," said Gaga Turner, 21, who said she has lived on Skid Row for three years. The vermin "crawl up everywhere."

Christopher Harris, 58, a homeless man who lives on Skid Row, said rats and other vermin are a concern, and drinking water and bathrooms are in short supply. When it's hard to find an available toilet, especially at night, "you go where you feel like going." He said hand sanitizer is one of the area's biggest needs.

More:Los Angeles County seeks action from city on toilets, rats and trash to combat homeless crisis

Only blocks from billion-dollar skyscrapers and government offices, those living in tents or makeshift shelters use small plastic buckets as toilets. The waste is transferred into open 5-gallon pails left at street corners for crews to pick up.

For water, some fire hydrants are fitted with fountains that inhabitants line up to use.

Los Angeles County health officials swept through the district this month, issuing 85 violation citations, and they asked the city to provide an adequate number of toilets, hand-washing stations and trash cans.

The county, plagued by low apartment vacancy rates and rising rents, saw a 12% increase in its homeless population in its latest count for 2019. The city was up 16% to 58,936, three-quarters of whom live on the streets or in cars.

In response to criticism after the report, Los Angeles Mayor Eric Garcetti said he has more than doubled the number being housed to 21,000. He said the city's homeless budget is $460 million, which he said is 25 times higher than four years ago.

Homelessness is not only a problem in Los Angeles.

Despite the strong economy, the Department of Housing and Urban Development's annual count of the homeless put the population nationally at 552,830 last year, up 0.3% from the year before. The number of unsheltered grew to 194,467, up 2.3%.

Public health danger

A Hepatitis A outbreak occurred late last year in Los Angeles. The contagious illness can cause vomiting, nausea and jaundice. It has shown up on the West Coast and around the nation, including Kentucky, Utah and New Mexico, traced to the homeless and drug use.

After cases of Hepatitis A took off in Louisville in late 2017, theliver disease spread across Kentucky, sickening more than 4,000, about half of whom had to be hospitalized, and killing at least 43.

Hepatitis A is spread primarily through fecal contact. Thorough, regular hand washing and vaccination are ways to prevent it, said Neil Gupta, incident manager for the disease for the CDC.

In Seattle, a single case of Hepatitis A in a homeless man sparked a mass inoculation campaign two months ago.

Last year, Seattle issued a public health warning for increased levels of Group A streptococcal infections, which cause skin irritation or strep throat and Shigella infections, which cause diarrhea and other gastrointestinal upset. Public health officials tied both to homelessness.

"People who view homeless encampments as something that's happening to someone else and not affecting the community as a whole are incorrect," said Steve Berg, a vice president for the Washington-based National Alliance to End Homelessness. "The whole community is at risk when you have these kinds of outbreaks."

'A human tragedy'

In downtown LA, the head of the business improvement district sobbed as she talked about the issue and the government inaction.

"It's a disgrace. We are not doing anything to alleviate a human tragedy," said Estela Lopez, executive director of the Central City East Association, which hires cleanup crews and private security for the businesses in the area struggling to stay afloat.

Every day, she said, the challenges stack up. "It is trash. It is rats. It is unchecked garbage ... (and) people using buckets for bathrooms. It is a threat to public health," Lopez said.

She said her crews pick up 5 to 7 tons of waste a day, including human excrement and used needles. The city's Public Works Department said its 149 crew members and supervisors, equipped with face masks, glasses and protective clothing, haul away 1,200 tons of trash and debris a month. Sidewalks are steam-cleaned and sanitized but quickly can become dirty again.

It could get worse. The City Council approved the settlement of a lawsuit brought by homeless advocates that prevents the city from limiting possessions of those living in sidewalk tents on Skid Row. Opponents of the settlement fear that the piles conceal food waste that bolsters the rat population.

"I am afraid for my health and for those who are out there working," Lopez said.

For homeless people, the risks are greater. Epidemiologic studies of homeless populations have found higher prevalence of HIV, hepatitis, tuberculosis and scabies. In France, doctors found it effective to provide homeless people with vaccinations against hepatitis A and B, influenza and diptheria, as well as providing syringes and condoms, according to a 2008 study. But no amount of health care can make up for a lack of housing, according to the National Health Care for the Homeless Council, which states that poor health is a major cause of homelessness and also exacerbated by it.

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The conditions underscore the need to find housing for the homeless, advocates said.

"If folks are concerned about their fellow citizens at all, they will see it’s not appropriate for people to be living their lives outside," said Julia Devanthery, staff attorney for the Dignity for All Project, part of the American Civil Liberties Union of Southern California.