Headlines are flying after the Department of Agriculture confirmed that the H5N1 bird flu virus has infected dairy cows around the country. Tests have detected the virus among cattle in nine states, mainly in Texas and New Mexico, and most recently in Colorado, said Nirav Shah, principal deputy director at the Centers for Disease Control and Prevention, at a May 1 event held by the Council on Foreign Relations.

A menagerie of other animals have been infected by H5N1, and at least one person in Texas. But what scientists fear most is if the virus were to spread efficiently from person to person. That hasn’t happened and might not. Shah said the CDC considers the H5N1 outbreak “a low risk to the general public at this time.”

Viruses evolve and outbreaks can shift quickly. “As with any major outbreak, this is moving at the speed of a bullet train,” Shah said. “What we’ll be talking about is a snapshot of that fast-moving train.” What he means is that what’s known about the H5N1 bird flu today will undoubtedly change.

With that in mind, KFF Health News explains what you need to know now.

Q: Who gets the bird flu?

Mainly birds. Over the past few years, however, the H5N1 bird flu virus has increasingly jumped from birds into mammals around the world. The growing list of more than 50 species includes seals, goats, skunks, cats, and wild bush dogs at a zoo in the United Kingdom. At least 24,000 sea lions died in outbreaks of H5N1 bird flu in South America last year.

What makes the current outbreak in cattle unusual is that it’s spreading rapidly from cow to cow, whereas the other cases — except for the sea lion infections — appear limited. Researchers know this because genetic sequences of the H5N1 viruses drawn from cattle this year were nearly identical to one another.

The cattle outbreak is also concerning because the country has been caught off guard. Researchers examining the virus’s genomes suggest it originally spilled over from birds into cows late last year in Texas, and has since spread among many more cows than have been tested. “Our analyses show this has been circulating in cows for four months or so, under our noses,” said Michael Worobey, an evolutionary biologist at the University of Arizona in Tucson.

Q: Is this the start of the next pandemic?

Not yet. But it’s a thought worth considering because a bird flu pandemic would be a nightmare. More than half of people infected by older strains of H5N1 bird flu viruses from 2003 to 2016 died. Even if death rates turn out to be less severe for the H5N1 strain currently circulating in cattle, repercussions could involve loads of sick people and hospitals too overwhelmed to handle other medical emergencies.

Although at least one person has been infected with H5N1 this year, the virus can’t lead to a pandemic in its current state. To achieve that horrible status, a pathogen needs to sicken many people on multiple continents. And to do that, the H5N1 virus would need to infect a ton of people. That won’t happen through occasional spillovers of the virus from farm animals into people. Rather, the virus must acquire mutations for it to spread from person to person, like the seasonal flu, as a respiratory infection transmitted largely through the air as people cough, sneeze, and breathe. As we learned in the depths of covid-19, airborne viruses are hard to stop.

That hasn’t happened yet. However, H5N1 viruses now have plenty of chances to evolve as they replicate within thousands of cows. Like all viruses, they mutate as they replicate, and mutations that improve the virus’s survival are passed to the next generation. And because cows are mammals, the viruses could be getting better at thriving within cells that are closer to ours than birds’.

The evolution of a pandemic-ready bird flu virus could be aided by a sort of superpower possessed by many viruses. Namely, they sometimes swap their genes with other strains in a process called reassortment. In a study published in 2009, Worobey and other researchers traced the origin of the H1N1 “swine flu” pandemic to events in which different viruses causing the swine flu, bird flu, and human flu mixed and matched their genes within pigs that they were simultaneously infecting. Pigs need not be involved this time around, Worobey warned.

Q: Will a pandemic start if a person drinks virus-contaminated milk?

Not yet. Cow’s milk, as well as powdered milk and infant formula, sold in stores is considered safe because the law requires all milk sold commercially to be pasteurized. That process of heating milk at high temperatures kills bacteria, viruses, and other teeny organisms. Tests have identified fragments of H5N1 viruses in milk from grocery stores but confirm that the virus bits are dead and, therefore, harmless.

Unpasteurized “raw” milk, however, has been shown to contain living H5N1 viruses, which is why the FDA and other health authorities strongly advise people not to drink it. Doing so could cause a person to become seriously ill or worse. But even then, a pandemic is unlikely to be sparked because the virus — in its current form — does not spread efficiently from person to person, as the seasonal flu does.

Q: What should be done?

A lot! Because of a lack of surveillance, the U.S. Department of Agriculture and other agencies have allowed the H5N1 bird flu to spread under the radar in cattle. To get a handle on the situation, the USDA recently ordered all lactating dairy cattle to be tested before farmers move them to other states, and the outcomes of the tests to be reported.

But just as restricting covid tests to international travelers in early 2020 allowed the coronavirus to spread undetected, testing only cows that move across state lines would miss plenty of cases.

Such limited testing won’t reveal how the virus is spreading among cattle — information desperately needed so farmers can stop it. A leading hypothesis is that viruses are being transferred from one cow to the next through the machines used to milk them.

To boost testing, Fred Gingrich, executive director of a nonprofit organization for farm veterinarians, the American Association of Bovine Practitioners, said the government should offer funds to cattle farmers who report cases so that they have an incentive to test. Barring that, he said, reporting just adds reputational damage atop financial loss.

“These outbreaks have a significant economic impact,” Gingrich said. “Farmers lose about 20% of their milk production in an outbreak because animals quit eating, produce less milk, and some of that milk is abnormal and then can’t be sold.”

The government has made the H5N1 tests free for farmers, Gingrich added, but they haven’t budgeted money for veterinarians who must sample the cows, transport samples, and file paperwork. “Tests are the least expensive part,” he said.

If testing on farms remains elusive, evolutionary virologists can still learn a lot by analyzing genomic sequences from H5N1 viruses sampled from cattle. The differences between sequences tell a story about where and when the current outbreak began, the path it travels, and whether the viruses are acquiring mutations that pose a threat to people. Yet this vital research has been hampered by the USDA’s slow and incomplete posting of genetic data, Worobey said.

The government should also help poultry farmers prevent H5N1 outbreaks since those kill many birds and pose a constant threat of spillover, said Maurice Pitesky, an avian disease specialist at the University of California-Davis.

Waterfowl like ducks and geese are the usual sources of outbreaks on poultry farms, and researchers can detect their proximity using remote sensing and other technologies. By zeroing in on zones of potential spillover, farmers can target their attention. That can mean routine surveillance to detect early signs of infections in poultry, using water cannons to shoo away migrating flocks, relocating farm animals, or temporarily ushering them into barns. “We should be spending on prevention,” Pitesky said.

Q: OK it’s not a pandemic, but what could happen to people who get this year’s H5N1 bird flu?

No one really knows. Only one person in Texas has been diagnosed with the disease this year, in April. This person worked closely with dairy cows, and had a mild case with an eye infection. The CDC found out about them because of its surveillance process. Clinics are supposed to alert state health departments when they diagnose farmworkers with the flu, using tests that detect influenza viruses, broadly. State health departments then confirm the test, and if it’s positive, they send a person’s sample to a CDC laboratory, where it is checked for the H5N1 virus, specifically. “Thus far we have received 23,” Shah said. “All but one of those was negative.”

State health department officials are also monitoring around 150 people, he said, who have spent time around cattle. They’re checking in with these farmworkers via phone calls, text messages, or in-person visits to see if they develop symptoms. And if that happens, they’ll be tested.

Another way to assess farmworkers would be to check their blood for antibodies against the H5N1 bird flu virus; a positive result would indicate they might have been unknowingly infected. But Shah said health officials are not yet doing this work.

“The fact that we’re four months in and haven’t done this isn’t a good sign,” Worobey said. “I’m not super worried about a pandemic at the moment, but we should start acting like we don’t want it to happen.”

KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

Subscribe to KFF Health News’ free Morning Briefing.

A dozen people seated around folding tables clap heartily for a beaming woman: She’s donated two 13-gallon garbage bags full of clothes, including several Christmas sweaters and a couple of pantsuits, to a Presbyterian church.

A closet cleanout might not seem a significant accomplishment. But as the people in this Sunday-night class can attest, getting rid of stuff is agonizing for those with hoarding disorder.

People with the diagnosis accumulate an excessive volume of things such as household goods, craft supplies, even pets. In extreme cases, their homes become so crammed that moving between rooms is possible only via narrow pathways.

These unsafe conditions can also lead to strained relationships.

“I’ve had a few relatives and friends that have condemned me, and it doesn’t help,” said Bernadette, a Pennsylvania woman in her early 70s who has struggled with hoarding since retiring and no longer allows guests in her home.

People who hoard are often stigmatized as lazy or dirty. NPR, Spotlight PA, and KFF Health News agreed to use only the first names of people with hoarding disorder interviewed for this article because they fear personal and professional repercussions if their condition is made public.

As baby boomers age into the group most affected by hoarding disorder, the psychiatric condition is a growing public health concern. Effective treatments are scarce. And because hoarding can require expensive interventions that drain municipal resources, more funding and expertise is needed to support those with the diagnosis before the issue grows into a crisis.

For Bernadette, the 16-week course is helping her turn over a new leaf.

The program doubles as a support group and is provided through Fight the Blight. The Westmoreland County, Pennsylvania, organization started offering the course at a local Masonic temple after founder Matt Williams realized the area lacked hoarding-specific mental health services.

Fight the Blight uses a curriculum based on cognitive behavioral therapy to help participants build awareness of what fuels their hoarding. People learn to be more thoughtful about what they purchase and save, and they create strategies so that decluttering doesn’t become overwhelming.

Perhaps more importantly, attendees say they’ve formed a community knitted together through the shared experience of a psychiatric illness that comes with high rates of social isolation and depression.

“You get friendship,” said Sanford, a classmate of Bernadette’s.

After a lifetime of judgment, these friendships have become an integral part of the changes that might help participants eventually clear out the clutter.

Clutter Catches Up to Baby Boomers

Studies have estimated that hoarding disorder affects around 2.5% of the general population — a higher rate than schizophrenia.

The mental illness was previously considered a subtype of obsessive-compulsive disorder, but in 2013 it was given its own diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders, the DSM-5.

The biological and environmental factors that may drive hoarding are not well understood. Symptoms usually appear during the teenage years and tend to be more severe among older adults with the disorder. That’s partly because they have had more time to acquire things, said Kiara Timpano, a University of Miami psychology professor.

“All of a sudden you have to downsize this huge home with all the stuff and so it puts pressures on individuals,” she said. In Bernadette’s case, her clutter includes a collection of VHS tapes, and spices in her kitchen that she said date back to the Clinton administration.

But it’s more than just having decades to stockpile possessions; the urge to accumulate strengthens with age, according to Catherine Ayers, a psychiatry professor at the University of California-San Diego.

Researchers are working to discern why. Ayers and Timpano theorize that age-related cognitive changes — particularly in the frontal lobe, which regulates impulsivity and problem-solving — might exacerbate the disorder.

“It is the only mental health disorder, besides dementia, that increases in prevalence and severity with age,” Ayers said.

As the U.S. population ages, hoarding presents a growing public health concern: Some 1 in 5 U.S. residents are baby boomers, all of whom will be 65 or older by 2030.

This population shift will require the federal government to address hoarding disorder, among other age-related issues that it has not previously prioritized, according to a July report by the Democratic staff of the U.S. Senate Special Committee on Aging, chaired then by former Sen. Bob Casey (D-Pa.).

Health Hazards of Hoarding

Clutter creates physical risks. A cramped and disorderly home is especially dangerous for older adults because the risk of falling and breaking a bone increases with age. And having too many things in one space can be a fire hazard.

Last year, the National Fallen Firefighters Foundation wrote to the Senate committee’s leadership that “hoarding conditions are among the most dangerous conditions the fire service can encounter.” The group also said that cluttered homes delay emergency care and increase the likelihood of a first responder being injured on a call.

The Bucks County Board of Commissioners in Pennsylvania told Casey that hoarding-related mold and insects can spread to adjacent households, endangering the health of neighbors.

Due to these safety concerns, it might be tempting for a family member or public health agency to quickly empty someone’s home in one fell swoop.

That can backfire, Timpano said, as it fails to address people’s underlying issues and can be traumatic.

“It can really disrupt the trust and make it even less likely that the individual is willing to seek help in the future,” she said.

It’s more effective, Timpano said, to help people build internal motivation to change and help them identify goals to manage their hoarding.

For example, at the Fight the Blight class, a woman named Diane told the group she wanted a cleaner home so she could invite people over and not feel embarrassed.

Sanford said he is learning to keep his documents and record collection more organized.

Bernadette wants to declutter her bedroom so she can start sleeping in it again. Also, she’s glad she cleared enough space on the first floor for her cat to play.

“Because now he’s got all this room,” she said, “he goes after his tail like a crazy person.”

Ultimately, the home of someone with hoarding disorder might always be a bit cluttered, and that’s OK. The goal of treatment is to make the space healthy and safe, Timpano said, not to earn Marie Kondo’s approval.

Lack of Treatment Leaves Few Options

A 2020 study found that hoarding correlates with homelessness, and those with the disorder are more likely to be evicted.

Housing advocates argue that under the Fair Housing Act, tenants with the diagnosis are entitled to reasonable accommodation. This might include allowing someone time to declutter a home and seek therapy before forcing them to leave their home.

But as outlined in the Senate aging committee’s report, a lack of resources limits efforts to carry out these accommodations.

Hoarding is difficult to treat. In a 2018 study led by Ayers, the UCSD psychiatrist, researchers found that people coping with hoarding need to be highly motivated and often require substantial support to remain engaged with their therapy.

The challenge of sticking with a treatment plan is exacerbated by a shortage of clinicians with necessary expertise, said Janet Spinelli, the co-chair of Rhode Island’s hoarding task force.

Could Changes to Federal Policy Help?

Casey, the former Pennsylvania senator, advocated for more education and technical assistance for hoarding disorder.

In September, he called for the Substance Abuse and Mental Health Services Administration to develop training, assistance, and guidance for communities and clinicians. He also said the Centers for Medicare & Medicaid Services should explore ways to cover evidence-based treatments and services for hoarding.

This might include increased Medicare funding for mobile crisis services to go to people’s homes, which is one way to connect someone to therapy, Spinelli said.

Another strategy would involve allowing Medicaid and Medicare to reimburse community health workers who assist patients with light cleaning and organizing; research has found that many who hoard struggle with categorization tasks.

Williams, of Fight the Blight, agrees that in addition to more mental health support, taxpayer-funded services are needed to help people address their clutter.

When someone in the group reaches a point of wanting to declutter their home, Fight the Blight helps them start the process of cleaning, removing, and organizing.

The service is free to those earning less than 150% of the federal poverty level. People making above that threshold can pay for assistance on a sliding scale; the cost varies also depending on the size of a property and severity of the hoarding.

Also, Spinelli thinks Medicaid and Medicare should fund more peer-support specialists for hoarding disorder. These mental health workers draw on their own life experiences to help people with similar diagnoses. For example, peer counselors could lead classes like Fight the Blight’s.

Bernadette and Sanford say courses like the one they enrolled in should be available all over the U.S.

To those just starting to address their own hoarding, Sanford advises patience and persistence.

“Even if it’s a little job here, a little job there,” he said, “that all adds up.”

This article is from a partnership that includes Spotlight PA, NPR, and KFF Health News.

Spotlight PA is an independent, nonpartisan, and nonprofit newsroom producing investigative and public-service journalism that holds power to account and drives positive change in Pennsylvania. Sign up for its free newsletters.

KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

Subscribe to KFF Health News’ free Morning Briefing.

This article first appeared on KFF Health News and is republished here under a Creative Commons license.