Birds, Beasts and Workers: Avian Flu

Now that we’re done with COVID-19, it’s time to move on to the next pandemic.

Just kidding. We are, of course, not done with COVID. Over 1500 Americans died of COVID in April 2024. And our public health and worker health systems are still coping with (and hopefully learning from) the failures of the COVID pandemic.

Meanwhile, the country (and the world) are facing what may — or may not be the early stages of the next serious pandemic: Avian flu, also known as H5N1, is a disease caused by infection with avian influenza (or bird flu) virus. These viruses have generally spread among wild aquatic birds worldwide, including ducks, geese, swans, and storks, and have infected domesticated birds like chickens and turkeys.  Cows have also been infected with avian flu. And from cows, humans. The disease in cows is not fatal at this point.

And once again, workers are on the front lines. At this point, workers most at risk are those who work closely with infected animals: infected dairy cattle and domesticated birds.

Recently, one person who works with cows tested positive for avian flu. He had very mild symptoms. And  previous human case occurred in 2022 in Colorado. So far, there are no cases of avian flu being transmitted from person to person  — only animal to animal, or animal to person. Symptoms include coughing, fever, sore throat, muscle aches, shortness of breath or eye redness or irritation for 10 days after contact with an animal.

Worker Protection

Should we panic? In the short term, no.  From what we know now, there is no widespread transmission from animal to human, no transmission from human to human and the symptoms are mild for humans, unlike the deadly symptoms for birds. “Since 2022, 90 million domestic birds, mostly chickens and turkeys, have died or been intentionally killed across 48 states.”

And although virus particles have been detected in milk, pasteurization inactivates it.”  We don’t know if people can get avian influenza from drinking raw (unpasteurized) milk, but might be good to avoid it.

Of course, the key words here are “from what we know now.”

Bird flu has been detected in 49 dairy herds in nine states: Colorado, Idaho, Kansas, Michigan, New Mexico, North Carolina, South Dakota, Ohio and Texas. We know that almost all of the cattle outbreaks have been on large dairy farms. But this may just be the tip of the iceberg. 

Public health experts do not know when or if the H5N1 virus will evolve into a virus with more severe health effects that can be transmitted from person to person. In other words, we don’t know if — or when — avian flu will become a severe human pandemic.

The more this virus circulates, the more there is a chance for mutations,” said Dr. Jennifer Nuzzo, a professor of epidemiology who directs the Pandemic Center at the Brown University School of Public Health. And more mutations could mean a bigger risk of the virus becoming highly infectious among more people.

Bird flu has been detected in 49 dairy herds in nine states: Colorado, Idaho, Kansas, Michigan, New Mexico, North Carolina, South Dakota, Ohio and Texas. We know that almost all of the cattle outbreaks have been on large dairy farms. But this may just be the tip of the iceberg.  In recent weeks, studies have found genetic traces of H5N1 in a large percentage of commercial milk products. Significant amounts of viral material from the avian influenza have also turned up in wastewater in Texas.”

It raises a big and important question: How is it that so much virus is getting off of affected farms and into the national milk supply in the first place? The most plausible and also the most concerning scenario is that visibly sick cows, the ones with strange looking milk and flu-like malaise, are just the tip of the outbreak.

Although there’s little hard data at this point, scientists say the available evidence suggests that many more animals are likely being infected and producing virus-laced milk without any noticeable symptoms or changes to their milk’s color and consistency.

Experts think the virus could be transmitted from cows to humans through multiple paths, such as contact with milk, contaminated milking equipment, or possibly respiratory droplets.

But we don’t really know the extent of infection in the United States. Dairy cows are only required to be tested if they move across state lines, or they have symptoms and many infections are asymptomatic. And even if you find sick cows, it is impossible to determine an infection rate if all cows are not tested.

We also don’t know how many of the nation’s 100,000 dairy workers have been infected beyond the two that have been documented. But given that there is no widespread testing of workers, and the symptoms of infection are mild (which means it’s unlikely that many workers will go to a doctor or emergency room), we really have no idea how many dairy workers are infected. In fact, at this point, only a few dozen workers nation-wide even have been tested, although some farms and veterinarians report flu-like illnesses among farmworkers on dairy farms. All of that makes public health experts nervous.

That leaves the workers and their families vulnerable to a poorly tracked pathogen. And it poses broader public health risks. If the virus were to find its way into the wider population, experts say, dairy workers would be a likely route.

“We have no idea if this virus is going to evolve to become a pandemic strain, but we know today that farmworkers are being exposed, and we have good reasons to think that they are getting sick,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health.

Without testing, one useful way to determine the extent of the virus is through testing of wastewater. CDC launched the influenza A wastewater dashboard on its H5N1 monitoring page. Sequencing viruses from wastewater samples from 10 Texas cities have found H5N1 avian flu virus in 9 of them — sometimes at levels that rivaled seasonal flu.

CDC Issues Worker Protection Guidelines

To protect workers, the Centers for Disease Control and prevention has issued guidance (along with a chart that can be posted) to protect workers who may be exposed to infected animals. The guidelines urge employees to avoid contact with sick birds, livestock, or other animals, carcasses of these animals, raw milk, feces or litter, and water on farms with potentially infected animals or waste.  These would include Poultry and livestock farmers and workers, slaughterhouse workers backyard bird flock owners, veterinarians and veterinary staff, animal health responders and public health responders.

If contact with animals or their wastes cannot be avoided, workers should use personal protective equipment, including gloves, boots, waterproof coveralls and aprons, as well as NIOSH-approved N95 respirators. The guidance also includes instructions for putting on and taking off the equipment.  When workers wear respirators, employers must comply with OSHA’s respiratory protection standard which requires workers to be trained, medically-cleared, and fit-tested for respirator use.

Some of these recommendations sound better on paper than in reality. Disposable N-95 masks are likely to become soggy very quickly in dairy milking areas, necessitating the use of more expensive, but reusable elastomeric half mask respirators.  And wearing protective equipment all day is not only uncomfortable, but also presents potentially deadly heat hazards.

CDC has also asked state health departments to work with their state agriculture department counterparts and partners in communities, such as farmworker organizations, that can help coordinate and facilitate PPE distributions.

Most dairy workers are immigrants — especially on the huge dairy farms where all of the infected cattle have been found. They usually speaking Spanish, but other languages as well. Many are undocumented and therefore unlikely to go to hospitals. Most also have no health insurance or sick leave.

All of this leaves something to be desired from a public health standpoint.

First, most dairy workers are immigrants — especially on the huge dairy farms where all of the infected cattle have been found. They usually speaking Spanish, but other languages as well. Many are undocumented and therefore unlikely to go to hospitals. Most also have no health insurance or sick leave and would be reluctant to lose pay to go see a doctor for mild symptoms. And their employers are unlikely to be happy about word getting out that their workers — or their herds – are infected.

Their lives are hard, with little access to medical treatment.

Farmworkers often wake at 5 a.m. to prune cherry branches, pluck strawberries or milk cows, Nerio said of the patients she typically sees through her work with InterCare Community Health Network, headquartered in Bangor, Michigan.

Sixteen-hour work days are common. By 9 p.m., many workers return from farms to modest camps where entire families may crowd into a single room and share bathrooms. They chase the growing seasons in Michigan, Florida, Texas and beyond, keeping enough of their earnings to pay for food, rent and fuel while sending the rest of their money home. Homemade remedies, like cinnamon tea, along with ibuprofen and Vicks VapoRub amount to health care for many workers when they feel unwell.

And many farm workers have little faith that their employers are adequately concerned about their health.

The owners of such farms “don’t care about our health, they just care that we do our jobs,” said Luis Jimenez, who works on a dairy in upstate New York and founded a group supporting undocumented immigrant farmworkers.

“Their cows’ health is more important to them than their workers,” he added.

Farms are often geographically remote, and the workers — who sometimes live on site — may not have transportation to reach medical care. And to many, the kinds of symptoms ascribed to bird flu infection may not seem particularly urgent.

“We’re talking about an eye infection or a cough, and these are people who have back aches and arm aches and broken this and that,” said Monica Schoch-Spana, a medical anthropologist at the Johns Hopkins Center for Health Security.

Splintered Public Health System

Another major problem is the country’s splintered public health system. Several federal agencies have some authority over different parts of dairy farms and farmworkers, although they claim to be working closely together on the problem:

The Centers for Disease Control and Prevention (CDC) can provide guidance for protecting farm workers and others, and conduct epidemiological investigations to determine how and where the virus is spreading. But CDC guidance is just that: guidance — with no ability to enforce it. And CDC must be invited onto farms to conduct epidemiological studies. Farmers — who are already dealing with high costs and low milk prices — are reluctant to have federal agencies look at their farms because they fear losing money if their herds are infected.

The Occupational Safety and Health Administration (OSHA) covers workplace safety and the agency has the authority to enforce safe working conditions. But OSHA has no infectious disease standard (aside from bloodborne pathogens), and the agency is forbidden from setting foot on any farm with ten or fewer workers (unless the farm also has a “temporary labor camp.”)  OSHA can use its General Duty Clause to enforce safe working conditions, but there are significant legal hurdles that the agency must overcome to use it. In addition, the agency is significantly underfunded. OSHA’s Avian Flu webpage is here.

The US Department of Agriculture (USDA) regulates large commercial farms. USDA can mandate testing of animals, but not of farmworkers. So far, USDA has mandated testing of lactating cows only when they are about to move to another state, and reporting of any cow that tests positive.

The Food and Drug Administration (FDA) is responsible for the safety of the food supply. Although signs of the virus have been found in milk, the FDA has determined that pasteurization inactivates the virus.

Industry Opposition

Dairy farm owners and some states are resisting federal initiatives. CDC, for example, needs to be invited to go onto farms to conduct epidemiological field studies. Some states, like Texas don’t trust the feds, and some farmers are reluctant to let CDC onto their farms for fear of losing money if infected cows (or workers) are identified. The FDA is requiring that all milk from infected cows be discarded.

“It’s overreach. They don’t need to do that. They need to back off,” Texas Agriculture Commissioner Sid Miller, a former rodeo cowboy who is a possible pick to lead the USDA if former President Donald Trump wins the presidential election, said in an interview.

To partially address farm owner resistance, the Biden administration announced last week that it would compensate dairy farmers for cooperating with its efforts to limit the spread of the avian flu virus.

Under the so-called indemnity program, farms would receive up to $28,000 to protect workers and cover costs incurred treating and testing sick cows. Producers may also receive payments for lost milk production on farms with confirmed bird flu cases.

Farm workers who agree to participate in government-led studies will also be compensated for their time.

What is to be done?

Outreach to farm workers

• Worker Outreach: There is much more that can be done to reach farm workers. It may be difficult for public health and worker advocates to reach workers on farms, but health officials can still support migrant workers in other settings. “They go to church, they go to stores, they go to restaurants, and there are other ways to reach them,” said Amy Liebman, a program officer at the Migrant Clinicians Network.