Even as it has become increasingly clear that the avian flu outbreak on domestic farms began months earlier — and is likely much more widespread — than previously thought, federal authorities have stressed that the virus poses little risk to humans. humans.
Yet there is a group of people at high risk of infection: the approximately 100,000 men and women who work on those farms. There has been no widespread testing to see how many might be infected. No one has been vaccinated against avian influenza.
This leaves workers and their families vulnerable to a poorly monitored pathogen. And it poses broader public health risks. If the virus were to spread into the broader population, experts say, dairy workers would be a likely route.
“We have no idea whether this virus will evolve into a pandemic strain, but today we know that agricultural workers are exposed and we have good reason to think they are getting sick,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health.
The majority of dairy farm workers are Spanish-speaking immigrants, often undocumented, who may not have paid sick leave or are not protected by workplace safety laws. They may not have access to healthcare workers and their employers may be intolerant of absences.
“This sector of workers is not only exposed to the highest risk because they have direct and intimate contact with secretions, raw milk and infected animals, but is also exposed to the highest level of risk in terms of the absence of a network of Social Security,” said Elizabeth Strater, an organizer with United Farm Workers.
Interviews conducted with more than three dozen federal and state officials, public health experts, farmers and worker organizations show how little is known about what is happening on farms: how many workers could be affected, how the virus is evolving and how it is spreading among cows.
So far the virus, called H5N1, has been detected in cattle herds in nine states. Although veterinarians said there are unconfirmed reports of farm workers with flu-like symptoms, only 30 were tested on Wednesday.
Barring extraordinary circumstances, state and federal health officials do not have the authority to require access to farms. Instead, the Food and Drug Administration and the Department of Agriculture are testing the virus on milk and ground beef on supermarket shelves.
The Centers for Disease Control and Prevention is waiting for infected people to show up at clinics.
“Do you want to find out if a virus is spreading so much among people that it's coming to the emergency room en masse, or do you want to catch it on farms so you can treat people and slow the spread?” said Rick Bright, CEO of Bright Global Health, which focuses on responses to public health emergencies.
An intricate regulatory system complicates the situation, said Dr. Jay Varma, who served in the CDC's foodborne illness branch and oversaw food safety as deputy commissioner at the New York City Health Department.
The Agriculture Department regulates large commercial farms and can mandate testing on animals – although it has not yet done so – but not on farm workers. The department “never wants to be in the position of having to declare that the food supply from the United States is unsafe, because some of these food products could be exported to other countries and that can have a huge economic impact,” Dr. . .Varma said.
The CDC has authority over ports of entry into the United States, but domestically the agency needs state approval to do much of its work. The FDA, the Occupational Safety and Health Administration, the Environmental Protection Agency, and Citizenship and Immigration Services all have a role to play, but each has its own layers of bureaucracy and institutional culture .
This patchwork can pose an obstacle during an epidemic, some experts have said. In 2009, the response to an outbreak of bacterial infections in a deli meat was delayed because the Department of Agriculture regulated the meat, the FDA was responsible for crushed black pepper covering it, and the CDC was tasked with investigating people who had become ill .
Dr. Nirav Shah, principal deputy director of the CDC, dismissed the idea that bureaucracy was a barrier as “overly simplistic” and said agencies responding to the outbreak spoke numerous times a day to coordinate their activities and work with state partners.
“This stuff is hard,” he said. But “we are working together on this because we have common goals.”
Because of the relatively small number of cases – 36 affected farms out of about 26,000 nationwide and one infected farm worker – some farmers see bird flu as a distant threat. Even those who support public health efforts are hesitant to let federal officials onto their properties.
Jason Schmidt owns Grazing Plains Farm in Whitewater, Kan., “a little farm” as he calls it, with 70 dairy cows that he raises himself. Mr. Schmidt said he supports the government's role in public health matters, but he wouldn't want officials hanging around his farm.
If he saw a sick cow, “I would definitely hope to report it,” he said. “But there's that little devil on my shoulder saying, 'Shut up and divert that milk from those sick cows and put it down the drain and don't say anything.'”
Mitch Breunig, owner of Mystic Valley Dairy in Sauk City, Wisconsin, said that if his veterinarian had determined it was “prudent,” he would have tested a cow with bird flu symptoms, but “I really don't want the CDC coming to my farm.”
So far, the outbreak has hit not small farms, but giant dairies that increasingly dominate the sector and often rely on migrant workers.
The owners of these farms “don't care about our health, they just care about us doing our jobs,” said Luis Jimenez, who works on a dairy farm in upstate New York and founded a group that supports deprived immigrant farm workers. of documents.
“For them, the health of their cows is more important than that of their workers,” he added.
Farms are often geographically remote and workers, who sometimes live on-site, may not have transportation to get to medical care. And to many, the types of symptoms attributed to avian flu infection may not seem particularly urgent.
“We're talking about an eye infection or a cough, and these are people who have back pain and arm pain and have broken this and that,” said Monica Schoch-Spana, a medical anthropologist at the Johns Hopkins Center for Health Security.
Even without access to farms, health officials could support migrant workers in other settings, advocates noted. “They go to church, they go to stores, they go to restaurants, and there are other ways to reach them,” said Amy Liebman, program manager at the Migrant Clinicians Network.
To make testing more attractive, community centers could offer other health services, legal assistance and food, and educate workers on how to protect themselves and their families, Liebman said.
Dr. Shah said the CDC is working with veterinarians and organizations like the Migrant Clinicians Network to reach agricultural workers. “We would also like to offer testing to more workers,” he said.
On Monday, Dr. Shah asked state health officials to provide goggles, face shields and gloves to farm workers and to partner with trusted community organizations to educate them about the importance of the equipment in preventing infections.
Despite the health risks, agricultural workers are not required to wear protective equipment. “It's not a mandate, no one is forced to do anything here,” Dr. Shah said.
But the nature of farm work and the environments in which it is done, such as milk parlors that quickly make masks wet and unusable, can make wearing protective gear difficult.
Some states have taken measures to contain the outbreak, with limited success.
Texas offered to provide protective equipment to dairies, but only four stepped forward, according to a spokesperson for the state health department. Idaho has also offered protective equipment since the outbreak began, but no farms have taken up the offer.
Idaho health officials did not ask to go to the farms “for privacy and biosecurity reasons,” Dr. Christine Hahn, the state epidemiologist, said in an email, although they helped test a worker for infection agricultural.
Michigan bans the display of dairy cows and poultry until the outbreak subsides. The state does not require testing of cows or farm workers.
The current situation has shown that dairy farms can cause new outbreaks that spread quickly, as has long been the case on poultry and pig farms, several experts said.
“If I were to hide the emergence of a new virus in the United States, one of the best places to hide it would be among animal workers in rural America,” said Dr. Gregory Gray, an infectious disease epidemiologist at the University of Texas Medical Branch. .
Surveillance of these workers “is not as strong as we might see for other population groups,” he said.
To build surveillance networks that include farm workers and their families, federal, state and local agencies will first need to establish trust, said Dr. Andrew Bowman, a veterinary epidemiologist at The Ohio State University.
“If you look at the influenza surveillance we've done in pigs, this didn't happen overnight,” Dr. Bowman said. “It took ten years to build.”
While surveillance is important, some experts caution against testing farm workers without first addressing their needs.
“If we set out to collect information that will only benefit others and not necessarily protect them directly, I just think that's a very difficult thing to do ethically,” Dr. Nuzzo said.
Michael Salazar contributed to the reporting.