(InvestigateWest) -- On a recent Monday morning, workers began their week on a large poultry farm in Franklin County, Washington, home to over 800,000 chickens.
By the end of the day, avian flu had been discovered among some of those chickens. By the end of the week, four workers came down with the illness, which had infected only a handful of other people in the U.S. And after two more days of testing by the Benton Franklin Health District, another 10 workers at the farm tested positive.
That outbreak, initially detected Oct. 14, represented the first human cases this year of the avian flu in the Pacific Northwest. The first human case in Oregon was confirmed Nov. 15, adding to mounting evidence that the flu is spreading to farmworker populations across the Western U.S. But efforts to test and monitor the disease among workers are spotty and inconsistent and leave the responsibility for getting tested on the laborers themselves, many of whom are undocumented and can't afford to take time off if they test positive.
Meanwhile, the virus is spreading rapidly among cows and chickens, raising concerns among epidemiologists that the avian flu could merge with the regular flu and cause a pandemic, making it even more urgent to try to limit the spread among people.
Regular testing helps health officials better understand how the virus is being transmitted and how to protect workers. Without it, dozens of positive workers could be undetected, leaving them to handle symptoms on their own.
"The gold standard for public health is to be able to respond, to do surveillance and to understand what's happening," said Amy Liebman, chief program officer of workers, environment and climate for Migrant Clinicians Network, a nonprofit organization made up of health care workers who provide care to underserved communities. "If we don't know that these things are happening, it's very hard to respond."
In Idaho, which has recorded the most cases among livestock of any state in the region, only seven human tests have been conducted, and officials are not gathering information about workers on farms with animal outbreaks. By contrast, Washington has tested 77 people -- all of whom were associated with the Franklin County farm -- and Oregon has tested 33, and both states are gathering information about exposed workers.
Washington and Oregon are two of six states where humans have tested positive for the avian flu, but infectious disease researchers suspect there are far more unreported cases because of a lack of testing by state and local health districts.
"The ratios of how many herds and flocks have tested positive versus how many people have been tested, that stresses me out in every state," said Elizabeth Strater, spokesperson for United Farm Workers, who is based in Los Angeles and previously worked on farmworker union efforts in Washington and Oregon.
Avian flu has infected wild birds, chickens and cattle in states across the U.S. Since March, Idaho has reported 35 positive cases of avian flu in cattle and 41 in poultry, Washington has 52 cases among poultry, and Oregon has 41 among poultry. There is no known human-to-human spread so far, which keeps the public health risk low, but if transmission between humans happened, scientists worry it could grow into a dangerous pandemic.
The CDC recommends that all persons exposed to avian influenza virus from infected birds, cattle or other animals be monitored for symptoms of infection and tested if they had close contact with a positive case, starting the first day they were exposed and continuing until 10 days after the last exposure. In early November, the agency called for increased testing by states to fight the spread of the virus.
None of the three Northwestern states require testing of people exposed to animals with avian flu. In Idaho, health districts are waiting for a human case before even beginning to gather information about exposed workers. In Oregon, health districts offer testing, but they don't require it and only offer tests to people who work with a sick animal without personal protective equipment.
Mike Lang, spokesperson for the Washington State Department of Health, said the state "will evaluate each opportunity to test people as it comes."
Amy Dillon, spokesperson for South Central Public Health District which encompasses Cassia County, where Idaho's first outbreak of avian flu was found in cows, said the health district is focusing on distributing personal protective equipment to dairy farms rather than testing.
"We are not getting line lists relating to potential avian flu exposure, because there have been no human cases in the state of Idaho at this time," Dillon said.
But farmworker advocates and public health experts say there is a vast undercount of human avian flu cases and testing more workers who don't have symptoms would help address the undercount and help detect positive cases to prevent the continued spread.
Past protocols in cases of a transmissible illness outbreak include contact tracing, which is when a health district gathers a list of people who were exposed and their contact information, age, location and symptoms so that they can screen them for the illness.
But public health districts in Idaho are not doing such contact tracing yet.
In an email, AJ McWhorter, public information officer for the Idaho Department of Health and Welfare, said just three people were tested by a local public health district in June. The other four tests were completed by private clinics or hospitals. Only one person was tested in the last two months, despite the U.S. Department of Agriculture report of two new cases among cattle in commercial dairies in the last 30 days.
In Idaho, it is up to the individual employers to encourage workers to be tested. Rick Naerebout, executive director of the Idaho Dairymen's Association, said the association and health districts have ensured that dairies with positive avian flu cases in their cattle have information about the flu and where to test, but it is up to them to go get tested.
"You've got a workforce (in dairies) that doesn't always have legal status, so there's going to be reservations about going and getting tested at a health district, or any sort of medical service," Naerebout said.
Liebman, who works with undocumented farmworkers in her role at the Migrant Clinician Network, said there are always risks for undocumented migrants in the U.S., but they do not need to provide their immigration status to obtain a flu shot or health care of any kind.
Dillon said if there was a human case in Idaho, the health district may decide to do contact tracing for exposed people, on a case-by-case basis.
Idaho's dairy industry employs over 33,000 workers and is ranked third in the U.S. for milk production. Around 90% of Idaho dairy workers are migrant workers, and many of them are undocumented.
In the Franklin County, Washington, outbreak, Heather Hill, a public health nurse and deputy director of the Benton Franklin Health District, said district staff spoke with the poultry farm owners, who reported workers with pink eye, which is a symptom of the avian flu virus. The district then tested workers at two clinics it hosted at the farm.
After the clinics, Hill said the district got a list and contact information for all the potential employees who were exposed. The district also offered standard flu vaccines.
Ten new cases among animals were reported in Snohomish County in early November, according to the U.S. Department of Agriculture. But no new workers were tested by the Washington Department of Health.
Liebman said surveillance is one of the few ways public health agencies can understand how people are getting exposed to the illness. Surveillance refers to having public health staff regularly contact local private health care providers and workers to get information about whether they're seeing symptoms of the flu.
"You want to try to understand and do a case report on exposure," Liebman said. "You try to ask someone who is testing positive questions like 'Who were you in contact with? What were you in contact with? Did the farm already have a positive test or positive herd? Were you working with sick animals? Were you not around animals at all, and what were your tasks that you were doing? Are you a milker? Are you a pusher? Are you dealing with calves?' When you understand the tasks and what kind of PPE they were wearing, you begin to understand the exposure."
Strater told InvestigateWest that she hasn't heard of any states doing surveillance. Instead, she said, they are doing more passive monitoring, by relying on employers to report workers who show symptoms of avian flu.
"Some employers will, some won't," she said.
Clinicians cite Colorado as a state that has effectively responded to outbreaks of avian flu by testing workers. The state has tested 137 people who were exposed, according to the Colorado of Public Health and Environment. Public health workers in Colorado and Michigan also tested blood samples of over 100 workers who were known to have been working with infected cows and found 7% had avian flu antibodies, meaning they had unknowingly contracted the virus.
But Liebman said that even workers who were exposed to positive animals but not showing symptoms should be tested.
By testing all exposed workers, Liebman said, local health authorities would have "a much better understanding of transmission, of what protects the worker and the likelihood of workers actually even having it while being asymptomatic."
When asked why they weren't testing more workers, Dillion said that workers in Idaho were given equipment to protect themselves while working and feels that is sufficient enough not to warrant testing people without symptoms.
Jonathan Modie, spokesperson for the Oregon Health Authority, said they reserve testing for people with symptoms or asymptomatic people who had a high-risk exposure, meaning a breach or misuse of PPE. Lang said the Washington Department of Health is clarifying the new CDC guidelines before it implements more testing.
So far, human cases of avian flu have been mild. Dr. Jürgen Richt, a professor and director of the Center of Excellence for Emerging and Zoonotic Animal Diseases at Kansas State University, told InvestigateWest that so far people who have tested positive for avian flu have had mild respiratory symptoms and conjunctivitis, or pink eye.
But that wasn't always the case. In 2003, when avian flu reemerged after the first outbreak in 1996, Richt said there was transmission of the flu to humans and there was a high fatality rate.
According to Yale Medicine, the mortality rate was 50% for the 900 people who were infected with the bird flu from 2003 to present.
"We were lucky that the virus got milder over time in humans," Richt said.
Even with mild symptoms, Liebman said people who are positive for avian flu are recommended Tamiflu to treat the illness and to try to minimize the spread.
Avian flu has destroyed many backyard poultry operations in the Pacific Northwest and cost commercial farmers dairy milk and their flocks and eggs.
Amber Betts, spokesperson for the Washington Department of Agriculture, said in poultry, early signs of an avian flu outbreak include chickens becoming lethargic and confused. In dairy operations, an early sign is a significant drop in milk production.
Once a veterinarian and lab receive positive tests results for avian flu, the farm has to stop operations and sanitize. For backyard farms, Betts said there is a fallow period, where no animals can live on the backyard farm for at least 120 days. But that period is shorter for commercial farms because there are heavy disinfection and testing procedures that a farmer must do before they can begin farming again.
If a farm does have a positive case of the flu, a farmer must report it, Betts said. The Department of Agriculture gives farmers indemnity payments for eggs and chickens that they had to euthanize for being exposed to the flu.
There are no payments to a farm owner if any of their workers contract avian flu and must take time away from work. That is what worries Strater, who says it is a gamble to rely on the farm owner and workers to test themselves or report positive cases.
"The issue is the employers because both the employers and the workers have a financial incentive to avoid testing," she said.
All recorded cases of avian flu in humans, except for one, came from farmworkers who worked with infected animals.
"Really what we've seen in humans is when the humans are working with an infected animal," Betts said. "That could be while they are helping clean up after an outbreak in a farm and maybe biosecurity protocols aren't to the highest standards. Maybe somebody accidentally rubs their eye or that kind of thing."
Humans can get the virus from animals by touching an infected animal's bodily fluids, including animal milk, and from touching a surface that was contaminated with the virus and then touching their eyes or mouth. People who have worked with infected animals are considered a "high risk exposure," according to the CDC, and it recommends they be tested for the virus by local health districts.
Some scientists worry about the avian flu mixing with the seasonal flu in pigs, where an avian flu case was found in one in Oregon. Pigs are susceptible to both animal and human viruses. Scientists say a mixing of the two viruses could increase the risk of a flu pandemic.
Liebman thinks the public health response to avian flu should be informed by what people learned from the COVID-19 pandemic, which ravaged agricultural and meat packing plants where workers were not being tested for the highly transmissible virus.
Advocates for workers then, and now, say workers can't afford to have a positive test. They don't get paid sick time off work if they have to quarantine for two weeks.
Unlike many of the severe symptoms of COVID-19, people who are positive for avian flu have experienced mild symptoms that they could hide if they want to continue working.
The hesitancy is why Liebman says it is important for health departments to deploy community health workers who speak Spanish, who come from similar backgrounds as the workers and who can understand their hesitancy to report an exposure or illness.
"You have to understand that the risk that a worker takes simply to be in this country to work is really significant, and their priority is to stay employed and work," she said. "There's a lot of fear around potentially losing their job. They don't want to make their employer upset. They don't want to miss any work. There's fear of just losing money if they do test positive."