If you weren’t aware yet, a bird flu outbreak is currently raging through cattle and poultry farms across the country. At a time when President Trump has halted all CDC communications, and noise around reform of our public health grows strong, we are inadvertently creating ideal conditions for a next pandemic. And who is overlooked? The common man that works our fields, cleans milking equipment, and culls flocks when the time has come. Perhaps we should reconsider our reliance on government disease surveillance systems.

H5N1, a particularly bad variant of the bird flu also known as highly pathogenic avian influenza “HPAI”, has a mortality rate exceeding 90% in birds. The US now unexpectedly has cattle as a viral host. For decades, epidemiologists have kept a close watch on H5N1, listing it as having human pandemic potential.

An overview of the US bird flu situation

The situation is alarming. While you might have heard stories of smaller chicken farms dealing with infections, the problem is much bigger than that. In early January 3 million chickens needed to be disposed of at a single North Carolina farm. This barely made headlines. More than 33 million cumulatively have been infected over the last 2 months alone, the majority of them culled and disposed of, often by digging trenches and ‘composting’ the waste. To put this into perspective, that is 9,764 forty-foot shipping containers filled with carcasses, the equivalent of filling 1.7 trans atlantic container ships with dead animals.

The currently circulating H5N1 strain (clade 2.3.4.4b H5N1) is showing unprecedented levels of transmission to mammals, and a broadened host range, raising concerns about its spillover into humans. In fact, there is evidence that the California poultry infections largely originate from infected cattle, and not from the wild birds. The cattle bird flu epidemic has been declared an emergency in California, and has been steadily getting worse since early 2024. As a consequence, the USDA has restricted interstate cattle transport in April 2024, requiring clearance through testing. A National Milk Testing order is in place since December, now active in 36 states, mandating dairy farms to submit milk samples for testing.

Geographic Distribution of cummulative Avian Flu Cases in commercial and backyard birds, Dec 2024 - Jan 2025. Interactive visualization using Python, Plotly.js, by @kenzasam, code: GitHub, data source: USDA

And of course, people (mostly farm workers) have been infected with the H5N1 bird flu strain. Yet, it has surprisingly been less deadly in humans compared to previous outbreaks (50% mortality in humans). Currently 68 detected human cases have been confirmed and a first human fatality took place on January 5, 2024, in Texas. The CDC has integrated screening for H5N1 in the national flu surveillance system, which tracks Flu variants primarily through hospitalized flu patients. Minnesota also took matters in their own hands and started mandatory testing for H5N1 for hospitalized Flu patients.

Yet these measures are not nearly enough to contain the spread of H5N1 and prevent disastrous effects. We know that. And still we are not doing better. Why?

An ideal One Health approach

Testing remains our most effective tool to prevent a pandemic. If we want to detect human-to-human transmission as soon as it occurs, we have to understand the spread of this virus from host to human. Human-to human transmission is what could trigger a deadly pandemic. Ideally, testing would be readily accessible to anyone in direct contact with any animals at risk of avian flu through both rapid testing in the form of a lateral flow assay for farm workers, comprehensive animal testing testing programs, and continued surveillance. Expanding testing capacity is surprisingly cost-effective. During the COVID-19 pandemic, large scale testing likely saved upwards of 1 to 4 million lives and averted 7 million hospitalisations in the US. Another critical countermeasure involves vaccinating animal workers against the seasonal flu. A co-infection of seasonal flu and H5N1 can lead to an exchange in genetic material between the strains, possibly leading to a pandemic strain. And of course, improvements in farm biosecurity and animal vaccination programs are equally important.

But, this is not how we are handling the current situation. Our current testing infrastructure focuses predominantly on dairy cattle - driven by the convenience of milk sampling- , and existing Influenza surveillance. This creates a massive blind spot in our epidemiological understanding. The US hosts approximately 30 million beef cattle, yet we have virtually no systematic surveillance of this population. The biological dynamics of H5N1 in mammals remain poorly understood - we’re essentially flying blind with a pathogen that has already demonstrated concerning adaptability. With H5N1 being less deadly in cattle than poultry, farmers have a hard time identifying the disease from symptoms. The US completely failed at preventing the spread of the virus within cattle, and the effects on farmers and vets (and soon probably your milk and beef prices) is measurable (see here). Similarly, there is no surveillance system in place for animal workers. Only those who self-report illness are further investigated. We can only extrapolate from known animal numbers, how many humans have been exposed. Why are we making these mistakes, while being fully aware of better approaches? Managing the H5N1 outbreak problem is not just a public health issue, but a political and socio-economic crisis.

Even if farm owners want to implement comprehensive testing programs, the reality of agricultural labor demographics creates significant barriers. Nearly 48% of agricultural workers are immigrants, many Spanish-speaking, facing significant barriers to accessing health information and care. Many workers lack health insurance or documentation status, making them hesitant to engage with the healthcare system. And yet, it is these people that perform the grueling task of culling infected animals, often without adequate protection.

Ag vs Gov

The threat of spillover however increases with how worker conditions are managed. Numerous reports detail alarming worker conditions, yet we remain collectively blind to this crisis. PBS reports (quote) in Colorado two poultry operations employed about 650 temporary workers — Spanish-speaking immigrants as young as 15 — to cull flocks. Inside hot barns, they caught infected birds, gassed them with carbon dioxide, and disposed of the carcasses. Many did the hazardous job without goggles, face masks, and gloves. By the time Colorado’s health department asked if workers felt sick, five women and four men had been infected. They all had red, swollen eyes — conjunctivitis — and several had such symptoms as fevers, body aches, and nausea.

Farmers hesitate to report cases, knowing that detecting avian flu risk financial devastation. With profit margins already razor-thin in industrial agriculture, many farmers simply cannot afford transparency. So it is even more surprising to learn that participation in the USDA financial assistance program for testing and biosecurity remains very low. Less than 2% of eligible farms (580 herds across 15 States) are currently enrolled in USDA’s HPAI financial support programs for dairy cattle producers. The USDA’s financial assistance program for dairy farmers, while well-intentioned, illustrates the disconnect between policy and reality. The application process requires extensive documentation, financial records, and often English language proficiency - barriers that effectively exclude many smaller operations and immigrant-owned farms.

As far as I see it, the CDC and USDA are doing their best with the tools they have (minimal financial help, testing hospitalized people and farm workers who present sick). But we have to admit these tools are not functional in the scenario we are dealing with now. An awareness campaign is not going to work if we are dealing with more systemic, societal issues.

“Producer refuses to send workers to Sunrise clinic to get tested since they’re too busy. He has pinkeye, too,”

Said an email from the Weld, Colorado, health department, according to KFF Health.

“We know of 386 persons exposed — but we know this is far from the total,”

said an email from a public health specialist to officials at Tulare’s health department recounting a call with state health officials, according to KFF Health.

With COVID-19, we were a front against a “foreign invader”, a virus originating from abroad, a virus that affected all citizens equally (almost). Now, we are fighting a virus that is attacking the most vulnerable of our society first. Workers are hesitant to get tested due to cost, with employers not wanting to run H5N1 testing through worker’s compensation. And there aren’t many incentives to do so. We have to face the situation we created. A One Health approach will simply not work in the America we are today. When the US becomes ground zero for an H5N1 flu pandemic, we will have confront this.

This post is still a work in progress. I will continue to add references. I continuously add H5N1 ressources for the community to www.usbirdflu.com