In recent months, the avian influenza virus, commonly known as bird flu, has taken alarming steps toward becoming a bigger threat. The highly pathogenic H5N1 strain has now been detected in dairy cows, marking an unexpected and troubling leap.
“It’s endemic in cows now. There is no way this is going to get contained on its own,” said Seema Lakdawala, an influenza virologist and co-director of the Center for Transmission of Airborne Pathogens at Emory School of Medicine, for The Guardian.
If it’s endemic in cows, that means the virus has established a continuous presence in cattle populations, spreading persistently rather than being a temporary outbreak. In other words, the virus is spreading from cow to cow, making containment even more difficult. A recent study has also found that dairy workers probably spread the virus to their indoor cats after the cats consumed raw milk from infected cows.
All of this suggests the virus has adapted to infect mammals more efficiently. Are humans next?
Farms Were Scrambling to Contain It — Now They’re Desperate
H5N1 initially spread from wild birds to poultry, devastating the U.S. poultry industry. Millions of birds have been culled to contain outbreaks, leading to egg shortages and soaring prices. Despite these efforts, the virus has infected over 138 million birds across the U.S. and Puerto Rico — likely an underestimate.
In birds, H5N1 is often fatal, causing respiratory distress, swelling, lack of coordination, and sudden death, wiping out entire flocks within days. In cows, the virus appears less severe, with symptoms such as reduced milk production and lethargy. However, the fact that it has jumped to cattle — an unusual host — suggests H5N1 is evolving new ways to spread.
To make matters even worse, the Trump administration has scaled back funding for global disease surveillance programs and disbanded key health security teams. It even “accidentally” fired teams working specifically on the avian flu and was reportedly trying to rehire them afterward.
In terms of animal lives lost and resources, this is already a tragedy. But if the virus becomes endemic in humans, things can get much worse, fast.
The Virus Is Already Moving to Humans
On April 2, 2024, a dairy worker in Texas came down sick. He was infected with the avian flu that was most likely spreading from cow to cow. The cow-to-cow spread became evident as cow herds in five different states became ill. Fast forward to October 2024 and California had reported that 133 of its 1,100 dairy herds were infected, with a bovine mortality rate of around 15%. Fast forward once more to February 2025, and 70 people have been confirmed infected, whether from birds or cows.
The risk of the virus mutating and becoming able to spread for humans to humans is low. But the more it goes unchecked, the more likely it is for that dangerous mutation to happen. If this is the way things turn out, we may end up with another pandemic on our hands.
Bird flu is also spreading in the background of the worst (human) flu season in 15 years. As health systems are under pressure and all sorts of flu variants are flying around, the risk of a dangerous reassortment becomes all the more likely.
A Concerning Backdrop
In light of all these events, the Trump administration has curtailed public health communications. This suspension has delayed the dissemination of critical information regarding the spread of avian flu among various species, including dairy cows and domestic cats, and its potential transmission to humans. Additionally, the administration has undertaken significant staffing reductions within key federal agencies responsible for disease surveillance and response.
The U.S. Department of Agriculture (USDA) experienced layoffs affecting 25% of the staff in its National Animal Health Laboratory Network program office, a central entity coordinating efforts to track and control animal diseases. The administration has also ordered officials to stop communicating with the World Health Organization, adding another obstacle in the face of transparency and scientific collaboration.
As for what the administration actually intends to do to tackle this ongoing outbreak, things are extremely vague. Kevin Hassett, director of the national economic council, told CBS’s Face the Nation they will use “biosecurity and medication” to “have a better, smarter perimeter”. What that actually means is hard to assess.
Meanwhile, the virus is now entrenched in cows, making the risk of a worst-case scenario — a mutation that enables sustained human-to-human transmission — more pressing than ever. The last pandemic showed us the cost of ignoring early warning signs, and yet history seems to be repeating itself. Whether or not the bird flu becomes the next pandemic may depend less on science and more on the political will to act before it’s too late.
