If you were to ask a dairy farmer about the biggest threats to their business, you might expect them to mention fluctuating milk prices, changing weather patterns, or even labour shortages. What you probably wouldn’t hear is this: Bird flu.

H5N1 (the virus responsible for avian influenza) isn’t just a problem for poultry farms anymore. It has found its way into dairy cattle. In the United States alone, the virus has been detected in cows across 16 states. Meanwhile in India, concerns about its potential spread through dairy products are mounting.

Bird flu isn’t new. It has been circulating in birds for decades. But what makes the current outbreak so concerning is its expanding reach. In India, H5N1 cases have been rising, prompting concerns about food safety and public health. Traditionally, bird flu was seen as a problem confined to poultry farms. But the spread to dairy cattle raises difficult questions. Could the virus mutate in ways that make human transmission easier? Could contaminated dairy products pose a new risk?

The question isn’t just how to contain the virus among birds and cattle, but how to stop it from reaching people. And the answer might lie in something as simple as citric acid.

The Pasteurization Problem:

For more than a century, pasteurization has been the gold standard for making milk safe. The process (heating milk to high temperatures to kill pathogens) was a game-changer when Louis Pasteur pioneered it in the 19th century. But the catch is, it requires expensive equipment, making it impractical for smaller farms.

That milk doesn’t just disappear. On farms, it’s often repurposed... to feed calves, for instance. If it contains live H5N1, it creates a direct pathway for viral transmission. In the U.S., fewer than 50% of large dairy farms pasteurize their waste milk, the byproduct of milk unsuitable for human consumption. This includes colostrum (the first milk after calving), milk from cows treated with antibiotics, and any milk that fails to meet quality standards. 

Which brings us to a simple but radical question: What if there was another way to neutralize the virus?

Low-Tech, High-Impact Solution:

Researchers at the University of California, Davis, recently stumbled upon a surprising discovery. By acidifying milk to a pH of 4.1 to 4.2 using citric acid, they found that they could effectively deactivate H5N1 without the need for heat, electricity, or specialized equipment.

“There can be a quite significant cost to have pasteurization as an option on the farm,” says Richard Van Vleck Pereira, veterinary epidemiologist at UC Davis and co-author of the study. “In our laboratory tests, we found that acidifying milk effectively deactivates the virus.”

The process isn’t just effective, it’s fast. Within six hours, the acidification method neutralizes the virus, making it safe for handling and even for feeding to pre-weaned calves. Unlike pasteurization, it doesn’t require refrigeration, further reducing costs and logistical challenges. The solution is cheap, easy to implement, and doesn’t require investing in large-scale equipment.

For now, pasteurization remains the primary safeguard against those risks. But the UC Davis research suggests that there’s room for innovation.

“We believe acidification is a novel and effective way to contain the spread of H5N1 on dairy farms and help protect livestock, pets, and people,” says Pereira.

Read More :

Skipping Deworming Because You Feel Fine? Here’s Why That Is A Dangerous Mistake