In a groundbreaking discovery, dairy cows on farms across Texas and Kansas have been confirmed to have bird flu, marking the first such instances in the United States, and possibly, the world. There’s also suspicion that cows in New Mexico might be infected, though tests have yet to confirm this.
About three weeks ago, these cows started showing symptoms reminiscent of a cold, as reported by The Associated Press. The affected animals were producing less milk, showed a decrease in appetite, and seemed unusually tired.
The diagnosis came after unpasteurized milk samples and swabs from the cows’ throats and noses tested positive for the H5N1 strain of the bird flu, a highly pathogenic avian influenza. This strain is notorious for causing outbreaks among wild and domestic birds and has been known to infect humans on rare occasions.
This news follows closely on the heels of the first U.S. bird flu cases in goats, reported in Minnesota. These goats, which shared their living space with infected ducks and chickens, underscore the virus’s potential to jump across different animal species on farms.
The possibility of the virus spreading to other farm animals was highlighted by Brian Hoefs, Minnesota’s state veterinarian, emphasizing the need for vigilance.
Interestingly, the dairy cows in Texas seem to have contracted the virus from wild birds. However, there’s no evidence to suggest the virus has mutated to become more easily transmissible to humans.
In contrast to the drastic measures often required to control bird flu outbreaks in poultry, the infected cows showed signs of recovery without the need for treatment within a week to ten days. The infection rate among lactating dairy cows in the affected herds was about 10%, a stark contrast to the devastation seen in bird flocks.
The U.S. Department of Agriculture has reassured the public that only milk from healthy cows will enter the food supply and that pasteurization effectively neutralizes viruses and bacteria.
The H5N1 bird flu has been detected in 48 different mammal species to date, including foxes, skunks, raccoons, seals, and polar bears. This suggests that the jump to ruminants, such as cattle, goats, and sheep, was somewhat anticipated.
To date, there have been no reported cases of bird flu transmission from nonhuman mammals to humans in the U.S. The risk remains primarily with those who have direct contact with infected animals.
This development serves as a reminder of the interconnectedness of animal health and human health, underscoring the importance of monitoring and controlling such diseases to prevent potential public health risks.