U.S. Dairy Cattle Test Positive for New Strain of Bird Flu

A concerning development in the ongoing battle against bird flu has emerged as U.S. dairy cattle have tested positive for a strain of the virus that had not been previously seen in cows. The U.S. Department of Agriculture made the announcement, highlighting the potential risks associated with the spread of the virus.

The H5N1 virus has had significant impacts on the agricultural industry, leading to reduced milk output in cattle and driving up egg prices by decimating millions of hens. Additionally, the virus has infected nearly 70 people since April, underscoring the urgent need for containment measures.

The discovery of the new strain, known as the D1.1 genotype, in dairy cows in Nevada marks a significant milestone. Previous bird flu infections among dairy herds had been attributed to the B3.13 genotype, making this new finding a cause for concern.

Genome sequencing of milk samples from Nevada revealed the presence of the D1.1 strain, which had been previously identified in wild birds. This strain was also detected in a teenager in British Columbia and in a fatal case in Louisiana, highlighting the potential risks associated with its spread.

The USDA’s testing program for bird flu in dairy cattle identified the D1.1 genotype, which was prevalent among wild birds during the fall and winter months. The virus’s ability to adapt and infect mammals poses a significant challenge for farmers and veterinarians.

According to Beth Thompson, South Dakota’s state veterinarian, the virus is evolving rapidly, necessitating enhanced safety measures to protect livestock. J.J. Goicoechea, Nevada’s agriculture director, emphasized the need for increased vigilance to prevent further spread of the virus.

In response to the detections in Nevada, herds in two counties have been placed under quarantine to prevent the virus from spreading. Gail Hansen, a veterinary and public health consultant, stressed the importance of containing the outbreak to prevent it from reaching other dairy cattle populations.

Experts warn that dairy herds previously infected with other strains of bird flu may be at risk of reinfection with the new D1.1 strain. Gregory Gray, a professor studying cattle diseases, expressed alarm at the potential consequences of the virus’s evolution.

As the agricultural industry grapples with the threat of bird flu, it is crucial for authorities to implement stringent containment measures to protect livestock and prevent further spread of the virus.