U.S. dairy farm worker infected as bird flu spreads to cows in five states

Texas officials today issued a “health alert” about the first confirmed case of a human infection with a bird influenza virus that has found its ways into dairy cows. The worker developed conjunctivitis, a mild eye infection that frequently occurs when avian influenza viruses jump into humans. The case is the latest surprise in the global march of the flu strain, a subtype of H5N1 known as clade 2.3.4.4b that has devastated wild birds and poultry around the world for more than two years. The U.S. Department of Agriculture (USDA) says it has confirmed that the virus has infected cattle at farms in Texas, Kansas, New Mexico, and Michigan, while Idaho has a “presumptive” outbreak at one dairy farm. Wild birds, which have been found dead on some farms, most likely contaminated cow feed or water. Some evidence suggests the virus was transmitted between cows, but that remains unproven. And for now, USDA says it’s “initial testing has not found changes to the virus that would make it more transmissible to humans.”   Still, the widespread occurrence of H5N1 in mammals has renewed worries that it may evolve to become more transmissible between people.  And scientists are urgently trying to answer a host of questions, including how far the virus has spread among U.S. cows and how to prevent more herds and people from becoming infected. Although cows routinely contract influenza viruses, this is the first time that a “highly pathogen...
Source: ScienceNOW - Category: Science Source Type: news