A new strain of H5N1 avian influenza, D1.1, has been detected in dairy cows in Nevada, according to the US Department of Agriculture and the Centers for Disease Control and Prevention. This strain is more commonly found in wild birds and poultry, and has been linked to severe infections in humans. The detection raises concerns that the virus could be harder to eradicate from cattle than initially thought, as it may be reintroduced by wild birds.
Source: https://www.scientificamerican.com/article/new-bird-flu-strain-in-cows-and-animal-infections-raise-concern-for-human