NewsHealth & MedicineWhat bird flu experts are watching for in 2025Theyre eyeing the cattle outbreak, viral genetic changes and federal actions Dairy farm workers are among the most vulnerable people to H5N1. About two-thirds of the 66 human bird flu cases in the U.S. since early 2024 came from exposure to infected cattle.ANGELA WEISS/AFP via Getty ImagesBy McKenzie Prillaman10 seconds agoAfter a year of rising bird flu cases among people in the United States, researchers are keeping a watchful eye on the H5N1 virus to slow further spread.Since early 2024, the country has recorded 66 cases of highly pathogenic avian influenza caused by H5N1. Farm workers who caught the virus from infected cattle or poultry make up most cases. The first human death related to the disease was announced January 6, but other recent illnesses have often been mild, with symptoms such as pink eye, fever and a cough.