SACRAMENTO, the United States -- California's battle against avian influenza A (H5N1) intensified amid spreading infections across dairy farms and a growing number of human infection, including two newly confirmed cases in Stanislaus and Los Angeles counties.

Gov. Gavin Newsom’s declaration has riled up concern, particularly in other top dairy-producing states, such as Wisconsin and Pennsylvania.

California officials have declared a state of emergency over the spread of bird flu, which is tearing through dairy cows in that state and causing sporadic illnesses in people in the U.S.

Bird flu virus has swept through farms across the nation’s largest dairy producing state. All human cases had been mild - until now.

California officials have declared a state of emergency over the spread of bird flu, which is tearing through dairy cows in that state and causing sporadic illnesses in people in the U.S. That raises new questions about the outbreak of the virus,

Public health officials on Monday reported the first case of bird flu in a person in Stanislaus County this year. The individual, who officials said had contact with infected dairy cattle, experienced mild symptoms and was treated with antivirals.

At least 65 human cases of H5 bird flu have been confirmed this year, with the majority being detected in California.

The LA County Department of Public Health confirmed the first human case of bird flu in the county, just days after Gov. Gavin Newsom issued a state of emergency over the disease.

Los Angeles County health officials reported the first human case of bird flu in the area less than a week after a statewide emergency declaration was announced.

A human case of the bird flu has been confirmed in Stanislaus County, according to health officials. Stanislaus County Public Health, California Department of Public Health, and the Centers for Disease Control and Prevention reported the bird flu (H5N1 avian influenza) in a county resident who had contact with infected dairy cattle.