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.