A new variant of the H5N1 bird flu — the same one that led to the death of a Louisiana man — has for first the first time been found in infected U.S. dairy cattle.

Six dairy herds in Nevada have tested positive for a newer variant of the H5N1 bird flu virus that’s been associated with severe infections in humans, according to the Nevada Department of Agriculture.

Dairy cattle in Nevada have been infected with a new type of bird flu that's different from the version that has spread in herds since last year. U.S.