The California Department of Public Health has confirmed that the U.S. Centers for Disease Control and Prevention has confirmed five human cases of H5N1, presumably genotype B3.13 acquired from cattle.  The workers were employed at three different dairy herd operations in the Central Valley. This presumes animal to human transmission. Cases presented with conjunctivitis and mild respiratory signs similar to patients in Texas, Michigan, Colorado and an unrelated event in Missouri.Follow up with family and co-habitant contacts is in progress. 

The CDC has characterized the virus, from the first two cases applying whole genome sequencing. This disclosed homogeneity with the  isolates of H5N1 from cattle, chicken flocks and free-living mammals.