State health officials say the bird flu virus was detected in a retail sample of raw milk from a dairy in Fresno, California

The County of Santa Clara Public Health Laboratory had identified bird flu in one sample of raw milk purchased at a retail outlet. In response to this positive test, the California Department of Food and Agriculture will begin testing raw milk in bulk tanks for bird flu twice a week — instead of just once.

The H5N1 virus was found in a sample of unpasteurized milk at a store, prompting a recall of one batch. Health agencies have warned against the growing dietary fad.