The detection of bird flu virus this week in a batch of unpasteurized milk sold in California underscores what health experts say are the known and potential risks of the products.

California health officials are warning not to drink another lot of raw milk from Fresno-based Raw Farm after it tested positive for bird flu virus. More testing of Raw Farm products is underway, the state said.

California state officials have suspended a company’s sales of raw milk to retailers amid ongoing concerns about bird flu. Raw milk sales by Raw Farm, located in Fresno, was blocked from distributing its raw dairy products as of Thursday, the Los Angeles ...