The bird flu virus was discovered in raw milk from the dairy farm based in Fresno, California.

The bird flu virus was detected in a retail sample of raw milk from a California-based dairy farm as cases continue to rise across the state, health officials announced.

The contaminated sample came from Fresno-based Raw Farm, California’s largest producer and marketer of raw milk. The tainted sample was discovered by officials with the Santa Clara County public health office, which has been testing raw milk already in retail stores across the state “as a second line of consumer protection.”

Raw Farms has since issued a voluntary recall of all quart and half-gallon dairy products produced in November. 9. Products are set to expire in November. 27 and have Lot ID #20241109.

No cases related to Raw Farms products have yet been reported.

“This is not surprising, given how quickly H5N1 appears to be spreading among farms in California and given the fact that these farm outbreaks are being detected in large part because of bulk milk testing raw from the farms,” ​​Jennifer Nuzzo. director of the Pandemic Center at Brown University, told the Los Angeles Times.

“What we don’t know is how much of a risk H5N1 poses to people who drink unpasteurized, infected milk.”

Only the “H5” part of the virus was detected in the sample collected, but health officials still believe it is likely still contaminated with H5N1. No case of H5 has been reported in the state nor has it been identified in any cow.

Mark McAfee, owner of Raw Farm, told the Los Angeles Times that this is the first time any of his products have tested positive for the virus since he began enrolling in voluntary testing in April.

But it’s not the first time Raw Farm has accidentally put contaminated products on the market. In February, the company had to issue a recall of its raw cheddar cheese products that were linked to an E. coli outbreak in multiple states. The dairy company was also linked to a salmonella outbreak in October 2023 that infected at least 165 people.

Nuzzo told the Los Angeles Times that findings from recent animal studies show that the bird flu virus “may pose a risk if ingested in sufficient quantities, but we have yet to see human cases resulting from consumption of raw milk. Since there are no reliable health benefits to consuming raw milk, I would personally avoid drinking it.”

Just last week, a child was reported to have contracted bird flu — the first case of a young person in California. Investigators still aren’t sure how she caught it, but have ruled out contact with infected milk — including raw milk — or poultry.

So far, the Golden State has seen 29 positive cases, all in dairy workers except the child. Only 55 cases of bird flu have been reported nationwide, with California accounting for about half of all cases.

The virus has also been detected at sewage sites in Santa Clara County, including Palo Alto, San Jose, Gilroy and Sunnyvale.

It has also been found in 24 of California’s 28 wastewater systems, according to testing by WastewaterScan.

States across the country have recently legalized raw milk products. President-elect Donald Trump’s nominee for Health and Human Services, Robert F. Kennedy Jr. has also indicated that he wants to increase the country’s access to and consumption of raw milk.