Raw milk — H5N1 warning
Public-health officials linked a recent outbreak to raw milk from a California farm and are warning people not to drink unpasteurized milk because it can carry H5N1 bird flu — pasteurization kills most harmful bacteria without materially changing milk’s nutrients. (contagionlive.com) Veterinarians note the virus can move from wild birds into farm animals through contaminated feed and water, and that raw meat or milk could pose human risk, so this isn’t just a theoretical hazard. (dvm360.com)
Milk is usually made safe with pasteurization, which is a short burst of heat that works like running dishes through a hot sanitizing cycle before anyone eats off them. The Centers for Disease Control and Prevention says that step kills harmful germs in milk, and the Food and Drug Administration says it inactivates bird flu virus too. (cdc.gov) (fda.gov) Raw milk skips that heat step, so anything that got into the milk at the farm can stay there all the way to the bottle or cheese block. The Centers for Disease Control and Prevention says drinking unpasteurized milk can cause serious illness, and the Food and Drug Administration says raw milk from infected herds can contain infectious highly pathogenic avian influenza H5N1 virus. (cdc.gov) (fda.gov) Highly pathogenic avian influenza H5N1 is a bird flu virus that for years was mostly a poultry problem, but in March 2024 it was found in United States dairy cows for the first time. The Centers for Disease Control and Prevention says the dairy-cow outbreak was first reported on March 25, 2024, and that the virus has since been detected in many mammals. (cdc.gov) The way this jumps species is not mysterious. Veterinarian Deborah Thomson said wild birds can contaminate feed and water, and farm animals can then pick up the virus from that environment. (dvm360.com) Once a cow is infected, milk becomes part of the exposure problem. The Centers for Disease Control and Prevention says infected birds and other animals can spread avian influenza viruses to people through body fluids, including cow milk. (cdc.gov) That is why public-health agencies keep drawing a bright line between pasteurized dairy and raw dairy. The Food and Drug Administration and the United States Department of Agriculture said in September 2024 that pasteurization completely neutralized H5N1 in their studies of milk and dairy products. (fda.gov) The warning is not based only on laboratory theory. A July 2024 report in Contagion Live said a Salmonella outbreak linked to Raw Farm in Fresno, California, sickened at least 165 people, which it described as the largest United States outbreak tied to raw milk in the past decade. (contagionlive.com) The same California company is back in outbreak news now for a different germ. On April 3, 2026, the Centers for Disease Control and Prevention said it was investigating a multistate Escherichia coli outbreak linked to raw cheese and raw milk sold by Raw Farm, LLC. (cdc.gov) Bird flu has not been confirmed in people from drinking raw milk, but the Centers for Disease Control and Prevention says drinking unpasteurized milk can make you sick, and it separately warns that raw milk is a concern in the H5N1 response. In September 2025, the agency said no human H5N1 infections had been attributed to raw cow’s milk so far, while still noting that influenza viruses can potentially infect the digestive tract. (cdc.gov 1) (cdc.gov 2) So the practical rule is simple: if the label says pasteurized, the heat step has already done the safety work; if it says raw, it has not. The Centers for Disease Control and Prevention says pasteurized milk lets people keep milk’s nutritional benefits without the infection risk that comes with unpasteurized dairy. (cdc.gov)
