H5N1 warning for raw milk

Milk is usually made safe with one step: heat. Pasteurization warms milk enough to knock out germs, which is why the Food and Drug Administration says it does not currently have concerns about the safety of pasteurized milk products nationwide. (fda.gov) Raw milk skips that step, so anything that got into the milk on the farm can stay there in the bottle. The Centers for Disease Control and Prevention says raw milk can carry Campylobacter, Escherichia coli, Listeria, Brucella, and Salmonella even before you add bird flu to the list. (cdc.gov) Highly pathogenic avian influenza A H5N1 is a bird flu virus that wild birds spread in droppings, water, and feed. Veterinary educator Deborah Thomson told dvm360 that the virus can move from wild birds into farm animals through contaminated feed and water, which is the route that turned a bird outbreak into a dairy-cattle problem. (dvm360.com) That dairy-cattle jump is the part that changed the raw-milk conversation in 2024. The Food and Drug Administration says federal and state agencies are investigating an outbreak affecting poultry, dairy cows, and people in multiple states. (fda.gov) Once the virus is in a cow’s udder, milk can carry a very large amount of virus. The Food and Drug Administration warned state regulators that all raw milk from herds with highly pathogenic avian influenza A H5N1 infections has the potential to contain infectious virus because it is not pasteurized. (fda.gov) This is not just a theory from lab dishes. A 2025 Nature Medicine study found that ferrets fed H5N1-contaminated raw milk became infected, which is why researchers said contaminated raw-milk products can pose a public-health risk. (nature.com) The virus also does not die quickly in cold milk. A Centers for Disease Control and Prevention study found slow decay of infectious H5N1 in raw milk, and a 2025 New England Journal of Medicine letter reported infectious virus in raw milk from infected cows after weeks of refrigerated storage. (cdc.gov) (nejm.org) Pasteurization changes that picture completely. The Food and Drug Administration and the United States Department of Agriculture said in September 2024 that two studies and a laboratory investigation using real-world equipment showed pasteurization completely neutralized H5N1 in milk and dairy products made from pasteurized milk. (fda.gov) The Centers for Disease Control and Prevention has been blunt with clinicians: people should not drink raw milk or eat raw-milk products in hopes of getting antibodies, and people should avoid uncooked food products such as unpasteurized milk from animals with suspected or confirmed H5N1 infection. (cdc.gov 1) (cdc.gov 2) Cats are another warning sign. The Centers for Disease Control and Prevention says feeding cats unpasteurized milk or raw meat from infected animals is a risk factor for H5N1, and the American Veterinary Medical Association has reported pet cats becoming ill or dying after consuming contaminated raw pet food and unpasteurized milk. (cdc.gov) (avma.org) Public-health officials are not saying every bottle of raw milk contains H5N1. The Centers for Disease Control and Prevention still says the current public-health risk to the general public is low, but that low overall risk sits next to a very specific warning: choose pasteurized milk and products made with pasteurized milk. (cdc.gov 1) (cdc.gov 2)