Bird Flu, Salmonella and Other Health Risks from Raw Eggs, Explained todayheadline

Can You Get Bird Flu from Eggs? Your Egg Safety Questions Answered

By Tanya Lewis edited by Jeanna Bryner

Eggs can be eaten in many different forms: scrambled, poached, fried, boiled or in omelets, soufflés, custards or meringues. But one way that food safety experts say they shouldn’t be consumed is raw.

That’s because eggs can harbor dangerous bacteria or viruses that can make us sick. The most familiar culprit is Salmonella, a bacterium that can result in a severe bout of food poisoning, causing diarrhea, stomach cramps and vomiting. The overall incidence of Salmonella in eggs is low: about one in 20,000. Nevertheless, “one of safest things to do is just cook food,” says Michael Persia, John W. Hancock Professor of Animal Sciences at Virginia Tech.

How to Store and Cook Eggs Safely

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To minimize Salmonella risk, commercial eggs in the U.S. are washed to remove bacteria and then kept refrigerated until they are sold. Consumers in the U.S. must refrigerate store-bought eggs because their outer antimicrobial coating, called the cuticle or bloom, gets removed in the washing process, Persia says. In Europe eggs can be stored at room temperature because they aren’t washed, leaving their bloom intact. Farmers market eggs in the U.S. may be washed or unwashed; even if they’re unwashed, it’s still a good idea to keep them in the fridge because they last longer.

Then there is pasteurization, a heating process that kills bacteria. Most whole-shell eggs you buy at the store are not pasteurized, so cooking them until they reach a temperature of 160 degrees Fahrenheit (71.1 degrees Celsius) is essential. A good rule of thumb is to cook eggs until the yolks are firm. In the U.S. all commercial egg products—such as liquid egg yolks and egg whites—are required to be pasteurized, however. Nursing homes, day cares and other places that serve people who may have weakened immune systems often use egg products for this reason.

Foods containing eggs should not be left out for more than two hours—or more than one hour if the ambient temperature is above 90 degrees F (32.2 degrees C). That said, plenty of baking recipes call for using room-temperature eggs, but you can just take them out of the fridge half an hour to an hour before baking.

Can You Get Bird Flu from Chicken Eggs?

In recent years, another nasty bug has been afflicting poultry and, in turn, egg production. A type of highly pathogenic avian influenza known as H5N1 has been circulating in wild birds and poultry, causing hundreds of outbreaks in U.S. birds since January 2022 and triggering egg shortages. But humans are unlikely to contract the virus from eating commercial chicken eggs, says Persia, who does biosecurity audits of poultry farms. “The risk is very, very, very low to nonexistent,” he adds. That’s because commercial farms have strict biosecurity measures to keep the domestic birds separate from wild ones, and H5N1 is so deadly to poultry that farmers must quickly cull an entire flock before the virus can contaminate any eggs, he says. “One of the biosecurity points that we actually look at from an audit standpoint is ‘If the bird is housed inside, is there any access that outdoor birds have to that?’” Persia says. “[Farmers] actually will put up different types of guards on the air inlet to make sure that birds don’t have access to that flock.”

That’s easier to do with indoor birds than outdoor ones. Backyard poultry pose a potential risk because they may have contact with wild birds or contaminants, Persia notes. He recommends feeding backyard birds inside, even if they have outdoor access, to avoid attracting wild birds. Another tip: use dedicated shoes when walking inside a chicken coop so you don’t tramp in pathogens from outside.

Dairy cows pose a different risk. When infected with H5N1, they don’t get as sick as chickens do, so these cows aren’t necessarily removed from the milking herd. Raw milk from infected cows contains high levels of H5N1, and cats have died from drinking it. But pasteurization kills the virus, so pasteurized milk is safe to consume.

More than 65 people in the U.S. have been infected with H5N1 since the beginning of 2024; most of them have been dairy and poultry workers. Infections in dairy workers have generally been mild, causing conjunctivitis and mild respiratory symptoms. But at least two people have become seriously ill from a strain of H5N1 related to the D1.1 genotype that is currently circulating in poultry and wild birds. Those two cases included one person in Louisiana who died from their infection. The Louisiana patient had had contact with both wild birds and backyard poultry.

The longer H5N1 is allowed to circulate in cows and poultry, the higher the likelihood it could adapt to spread among humans. But at least for now, you can rest easy in the knowledge that your eggs will be safe—so long as you cook them.