Is it safe to eat beef, given the avian flu outbreaks in cows?

Infectious Diseases Staying Safe

A: The short answer is probably, but no one really knows. But: we do know that cooking your food properly and practicing good food safety to avoid cross-contamination is always SAFER. Reducing your risk is effective no matter what the risk was in the first place or how badly we understand it, so risk-reduction is smart practice even in highly uncertain situations.

Since the uncertainty involved makes it impossible to answer this question (and other similar avian flu questions) directly, here’s a short essay about uncertainty, avian flu, and my own lessons learned from answering hundreds of practical COVID-19 pandemic questions.

The upshot: We need to ask “how can we make this safer?” rather than “is it safe?”


Recent news in the U.S. has highlighted the detection of avian influenza in dairy cattle herds in 9 states, prompting many of our loyal readers here at Those Nerdy Girls to write in with practical questions about how to stay safe, such as “is it safe to eat beef?”

Other similar questions have included whether it’s safe to…

🧀 eat raw cheese

🐦 fill bird feeders

🐶 walk dogs on sidewalks covered in Canada goose 💩

And many others.

While these questions are important, they’re quite literally impossible to answer. Firm “yes” or “no” answers don’t exist or are impossible to estimate. In some cases, no one knows the answer. In others, things are so situationally specific that even if we had all the possible information about avian flu, we couldn’t formulate a universal answer. And forgive me for waxing philosophical, but what is “safe” anyway? Nothing in life is truly safe. You could get hit with a meteor while you eat that hamburger, H5N1 or no.


The avian flu situation, like COVID-19 in the early days, has many, many unknowns. Right now, the risk to humans is low. But it’s an emerging situation, and we all know that in an emerging situation, things can change rapidly and in unexpected ways. The recipe we’re working with has a ton of uncertainty. We (scientists) don’t know what will happen next, and to a very large extent we don’t even know what is happening right now.

Dairy cows are getting infected somehow, and we still don’t know how exactly.

We don’t know how widespread the infection is in cows because we aren’t systematically testing. We don’t know how many cows are infected and asymptomatic.

We don’t know if other species who live in close quarters with dairy cows also have widespread avian flu infections. There are reports of infections among barn cats, but without systematic testing, we have no idea how common this is or what role cats play in dairy cow infections. And what about pigs, horses, and other farm animals? We don’t know.

Wastewater surveillance for flu has picked up a few anomalies, but we don’t really know what to make of the wastewater data other than to say it’s offering a very incomplete picture. Since most farms and rural human residences are not on municipal sewage treatment systems, wastewater testing would not capture infections on most dairy farms. Also, from what we at TNG can puzzle out, wastewater surveillance detects any type A flu virus, not specifically H5N1–so we don’t even know if the anomalies are due to avian flu or localized outbreaks of a seasonal strain.

Although we know that wild waterfowl are highest risk for carrying avian influenza, we don’t really know how often songbirds get it. We don’t know the likelihood of the dust from your birdfeeder having infectious avian flu virus in it (though it seems low-ish based on general knowledge about how flu viruses work).

We don’t know how much infectious material is getting tracked into your house by your dogs. We don’t know how likely dogs are to get it from walking on goose 💩, or at all.

We don’t know how likely humans are to get avian flu from their dogs who were walking on dirty sidewalks. At the moment, this seems really unlikely but not out of the question.

We don’t know if, how, or when H5N1 will adapt to infect human cells readily. If that happens, we don’t know who will be most vulnerable, how deadly it could be, or how easily transmissible it will be. We don’t know precisely how well antivirals will work against a future version of the virus. We don’t know how long it would take to scale up and distribute a vaccine. We cannot tell the future.🔮


Here’s some better news: reducing your risk is effective no matter what the risk was in the first place. So risk-reduction is smart practice even in highly uncertain situations.

Also, we know a lot of things about flu viruses generally speaking and some things about this particular flu virus.

We know that sunlight and dry air will reliably kill RNA viruses, of which influenza is one. So does hand-washing. That’s why we say the birdfeeder is probably fine, and you can wash your hands after handling your bird feeder to further reduce your risk.

We know that masks are an effective way to reduce the risk of any disease that is transmitted by respiratory droplets. If it’s a dusty job, it won’t hurt you to wear a mask while you clean your bird feeders or clean your backyard chicken coop. This is a low-cost way to reduce your risk, no matter how minimal that risk is or how badly we can estimate it.


Back to the question: is it safe to eat beef?

We know that in general, people don’t get infected with flu virus by eating it. Usually, influenza is transmitted when an infected animal breathes/sneezes/coughs out infectious particles and another animal breathes them in (respiratory droplet transmission). Lots of other viruses are transmitted by eating or drinking them (like norovirus, rotavirus) but typically not flu. That said, we don’t know for sure that it’s impossible to get H5N1 via ingestion.

So, we don’t really know if it’s “safe” to eat beef. But we do know how to make eating beef safer.

A recent study showed that cooking to 145°F inactivated H5N1 in ground beef, but notably cooking to 120° did not. So no matter what we don’t know, we can improve our safety with what we do know.

Cook your hamburgers properly and practice good food handling safety to avoid cross-contamination.

Stay safer, stay healthier.