With reports of the first human death from bird flu in the US, some Americans are feeling an uncomfortable flashback to the early days of Covid-19, when infectious disease experts were talking about a new virus that was sending people to the hospital with respiratory infections.

The damage to those commercial industries has been severe. By the CDC’s accounting, bird flu has struck down nearly 131 million poultry and been found in 919 dairy herds across the country. The agency said there have been 66 confirmed human cases in the U.S. since last year, almost all of them people who worked on farms with infected cows or birds.

A person hospitalized with H5N1 bird flu has died, marking the first fatality linked to the currently circulating infection in the US. Human-to-human spread has not been detected, so what's the real risk?

The experiment of whether H5 can ever be successful in human populations is happening before our eyes,” Seema Lakdawala, a flu virologist at Emory University, told me. “And we are doing nothing to stop it.

Any time a person catches H5N1, or bird flu, their infection is a chance for the virus to mutate in the wrong direction. When someone dies from the bird flu—as an elderly Louisiana man did on Jan. 6,

The bird flu virus circulating among cows, poultry and wild birds isn't yet a threat to the general public, but experts say if and when that will change is impossible to predict — and that if things do get bad,