Bird flu is often talked about as if it's one disease, but there are a variety of avian influenza strains, some of which have been discovered in humans and some of which have only been seen in birds. The authors of a new study took a close look at the first reported human patient with the H6N1 bird flu strain.

Most cases of the flu don’t lead to more than a few days home from work, or sometimes a hospital stay. In some cases, however, the flu can cause major respiratory problems and even death.

There is not yet a vaccine available to prevent the new bird flu strain seen in China, and doctors are still trying to determine the best way to treat patients with the virus.