A highly contagious strain of bird flu plagues farmers across the U.S.

The U.S. is in the midst of its worst deadly bird flu outbreak in years. Millions of poultry and wild birds have been killed. And although the risk to human health is low, the impacts have trickled down to consumers. William Brangham traveled to the Midwest, where producers and scientists are desperately trying to stay ahead of the virus. Watch here.