Bird flu virus likely mutated within a Louisiana patient, CDC says

A genetic analysis suggests the bird flu virus mutated inside a Louisiana patient who contracted the first severe case of the illness in the United States. The U.S. Centers for Disease Control and Prevention reported the finding this week. Scientists believe the mutations may allow the virus to better bind to receptors in the upper airways of humans. One expert likened this to a lock and key. The virus needs a key that turns a lock to enter a cell. Though the virus may be changing to have a key that might work, the expert says it doesn't mean the world is closer to seeing a readily transmitted virus between people.