Global pandemic fear as chicken flu kills man
"Flu viruses change slightly every year. Every few decades, though, they mutate dramatically, producing a significantly different strain to which humans are more vulnerable. A virus that jumped from animals to humans would produce a significant mutation... But there were fears at the time that, if the virus cross-bred with a milder flu that did move from person to person, it could produce a dangerous strain that would move rapidly around the world."

Global pandemic fear as chicken flu kills man
"Flu viruses change slightly every year. Every few decades, though, they mutate dramatically, producing a significantly different strain to which humans are more vulnerable. A virus that jumped from animals to humans would produce a significant mutation... But there were fears at the time that, if the virus cross-bred with a milder flu that did move from person to person, it could produce a dangerous strain that would move rapidly around the world."