Fighting the Flu(avian flu)

[RedEarth]

Fighting the Flu
summary tktktk
Issue of 2005-02-28
Posted 2005-02-21

This week in the magazine, Michael Specter writes about a particularly virulent strain of that has recently caused deaths in Southeast Asia. Here Specter discusses the virus and the general problems of the pandemic with Ben Greenman.

BEN GREENMAN: What is the avian flu, and why is it so dangerous?

MICHAEL SPECTER: Avian influenza is an infectious disease in birds that is caused by Type A strains of the influenza virus—the same strains that cause most flu-related sickness in humans. It occurs throughout the world and has been around for more than a hundred years. Often, avian influenza causes only mild symptoms. But when it is highly pathogenic, as is the case with the strain that is currently spreading though Asia, the virus can kill rapidly, with an almost one-hundred-per-cent mortality rate in birds. It is dangerous to humans for several reasons. First, it causes vast economic damage to the poultry farms and related businesses that it affects. Second, it can kill and cause severe disease in humans—though, so far, for that to happen a person would have to have been exposed at great length, or have eaten raw, infected poultry. But the biggest fear and the biggest danger is that the virus will mix with a more common human strain and mutate in such a way that it remains deadly but takes on the ability to pass easily among humans. If that were to happen, millions could die.

What does it take for a virus to cross the species barrier? How often does it happen?

It’s hard to say how often these viruses infect other species, because they often don’t make us sick, and therefore we have no idea we are even infected. It is rare for such a virus to mutate in a deadly way. The virus must first become capable of infecting other species.

The spectre in all discussions of the flu is the pandemic of 1918, which killed at least fifty million people around the world—and more Americans than died in combat in the twentieth century. There were also flu pandemics in 1957 and 1968, which, you note, were less devastating but still took millions of lives. Are we overdue for another one?

http://www.newyorker.com/printable/?online/050228on_onlineonly01