Harvard Pychologists to help

While I would guess it is higher than 15%, this is a very important article from the SunHerald:

"When a natural disaster strikes, studies show that up to 30 percent of the
affected population will experience long-term negative psychological
effects.

A noted expert on disaster trauma estimates that the percentage for
Hurricane Katrina will be about 15 percent, but that is educated
guesswork.

Dr. Kevin J. Becker, director of the Institute for Trauma & Crisis
at Harvard Medical School, is on the Coast for a week, providing sessions on the
psychological response to disaster for the interested public and health care
providers.
"It's hard to get a handle on the numbers because there aren't
enough providers here to begin with," said Becker. "The response to a disaster
so much depends on who you are as a person and what resources you have
afterward.

"Everyone here is impacted, whether or not you had damage to your property,
and that is because the whole community is impacted."