Patricia K. Farris, M.D., never thought she'd experience a natural disaster that would wipe out her practice, a city and an entire infrastructure. Then came Hurricane Katrina. "You couldn't call a patient who had a melanoma. It was so beyond, beyond," says Dr. Farris, who practices in Metairie, La. After the 2005 storm, she says, "I was out of business for seven months."