Because the new swine flu virus is a highly unusual genetic mix of bird, flu and human viruses, health officials worry that it could continue to mutate and return in a more virulent form for next winter's flu season.
And, while most of the infections continue to cause only mild illness, similar to the seasonal flu, and virtually all patients recover quickly and fully, federal officials warned Friday that the swine flu outbreak in the United States is far from over.
"I want to address an issue that's been concerning me, that has to do with a sense of having dodged a bullet, a sense that this is over," Dr. Richard Besser, the CDC's acting director, said during a Friday teleconference. "While we have seen a lot of encouraging news in terms of severity, we continue to see hundreds and hundreds of new cases each day," he said.
While the swine flu -- technically known as the H1N1 virus -- is similar to seasonal flu, there are some important differences, Besser said. "One thing we are seeing, unlike seasonal flu, a higher percentage seem to be having vomiting and diarrhea," he said.
Meanwhile, a new Harvard University survey found that many Americans have taken measures to protect themselves and family members from the disease.
For instance, 67 percent of those surveyed said they or someone in their home are washing their hands or using a hand sanitizer more frequently, and 55 percent said they've taken steps to stay at home if they or a family member get sick.
"This outbreak has permeated a lot of American life," Robert J. Blendon, a professor of health policy and political analysis at the Harvard School of Publ
All rights reserved