Cautious approach to swine flu

"I'm not ready to say that yet," Dr. Richard Besser, acting director of the Centers for Disease Control and Prevention, said when asked about indications by Mexican health authorities that the disease has peaked there.

Besser did tell network television interviewers that "what we're seeing is an illness that looks very much like seasonal flu. But we're not seeing the type of severe disease that we were worrying about." He noted that roughly 36,000 people die each year in this country from the winter flu, so it's still a serious matter.

At least 226 cases of swine flu virus have been confirmed in 30 states so far, and Besser said that "we are by no means out of the woods."

"In previous pandemics," he said, "there have been waves and you don't know what this virus is going to do."

Besser said health authorities also are concerned about indications that the flu had so far struck the young more heavily than older people, and that there still may be deaths from it.

He also said he didn't think it was necessarily time to ease off on school closings and other steps that have been taken to contain the spread of the infection.

"We're seeing infections in almost every state," Besser said, "and as that occurs, those who have underlying problems (such as the elderly and people with compromised immune systems) may be affected more .... It may be that this disease is starting first in children, and then moving to the elderly, so there's still much that we do not know."

Besser said that as a parent and a pediatrician, he thinks it's best for kids to be in school, whenever possible, and that adjustments in school shutdowns might be possible "as we learn and see that this virus is not more serious than ordinary flu."

Asked whether the food supply has been compromised, he said, "It may be that pigs have more to fear from people than people have to fear from pigs."

"With each day some of the uncertainty goes away, we learn more, and we're seeing encouraging signs," Besser said. "The encouraging signs have to do with severity." He summed up the situation by saying he was "precautiously optimistic" about trends now surfacing.

But he hastened to add that people still need to take everyday precautions, like vigorous and frequent hand washing, covering their noses and mouths when they sneeze and staying home when they're sick.

Besser said that what now ensues in the Southern Hemisphere, which is just entering flu season, will be "critically important for us to understand as we think about the decisions around vaccination."

The CDC chief was interviewed on CBS's "The Early Show" and NBC's "Today" show.