Influenza is widespread in most of the United States, with the incidence continuing to increase in some states while declining slightly in others, Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, said at a news conference Tuesday.
The infections are "overwhelmingly" pandemic H1N1 influenza, commonly known as swine flu, he noted.
Frieden noted that the public has three major concerns about vaccination "despite the clear message that vaccine is the best tool to protect against the flu":
First, he said, many people believe the flu is a mild illness. It is not. "It can make you pretty sick, knock you out for a day or two or three," Frieden said. "It can even put you in the hospital or kill you."
Second are concerns that the vaccine is not safe, that corners have been cut in its production and that it is a new, experimental vaccine. "In fact, none of that is the case," he said. "It is made the same way the flu vaccine is made each year, in the same facilities and by the same companies."
Third is the concern that the vaccine is arriving too late to do much good. "It's too soon to say it is too late" because no one knows what is going to happen for the rest of the flu season. "We don't know what the long flu season is going to hold," Frieden said. "We have not had a flu season like this in 50 years."