"This is the beginning of the flu season, there's plenty of vaccine out there," said Dr. Tom Frieden, director of the U.S. Centers for Disease Control and Prevention. "Get a flu shot to prevent yourself, your family and your community.... Flu is a potentially serious illness."
Frieden said 171 million doses of flu vaccine are being produced for this season, with about 40 million doses already distributed. He said that amount of vaccine would be enough to meet demand.
The current vaccine, which has been modified to target a strain that causes millions of illnesses last year, "should be a good match against this season's influenza, but only time will tell," Frieden said.
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The CDC for the past five years has recommended that everyone older than 6 months get vaccinated. Despite that recommendation, less than half of the U.S. population, or an estimated 47 percent, got a flu vaccine last season, and just 34 percent, for the 18-to-49-year-old age group received a vaccination.
"Unfortunately, many people are still unaware of this universal recommendation," said. Dr. Kathleen Neuzil, director of the Center for Vaccine Development at the University of Maryland School of Medicine.
Neuzil said some people avoid getting vaccinated because they believe they are "invincible." But even those people can get the flu, and should get vaccinated to prevent themselves from getting sick, and from spreading the flu to other people particularly vulnerable to the bug, including children, seniors and pregnant women.
A recent study found that people over the age of 65 were less likely to get a flu-related illness when a third of younger adults in their area are vaccinated.
Officials noted that people can get flu shots in a variety of locations, including from their doctors, pharmacies and workplaces.
Frieden said that increasingly, "businesses recognize that vaccinating their employees is very good business," because it reduced worker absenteeism due to the flu.