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    The Flu Vaccine Works -- But Few Give It a Shot


    Each year, scientists work to develop a vaccine aimed at the virus strain that they anticipate will cause illness in that given year. In years when there is a good match, the flu vaccine is as much as 90% effective in preventing the flu in healthy adults, according to the CDC.

    At least 20,000 Americans die from the flu and its complications each year; most of the victims are over 65, according to the U.S. Department of Health and Human Services.

    In the U.S., the most-recent flu season began in mid-December 1999 and peaked between Dec. 25, 1999 and Jan. 15, 2000.

    And although the flu typically peaks in December through March, there have been outbreaks during summer months, according to the new study. In fact, the flu peaks from May to August in parts of the Southern Hemisphere.

    "In the last three summers, there have been documented influenza outbreaks among travelers," Bridges says. "When you get a whole bunch of people together on bus tours and ships from all parts of the world, you are bound to have respiratory illnesses."

    This summer, people traveling in large groups to the tropics or to the Southern Hemisphere -- which includes most of South America and Africa, as well as Australia -- may be exposed to the influenza virus and should get vaccinated if they have not already been, she says.

    "People don't recognize that traveling in the summer is a potential risk," Bridges continues. "If you haven't already got vaccinated, talk to your doctor or a travel medicine specialist."

    Flu vaccines are made in limited quantities so it may be hard to track down a vaccine at this point in the year, Bridges says. Travel medicine specialists still are likely to have some available, she adds.

    For more information on preventing influenza while traveling, visit the CDC's traveler's health page at

    Vital Information:

    • The World Health Organization recently announced that few people between the ages of 50 and 64 get a yearly flu shot. The CDC is changing its recommendations to encourage more people in this younger age group to be vaccinated.
    • At least 20,000 Americans die each year from the flu and its complications. Most are over 65, but people with chronic illnesses and weakened immune systems also are at high risk.
    • In the U.S., flu season usually runs through the winter, reaching its peak somewhere between December and March. But people can catch it in the summer, too, especially if they travel.

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