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Flu update: This year, reducing your risk for the flu will require two kinds of shots

Updated: November 01, 2009

Flu update

This year, reducing your risk for the flu will require two kinds of shots

In a typical year, 5% to 20% of Americans get the flu, more than 200,000 require hospitalization, and about 35,000 die from the infection. However, 2009 isn't a typical year. We're in the midst of a flu pandemic (a pandemic is a worldwide epidemic) caused by a virus that first emerged in Mexico in February — 2009 H1N1, formerly known as "novel H1N1" or "swine flu." For many of us, that may mean getting two kinds of flu vaccine: one for ordinary, seasonal flu and another for the pandemic strain.

Most people have no immunity to 2009 H1N1. But how severe the illness will be is unknown. So far, it appears to be no more lethal than the seasonal flu. But flu viruses are more contagious and cause more widespread disease in cold weather. The 2009 H1N1 virus first emerged and spread in the northern hemisphere during spring and summer, and most experts think it will likely produce more widespread disease in the fall and winter.

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