Three Reasons You Might Need a Flu Shot This Year

You might need a flu shot this year because the flu is hitting some groups of people harder than it usually does. Most of the serious flu cases this year are causes by the H1N1 strain of the influenza virus. The groups that are affected more by this strain include:

  1. Younger People. In prior years, influenza has hit the very young and the very old most severely. But this year, young and middle-aged adults are being hit harder than usual. Medical epidemiologist Zack Moore of the North Carolina Division of Public Health says, “This year we’re seeing a lot of deaths in young adults and middle-aged adults — more than older adults.”
  2. Pregnant Women. Of the people hospitalized with the flu so far this year, 22% have been pregnant. Compare that to a more usual rate of less than 5%.
  3. People with Obesity. This year almost half of the people hospitalized with the flu have had obesity. That’s approximately twice the rate that’s usually seen.

What explains these differences? The best guess is that the H1N1 influenza strain is responsible. This strain is accounting for many cases of flu this year.It seems to hit younger people harder, particularly if their immunity might be affected by obesity, pregnancy, or a chronic disease. A recent study published in Obesity documents defects in CD4+ and CD8+ T cells that may contribute to the increased morbidity and mortality from H1N1 in people with obesity.

If you think it’s too late for a flu shot, think again. Says Joseph Bresee of CDC, “Flu season is by no means over, I expect this will go on for quite a few more weeks longer. The average flu season is 10 to 12 weeks, and we’re only a few weeks into it now.” Immunity begins to build very quickly after a flu shot, even though the full effect takes two to three weeks.

Click here to read more in USA Today and here to read more in Obesity.

Transporte de Influenza, photograph © Juan Araujo / flickr

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