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Flu Shot Failure? Questions & Answers

The annual flu vaccine may not be as effective this year as in past years, the CDC has announced. Here's why.


Both the flu shot and FluMist work by causing antibodies to develop in your body. These antibodies provide protection against infection from the flu virus. The flu vaccine may cause low-grade fever, fatigue, and muscle aches in some people.

Q. How can I catch flu?

Flu is spread when you inhale droplets in the air that contain the flu virus, make direct contact with respiratory secretions through sharing drinks or utensils, or handle items contaminated by an infected person. In the latter case, the flu virus on your skin infects you when you touch or rub your eyes, nose, or mouth. That's why frequent and thorough hand washing is crucial to limit the spread of influenza.

Q. How do I know if I have a cold or flu?

Both cold and flu bring coughing, headache, and chest discomfort. With the flu, though, you are likely to run a high fever for several days and have headache, muscle aches, fatigue, and weakness. Usually, complications from colds are relatively minor, but a severe case of flu can lead to a life-threatening illness such as pneumonia.

Q. How is stomach flu different from flu?

It's not uncommon to mistake an intestinal bug or stomach flu (called gastroenteritis) for the flu. Gastroenteritis refers to irritation of the gastrointestinal tract (stomach and intestines). With gastroenteritis, you will have symptoms such as abdominal cramps, stomach pain, vomiting, nausea, and diarrhea. With flu, you will have symptoms such as high fever, headache, fatigue, respiratory congestion, and weakness.

Q. Do antibiotics treat flu?

No, antibiotics cannot conquer the flu virus because antibiotics only treat bacterial infections. Antibiotics may be helpful if there is a secondary bacterial infection. A few antiviral drugs are available to treat flu. Some antivirals may also reduce the severity and the duration of flu if started within the first 48 hours of flu symptoms.

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Reviewed on February 27, 2008

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