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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.


Q.  Who should get a flu shot?

An annual flu shot is recommended for anyone who wants to reduce his or her chances of getting the flu. The flu shot is highly recommended for certain high-risk individuals who are more prone to flu complications, such as pneumonia. The CDC defines higher-risk people as the following:

  • People 50 years or older
  • People who live in nursing homes or long-term care facilities
  • People with certain chronic medical conditions
  • Women who are pregnant
  • All children age 6 months to 18 years.

The CDC also recommends that persons in close contact with someone in a high-risk group, people who care for children less than 6 months old, and health care workers be vaccinated.

Q. Do children need to get two doses of the flu vaccine the first time they are vaccinated?

Yes. A CDC study presented to the Advisory Committee on Immunization Practices panel showed that the flu vaccine in the past two flu seasons (2005-2006 and 2006-2007) was 75% effective -- but only if children got two doses the first time they were vaccinated.

Q.  Can the flu shot cause the flu?

No, the flu shot cannot cause the flu because it does not contain a live virus. This flu shot is an inactivated (killed) virus that is given with a needle. The nasal influenza vaccine called FluMist contains weakened viruses, which do not cause flu illness but sometimes can cause reactions such as runny nose, nasal congestion, and sore throat.

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.

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