The Centers for Disease Control (CDC) is looking at whether or not the flu vaccine is effective. Preliminary results indicate you'll get just as sick (with colds, flu, flu-like illnesses) if you got the vaccine than if you didn't. Why doesn't the vaccine work? In order to understand the answer, you'll need to understand some specifics about the flu vaccine and a bit about how immunity works.
1. an antibody for one type of flu won't necessarily bind to a virus part from another type of flu. You don't get protection against other viruses.
2.You may not even get protection against the intended virus.
3. the flu vaccine will be more effective some years than others.
Bottom line: The flu vaccine varies in effectiveness from year-to-year. Even in a best-case scenario, it won't always protect against the flu. The CDC study didn't say that the vaccine didn't work; it says the vaccine didn't protect people from getting sick. Even with imperfect effectiveness, the vaccine is indicated for certain people. In my opinion, however, the vaccine isn't for everyone and certainly shouldn't be required for otherwise healthy people.
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1. an antibody for one type of flu won't necessarily bind to a virus part from another type of flu. You don't get protection against other viruses.
2.You may not even get protection against the intended virus.
3. the flu vaccine will be more effective some years than others.
Bottom line: The flu vaccine varies in effectiveness from year-to-year. Even in a best-case scenario, it won't always protect against the flu. The CDC study didn't say that the vaccine didn't work; it says the vaccine didn't protect people from getting sick. Even with imperfect effectiveness, the vaccine is indicated for certain people. In my opinion, however, the vaccine isn't for everyone and certainly shouldn't be required for otherwise healthy people.
More Here