(MayoClinic.com) This year's annual flu shot will offer protection against H1N1 flu (swine flu) virus, in addition to two other influenza viruses that are expected to be in circulation this fall and winter.
Influenza is a respiratory infection that can cause serious complications, particularly to young children and to older adults. Flu shots are the most effective way to prevent influenza and its complications. The Centers for Disease Control and Prevention (CDC) now recommends that everyone 6 months of age or older be vaccinated annually against influenza.
Here are the answers to common questions about flu shots.
Because the flu vaccine is produced by private manufacturers, its availability depends on when production is completed. For the 2012-2013 flu season, manufacturers have indicated shipments are likely to begin in August and continue throughout September and October until all vaccine is distributed. Doctors and nurses are encouraged to begin vaccinating their patients as soon as flu vaccine is available in their areas.
It takes up to two weeks to build immunity after a flu shot, but you can benefit from the vaccine even if you don't get it until flu season starts.Why do I need to get vaccinated every year?
New flu vaccines are released every year to keep up with rapidly adapting flu viruses. Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses.
After vaccination, your immune system produces antibodies that will protect you from the vaccine viruses. In general, though, antibody levels start to decline over time — another reason to get a flu shot every year.Who should get the flu vaccine?
The CDC recommends annual influenza vaccinations for everyone age 6 months or older. Vaccination is especially important for people at high risk of influenza complications, including:
Chronic medical conditions can also increase your risk of influenza complications. Examples include:
Check with your doctor before receiving a flu vaccine if:
The flu vaccine comes in two forms:
Both the flu shot and the nasal spray help protect you from influenza. But there are differences to consider before deciding between the two.
|Flu shot||Nasal spray|
|Administered through a needle — you'll need an injection||Administered through a spray — you won't need an injection|
|Contains killed viruses — you can't pass the flu along to anyone else||Contains weakened live viruses that won't give you the flu but that can, in rare cases, be transmitted to others|
|Approved for use in people 6 months of age and older||Approved for healthy people ages 2 to 49 years|
|Can be used in people at increased risk of flu-related complications, including pregnant women and those with chronic medical conditions||Given only to nonpregnant healthy people, not to those with chronic medical conditions, suppressed immune systems, or to children and adolescents receiving aspirin therapy|
No. The flu vaccine can't give you the flu. But you might develop flu-like symptoms — despite getting a flu shot — for a variety of reasons, including:
Flu vaccines aren't 100 percent effective. According to the CDC, in past flu seasons when the match between flu vaccine and circulating strains of flu virus is close, a flu shot is between 60 and 70 percent effective in warding off influenza in all age groups combined.Can I lower my risk of the flu without getting a flu shot?
With or without a flu shot, you can take steps to help protect yourself from the flu and other viruses. Good hygiene remains your primary defense against contagious illnesses.
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