The viruses that cause influenza are continually changing.
Each year, the World Health Organization identifies three strains of the influenza virus that are predicted to be the most common. Vaccines are then developed based on these three viruses. Since these may change from year to year, you need an annual influenza shot to make sure your body forms antibodies against the new influenza viruses.
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The recommended time for influenza immunization is from October to December.
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Where can I get an influenza shot?
Ask your doctor or local public health office about getting an influenza shot.
Some employers organize workplace clinics for their employees.
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How long does it take for the vaccine to work?
Maximum protection develops by about 2 weeks after vaccination and lasts up to a year.
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How effective is the vaccine?
Influenza vaccination has been shown to prevent illness in approximately 70-90% of healthy children and adults.
Some vaccinated people might still get influenza, but usually experience mild symptoms. You might also get another strain of influenza that the vaccine was not designed to protect against.
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Are there side effects from the vaccine?
Influenza vaccine is very safe, but like any medication, side effects can occur. Most people who get the vaccine have either no side effects or mild effects such as soreness, redness or swelling where the shot was given. Some people may get a fever or muscle aches that start shortly after vaccination and may last 1-2 days. If you experience red eyes, a cough or difficulty breathing within 2-24 hours call your doctor. Severe allergic reactions are extremely rare. If they do occur it is within a few minutes to a few hours after vaccination.
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Who should, and should not, get an influenza shot?
The influenza shot is recommended for anyone who wants protection from influenza. However, the vaccine is provided free of charge to only those who have a high risk of complications from influenza (see below).
For medical reasons some people should not get an influenza shot (see below), otherwise anyone over the age of 6 months can be immunized.
It is especially important for the following people to get an influenza shot:
- Children six months to 23 months
- Family members and caregivers of all children under 24 months
- Anyone with chronic heart or lung disease
- Anyone with diabetes or other metabolic disease, cancer, kidney disease, a blood disorder or a weakened immune system
- Anyone 6 months to 18 years on long-term treatment with acetylsalicylic acid (ASA)
- Anyone, including children, who lives in the same household or is in contact with people at risk such as those mentioned above
- Pregnant women who are at high risk for influenza-related complications (as listed above)
- Seniors and anyone who lives, works or volunteers in a nursing home, chronic care facility, retirement home or other healthcare setting
- Health care workers who have contact with high risk individuals (as listed above)
Some people should NOT get an influenza shot. In general these include:
- people who are severely allergic to eggs (chicken eggs are used in the production of the vaccine)
- people who have had a severe allergic reaction to a previous influenza vaccine
- children under 6 months of age, because the vaccine does not work well in this age group
If you have a fever on the day you are supposed to get your influenza shot you should wait until the fever has gone.
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I'm healthy, why should I get the influenza shot?
The influenza shot is the most effective and longest lasting protection against the influenza virus and the illness it can cause.
In addition to the usual five to ten days of serious illness, it can take weeks to fully recover, interrupting work, recreation and family activities.
Further, as more people are vaccinated, the influenza virus has less chance to multiply and circulate. Protecting yourself can also benefit those around you who may be at risk of severe complications from influenza. However, the vaccine is provided free of charge to only those who have a high risk of complications of influenza (see previous question).
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Can I get influenza from the vaccine?
No. Influenza vaccine cannot cause influenza because it is made from killed viruses. People who think they got influenza from the vaccine could be confusing their symptoms with those of another virus, or an allergy.
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Why do children under 9 years of age need two influenza shots?
Like many childhood vaccines, the influenza vaccine needs a booster in children to make sure the body produces the necessary antibodies.
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Can I get an influenza shot if I'm pregnant or breastfeeding?
Yes. Influenza vaccine is considered safe and is beneficial for pregnant women at all stages of pregnancy who are at high risk for influenza related complications.
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What does the influenza shot cost?
For people at risk of the complications from influenza, shots are available at no charge through your Regional Health Authority.
If you are not eligible for a free influenza shot, you can expect to pay about $15-20 to a health care provider, agency or clinic.
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