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JAMA Patient Page
October 8, 2014

Influenza Vaccine

JAMA. 2014;312(14):1482. doi:10.1001/jama.2014.12301

The best way to protect yourself from getting influenza is to get vaccinated every year.

What Is Influenza?

Influenza, also called “the flu,” is caused by the influenza virus. It affects the lungs and can cause symptoms such as fever and trouble breathing. Most people recover from the flu on their own. But, in some people who are older or have long-term medical problems, the flu can be a serious or even deadly illness.

Influenza is a seasonal illness and affects most people during the winter months. In the United States, January and February tend to be the worst months for flu, but people can get the flu as early as October and as late as May. Each year the virus changes slightly, and the resulting different types of viruses are called strains. Some strains cause more serious illness than others. These strains are sometimes given special names, such as “swine flu” (H1N1) or “avian flu” (H5N1 and H7N9).

Why Get the Influenza Vaccine?

The flu vaccine helps prevent people from becoming sick after being exposed to the influenza virus. Getting vaccinated not only helps to prevent you from getting sick but also can prevent you from spreading the virus to others. As a result, the influenza vaccine has benefits both for individuals and for communities as a whole.

Each year, the flu vaccine becomes available during the fall season. Because the virus changes each year, a new vaccine is developed every year that is specially tailored to protect against the most common flu strains that year. In other words, last year’s vaccine may not work as well for this year’s virus. This is why people get vaccinated for the flu every year.

Who Should Get Vaccinated?

The US Centers for Disease Control and Prevention recommends that all individuals older than 6 months get a flu vaccine every year.

In cases in which there may not be enough vaccine for everybody, vaccination efforts should focus on people who are more likely to be exposed to the flu virus or who are more likely to become very sick from the illness. These include people who are older than 50 years or between 6 months and 4 years of age, have long-term medical problems, are pregnant, or are health care workers.

Is It Safe to Get the Vaccine?

The flu vaccine is generally safe, with very few side effects. It can be given either as a spray into the nostrils or as a shot into the muscle. The side effects mostly involve discomfort at the site where the vaccine was given. Your doctor will tell you what type of vaccine preparation (shot or spray) is best for you.

Some preparations of the vaccine are made with eggs and cannot be given to people with severe egg allergies. But there are also preparations available that contain no egg products and are safe for people with egg allergies. Ask your doctor about these egg-free preparations if you have a severe egg allergy.

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Article Information

Source: Centers for Disease Control and Prevention

Topic: Infectious Disease/Preventive Medicine