Why do I need the flu vaccine every year?

Dr. Darria Long Gillespie, MD
Emergency Medicine
The strains of flu virus are different every year. In this video, I will discuss the importance of getting a flu vaccine every year.
The influenza virus changes its genetic makeup every year. That's why you can get the flu every year and why a flu vaccine containing the new virus is recommended annually for everyone six months and older.

This constantly changing virus presents a particular challenge to medical science, making it impossible to create a single vaccine to prevent the disease. Instead, the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) monitor each new strain of influenza virus as it appears, assessing which may be the predominant virus in the following year's flu season. Scientists use this data, collected by a surveillance network, to develop a vaccine each year against the specific virus they predict will predominate. 
Elizabeth A. Kelly, MD
Allergy & Immunology
There are many types, or strains, of the flu virus that change over time. Each year, scientists figure out which strains of the virus are most likely to reach the United States. The vaccine companies then make a new vaccine to fight those strains of virus. The vaccine is available each Fall.
Flu can be a serious disease, particularly among young children, older adults and people with certain chronic health conditions such as asthma, heart disease or diabetes. Any flu infection can cause serious complications, hospitalization or death, even in otherwise healthy children and adults. Getting a yearly flu vaccine is a safer choice than risking illness.
The Centers for Disease Control and Prevention (CDC) recommends a yearly flu vaccine for just about everyone six months and older. An annual vaccination is needed to get the best protection against the flu.

The presence of the CDC logo and CDC content on this page should not be construed to imply endorsement by the US Government of any commercial products or services, or to replace the advice of a medical professional. The mark “CDC” is licensed under authority of the PHS.

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Vaccines work to protect your body against germs. Because of vaccines, many of the diseases that can cause severe sickness, handicaps and death have been eradicated. Learn more from our experts about vaccines.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.