Influenza vaccine

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Influenza vaccines

Influenza

Overview

Influenza vaccine

Definition:

This vaccine protects people againstthe flu.

Alternative Names:
Vaccine - influenza; Immunization - influenza; Flu shot; Flu vaccine
Information:

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The flu is a contagious respiratory disease caused by an influenza virus. In the U.S., flu outbreaks typically occur in winter months. Symptomsinclude fever, chills, sore muscles, and cough. Thousands of people in the U.S. die each year from the flu or its complications. Most of those who die are the elderly, young children, or people with compromised immune systems.

See article on the flu for more information.

The viruses thattypically causethe fluare primarily categorized as influenza type A or type B.Influenza type B does not change much over time, but type A can mutate rapidly. Therefore, a new form of the flu vaccine must be developed each year to protect people for the exact strain that is expected to be most prevalent.

All the influenza viruses in the flu shot are killed (inactive), so it is not possible to get the flu from this type ofvaccine. However, some people do experience a low-grade fever for a day or two after the shot as their immune systems gear up to recognize the virus. (See "Risks" section in this article.)

A new nasal spray-type flu vaccine calledFluMist is proving to be effective and safe in healthy people aged 5 to 49 years old. The FDA-approved vaccine helps the lining of the nose fight offactual viral infections.(FluMist uses a live, weakened virus instead ofa dead one like the flu shot.) In one study, the nasal sprayprovided protection against the flu in up to 93% of children. It is not approved for young children or people with asthma.

Fluvaccines are generally given at the beginning of the "flu season" -- usually late October or early November in the U.S. People traveling to other countries should be aware the flu may occur at different times.

IMMUNIZATION SCHEDULE

According to the U.S. Centers for Disease Control andPrevention,anyone who wants to reduce their risk of the flu can get a flu shot. The flu shot is approved for anyone older that 6 months of age. Some people have a higherrisk of the disease. You should be vaccinated each year if you:

Are50 or older
Have chronic lung or heart disease
Have sickle cell anemia and other hemoglobinopathies
Live in a nursing homeor extended care facilities
Live in any type of housing where there arechronic health problems
Have kidney disease, anemia, severe asthma, diabetes, or chronic liver disease
Have a weakened immune system (including those with cancer or HIV/AIDS)
Receive long-term treatment with steroids for any condition
Expect to be past the 3rd month of pregnancy during the flu season (you may want to consider requesting the mercury-free flu vaccine)