Flu vaccine
Key points
- This vaccination protects people from contracting influenza, a viral illness affecting the respiratory tract.
- In the U.S., "flu" outbreaks typically occur in winter months.
- Children under age 9 require two shots one month apart the first time that they receive influenza vaccine.
- Most people achieve protection from influenza vaccine approximately 2 weeks after receiving the immunization.
Alternative names
Vaccine - influenza; Flu shot immunization; Influenza immunization (vaccine)
Definition
This vaccination protects people from contracting influenza, a viral illness affecting the respiratory tract.
Information
In the U.S., "flu" outbreaks typically occur in winter months. Symptoms of influenza include fever, chills, muscle aches, and cough. Although the illness usually only lasts 3 to 7 days, some people have more severe cases or complications that require hospitalization.
Thousands of people in the U.S. die each year as the result of the flu or its complications. Most of those who die are the elderly, young children, or people with compromised immune systems.
The viruses that cause influenza change rapidly. Influenza vaccines are developed each year to protect people from the strains expected to be most prevalent. All the viruses in the vaccine are killed, so it is not possible to get the flu from the vaccine. However, some people do experience a low-grade fever afterwards as their immune systems gear up to recognize the virus.
Flu vaccination is generally given at the beginning of the "flu season" - usually late October or early November in the United States. People traveling to other countries should be aware that influenza may occur at different times of the year in other areas.
IMMUNIZATION SCHEDULE
The vaccine is recommended for high-risk people 6 months and older as well as those in contact with them (including household contacts):
- all people 50 years or older
- adults and children with chronic lung or heart disease
- people with sickle cell anemia and other hemoglobinopathies
- residents of nursing homes (extended care facilities)
- residents of any institution housing people with chronic health problems
- people with kidney disease, anemia, severe asthma, or chronic metabolic illnesses (such as diabetes or chronic liver disease)
- people with immunological deficits (including those with cancer or HIV/AIDS)
- people receiving long-term treatment with steroids for any condition
- pregnant women who will be past the 3rd month of pregnancy during the flu season (you may want to consider requesting the mercury-free flu vaccine)
- children and teenagers receiving long-term aspirin therapy
The vaccine is also recommended for health care providers attending to high-risk people:
Written and revised by
David Cohen, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
health.am provides general information, not medical advice. Always consult a qualified health professional about your own health.