Facts about influenza: Influenza viruses change often. Therefore, influenza vaccine is updated each year to make sure it is as effective as possible. Protection develops about 2 weeks after administering the shot and may last up to a year. Influenza causes thousands of deaths each year, mostly among the elderly.
Who should get influenza vaccine?
- Everyone 50 years of age or older.
- Residents of long term care facilities housing persons with chronic medical conditions.
- Anyone who has a serious long-term health problem with:
- heart disease
- lung disease
- kidney disease
- anemia, and other blood disorders
- Anyone whose immune system is weakened because of:
- HIV/AIDS or other diseases that affect the immune system
- long-term treatment with drugs such as steroids
- cancer treatment with x-rays or drugs
- Anyone 6 months to 18 years of age on long-term aspirin treatment (who could develop Reye Syndrome if they catch influenza).
- Women who will be past the 3rd month of pregnancy during the influenza season.
- Physicians, nurses, family members, or anyone else coming in close contact with people at risk of serious influenza.
Others who should be considered for the vaccine include:
- People who provide essential community services.
- Persons traveling to the Southern hemisphere between April and September, or to the tropics at any time.
- Persons living in dormitories or in other crowded conditions, to prevent outbreaks.
- Anyone who wants to reduce their chances of catching influenza.
When should physicians administer influenza vaccine?
Because influenza activity can start s early as December, the best time to administer influenza vaccine is during October and November. Influenza vaccine can be given at the same time as other vaccines, including pneumococcal vaccine.
Can patients get influenza even if they are vaccinated?
Yes. Influenza viruses change often, and they might not always be covered by the vaccine. But vaccinated people who do get influenza often have a milder case than those who did not get the shot.
Also, many people call any illness with fever and cold symptoms "the flu." They may expect influenza vaccine to prevent these illnesses. But influenza vaccine is effective only against illnesses caused by influenza viruses, and not other illnesses.
What are the risks for patients from influenza vaccine?
The risk of influenza vaccine causing serious harm, or death, is extremely small. Almost all people who get the vaccine have no serious problems from it, however, mild side effects may arise, such as:
- Soreness, redness, or swelling where the shot was given.
In the event of a moderate or severe reaction, physicians should ascertain the date and time of the reaction as well as when the vaccination was administered. Physicians should contact the Vaccine Adverse Event Reporting System (VAERS) at 1-800-822-7967 or on the web.
Additional information is available from the CDC on Influenza.
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