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Part 1, Chapter 12: Manual Appendix III

Influenza and Influenza Vaccine


Influenza (or "flu") is a viral infection of the bronchial tubes and lungs that can make someone of any age ill.  Usually the flu occurs in the United States from about November to April.  If you get the flu, you usually have fever, chills, cough, and soreness and aching in your back, arms, and legs.  Although most people are ill for only a few days, some persons have a much more serious illness and may need to go to the hospital.  On average, thousands of people, most elderly, die each year in the United States from the flu or related complications.


Because influenza is usually mild and most people recover fully, health officials emphasize the use of vaccine for the elderly and people with other health problems most likely to be seriously ill or to die from the flu or its complications.  For example, people who after even light exercise become short of breath because of diseases affecting their hearts or lungs, and people who have low resistance to infections, are likely to be more seriously affected by the flu.  Thus, the following groups are at highest risk for serious illness with the flu and have been particularly recommended to receive vaccine:

Adults and children with long-term heart or lung problems which caused them to regularly see a doctor or to be admitted to a hospital for care during the past year.

Residents of nursing homes and other institutions housing patients of any age who have serious long-term health problems.

Other members of the public who are at moderately increased risk for serious illness with the flu and who public health authorities feel should be vaccinated if possible are:

Healthy people over 65 years of age.

People of any age who during the past year have regularly seen a doctor, or been admitted to the hospital for treatment of kidney disease, cystic fibrosis, diabetes, anemia ("low blood"), or severe asthma.

People who have a type of cancer or immunologica1 disorder (or use certain types of medicine) that lowers the body's normal resistance to infections.

Certain health workers who provide care for high risk patients also should be vaccinated, to reduce the possibility that these patients might catch the flu when receiving medical care.


The viruses that cause flu frequently change, so people who have been infected or given a flu shot in previous years may become infected with a new strain.  Because of this, and because any immunity produced by the flu shot will possibly decrease in the year after vaccination, persons in the high-risk groups listed above should be vaccinated every year.  This year's flu shot contains the strains to provide immunity against the types of flu which have been circulating in the past year and are thought to be most likely to occur in the United States next winter.  All the viruses in the vaccine are killed so that they cannot infect anyone.  Vaccine will begin to provide its protective effect after about 1 or 2 weeks, and immunity may decrease, on average, after several months.  Flu shots will not protect against colds and other illnesses that resemble the flu.


Only a single flu shot Is needed each season for persons older than 12 years, but children 12 years or less may need a second shot after about a month.  The doctor or nurse giving the flu shot will discuss this with parents or guardians.  Children should be given only vaccine that has been chemically treated during manufacture ("split virus") to reduce chances of any side effects.  Split-virus vaccine can also be used by adults.


Most people have had no side effects from recent influenza vaccines.  Flu shots are given by injection, usually into a muscle of the upper arm.  This may cause soreness for a day or two at the Injection site and occasionally may also cause a fever or achiness for 1 or 2 days.  Current Influenza shots have not been linked to the paralytic Illness Gulllain-Barre Syndrome.  As is the case with most drugs or vaccines, there is a possibility that allergic or more serious reactions, or even death, could occur with the flu shot.


Persons with an allergy to eggs that causes dangerous reactions if they eat eggs.

Anyone who has ever been paralyzed with Guillain-Barre Syndrome, as well as women who might be or are pregnant.

Persons who are ill and have a fever.

QUESTIONS:  If you have any questions about influenza or Influenza vaccination, please ask now or call your doctor before requesting the vaccine.