What is the flu? Influenza is a respiratory infection that produces fever, chills, sore throat, muscle aches, and cough that lasts a week or more. The flu can be deadly for the elderly and those with compromised immune systems or who are suffering from diabetes, kidney dysfunction and heart disease. Each year about 20,000 Americans, mostly in these high risk groups, reportedly die from flu complications such as pneumonia.
What is the flu vaccine? The flu vaccine is prepared from the fluids of chick embryos inoculated with a specific type(s) of influenza virus. The strains of flu virus in the vaccine are inactivated with formaldehyde and preserved with thimerosal, which is a mercury derivative.
Every year, federal health agency officials try to guess which three flu strains are most likely to be prevalent in the U.S. the following year to determine which strains will be included in next year's flu vaccine. If they guess right, the vaccine is thought to be 70 to 80 percent effective in temporarily preventing the flu of the season in healthy persons less than 65 years old (the efficacy rate drops to 30 to 40% in those over 65 years old but the vaccine is thought to be 50 to 60% effective in preventing hospitalization and pneumonia and 80% effective in preventing death from the flu in the over 65 age group). However, sometimes health officials do not correctly predict which flu strains will be most prevalent and the vaccine's effectiveness is much lower for that year.
Does the flu vaccine protect against all throat, respiratory, gastrointestinal and ear infections? The flu vaccine only protects against the three specific viral strains which are included in any given year's flu vaccine. Throat, respiratory, gastrointestinal and ear infections caused by bacteria or other kinds of viruses are not prevented by getting an annual flu shot.
Why do doctors say I have to get a flu vaccine every year? Like all vaccines, the flu vaccine only gives a temporary immunity to the virus strains or closely related virus strains contained in the vaccine. The only way to get natural and permanent immunity to a strain of flu is to recover naturally from the flu. Natural immunity to a particular strain of flu can be protective if that strain or closely related strains come around again in the future. However, because the vaccine only provides a 70 to 80 percent chance of temporary immunity to selected strains and those strains may or may not be prevalent each year, doctors say you have to get a flu shot every year.
Are there reactions to the flu vaccine? The most common reactions, which begin with 12 hours of vaccination and can last several days are: fever, fatigue, painful joints and headache. The most serious reaction that has been associated with flu vaccine is Guillain-Barre Syndrome (GBS) which occurs most often within two to four weeks of vaccination. GBS is an immune mediated nerve disorder characterized by muscle weakness, unsteady gait, numbness, tingling, pain and sometimes paralysis of one or more limbs or the face. Recovery lasts several months and can include residual disability. Less than 5 percent of GBS cases end in death.
What are contraindications to the flu vaccine? Among high risk factors listed by the CDC and the vaccine manufacturers are anyone who: (1) is sick with a fever; (2) has an impaired immune system; (2) has an egg allergy; (3) has a mercury allergy; (4) has a history of Guillain-Barre syndrome. In years past, pregnancy was also a contraindication to flu vaccine but, today, the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control (CDC) recommends flu vaccine for women more than 14 weeks pregnant.
The package inserts published by the flu vaccine manufacturers state that "Animal reproduction studies have not been conducted with influenza virus vaccine. It is also not known whether influenza virus vaccine can cause fetal harm when administered to a pregnant woman... Although animal reproductive studies have not been conducted, the prescribing health care provider should be aware of the recommendations of the Advisory Committee on Immunization Practices .The ACIP states that if used during pregnancy, administration of influenza virus vaccine after 14 weeks of gestation may be preferable to avoid coincidental association of the vaccine with early pregnancy loss."
Is Flu Vaccine Recommended for Children? The flu vaccine has never been recommended for healthy children. However, in the past few years there have been indications that health officials are soon going to recommend flu vaccine for all children. A nasal flu vaccine is scheduled to be on the market in late 2000 and publicity promoting this vaccine has centered on its potential use in children.
The current injectable flu vaccine contains mercury as a preservative. In the summer of 1999, the FDA, CDC and EPA directed the vaccine manufacturers to remove mercury as a preservative in childhood vaccines. Mercury is a known neuro-toxin and American babies under six months of age are currently exposed to mercury in childhood vaccines that exceed EPA safety standards.
One consideration with the mass use of flu vaccine in healthy children is the removal of natural antibodies to flu which are obtained from natural infection. The question of whether it is better for healthy children, who rarely suffer complications from flu, to get the flu and develop permanent immunity to that flu strain or it is better for children to get vaccinated every year to try to suppress all flu infection in early childhood is a question that has yet to be adequately answered by medical science.
What should I do? Become educated about the flu and its benefits and risks and the vaccine and its benefits and risks and make an informed decision after consulting multiple sources of information and discussing your questions with one or more health professionals.
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