October 31, 2002

Peter Greaney, MD
Board-Certified Occupational Physician
President, WorkCare

The Straight Facts About the Flu and Its Vaccine

Despite global resources, the influenza (flu) virus continues to cause considerable morbidity and mortality each year. New strains of influenza, for which people have no immunity, appear periodically, at irregular intervals, causing worldwide pandemics. The first documented pandemic occurred in 1580. Since then, there have been 30 documented pandemics, including the Spanish Flu in 1918-1919 that was particularly virulent, killing about 40 million people. The CDC estimates about 76 million people are at high risk for complications from the flu, yet only half of this group receives the vaccine.

It is estimated that in the United States about 20,000 people die each year from the flu and another 114,000 are hospitalized for flu complications, including pneumonia. Most who die are over 65 years old. But small children less than 2 years old are as likely as those over 65 to have to go the hospital because of the flu.

In the United States , the flu season can range from November through March, and even past March in some years. During the past 19 flu seasons, months with the heaviest flu activity (peak months) occurred in December in 4 years, January in 5 years, February in 7 years, and March in 3 years.

Source (CDC National Immunization Program)

Influenza is a respiratory infection caused by viruses. Some of the symptoms are similar to a cold, and it can sometimes be difficult to tell if you have the flu or a very bad cold.

If you have the flu, you will have a sudden headache, dry cough, and you might have a runny nose and a sore throat. Your muscles will ache, you will be very tired, and you can have a fever up to 104°F (40°C). Most people feel better in a couple of days, but the tiredness and cough can last for two weeks or longer.

Influenza Vaccine

The influenza vaccine is the optimum method in preventing and reducing the severity of the flu.  However, a common sense approach in practicing good hygiene may also prevent exposure to the influenza virus. The virus is likely transmitted through small droplets.  Washing your hands, and observing good hygiene habits, such as covering your mouth and nose with tissue when sneezing may reduce the risk of spreading the virus.

On March 6, 2002 , the FDA Vaccines and Related Biological Products Advisory Committee made recommendations for the influenza virus strains to be included in the 2002-03 influenza vaccine.

The 2002-2003 trivalent vaccine consists of: 

• H1N1, A/New Caledonia/20-99
• H3N2, A/Panama/2007-99
  (an A/Moscow/10/99-like virus
• B/Hong Kong/330/2001-like virus strain

Who Should Get the Vaccine

Both adults and children who are in good health need flu shots to stay healthy.  Even if you aren't at high risk of complications, you should get a flu shot to prevent the flu and to protect everyone you live with and contact.

A report by the U.S. Advisory Committee on Immunization Practices issued the following statement:  "As vaccine first becomes available, efforts should be focused upon persons at high risk of complications associated with influenza disease and on healthcare workers."

Vaccination of the following groups should begin in October, regardless of the setting in which a person receives vaccination:

• Persons at increased risk for influenza-related complications (persons aged >65 years, persons aged 6 months--64 years with certain medical conditions, and healthy children aged 6--23 months);
• Healthcare workers;
• Household contacts of persons at increased risk for influenza-related complications (including contacts of infants aged <6 months who are not eligible for influenza vaccine); and
• Children aged 6 months to <9 years receiving influenza vaccine for the first time.

According to the CDC, "the current projected distribution of U.S. influenza vaccine for 2002--2003, on the basis of aggregate manufacturer's estimates, is 92--97 million doses, with the majority of doses expected to be distributed by the end of October. This projection is based on early estimates and might change as the season progresses. Thus, supplies are expected to be adequate for prioritization of persons at increased risk for influenza complications, their household contacts, and health-care workers for vaccination in October."

Source (CDC National Immunization Program)

Considerations Before Taking the Vaccine & Side Effects of the Vaccine

Before taking the vaccine, it's important to tell your healthcare professional if you have ever had any unusual or allergic reaction to influenza vaccine or to antibiotics classified as aminoglycosides or gentamicin and streptomycin.  Tell your healthcare professional if you are allergic to any other substances, especially eggs.

There is another known reaction to the vaccine called Guillain-Barre Syndrome (GBS).  This disease is a rare disorder affecting the nervous system, which results in paralysis.  Recovery is complete or nearly complete in 85% of the cases.  An average of 6% of persons with GBS will die. The cause of GBS is unknown and about 10-20 cases per one million adults occur in the United States each year.

Since the virus is inactivated, it cannot cause influenza.  The most common side effect is tenderness, redness or a hard lump at the place of injection.  Less common side effects include fever, general feeling of discomfort or aches and pain in muscle.

For more information and resources, click the following links:

CDC National Immunization Program

Timely Flu Bulletins, Vaccine Supply News, Patient Education, Reports for General Public, Healthcare Workers, and Media

Other CDC Sources

The Disease

Symptoms, treatment, complications and spread of flu.

Prevention and Control

Flu shots, availability of drugs, prevention, and traveling.

The Viruses

Types of influenza viruses, worldwide epidemics.

Flu Questions and Answers

Information on symptoms, vaccinations and myths, in a question-and-answer format.

Health Care Providers

Information for healthcare providers on vaccine and prevention and control of flu