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Facts About the Flu

What is influenza?
The flu is a respiratory illness (it affects the nose, throat and lungs).  It is caused by one of the influenza viruses.  The flu affects people every fall and winter – that’s why the time of year from November to April is known as “flu season.”  The flu can cause mild illness or it can be serious.  In some people, it can cause severe illness, lead to hospital care, or cause death.

Symptoms of the flu:

  • Fever
  • Coughing
  • Sore throat
  • Runny or stuffy nose
  • Headaches
  • Body aches
  • Chills
  • Fatigue (feeling very tired)

Who can get the flu?
Flu viruses can affect people of any age.  Children are most likely to get sick because their immune systems aren’t strong enough to fight off the infection.

How the flu spreads:
Germs can spread through the air when a person with the flu coughs or sneezes.  Also, germs can be spread when someone touches a desk, doorknob or other surface that a person with the flu has touched. 

How to prevent the flu:

  • Get a flu shot.  The best way to keep from getting the flu is by getting a flu shot every year.  Plus, getting vaccinated not only protects you, it also protects your family and friends.  If you don’t get the flu, you can’t spread the flu!  This year, everyone who is 6-months of age and older should get the flu shot.

Take steps to protect your health everyday:

  • Cover your cough.  Cover your nose and mouth with a tissue when you cough or sneeze, then throw away the tissue.
  • Wash your hands often.  Use soap and water or an alcohol-based hand sanitizer.  Wash every time you eat, handle food, use the bathroom, change a diaper, touch a wound, blood or body fluids, and when they look dirty.   
  • Stay home when you are sick.  If you are sick, stay home from work, school and running errands (unless you need to seek medical care). Stay home until at least 24 hours after you no longer have a fever (100°F).  Avoid close contact with others.  This will help keep others from catching your illness.

Is the flu serious?
It is a myth that the flu is “no big deal.”  In fact, each year in the United States, on average:

  • 5 to 20% of people get the flu.  
  • More than 200,000 people are hospitalized from flu-related complications.
  • About 36,000 people die from flu-related causes.

Who is at risk for serious illness or flu-related complications?
Most healthy people who get the flu will get better without problems.  However, many people are at high risk for serious complications, such as:

  • People age 65 and older.
  • Children younger than 2 years old.
  • People who have other health conditions (such as diabetes, asthma, congestive heart failure, lung disease).

Complications can be serious, such as:

  • Bacterial pneumonia (an infection in the lungs).
  • Ear or sinus infections.
  • Dehydration (not enough water in the body).
  • Other medical problems may get worse.

Flu Viruses:
There are three types of flu viruses:  A, B and C.  The A and B viruses cause epidemics (widespread outbreaks in a country) of infection in people every year in the United States.

Flu viruses change from year to year, so that is why a new flu vaccine must be made each year to protect against the newer viruses.  The 2010-2011 seasonal influenza vaccine includes protection against three flu viruses, an H3N2 virus, an influenza B virus and the H1N1 virus that caused so much illness last season.  

What is a flu pandemic?
A flu pandemic is different from the regular flu season.  A pandemic is an outbreak of a new flu virus – one that people have little or no immunity to.
Since flu viruses are constantly changing, a flu pandemic can happen if three conditions are met:

  • A new influenza virus is introduced into the human population.
  • The virus causes serious illness in humans.
  • The virus spreads easily from person-to-person in a sustained manner.

In 2009, the H1N1 flu virus met all three conditions and caused a worldwide outbreak.  In late spring 2009, the World Health Organization declared that a H1N1 flu pandemic was underway. Over a year later, on August 10, 2010, the World Health Organization declared that the world was in a post-pandemic stage. 

This year, the H1N1 virus is still contagious and will circulate during the regular flu season.  However, for the 2010-2011 flu season, the flu vaccine includes protection against the 2009 H1N1 virus, plus two other flu viruses. 

What is the difference between a cold and the flu?
The flu and the common cold are both respiratory illnesses, but different viruses cause them.  They have similar symptoms (such as fever and sore throat), so sometimes it is hard to tell the difference. Here are some differences:

The Common Cold

The Flu

  • Usually mild illness.
  • Usually does not result in serious health problems, such as pneumonia, bacterial infections, or hospitalizations.
  • More likely to cause runny or stuffy nose.
  • In general, the flu is worse than the common cold.
  • Symptoms such as fever, body aches, extreme tiredness and dry cough are more common and more intense.
  • A doctor can give you a flu test within the first few days of illness to see whether you have the flu.


Printable Resources

  • Keep Germs Away Everyday (8.5 x 11 poster)
  •  Washing Hands (8.5 x 11 poster)
  • Cover Your Cough


More information on the Fight the Flu web pages

  • Fight the Flu - introduction 
  • Facts About the Flu
  • All About the Flu Shot
  • Flu Shot Clinic Schedule
  • Stop the Spread of Germs
Flu Treatment and Care