What is Influenza (flu)? The flu is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year.

Every year in the United States, on average:

-  5% to 20% of the population gets the flu
-  more than 200,000 people are hospitalized from flu complications
-  about 36,000 people die from flu

Some people, such as older people, young children, and people with certain health conditions (such as asthma, diabetes, or heart disease), are at high risk for serious flu complications.

Symptoms of Flu

-  fever (usually high)
-  headache
-  extreme tiredness
-  dry cough
-  sore throat
-  runny or stuffy nose
-  muscle aches
-  stomach symptoms, such as nausea, vomiting, and diarrhea, 
   also can occur but are more common in children than adults.

Complications of flu can include bacterial pneumonia, ear infections, sinus infections, dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.

How Flu Spreads

Flu viruses spread mainly from person to person through coughing or sneezing of people with influenza. The main way that illnesses like colds and flu are spread is from person to person in respiratory droplets. This is called "droplet spread."  Droplets from a cough or sneeze of an infected person move through the air and are deposited on the mouth or nose of people nearby.  Sometimes people may become infected by touching something with flu viruses on it and then touching their mouth or nose.  We know that some viruses and bacteria can live 2 hours or longer on surfaces like cafeteria tables, doorknobs, and desks.  Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 days after becoming sick. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick.

Cover your mouth and nose

If you are sick, cover your mouth and nose with a tissue when coughing or sneezing. It may prevent those around you from getting sick.  You may be asked to put on a surgical mask to protect others.  

Avoid close contact

Avoid close contact with people who are sick. When you are sick, keep your distance from others to protect them from getting sick too.  Stay home when you are sick.  If possible, stay home from work, school, and errands when you are sick. You will help prevent others from catching your illness.

Good Health Habits for Prevention

The single best way to prevent seasonal flu is to get vaccinated each year.   Good health habits like washing your hands often can help prevent respiratory illnesses like the flu. There also are flu antiviral drugs that can be used to treat and prevent the flu.

Clean your hands 

Washing your hands often will help protect you from germs. Wash with soap and water or clean hands with alcohol-based hand sanitizer.

Avoid touching your eyes, nose or mouth

Germs are often spread when a person touches something that is contaminated with germs and then touches his or her eyes, nose, or mouth.

Practice other good health habits

Get plenty of sleep, be physically active, manage your stress, drink plenty of fluids, and eat nutritious food.