The flu, also called influenza, is a respiratory infection caused by viruses. Each year, millions of Americans get sick with the flu. Sometimes it causes mild illness. But it can also be serious or even deadly, especially for people over 65, newborn babies, and people with certain chronic illnesses.
What causes the flu?
The flu is caused by flu viruses that spread from person to person. When someone with the flu coughs, sneezes, or talks, they spray tiny droplets. These droplets can land in the mouths or noses of people who are nearby. Less often, a person may get flu by touching a surface or object that has flu virus on it and then touching their own mouth, nose, or possibly their eyes.
What are the symptoms of the flu?
Symptoms of the flu come on suddenly and may include
- Fever or feeling feverish/chills
- Cough
- Sore throat
- Runny or stuffy nose
- Muscle or body aches
- Headache
- Fatigue
Some people may also have vomiting and diarrhea. This is more common in children.
Sometimes people have trouble figuring out whether they have a cold or the flu. There are differences between them. The symptoms of a cold usually come on more slowly and are less severe than symptoms of the flu. Colds rarely cause a fever or headaches.
What other problems can the flu cause?
Some people who get the flu will develop complications. Some of these complications can be serious or even life-threatening. They include:
- Bronchitis
- Ear infection
- Sinus infection
- Pneumonia
- Inflammation of the heart (myocarditis), brain (encephalitis), or muscle tissues (myositis, rhabdomyolysis)
The flu also can make chronic health problems worse. For example, people with asthma may have asthma attacks while they have flu.
What are the treatments for the flu?
Most people with the flu recover on their own without medical care. People with mild cases of the flu should stay home and avoid contact with others, except to get medical care.
But if you have symptoms of flu and are in a high risk group or are very sick or worried about your illness, contact your health care provider. You might need antiviral medicines to treat your flu. Antiviral medicines can make the illness milder and shorten the time you are sick. They also can prevent serious flu complications. They usually work best when you start taking them within 2 days of getting sick.
Can the flu be prevented?
The best way to prevent the flu is to get flu vaccine every year. But it's also important to have good health habits like covering your cough and washing your hands often. This can help stop the spread of germs and prevent the flu.