(Also Called 'Flu')
What is influenza?
Influenza is a respiratory infection caused by a virus (germ). Influenza occurs most often during the winter and easily spreads from person to person. The "flu season" starts in December and usually lasts until spring.
Most people who get influenza feel sick for a week or two and recover. In some people, influenza leads to more serious lung infections.
What are the symptoms of influenza?
- Moderate to high fever
- Dry cough
- Sore throat
- Runny nose
- Loss of appetite
- Muscle aches
Fever, shaking chills, and shortness of breath are signs that influenza is getting worse.
Many conditions — such as a common cold, diarrhea, and vomiting — are called "the flu," but are not influenza.
Why is influenza more dangerous for elderly or chronically ill people?
People over 65 and those with chronic illnesses have a hard time fighting influenza because the body’s system for fighting infections is often weakened by age and illness. In older people, influenza is also more likely to lead to:
- Other infections
How can I tell the difference between a common cold and influenza?
Many cold and influenza symptoms are similar. Both common cold and influenza are caused by viruses. There are some differences with influenza. Symptoms of influenza often hit suddenly and cause you to become weaker and weaker. The dry cough and fatigue of influenza can last two to three weeks.
Signs that influenza is getting worse include:
- Shaking chills
- Shortness of breath
If you think that your illness is getting worse, contact your health care provider promptly.
How can influenza be treated?
Most people with influenza who are otherwise healthy do not need special drugs or treatments. If you have influenza, you should:
- Drink lots of fluids
- Eat a light diet
- Stay at home
- Take acetaminophen (such as Tylenol®) to reduce fever and relieve muscle aches
Note: Adults should not give aspirin to children or adolescents with fevers.
Are there medicines for bad cases of influenza?
If you are seriously ill, your health care provider might order an antiviral drug for you. Infections from bacteria are more likely when you have influenza. Health care providers treat these bacterial infections with antibiotic drugs. Common secondary infections include:
- Bacterial pneumonia
- Ear infections
- Sinus infections
Can influenza be prevented?
It is a good idea for everyone to get an influenza vaccine shot each year.
Yes. If you receive an influenza vaccine, you are likely to be protected from influenza for a year. The vaccine is given as a shot or a nasal spray. You must get the vaccine every year in the fall to be protected. Sometimes the vaccine does not prevent influenza but makes its symptoms less severe. The vaccine is safe, even for pregnant women. You cannot get influenza from the vaccine.
Who should get the vaccine?
It’s a good idea for everyone to get an influenza vaccine shot each year. You will protect yourself and other people. People who have a high risk of becoming seriously ill from influenza are urged to get a flu shot once a year. You should also ask your doctor about a pneumonia vaccination. You have a high risk if you have:
- Lung disease
- Kidney disease
- Heart problems
- An illness or are taking a medicine that makes it hard for your body to fight illnesses
- Severe anemia
You also have a higher risk of becoming seriously ill if you:
- Are over 65 years old
- Are under 18 years old and must take aspirin regularly
- Live or work in a nursing home
- Have AIDS
Other individuals who are not at high risk might also receive a flu vaccination. If you work in a healthcare facility, you may transmit influenza to others in a healthcare facility, but you are not at a higher risk of becoming seriously ill. The suggestion from the Centers for Disease Control and Prevention is that everyone over the age of 6 months gets a flu vaccine if there are no contraindications. This includes individuals who are not at high risk.
Who shouldn’t get the vaccine?
You shouldn’t get the influenza shot if you are:
- Severely allergic to eggs
- Sick with a fever (Wait until you are better.)
When should I get the vaccine?
The best time to get the flu vaccine is in the fall. The strongest time of protection is one to two months after you receive the vaccine.
- Centers for Disease Control and Prevention. Seasonal Influenza (Flu). Accessed 9/23/2013.
- US Department of Health & Human Services. Flu.gov. Accessed 9/23/2013.
- National Institute of Allergy & Infectious Disease. Flu (Influenza). Accessed 9/23/2013.
© Copyright 1995-2016 The Cleveland Clinic Foundation. All rights reserved.
Can't find the health information you’re looking for?
This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 9/20/2013...#4335