Influenza, Adult

ExitCare ImageInfluenza ("the flu") is a viral infection of the respiratory tract. It occurs more often in winter months because people spend more time in close contact with one another. Influenza can make you feel very sick. Influenza easily spreads from person to person (contagious).


Influenza is caused by a virus that infects the respiratory tract. You can catch the virus by breathing in droplets from an infected person's cough or sneeze. You can also catch the virus by touching something that was recently contaminated with the virus and then touching your mouth, nose, or eyes.


Symptoms typically last 4 to 10 days and may include:

  • Fever.

  • Chills.

  • Headache, body aches, and muscle aches.

  • Sore throat.

  • Chest discomfort and cough.

  • Poor appetite.

  • Weakness or feeling tired.

  • Dizziness.

  • Nausea or vomiting.


Diagnosis of influenza is often made based on your history and a physical exam. A nose or throat swab test can be done to confirm the diagnosis.


You may be at risk for a more severe case of influenza if you smoke cigarettes, have diabetes, have chronic heart disease (such as heart failure) or lung disease (such as asthma), or if you have a weakened immune system. Elderly people and pregnant women are also at risk for more serious infections. The most common complication of influenza is a lung infection (pneumonia). Sometimes, this complication can require emergency medical care and may be life-threatening.


An annual influenza vaccination (flu shot) is the best way to avoid getting influenza. An annual flu shot is now routinely recommended for all adults in the U.S.


In mild cases, influenza goes away on its own. Treatment is directed at relieving symptoms. For more severe cases, your caregiver may prescribe antiviral medicines to shorten the sickness. Antibiotic medicines are not effective, because the infection is caused by a virus, not by bacteria.


  • Only take over-the-counter or prescription medicines for pain, discomfort, or fever as directed by your caregiver.

  • Use a cool mist humidifier to make breathing easier.

  • Get plenty of rest until your temperature returns to normal. This usually takes 3 to 4 days.

  • Drink enough fluids to keep your urine clear or pale yellow.

  • Cover your mouth and nose when coughing or sneezing, and wash your hands well to avoid spreading the virus.

  • Stay home from work or school until your fever has been gone for at least 1 full day.


  • You have chest pain or a deep cough that worsens or produces more mucus.

  • You have nausea, vomiting, or diarrhea.


  • You have difficulty breathing, shortness of breath, or your skin or nails turn bluish.

  • You have severe neck pain or stiffness.

  • You have a severe headache, facial pain, or earache.

  • You have a worsening or recurring fever.

  • You have nausea or vomiting that cannot be controlled.


  • Understand these instructions.

  • Will watch your condition.

  • Will get help right away if you are not doing well or get worse.