Influenza, Adult

Influenza ("the flu") is a viral infection of the respiratory tract. It causes chills, fever, cough, headache, body aches, and sore throat. Influenza in general will make you feel sicker than when you have a common cold. Symptoms of the illness typically last a few days. Cough and fatigue may continue for as long as 7 to 10 days. Influenza is highly contagious. It spreads easily to others in the droplets from coughs and sneezes. People frequently become infected by touching something that was recently contaminated with the virus and then touch their mouth, nose or eyes. This infection is caused by a virus. Symptoms will not be reduced or improved by taking an antibiotic. Antibiotics are medications that kill bacteria, not viruses.


Diagnosis of influenza is often made based on the history and physical examination as well as the presence of influenza reports occurring in your community. Testing can be done if the diagnosis is not certain.


Since influenza is caused by a virus, antibiotics are not helpful. Your caregiver may prescribe antiviral medicines to shorten the illness and lessen the severity. Your caregiver may also recommend influenza vaccination and/or antiviral medicines for your family members in order to prevent the spread of influenza to them.


  • DO NOT GIVE ASPIRIN TO PERSONS WITH INFLUENZA WHO ARE UNDER 18 YEARS OF AGE. This could lead to brain and liver damage (Reye's syndrome). Read the label on over-the-counter medicines.

  • Stay home from work or school if at all possible until most of your symptoms are gone.

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

  • Use a cool mist humidifier to increase air moisture. This will make breathing easier.

  • Rest until your temperature is nearly normal: 98.6° F (37° C). This usually takes 3 to 4 days. Be sure you get plenty of rest.

  • Drink at least eight, eight-ounce glasses of fluids per day. Fluids include water, juice, broth, gelatin, or lemonade.

  • Cover your mouth and nose when coughing or sneezing and wash your hands often to prevent the spread of this virus to other persons.


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


  • You develop shortness of breath while resting.

  • You have a deep cough with production of mucous or chest pain.

  • You develop nausea (feeling sick to your stomach), vomiting, or diarrhea.


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

  • You develop severe neck pain or stiffness.

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

  • You have a fever.

  • You develop nausea or vomiting that cannot be controlled.