Influenza (Flu) Complications

British Columbia Specific Information

Influenza is an infection of the respiratory system caused by the influenza virus. Symptoms vary from mild to severe and can include fever, headache, runny nose, sore throat or cough. Influenza vaccines protect against the viruses that cause influenza. To learn more about influenza vaccines and to access influenza-related information from your health authority, visit Influenza (flu) season.

Register with the Get Vaccinated system for timely notifications of influenza immunizations. If you have already registered, you will be notified when it's time to book your appointment. You can register yourself or a family member (such as a parent, grandparent or child) using your Personal Health Number. Please note, registration is only required once. Learn more about fall immunizations from the Government of British Columbia.

Overview

Although most cases of influenza (flu) get better without causing other problems, complications sometimes develop.

Possible problems from the flu include:

  • Pneumonia, which is an infection of the lungs. It rarely causes death in young, healthy people. But it can often be life-threatening in older adults, people who have other diseases, and pregnant women.
  • Bronchiolitis. This is an inflammation of the small air passages. It affects infants and is the leading cause of serious lower respiratory illness.
  • Sinusitis. This means the mucous membranes that line the inside of the nose and facial sinuses become infected and inflamed.
  • Croup. Croup is a swelling or blockage in the windpipe. It causes hoarseness, a barking cough, a high-pitched sound when breathing in, and trouble breathing.
  • Chronic obstructive pulmonary disease (COPD) symptoms may get worse.
  • Inflammation of the heart muscle, the sac around the heart, or other muscles.

Credits

Current as of: October 31, 2022

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Christine Hahn MD - Epidemiology