Influenza

Influenza is a contagious respiratory infection caused by influenza viruses.

Influenza primarily affects the respiratory tract and commonly causes sudden fever, cough, sore throat, headache, muscle aches, fatigue, and other symptoms. The illness can range from mild to severe and can lead to complications such as pneumonia.

Influenza is distinct from the common cold, although the two can produce similar respiratory symptoms. Certain antiviral medicines can be used to treat or prevent influenza in appropriate circumstances, particularly for people at increased risk of complications.

QUICK FACT

Influenza is not simply a severe common cold. Although the symptoms can overlap, influenza is caused by influenza viruses and can produce more substantial systemic illness and complications.

COMMONLY CONFUSED WITH

Common cold: The common cold can be caused by many viruses, whereas influenza is caused by influenza viruses.

SEE ALSO

Clinical & Educational Context

Discussed in Health Articles & Guides

Explore how "Influenza" is covered across our evidence-based editorial guides:

1 Article
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