Overview Symptoms Causes

Influenza (commonly known as “flu”) is a contagious respiratory illness caused by flu viruses. It can cause mild to severe illness, and can sometimes lead to death. Flu is different from a cold and usually comes on suddenly.

“How Long Is the Flu Contagious?” and Other Flu-tastic Facts

How to Get Rid of a Cold Fast and Effectively

What are the symptoms?

  • Fever

    High temperature; feeling feverish or chills

  • Coughing and sneezing

    Coughing due to mucus in lungs and nasal passages

  • Sore throat

    Sore throat usually caused by nasal drip

  • Fatigue

    Tiredness and body weakness

  • Muscle or body aches

    Aching muscles and body aches, plus headaches, fatigue

How Long Does the Flu Last

People usually confuse the flu with a cold. There are indeed some similar symptoms but these two illnesses need to be distinguished from one another because they aren’t treated quite the same. The first difference is related to how quickly these two illnesses start taking action. The more common one, which is the cold, starts … Continue reading "How Long Does the Flu Last"...

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What causes it?

There are two main types of influenza (flu) virus: Types A and B. The influenza A and B viruses that routinely spread in people (human influenza viruses) are responsible for seasonal flu epidemics each year. Influenza A viruses can be broken down into sub-types depending on the genes that make up the surface proteins. Over the course of a flu season, different types (A & B) and subtypes (influenza A) of influenza circulate and cause illness.

More Information

Influenza A

Influenza A

Influenza B

Influenza B

Is there a test?

  • Rapid influenza diagnostic tests (RIDTs)

    These tests detects antigens, the parts of the virus that cause and immune response

  • Rapid molecular assays

    These tests detect the genetic material of the virus

  • Other tests

    Hospitals and medical laboratories have equipment to detect and confirm influenza virus