What Is The Flu?

What is Flu

What is the Flu?

You’re coughing. You’re sneezing. Your head feels feverish. Is it a cold? Or is it the dreaded flu? And what, exactly, is the flu?

The term ‘flu’ is often popularly used to refer to any number of illnesses. You may even have heard someone talk about a case of ‘stomach flu’, which usually means they were experiencing nausea, vomiting and diarrhea. This condition is actually not the flu at all, but likely a stomach condition called gastroenteritis.1

The condition influenza – or ‘the flu’ for short – is a respiratory infection that is different from the common cold, but rarely causes upset stomach or vomiting. Influenza affects many people. One reason the illness is so common is that flu can be caused by a number of different viruses.1

All flu viruses attack the body’s respiratory system – the lungs and the airways, including the throat and nose – causing classic flu symptoms.

Most commonly, flu symptoms include:1

  • Dry cough
  • Sore throat
  • Fever
  • Headache
  • Body chills
  • Muscle aches or body aches
  • Tiredness

It can sometimes be difficult to tell the difference between the flu and a cold by symptoms alone. However, in general flu has a quicker onset, has worse symptoms and may be associated with fever and muscle pain.2,3

Flu viruses are airborne viruses, meaning they travel through the air from person to person. The virus enters the body through the nose, mouth, or eyes – such as if you breathe it in, or touch your hands to your mouth, nose or eyes after your hands have picked up the virus Most often, this happens because people with the flu carry the virus on their hands, from coughing or sneezing into their hands. Healthy people commonly pick up the flu from hand-to-hand contact, or from touching objects that carry flu germs after being recently touched by someone who is sick.4

That means that one of the best ways to protect yourself from coming down with the flu is by frequently washing your hands during flu season. Getting an annual flu vaccine is also a good way to keep from getting sick.

In most cases, people with the flu will recover in 5 to 7 days. If you do experience flu symptoms make sure you have lots of rest and drink fluids.4 You can take an over-the-counter medicine to help decrease the severity of symptoms.4  

The flu can also be more serious, or even fatal, for elderly people, young babies or anyone with a weak immune system so consult your doctor if you are concerned about the flu.1


  1. Medline Plus Medical Encyclopedia. U.S. National Library of Medicine. National Institutes of Health. Entry accessed: Flu. http://www.nlm.nih.gov/medlineplus/flu.html
  2. Common Cold Centre. Cardiff University. General common cold information. Available at: http://www.cardiff.ac.uk/biosi/subsites/cold/commoncold.html. Accessed September 2010.
  3. WebMD Flu Guide. Available at http://www.webmd.com/cold-and-flu/flu-guide/is-it-cold-flu. Accessed September 2010.
  4. NHS Choices. Seasonal Flu, Available at http://www.nhs.uk/Conditions/Flu/Pages/Introduction.aspx. Accessed September 2010