Flu shots

With winter approaching it’s time to get your annual flu shot.
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  • Updated:4 May 2007

02.What is flu?

Flu is caused by the influenza virus, which infects the respiratory tract (nose, throat and lungs). Two types of the influenza virus cause illness in humans — influenza A and influenza B.

However, influenza A viruses are the main cause of global epidemics, such as the ‘Spanish flu’ outbreak in 1918, which caused at least 20 million deaths worldwide. The ‘bird flu’ virus is also a subtype of the influenza A virus.

More than a cold

Some people use the terms ‘flu’ and ‘cold’ interchangeably, but the flu has more severe symptoms. These can include:

  • High fever
  • Headache
  • Extreme tiredness
  • Dry cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle aches and weakness
  • In some cases (particularly in children) stomach symptoms such as nausea, vomiting and diarrhoea

The main differences between the flu and a common cold are:

  • Colds cause a runny nose, while the flu usually starts with a dry feeling in the nose and throat.
  • Cold symptoms usually only last a few days while the flu can last up to a week.
  • The flu causes a higher fever.
  • Muscle pains and shivering attacks occur more commonly with the flu.

How is it spread?

  • The influenza virus is easily passed from person to person through droplets from coughs and sneezes. It’s estimated that droplets can carry up to 90 cm through the air and fall on the nose or mouth of another person.
  • The virus can also be passed on by touching an infected surface. So if someone with the virus coughs into their hands and then touches something, you could catch the virus by touching the same object and then touching your mouth or nose.
  • Generally, people who have the virus will be able to infect others from one day prior to feeling ill until five days after they first develop symptoms. Young children and people with weakened immune systems may be contagious for longer.
  • Children aged between five and nine have the highest rates of infection and the virus tends to spread quickly through day-care centres and schools.

You can help to control the spread of the illness by:

  • Staying at home and keeping your children at home if they’re infected.
  • Washing your hands in soap and running water for 10 seconds after coughing, sneezing or blowing your nose.
  • Covering your coughs and sneezes with a tissue and disposing of it in the garbage after use.
  • Getting vaccinated.


  • If you get the flu you should try to stay in bed, preferably until your temperature returns to normal.
  • Drink plenty of fluids (but no alcohol) and you may want to take paracetamol or aspirin to help relieve fever, headaches and muscle pain.
  • Prescription medications, such as oseltamivir (Tamiflu) and zanamivir (Relenza), can reduce the severity and duration of the illness if taken within two days of the first symptoms.

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