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What are the symptoms of flu?

In adults, common flu symptoms include:

  • a temperature of 38°C or higher
  • chills
  • sore throat
  • achy muscles, often in your arms, legs, neck, back and shoulders
  • tiredness
  • cough
  • blocked nose, or a runny nose
  • sneezing
  • headache
  • no appetite
  • wheezing when you breathe

Often, the flu will last a couple of days to a week, and you won’t need to see a GP.

However, see a GP if you’re pregnant, over the age of 65 or if your symptoms don’t get better after a week. If you have a chronic condition, such as diabetes, or a weakened immune system, you should also see a GP.

If you start coughing up blood, have chest pain or breathing difficulties, go to A&E or call 999 urgently.

Flu symptoms in children and babies

In children, the symptoms are the same as in adults, as listed above, but you should also look out for:

If your baby or child is showing severe symptoms, or if you’re worried about them, you should see a GP for more advice.

What’s the difference between a cold and the flu?

A cold and the flu are caused by different viruses, but can have similar symptoms, so it can be hard to tell them apart. Flu usually comes on a lot quicker than a cold, which can develop over a few days.

The flu usually has more severe symptoms than a cold too, as listed above. With a cold, you’ll usually only have a runny or blocked nose, a sore throat, sneezing, headaches and sometimes a cough.

The flu can also have serious complications, whereas a cold usually doesn’t have any lasting effects.

Complications caused by flu

Sometimes, the flu can lead to complications, some of which can be very dangerous. Complications may include:

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