The symptoms of avian flu (bird flu) in humans are similar to those of other types of flu.
- a sudden high temperature (fever) of 38C (100.4F) or above
- a dry, chesty cough
- aching muscles
- limb or joint pain
- diarrhoea or stomach upset
- sore throat
- runny or blocked nose
- loss of appetite
- difficulty sleeping (insomnia)
These symptoms can come on suddenly. The time from infection to the start of symptoms (incubation period) is usually three to five days, although in some cases it can be up to seven days. Symptoms usually last for up to a week.
In many cases, bird flu can cause rapid deterioration, pneumonia (inflammation of the tissue of one or both lungs) and multiple organ failure, all of which can be fatal.
Read more about treating bird flu.