Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. Flu is different from a cold. Flu usually comes on suddenly. People who have flu often feel some or all of these symptoms:
- fever* or feeling feverish/chills
- sore throat
- runny or stuffy nose
- muscle or body aches
- fatigue (tiredness)
- some people may have vomiting and diarrhea, though this is more common in children than adults.
*It’s important to note that not everyone with flu will have a fever.
Call 999 or go to A&E if you:
- develop sudden chest pain
- have difficulty breathing
- start coughing up blood
Boosting your immune system is the best way to prevent yourself from catching any virus, including influenza and the range of rhinoviruses that cause colds and flu.