When people get flu, they tend to become ill quite quickly. Symptoms can include fever, chills, a headache and aching muscles, often with a cough and sore throat.
Around half of people infected with flu don’t even realise it, yet they can still spread the virus to others. This can sometimes cause serious illness leading to hospital care, and in rare cases, death.
Some COVID-19 symptoms are similar to flu so please check the latest advice and follow the current COVID-19 guidance available on the Welsh Government website.