Influenza is diagnosed by its symptoms, typically headache, aching limbs, fever, high temperature, runny nose and feeling a general weakness.

Bed rest will be advised for the first few days. Antibiotics will not work on viral infections but they may be prescribed to prevent secondary infections in some cases.

People who are more vulnerable to bronchitis or pneumonia following a bout of influenza are the elderly and anyone with diabetes or a chronic lung or heart condition.