Flu (influenza), seasonal

Bacterial infection

The most common complication of seasonal flu is a bacterial chest infection. Occasionally, this can become serious and develop into pneumonia.

A course of antibiotics usually cures the bacterial infection, but it can very occasionally become life-threatening, particularly in the frail and elderly.

Other serious complications are uncommon.

Rare complications

Rare complications include:

• tonsillitis,
• otitis media (a build-up of fluid in the ear),
• septic shock (infection of the blood that causes a severe drop in blood pressure),
• meningitis (infection in the brain and spinal cord), and
• encephalitis (inflammation of the brain).

Glossary

Kidney

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Acute

Acute means occuring suddenly or over a short period of time.

Antibiotics

Antibiotics are medicines that can be used to treat infections caused by micro-organisms, usually bacteria or fungi. For example amoxicillin, streptomycin and erythromycin.

Heart

The heart is a muscular organ that pumps blood around the body.

Lung

Lungs are a pair of organs in the chest that control breathing. They remove carbon dioxide from the blood and replace it with oxygen.

Fever

A high temperature, also known as a fever, is when someone's body temperature goes above the normal 37°C (98.6°F).