Our Symptom checker provides clinical advice on what to do next based on your symptoms.
Pneumonia is an infection of the lungs, often caused by bacteria or viruses. It can be mild or very serious. Learn more about the illness.
Doctors diagnose pneumonia mainly by talking to the person who is unwell and examining them. A chest x-ray is also a good help.
The most common symptoms of pneumonia are cough, fevers, sweating and shivering, difficulty breathing, feeling generally tired and unwell, loss of appetite.
There are vaccines which reduce the risk of getting pneumonia. Learn why vaccination is recommended as a prevention for people in at risk groups.
What causes pneumonia?
Pneumonia is caused by an infection of the lung. Most infections are due either to bacteria or viruses.
The main treatment for pneumonia is antibiotics. In milder cases, they can be taken orally. In more severe cases, they’ll need to be taken by injection, at least at first.
Legionnaires' disease is a severe and sometimes life-threatening form of pneumonia. Read more information about symptoms, diagnosis, treatment and prevention.
Severe acute respiratory syndrome (SARS)
Severe acute respiratory syndrome (SARS) is a virus that can cause severe pneumonia. It spread from China in 2002-2003. Know what to do in a future outbreak.
Common in people of all ages, chest infections can occur alongside a cold or flu. Discover more about its causes, symptoms and treatment options.
Symptoms of serious illness in babies and children
If your child has a serious illness, it’s important to get medical attention quickly. Learn how to recognise the symptoms and what to do.