Pneumonia
الالتهاب الرئوي
An infection that inflames the air sacs in one or both lungs, which may fill with fluid, causing cough with phlegm, fever, chills, and difficulty breathing. It can range from mild to life-threatening, particularly in young children, older adults, and people with weakened immune systems or chronic conditions — making prompt medical evaluation important rather than assuming it's a routine chest cold.
This information is for general awareness only and does not replace professional medical advice. Consult a doctor for diagnosis and treatment.
Quick answer
Pneumonia is an infection of the lungs in which the air sacs (alveoli) become inflamed and may fill with fluid or pus. It is usually caused by bacteria or viruses and can range from mild to life-threatening.
Typical symptoms are cough (with or without phlegm), fever, chills, shortness of breath and chest pain when breathing or coughing. Older adults may mainly show confusion or weakness.
Diagnosis is based on examination and usually a chest X-ray. Treatment depends on the cause and severity — antibiotics for bacterial pneumonia, rest and fluids, and hospital care for severe cases. Breathing difficulty, confusion or blue lips need urgent care.
Symptoms
Cough
May produce yellow, green or bloodstained phlegm.
Fever, sweating and shivering
Shortness of breath and fast breathing
Chest pain
Often sharp and worse when breathing in or coughing.
Tiredness and loss of appetite
Nausea, vomiting or diarrhoea
Especially in children.
Confusion
Particularly in older adults, sometimes with little fever.
Symptom guides
Causes and risk factors
Causes
- Bacteria — Streptococcus pneumoniae is the most common cause of bacterial pneumonia.
- Viruses — Influenza, RSV, COVID-19 and others.
- Fungi — Less common, mainly in people with weakened immunity.
- Aspiration — Inhaling food, drink or vomit into the lungs.
Risk factors
- Age under 2 or over 65
- Smoking
- Chronic conditions — Lung or heart disease, diabetes, kidney or liver disease.
- Weakened immune system
- Recent viral illness or hospitalisation
- Difficulty swallowing or reduced consciousness
- Alcohol misuse
How is it diagnosed?
Pneumonia is diagnosed by combining symptoms, examination and tests, and severity is assessed to decide where treatment should take place.
Examination
Listening to the chest, checking breathing rate, oxygen level and temperature.
Chest X-ray
Shows the affected area of the lungs.
Blood tests
Blood count and inflammation markers, and kidney function in more severe cases.
Sputum, urine or swab tests
To identify the cause, mainly in more severe illness.
Pulse oximetry and further imaging
To assess oxygen levels and complications.
Related tests
Treatment
Treatment depends on the cause, severity and the person's health. It is decided by a doctor after assessment.
Antibiotics for bacterial pneumonia
The type and duration are chosen by the doctor; take the full course as prescribed.
Rest and fluids
Rest, drink plenty of fluids and treat fever and pain as advised.
Oxygen and hospital care
For low oxygen levels, severe illness, older age or other conditions; sometimes intravenous antibiotics and fluids.
Antivirals
For pneumonia caused by influenza or certain other viruses, in selected patients.
Follow-up
A cough and tiredness can last for weeks; a repeat chest X-ray may be advised in some people.
Antibiotics don't work against viruses; use only what your doctor prescribes.
When should you see a doctor?
Arrange a medical assessment if
- Cough with fever that isn't improving after a few days
- Breathlessness or chest pain when breathing
- Cough that brings up blood-stained or discoloured phlegm
- You are over 65, a young child, pregnant, or have a long-term condition
- Symptoms that improve and then worsen again
Seek urgent care if
- Difficulty breathing or rapid breathing at rest
- Blue or grey lips or fingertips
- New confusion, drowsiness or fainting
- Very high fever with shaking, or low body temperature with cold, clammy skin
- Chest pain that is severe or persistent
Prevention
Vaccination
Pneumococcal and annual influenza vaccines, and COVID-19 vaccination, as recommended for your age and health.
Don't smoke
Wash hands regularly
Manage chronic conditions
Such as diabetes and lung or heart disease.
Limit alcohol
Frequently asked questions
What is pneumonia?
An infection of the lungs that inflames the air sacs and can fill them with fluid or pus.
What are the symptoms of pneumonia?
Cough, fever, chills, shortness of breath and chest pain when breathing. Older adults may show confusion.
Is pneumonia contagious?
The germs that cause it can spread through coughs and sneezes, although not everyone exposed gets pneumonia.
How long does pneumonia last?
Many people improve within a week or two, but tiredness and cough can last several weeks.
Does everyone with pneumonia need hospital treatment?
No. Many people are treated at home, but hospital care is needed for severe illness, low oxygen levels or higher-risk patients.
Can pneumonia be prevented?
Vaccination, not smoking, good hygiene and treating chronic illness reduce the risk.
What is the difference between pneumonia and bronchitis?
Bronchitis affects the airways; pneumonia affects the lung tissue and is usually more serious.
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Medical sources
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