Chest Infection

Authored by Dr Sarah Jarvis, 18 Apr 2016

Patient is a certified member of
The Information Standard

Reviewed by:
Dr Hayley Willacy, 18 Apr 2016

A chest infection is an infection that affects your lower large airways (bronchi) and your lungs. Pneumonia and bronchitis are the most common chest infections. Bronchitis is usually caused by a viral infection. Pneumonia is usually due to bacterial infection. Pneumonia may be serious and need hospital admission.

None of us like colds - and none of us can avoid them unless we plan to live our lives in a sterile bubble. But even though they can't be 'cured', at least they settle with no ill effects within a few days. Chest infections, on the other hand, can range from mild but unpleasant to life-threatening - and catching them early is key to reducing the risk of serious complications. That's why it's essential to know how to spot the signs of a chest infection.

Your 'respiratory tract' runs from your nose all the way down to the alveoli - tiny air spaces deep inside your lungs. Doctors call the large airways (bronchi) of the lungs and the lungs themselves the lower respiratory tract. A chest infection is an infection affecting your lower respiratory tract. Any infection higher up (including your nose and throat) is known as an upper respiratory tract infection (URTI).

The vast majority of URTIs are caused by viral infections. Your immune system will fight these off without any help within a few days. Because URTIs are caused by viruses rather than bacteria, antibiotics won't help in any way.

Read more about antibiotics to treat respiratory tract infections.

infections of the respiratory tract

Sometimes an infection in the upper airways can spread deeper, causing a chest infection. Sometimes germs (bacteria) already living in your lungs can multiply, with the same result.

There are two main types of chest infection - acute bronchitis and pneumonia.

  • Acute bronchitis - bronchitis is inflammation due to infection of the bronchi. '-itis' is the medical term for inflammation. It can be acute or chronic. Acute means lasting a short time and chronic means lasting a long time. Acute bronchitis is common and is often due to a viral infection. Infection with a germ (bacterium) is a less common cause. See separate leaflet called Acute Bronchitis for more details.
  • Pneumonia - this is usually a bacterial infection of the lung and may be serious. Treatment with antibiotics is usually needed. See separate leaflet called Pneumonia for more details.
Chest infection

With a chest infection, you cough much more mucus up than a usual cold. If you cough up blood or rusty-coloured sputum, you should definitely see a doctor.

— GP Dr Julie Coffey, Is your cough really a chest infection?

Chest infections are very common, especially during the autumn and winter. They often occur after a cold or flu. Anyone can get a chest infection but they are more common in:

Further reading and references

i have stage 3 emphysema and use 3 liters of oxygen all day and night.  I have large rashes on both arms and upper chest.  I have sores inside my mouth at night I have a gurgling sound that seems to...

GiGi 1958
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