Bronchitis, or acute bronchitis, is an infection in your lungs’ bronchi or larger airways. It usually occurs due to a viral infection.
Pneumonia is an infection in the lungs’ air sacs. It usually happens as a result of a bacterial infection.
However, it is important to note that both bronchitis and pneumonia can result from viruses, bacteria, or even fungi.
Read on to find out more about the causes of chest infections. This guide also discusses symptoms, treatments, when to contact a doctor, and more.

Symptoms of a chest infection can depend on the type of chest infection you have. However, symptoms generally include:
- chest congestion
- wet cough
- coughing up yellow or green mucus
- wheezing
- shortness of breath
- fever
- headache
- muscle aches
- tiredness
Symptoms of a chest infection usually follow the cold or the flu. They should improve within around 7–10 days, according to the National Health Service (NHS). However, it can take up to 1 month for symptoms to resolve, depending on severity.
You may experience a cough and mucus for up to 3 weeks.
The cause of a chest infection will depend on the type of chest infection you have.
In most cases, a virus will cause bronchitis. However, it may also occur due to a bacterial or fungal infection. Learn more about bronchitis.
Pneumonia usually occurs as a result of a bacterial infection, but it can also have viral or fungal causes. Learn more about pneumonia.
Fungal chest infections, such as fungal bronchitis or pneumonia, are rare but possible.
The treatment your doctor recommends can depend on the type of chest infection.
If you have acute bronchitis, you may not require medical treatment. You should be able to manage the condition at home, and symptoms should clear up within 3 weeks.
Your doctor may prescribe antibiotics for a bacterial chest infection, such as pneumonia. Before they do so, they may need to take a sample of mucus to identify the type of infection.
Learn about the types of antibiotics.
You can try various remedies to help manage a chest infection at home. These include:
- drinking plenty of water, which can help loosen mucus and make it easier to cough up
- taking pain relief medication to alleviate symptoms, such as:
- fever
- headaches
- muscle pain
- drinking hot water with lemon and honey to alleviate a sore throat
- keeping your head raised with extra pillows while you sleep, which can make breathing easier
- making sure you get enough rest
Contact your doctor for more advice on home remedies for a chest infection.
You should contact your doctor if you have a chest infection and any of the following apply:
- Your symptoms worsen rather than improve.
- You have a cough that lasts for more than 3 weeks.
- You cough up blood or mucus stained with blood.
- You have a weakened immune system.
- You have a long-term health condition, particularly if it affects your heart, kidneys, or lungs.
- You are pregnant.
- You are over the age of 65.
Your doctor can run tests to reach an accurate diagnosis and advise on suitable treatments.
Find out when to see a doctor for bronchitis.
If your doctor suspects a chest infection, they may take a full medical history and perform a physical examination. They may then order tests to confirm the diagnosis.
Possible tests include:
- blood tests or sputum tests to identify the type of infection
- chest X-ray to assess the inflammation in your lungs
- pulse oximetry, as conditions like pneumonia can prevent your lungs from moving enough oxygen around your bloodstream
Learn about what to expect with a chest X-ray.
Chest infections are a common condition that many people experience, particularly in the fall and winter months.
Certain factors can make you more likely to develop a serious chest infection. These include:
- being in certain age groups, particularly very young children and adults over 65
- being overweight
- being pregnant
- smoking
- having a weakened immune system
Various conditions also increase your risk of a serious chest infection, including:
- asthma
- chronic obstructive pulmonary disease (COPD)
- cystic fibrosis
- diabetes
- heart disease
- kidney disease
Contact your doctor if you have concerns about the risk factors for a serious chest infection.
You may develop complications from a serious chest infection. Complications are more likely in young children, older adults, and people with an existing health condition.
Pneumonia is a possible complication of bronchitis. According to the NHS, 1 in 20 cases of bronchitis will result in pneumonia.
Possible complications of pneumonia include:
- respiratory failure
- sepsis
- acute respiratory distress syndrome (ARDS)
- lung abscesses
You can take steps to reduce your risk of developing a chest infection. These include:
- regularly washing your hands
- avoiding smoking and secondhand smoke
- getting your recommended vaccines, such as the flu vaccine
If you have a chest infection, cover your mouth when you cough or sneeze. This can help prevent the spread of the infection.
- Acute vs. Chronic Bronchitis: What’s the Difference?
- Bronchitis Recovery: What to Expect
- Recovery from Pneumonia: What to Expect
- Warning Signs of Pneumonia
- Why Pneumonia Can Be Dangerous
A chest infection is an infection of the lungs. Some infections, such as bronchitis, affect the larger airways. Other infections, such as pneumonia, affect the air sacs in your lungs.
In most cases, you may be able to manage a chest infection with home remedies. However, your doctor may prescribe antibiotics if you have a serious bacterial infection.
Symptoms of a chest infection typically improve within 3 weeks. Contact your doctor if you still have a persistent cough after this time or if your symptoms worsen.