When the large bronchial tubes that carry air to and from your lungs become infected, it’s referred to as bronchitis. Bronchitis is more likely to be caused by a virus than by bacteria.

Viruses can also attack the lungs or the air passages that lead to the lungs. This is called bronchiolitis. Viral bronchiolitis most commonly occurs in infants.

Lung infections like pneumonia are usually mild, but they can be serious, especially for people with weakened immune systems or chronic conditions, such as chronic obstructive pulmonary disease (COPD).

Read on to learn the most common symptoms of a lung infection and what treatment you can expect if you have one.


The symptoms of a lung infection vary from mild to severe. This depends on several factors, including your age and overall health, and whether the infection is caused by a virus, bacteria, or fungus. Symptoms may be similar to those of a cold or flu, but they tend to last longer.

If you have a lung infection, here are the most common symptoms to expect:

1. Cough that produces thick mucus
Coughing helps to rid your body of the mucus produced from inflammation of the airways and lungs. This mucus may also contain blood.

With bronchitis or pneumonia, you may have a cough that produces thick mucus that may have a distinct color, including:

A cough can linger for several weeks even after other symptoms have improved.

2. Stabbing chest pains
Chest pain caused by a lung infection is often described as sharp or stabbing. The chest pain tends to worsen while coughing or breathing deeply. Sometimes the sharp pains can be felt in your mid to upper back.

3. Fever
A fever occurs as your body tries to fight off the infection. Normal body temperature is typically around 98.6°F (37°C).

If you have a bacterial lung infection, your fever may rise as high as a dangerous 105°F (40.5°C).

Any high fever above 102°F (38.9°C) often results in many other symptoms, such as:

muscle aches
You should see a doctor if your fever goes above 102°F (38.9°C) or if it lasts more than three days.

4. Body aches
Your muscles and back may ache when you have a lung infection. This is called myalgia. Sometimes you can develop inflammation in your muscles which can also lead to body aches when you have an infection.

5. Runny nose
A runny nose and other flu-like symptoms, such as sneezing, often accompany a lung infection like bronchitis.

6. Shortness of breath
Shortness of breath means that you feel like breathing is difficult or that you can’t breathe in completely. You should see a doctor right away if you’re having trouble breathing.

7. Fatigue
You’ll usually feel sluggish and tired as your body fights off an infection. Rest is crucial during this time.

8. Wheezing
When you exhale, you might hear a high-pitched whistling sound known as wheezing. This is the result narrowed airways or inflammation.

9. Bluish appearance of the skin or lips
Your lips or nails may start to appear slightly blue in color due to lack of oxygen.

10. Crackling or rattling sounds in the lungs
One of the telltale signs of a lung infection is a crackling sound in the base of the lungs, also known as bibasilar crackles. A doctor can hear these sounds using a tool called a stethoscope


Bronchitis, pneumonia, and bronchiolitis are three types of lung infections. They are typically caused by a virus or bacteria.

The most common microorganisms responsible for bronchitis include:

viruses such as the influenza virus or respiratory syncytial virus (RSV)
bacteria such as Mycoplasma pneumoniae, Chlamydia pneumoniae, and Bordetella pertussis
The most common microorganisms responsible for pneumonia include:

bacteria such as Streptococcus pneumonia (most common), Haemophilus influenzae, and Mycoplasma pneumoniae
viruses such as the influenza virus or RSV
Rarely, lung infections can be caused by fungi such as Pneumocystis jirovecii, Aspergillus, or Histoplasma capsulatum.

A fungal lung infection is more common in people who are immunosuppressed, either from certain types of cancer or HIV or from taking immunosuppressive medications.


A doctor will first take a medical history and ask about your symptoms. You may be asked questions about your occupation, recent travel, or exposure to animals. The doctor will measure your temperature and listen to your chest with a stethoscope to check for crackling sounds.

Other common ways to diagnose a lung infection include:

imaging, such as a chest X-ray or CT scan
spirometry, a tool that measures how much and how quickly you take in air with each breath
pulse oximetry to measure the level of oxygen in your blood
taking a sample of mucus or nasal discharge for further testing
throat swab
complete blood count (CBC)
blood culture


A bacterial infection usually requires antibiotics in order to clear it up. A fungal lung infection will require treatment with an antifungal medication, such as ketoconazole or voriconazole.

Antibiotics won’t work on viral infections. Most of the time, you’ll have to wait until your body fights off the infection on its own.

In the meantime, you can help your body fight off the infection and make yourself more comfortable with the following home care remedies:

take acetaminophen or ibuprofen to reduce your fever
drink lots of water
try hot tea with honey or ginger
gargle salt water
rest as much as possible
use a humidifier to create moisture in the air
take any prescribed antibiotic until it’s gone
For more severe lung infections, you may need to stay at a hospital during your recovery. During your stay, you may receive antibiotics, intravenous fluids, and respiratory therapy if you’re having difficulty breathing.

When to see a doctor

Lung infections can be serious if not treated. In general, see a doctor if your cough lasts more than three weeks, or you’re having trouble breathing. You can book an appointment with a doctor in your area using our Healthline FindCare tool.

A fever can mean different things depending on your age. In general, you should follow these guidelines:

See a doctor if your infant is:

younger than 3 months, with a temperature exceeding 100.4°F (38°C)
between 3 and 6 months, with a fever above 102°F (38.9°C) and seems unusually irritable, lethargic, or uncomfortable
between 6 and 24 months, with a fever over 102°F (38.9°C) for more than 24 hours
See a doctor if your child:

has a fever above 102.2°F (38.9°C)
is listless or irritable, vomits repeatedly, or has a severe headache
has had a fever for more than three days
has a serious medical illness or a compromised immune system
has recently been to a developing country
You should make an appointment to see a doctor if you:

have a body temperature over 103°F (39.4°C)
have had a fever for more than three days
have a serious medical illness or a compromised immune system
have recently been to a developing country
You should also seek emergency treatment at the nearest emergency room or call 911 if a fever is accompanied by any of the following symptoms:

mental confusion
trouble breathing
stiff neck
chest pain
persistent vomiting
unusual skin rash
inconsolable crying in children
If you have a weakened immune system and develop a fever, shortness of breath, or a cough that brings up blood, seek emergency medical care right away.