Symptoms of a Lung Infection

A lung infection can be caused by a virus, bacteria, and sometimes even a fungus.

One of the most common types of lung infections is called pneumonia. Pneumonia, which affects the smaller air sacs of the lungs, is most often caused by contagious bacteria, but can also be caused by a virus. A person becomes infected by breathing in the bacteria or virus after a nearby infected person sneezes or coughs.

How infections occur

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).

Symptoms

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:

• clear
• white
• green
• yellowish-grey

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:

• sweating
• chills
• muscle aches
• dehydration
• headache
• weakness

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.

Causes

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.