Pneumonia is an infection of the lungs. Viruses, bacteria, and fungi can cause it. Pneumonia can cause the small air sacs in your lungs, known as alveoli, to fill with fluid.

Pneumonia can be a complication of COVID-19, the illness caused by the new coronavirus known as SARS-CoV-2.

In this article we’ll take a closer look at COVID-19 pneumonia, what makes it different, symptoms to watch out for, and how it’s treated.

Infection with SARS-CoV-2 begins when respiratory droplets containing the virus enter your upper respiratory tract. As the virus multiplies, the infection can progress to your lungs. When this happens, it’s possible to develop pneumonia.

But how does this actually happen? Typically, the oxygen you breathe into your lungs crosses into your bloodstream inside the alveoli, the small air sacs in your lungs. However, infection with SARS-CoV-2 can damage the alveoli and surrounding tissues.

Further, as your immune system fights the virus, inflammation can cause fluid and dead cells to build up in your lungs. These factors interfere with the transfer of oxygen, leading to symptoms like coughing and shortness of breath.

People with COVID-19 pneumonia can also go on to develop acute respiratory distress syndrome (ARDS), a progressive type of respiratory failure that occurs when the air sacs in the lungs fill up with fluid. This can make it hard to breathe.

Many people with ARDS need mechanical ventilation to help them breathe.

The symptoms of COVID-19 pneumonia may be similar to other types of viral pneumonia. Because of this, it can be difficult to tell what’s causing your condition without being tested for COVID-19 or other respiratory infections.

Research is underway to determine how COVID-19 pneumonia differs from other types of pneumonia. Information from these studies can potentially help in diagnosis and in furthering our understanding of how SARS-CoV-2 affects the lungs.

One study used CT scans and laboratory tests to compare the clinical features of COVID-19 pneumonia to other types of pneumonia. Researchers found that people with COVID-19 pneumonia were more likely to have:

  • pneumonia that affects both lungs as opposed to just one
  • lungs that had a characteristic “ground-glass” appearance via CT scan
  • abnormalities in some laboratory tests, particularly those assessing liver function

The symptoms of COVID-19 pneumonia are similar to the symptoms of other types of pneumonia and can include:

Most cases of COVID-19 involve mild to moderate symptoms. According to the Centers for Disease Control and Prevention (CDC), mild pneumonia may be present in some of these individuals.

However, sometimes COVID-19 is more serious. A large study from China found that about 14 percent of cases were severe, while 5 percent were classified as critical.

Individuals with severe cases of COVID-19 may experience more serious bouts of pneumonia. Symptoms may include trouble breathing and low oxygen levels. In critical cases, pneumonia can progress to ARDS.

When to seek emergency care

Be sure to seek emergency care immediately if you or someone else experiences:

Some people are at a higher risk for developing serious complications — like pneumonia and ARDS — due to COVID-19. Let’s explore this in more detail below.

Older adults

Adults ages 65 and older are at an increased risk for serious illness due to COVID-19.

Additionally, living in a long-term care facility, such as a nursing home or assisted living facility, can also put you at a higher risk.

Underlying health conditions

Individuals of any age who have underlying health conditions are at a higher risk for serious COVID-19 illness, including pneumonia. Health conditions that can put you at higher risk include:

Weakened immune system

Being immunocompromised can raise the risk of serious COVID-19 illness. Someone is said to be immunocompromised when their immune system is weaker than normal.

Having a weakened immune system can result from:

Diagnosis of COVID-19 is performed using a test that detects the presence of viral genetic material from a respiratory sample. This often involves collecting a sample by swabbing your nose or throat.

Imaging technology, such as a chest X-ray or CT scan, may also be used as part of the diagnostic process. This can help your doctor visualize changes in your lungs that may be due to COVID-19 pneumonia.

Laboratory tests may also be helpful in assessing disease severity. These involve collecting a blood sample from a vein or artery in your arm.

Some examples of tests that may be used include a complete blood count (CBC) and metabolic panel.

There’s currently no specific treatment that’s approved for COVID-19. However, a variety of drugs are being investigated as potential therapies.

Treatment of COVID-19 pneumonia focuses on supportive care. This involves easing your symptoms and making sure that you’re receiving enough oxygen.

People with COVID-19 pneumonia often receive oxygen therapy. Severe cases may require the use of a ventilator.

Sometimes people with viral pneumonia can also develop a secondary bacterial infection. If this occurs, antibiotics are used to treat the bacterial infection.

Lung damage due to COVID-19 may lead to lasting health effects.

One study found that 66 out of 70 people who had COVID-19 pneumonia still had lung lesions visible by CT scan when they left the hospital.

So, how can this affect your respiratory health? It’s possible that breathing difficulties may continue during and after recovery due to lung damage. If you have severe pneumonia or ARDS, you may have lasting lung scarring.

A recent study followed up on 71 individuals 15 years after they had SARS, which develops from a related coronavirus. The researchers found that lung lesions decreased significantly in the year after recovery. However, after this recovery period, the lesions plateaued.

While it may not always be possible to prevent COVID-19 pneumonia from developing, there are some steps you can take to lower your risk:

  • Continue to implement infection control measures, such as frequent handwashing, physical distancing, and regularly cleaning high-touch surfaces.
  • Practice lifestyle habits that can help boost your immune system, such as staying hydrated, eating a healthy diet, and getting enough sleep.
  • If you have an underlying health condition, continue to manage your condition and take all medications as directed.
  • If you do become ill with COVID-19, carefully monitor your symptoms and stay in touch with your healthcare provider. Don’t hesitate to seek emergency care if your symptoms begin to worsen.

While most cases of COVID-19 are mild, pneumonia is a potential complication. In very severe cases, COVID-19 pneumonia can lead to a progressive type of respiratory failure called ARDS.

The symptoms of COVID-19 pneumonia can be similar to other types of pneumonia. However, researchers have identified changes in the lungs that may point to COVID-19 pneumonia. These changes can be seen with CT imaging.

There’s no current treatment for COVID-19. People with COVID-19 pneumonia need supportive care to ease their symptoms and ensure that they’re receiving enough oxygen.

While you may not be able to prevent COVID-19 pneumonia from developing, there are steps you can take to lower your risk. This includes using infection control measures, managing any underlying health conditions, and monitoring your symptoms if you do get an infection with the new coronavirus.