Pneumonia is the medical term for lung inflammation. The condition typically occurs when a person acquires a viral, bacterial, or fungal lung infection.

Pneumonia usually triggers respiratory symptoms such as a cough. However, a person can have the condition without a cough. Those who do not experience this symptom are likely to experience other indications.

This article outlines the common and atypical signs and symptoms of pneumonia. We also list the different types of pneumonia and their causes, as well as information on treatments, prevention, and when to speak with a doctor.

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The signs and symptoms of pneumonia vary from person to person. Some people may experience a mild illness that clears up on its own. Others may have severe symptoms and life threatening health complications.

People with pneumonia typically develop a cough. However, the American Thoracic Society state that it is possible to have pneumonia without the symptom.

According to the National Heart, Lung, and Blood Institute, those most likely to develop complications of pneumonia also tend to experience the most atypical symptoms. These people include:

  • young children
  • older adults
  • people with serious underlying health conditions

The most common signs and symptoms of pneumonia include:

Pneumonia triggers irritation and inflammation of the tiny air sacs, known as alveoli, within the lungs. These air sacs are responsible for exchanging oxygen and carbon dioxide, enabling the body to carry out its vital functions.

Pneumonia can cause the alveoli to fill with fluid or pus. Coughing is a natural reflex that aims to remove these excess fluids from the airways. A cough may bring up a green, yellow, or bloody mucus.

Atypical signs and symptoms in adults

For older adults and people with underlying health conditions, a cough may not be the primary symptom of pneumonia. These people may instead experience atypical signs and symptoms, such as:

Signs and symptoms in babies

Babies with pneumonia may also not experience coughing. Instead, they may display the following signs and symptoms:

  • vomiting
  • tiredness
  • restlessness
  • grunting
  • flaring of the nostrils when breathing
  • pulling the muscles between the ribs inward when breathing
  • rapid breathing
  • bluish discoloration of the skin and lips in light-skinned people, though they may appear gray or whitish in those with dark skin

Doctors classify pneumonia according to its type, severity, and location.

Type of pneumonia

Below are the different types of pneumonia and their associated causes.

  • Viral pneumonia: Develops in response to contracting a viral infection of the lungs.
  • Bacterial pneumonia: Occurs due to acquiring a bacterial infection within the lungs.
  • Fungal pneumonia: Develops in response to contracting a fungal infection within the lungs. It is less common than other types of pneumonia.
  • Aspiration pneumonia: Develops following inhalation of fluid into the lungs. This type is more common among people with certain breathing or swallowing disorders.

How and where someone develops pneumonia, such as at the hospital, on dialysis, or in long term nursing care, helps doctors differentiate the cause of the infection and devise appropriate treatments.

Severity of pneumonia

Doctors sometimes classify pneumonia according to its severity.

Mild pneumonia is not life threatening. People with this condition can usually recover at home with little or no medical treatment.

Moderate pneumonia requires a hospital stay for supportive care.

Severe pneumonia means that the lungs are not taking in enough oxygen or that the infection risks damage to other organs. A person with this condition may require intravenous medications, as well as mechanical ventilation to assist their breathing.

Location of pneumonia

Pneumonia can affect one or both lungs. It can also affect different sections or “lobes” of the lung.

A chest X-ray or other medical imaging test can reveal the location and extent of the pneumonia.

The treatment for pneumonia depends on its cause and severity. Some options include:

  • antibiotics for bacterial pneumonia
  • antiviral medications for viral pneumonia
  • antifungal medications for fungal pneumonia
  • steroids to improve lung function in people with severe pneumonia
  • over-the-counter medications to ease pain and reduce fever
  • fluids to prevent dehydration

A person with severe pneumonia may need to stay in the hospital for monitoring, receiving intravenous fluids and medications, and assisted breathing. If the condition is life threatening, a surgeon may need to remove part of the lung with the infection.

Most people recover from pneumonia. However, those with risk factors for the condition are more likely to experience serious and potentially life threatening complications.

Some risk factors for pneumonia include:

Severe, untreated pneumonia can cause life threatening complications, such as:

  • damage to the lungs, heart, liver, or kidneys
  • sepsis
  • organ failure
  • death

The following strategies can reduce a person’s risk of developing pneumonia:

  • practicing frequent handwashing, especially before eating and after going out in public
  • adopting strategies to prevent the spread of COVID-19, such as wearing a mask or face-covering in public
  • avoiding going to school or work when sick
  • exercising regularly to keep the heart and lungs healthy
  • talking to a doctor about getting the pneumococcal vaccine, which reduces the risk of pneumococcal pneumonia
  • annual immunization against influenza
  • getting up to date vaccinations for pertussis, also known as whooping cough
  • stopping smoking or vaping

Pneumonia is a severe condition that requires prompt medical attention. Even if a person does not experience a cough, this does not rule out the possibility that they have moderate or severe pneumonia.

A person should call their doctor if:

  • they experience signs or symptoms of pneumonia, especially if they have a respiratory infection or have recently recovered from one
  • they are undergoing home treatment for pneumonia, and their symptoms suddenly worsen
  • they are caring for a child, baby, or older adult who shows typical or atypical signs or symptoms of pneumonia
  • they are caring for a person with dementia who suddenly develops worsening symptoms of confusion or disorientation

Anyone who experiences severe breathing difficulties should phone for an ambulance immediately.

Pneumonia is a respiratory condition involving inflammation of the air sacs within the lungs. The disease is usually caused by contracting a viral, bacterial, or fungal infection.

Symptoms of pneumonia differ from person to person. Most people will develop a dry or wet cough, but this is not always the case. Those who do not have a cough may experience other symptoms, such as a fever, nausea and vomiting, or weakness.

Without treatment, pneumonia can be life threatening. Anyone who experiences signs or symptoms of the condition should speak with a doctor for a diagnosis and appropriate treatment. People who develop severe breathing difficulties should seek emergency medical attention.