Viral pneumonia
Pneumonia - viral; Walking pneumonia - viralPneumonia is inflamed or swollen lung tissue due to infection with a germ.
Viral pneumonia is caused by a virus.
Causes
Viral pneumonia is more likely to occur in young children and older adults. This is because their bodies have a harder time fighting off the virus than people with a strong immune system.
Pneumonia
Pneumonia is a breathing (respiratory) condition in which there is an infection of the lung. This article covers community-acquired pneumonia (CAP). ...
Viral pneumonia is most often caused by one of several viruses:
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Respiratory syncytial virus (RSV)
Respiratory syncytial virus (RSV)
Respiratory syncytial virus (RSV) is a very common virus that leads to mild, cold-like symptoms in adults and older healthy children. It can be more...
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Parainfluenza virus
Parainfluenza virus
Parainfluenza refers to a group of viruses that lead to upper and lower respiratory infections.
Read Article Now Book Mark Article - Adenovirus (less common)
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Measles virus
Measles virus
Measles is a very contagious (easily spread) illness caused by a virus.
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Coronaviruses such as SARS-CoV-2, which causes COVID-19 pneumonia
Coronaviruses
Coronaviruses are a family of viruses. Infection with these viruses generally causes mild to moderate respiratory illnesses, such as the common cold...
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Coronavirus disease 2019 (COVID-19) is a respiratory illness that causes fever, coughing, and shortness of breath, but many other symptoms can occur....
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Serious viral pneumonia is more likely to happen in those with a weakened immune system, such as:
- Babies who are born too early.
- Children with heart and lung problems.
- People who have HIV/AIDS.
HIV/AIDS
Human immunodeficiency virus (HIV) is the virus that causes acquired immunodeficiency syndrome (AIDS). When a person becomes infected with HIV, the ...
Read Article Now Book Mark Article - People receiving chemotherapy for cancer, or other medicines that weaken the immune system.
Chemotherapy
The term chemotherapy is used to describe cancer-killing drugs. Chemotherapy may be used to:Cure the cancerShrink the cancerPrevent the cancer from ...
Read Article Now Book Mark Article - People who have had an organ transplant.
- Some viruses like the flu and SARS-CoV2 can lead to severe pneumonia in younger and otherwise healthy patients.
Flu
The flu (influenza) is a viral respiratory illness that causes fever, chills, runny nose, body aches, and cough. It spreads easily from person to pe...
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Symptoms
Symptoms of viral pneumonia often begin slowly and may not be severe at first.
The most common symptoms of pneumonia are:
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Cough (with some pneumonias you may cough up mucus, or even bloody mucus)
Cough
Coughing is an important way to keep your throat and airways clear. But too much coughing may mean you have a disease or disorder. Some coughs are d...
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Fever
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
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Chills
Chills refers to feeling cold after being in a cold environment. The word can also refer to an episode of shivering along with paleness and feeling ...
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Shortness of breath (may only occur when you exert yourself)
Shortness of breath
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
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Other symptoms include:
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Confusion, often in older people
Confusion
Confusion is the inability to think as clearly or quickly as you normally do. You may feel disoriented and have difficulty paying attention, remembe...
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Sweating
Sweating is the release of liquid from the body's sweat glands. This liquid contains salt. This process is also called perspiration. Sweating helps...
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Headache
Headache
A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are rare. Most people with headaches can feel much better...
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- Sharp or stabbing chest pain that gets worse when you breathe deeply or cough
Chest pain
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
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Fatigue
Fatigue
Fatigue is a feeling of weariness, tiredness, or lack of energy.
Exams and Tests
The health care provider will perform a physical exam and ask about the symptoms.
If the provider thinks you have pneumonia, you will also have a chest x-ray. This is because the physical exam may not be able to tell pneumonia from other respiratory infections.
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
Depending on how severe your symptoms are, other tests may be done, including:
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Complete blood count (CBC)
Complete blood count (CBC)
A complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...
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CT scan of the chest
CT scan of the chest
A chest CT (computed tomography) scan is an imaging method that uses x-rays to create cross-sectional pictures of the chest and upper abdomen....
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Blood cultures to check for viruses in the blood (or bacteria that might cause secondary infections)
Blood cultures
A blood culture is a laboratory test to check for bacteria or other germs in a blood sample.
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Bronchoscopy (rarely needed)
Bronchoscopy
Bronchoscopy is a test to view the airways and diagnose lung disease. It may also be used during the treatment of some lung conditions.
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Throat and nose swab tests to check for viruses such as the flu or SARS-CoV-2, the virus that causes COVID-19
Throat and nose swab tests
A throat swab culture is a laboratory test that is done to identify germs that may cause infection in the throat. It is most often used to diagnose ...
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Open lung biopsy (only done in very serious illnesses when the diagnosis cannot be made from other sources)
Open lung biopsy
An open lung biopsy is surgery to remove a small piece of tissue from the lung. The sample is then examined for cancer, infection, or lung disease....
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Sputum culture (to rule out other causes)
Sputum culture
Routine sputum culture is a laboratory test that looks for germs that cause infection. Sputum is the material that comes up from air passages when y...
Read Article Now Book Mark Article - Measuring levels of oxygen and carbon dioxide in the blood (arterial blood gases)
Levels of oxygen and carbon dioxide in ...
Blood gases are a measurement of how much oxygen and carbon dioxide are in your blood. They also determine the acidity (pH) of your blood.
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Treatment
Antibiotics do not treat this type of lung infection. Medicines that treat viral infections may work against some pneumonias caused by influenza, coronaviruses, and herpes viruses. These medicines may be tried if the infection is caught early.
Treatment may also involve:
- Corticosteroid medicines
- Increased fluids
- Oxygen
- Use of humidified air
A hospital stay may be needed if you are unable to drink enough and to help with breathing if oxygen levels are too low.
People are more likely to be admitted to the hospital if they:
- Are 65 years old or older
- Are children
- Are unable to care for themselves at home, eat, or drink
- Have another serious medical problem, such as a heart or kidney problem
- Have been taking antibiotics at home and are not getting better
- Have severe symptoms
However, many people can be treated at home. You can take these steps at home:
- Control your fever with aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen or naproxen), or acetaminophen. DO NOT give aspirin to children because it may cause a dangerous illness called Reye syndrome.
Reye syndrome
Reye syndrome is characterized by sudden (acute) brain damage and liver function problems. This condition does not have a known cause. This syndrome...
Read Article Now Book Mark Article - DO NOT take cough medicines without first talking to your provider. Cough medicines may make it harder for your body to cough up sputum.
- Drink plenty of fluids to help loosen secretions and bring up phlegm.
- Get a lot of rest. Have someone else do chores.
Outlook (Prognosis)
Most cases of viral pneumonia are mild and get better without treatment within 1 to 3 weeks. Some cases are more serious and require a hospital stay.
Possible Complications
More serious infections can result in respiratory failure, liver failure, and heart failure. Sometimes, bacterial infections occur during or just after viral pneumonia, which may lead to more serious forms of pneumonia.
Respiratory
The words "respiratory" and "respiration" refer to the lungs and breathing.
Heart failure
Heart failure is a condition in which the heart is no longer able to pump oxygen-rich blood to the rest of the body efficiently. This causes symptom...
When to Contact a Medical Professional
Contact your provider if symptoms of viral pneumonia develop or your condition gets worse after starting to improve.
Prevention
Wash your hands often, after blowing your nose, going to the bathroom, diapering a baby, and before eating or preparing food.
Avoid coming into contact with other sick patients.
DO NOT smoke. Tobacco damages your lungs' ability to ward off infection.
A medicine called palivizumab (Synagis) may be given to children under 24 months old to prevent serious RSV illness.
The flu vaccine, is given each year to prevent pneumonia caused by the flu virus. Those who are older and those with diabetes, asthma, chronic obstructive pulmonary disease (COPD), cancer, or weakened immune systems should be sure to get the flu vaccine.
Flu vaccine
All content below is taken in its entirety from the CDC Inactivated Influenza Vaccine Information Statement (VIS) www. cdc. gov/vaccines/hcp/vis/vis-...
Diabetes
Diabetes is a long-term (chronic) disease in which the body cannot regulate the amount of sugar in the blood.
Asthma
Asthma is a chronic disease that causes the airways of the lungs to swell and narrow. It leads to breathing difficulty such as wheezing, shortness o...
Chronic obstructive pulmonary disease (...
Chronic obstructive pulmonary disease (COPD) is a common lung disease. Having COPD makes it hard to breathe. There are two main forms of COPD:Chroni...
Cancer
Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.
The COVID-19 vaccine may help prevent severe pneumonia caused by the SARS-CoV-2 virus. It is particularly important for people with weakened immune systems, chronic health conditions, and older adults.
COVID-19 vaccine
COVID-19 vaccines are used to prepare the body's immune system to protect against COVID-19. Everyone ages 6 months and older should get a 2024-2025 C...
If your immune system is weak, stay away from crowds. Ask visitors who have a cold to wear a mask and wash their hands.
References
Daly JS, Ellison RT. Acute pneumonia. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 67.
Fung M, Babik JM, Munger JS, Kaufman DA. COVID-19. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray & Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 46a.
McCullers JA. Influenza viruses. In: Cherry JD, Harrison GJ, Kaplan SL, Steinbach WJ, Hotez PJ, eds. Feigin and Cherry's Textbook of Pediatric Infectious Diseases. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 178.
Musher DM. Overview of pneumonia. In: Goldman L, Schafer AI eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020;chap 91.
Schmitt ER. Pediatric lung disease. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 164.
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Pneumonia
Animation
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Lungs - illustration
The major features of the lungs include the bronchi, the bronchioles and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.
Lungs
illustration
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Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
-
Lungs - illustration
The major features of the lungs include the bronchi, the bronchioles and the alveoli. The alveoli are the microscopic blood vessel-lined sacks in which oxygen and carbon dioxide gas are exchanged.
Lungs
illustration
-
Respiratory system - illustration
Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.
Respiratory system
illustration
Review Date: 7/31/2022
Reviewed By: Denis Hadjiliadis, MD, MHS, Paul F. Harron Jr. Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.