Viral pneumonia is an inflammation (irritation and swelling) of the lungs caused by infection with a virus. See also respiratory syncytial virus (RSV) and influenza.

Pneumonia is an infection of the lung that affects 1 out of 100 people annually. Viral pneumonia is caused by one of several viruses, including influenza, parainfluenza, adenovirus, rhinovirus, herpes simplex virus, respiratory syncytial virus, hantavirus, and cytomegalovirus.

Most cases of viral pneumonia are mild and get better without treatment, but some cases are more serious and require hospitalization. People at risk for more serious viral pneumonia typically have impaired immune systems such as people with HIV, transplant patients, young children (especially those with heart defects), the elderly, and people taking medications to suppress their immune systems in the treatment of autoimmune disorders.

• Cough
• Headache
• Muscular stiffness and aching
• Shortness of breath
• Fever
• Chills
• Sweating
• Fatigue
• Sore throat

• Clammy skin
• Nausea and vomiting
• Joint stiffness

• Sputum culture
• Blood tests for antibodies to specific viruses
• Chest x-ray
• Bronchoscopy
• Open lung biopsy (only done in very serious illnesses when the diagnosis cannot be made from other sources)

Antibiotics are not effective in treating viral pneumonia. Some of the more serious forms can be treated with antiviral medications. Other supportive care for viral pneumonia includes use of humidified air, increased fluids, and oxygen.. Hospitalization may be necessary to prevent dehydration and to help with breathing if the infection is serious.

Most episodes of viral pneumonia improve without treatment within 1-3 weeks, but some episodes last longer and cause more serious symptoms requiring hospitalization.

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.

Call your health care provider if symptoms of viral pneumonia develop.

Vaccines are available for influenza virus and respiratory syncytial virus for people at high risk of these forms of viral pneumonia.

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