In the preliminary stages, viral pneumonia does not produce any serious symptoms. As the disease progresses and treatment is delayed, the condition may present itself with more severe symptoms. The following are the signs and symptoms of viral pneumonia:

• Dyspnea
• Fever, mild to high
• Coughing up mucus
• Running nose
• Headache
• Confusion
• Fatigue
• Loss of appetite
• Excessive sweat
• Clammy skin
• Sharp pain in the chest during coughing or breathing
• Myalgia
• Chills
• Cyanosis

To begin with, a thorough lung examination is done to diagnose the condition. If a wheezing sound is heard from the lungs then further confirmatory tests are carried out.

• Chest x-ray would demonstrate bilateral lung involvement, if virus is the cause of pneumonia.
• CT scan of the chest
• Specific viral serologic tests [9]
• Blood tests to get complete blood count
• Sputum culture
• Blood cultures to identify the type of virus involved
• Nasal swab test

When the above mentioned diagnostic procedures draw a non–specific conclusion, then open lung biopsy is the only available method for detecting the disease.

As the disease is caused through viral agents, antibiotics would be of no help to treat infection. Instead, anti-viral agents are prescribed to rid the body from the viruses.The various types of anti-viral medications include rimantadine, zanamivir, amantadine, cidofovir, foscarnet, ribavirin, ganciclovir, acyclovir and oseltamivir. The other modes of treatment involved to ease the symptoms include:

• Administration of fluids
• Oxygen for helping the individuals breathe
• Corticosteroid medications
• Management of symptoms using humidified air

In case of serious infections, the individuals may require a hospital stay.

Prognosis of viral pneumonia depends on the type and extent of severity of the disease. Individuals who have developed mild pneumonia tend to get better with treatment within 1 to 3 weeks. However, those develop acute bronchitis require hospitalization and suffer from serious complications.

Complications

Infections are the most serious complication of viral pneumonia. It can lead to the following conditions:

• Respiratory failure
• Heart failure
• Liver failure
• Chronic obstructive pulmonary disease (COPD) [8]

In many cases, affected individuals suffer from infections after an attack of viral pneumonia which in turn can lead to development of severe complications.

Infections due to viruses are the obvious cause of viral pneumonia. The following are the common types of viral agents that are known to cause pneumonia:

• Adenovirus
• Parainfluenza virus
• Influenza virus
• Syncytial virus
• Coronavirus
• Arbovirus
• Measles virus
• Rotavirus
• Polyomavirus
• Respiratory syncytial virus
• Human Metapneumovirus (hMPV) [2]

Children with a weak immune system or those with heart and lung diseases are more prone to contract viral pneumonia.

Viral pneumonia is a common problem affecting more commonly the children and the immune-compromised population [3]. According to the statistical reports provided by National Center for Health Statistics, viral pneumonia is ranked 8th as the leading cause of death in the United States. It has also been estimated that as high as 200 million individuals (100 million children + 100 million adults) fall prey to viral pneumonia each year.

Elderly patients are more prone to viral pneumonia because of inefficient mucus expectoration due to decreased respiratory muscle strength [4].

For an infection to take place, the causative agent must enter the human system. In this case, viruses are the agents that gain entry into the respiratory system through inhalation either via the mouth or nose. The viruses then multiply in the epithelial lining of the lungs causing inflammation which in turn blocks the oxygen flow giving rise to breathing problems.

The extent of damage depends on the type of virus that has attacked the system. It is very common for viral pneumonia to coexist with a bacterial pneumonia making diagnosis difficult by clinical means only [5]. Certain types only damage the bronchial cells while other types may directly affect the immune system [6]. Pulmonary alveolar damage in viral pneumonia may result in bloody effusion due to diffuse alveolar damage [7].

There are several preventive measures that need to be followed to keep pneumonia viruses at bay:

• Hands should be washed after blowing nose, before preparing and eating food, after diapering baby and after using washroom.
• It is also necessary to vaccinate children against pneumonia. This acts as a preventive measure against pneumonia virus. In addition, the elderly population and individuals with chronic disease conditions should also receive vaccination.
• The drug palivizumab and ribavirin is given to children under the age of 2 years to protect them against respiratory syncytial virus [10].
• Children must receive the flu vaccine every year to protect them against the influenza virus.
• Individuals with a suppressed immune system are required to avoid crowded places and adopt safety measures when meeting people suffering from cough and cold.

Viral pneumonia is the infection of the lungs caused due to viral agents. Viruses are second most common cause of pneumonia in children and adults [1]. Such a condition is usually mild and does not cause any serious complications unless it affects the geriatric and the immunecompromised population. In such individuals, viral pneumonia may present serious complications such as severe hypoxemia and respiratory failure.

Recent research reports point towards the fact that viruses account for more than 50% cases of acquired pneumonia. The rest of the cases are caused either by bacteria or parasites.

Definition

Viral pneumonia is characterized by infection of the lungs due to viruses. It is a less serious condition than bacterial pneumonia, but can present life threatening complications in elderly population, immune compromised individuals and pregnant women.

Cause

Several types of viruses such as respiratory syncytial virus, influenza, parainfluenza, rotavirus, adenovirus, measles virus, rubella virus and cytomegalovirus are known to cause viral pneumonia.

Symptoms

Symptoms of viral pneumonia include fever, shortness of breath, shaking chills, fatigue, weakness, loss of energy, lips develop bluish, productive cough, running nose, headache and muscle ache.

Diagnosis

Preliminary physical examination of the lungs if reveal a wheezing sound indicate viral pneumonia. In addition, X-ray and CT scan of the chest, followed by blood test and blood cultures also form an important part of the diagnosis of the condition. In rare cases open lung biopsy may also be required when all other procedures fail to diagnose the condition.

Treatment

Individuals with viral pneumonia are given anti-viral agents for treating the infections. In serious conditions, hospitalization would be required to manage the symptoms. Humidified air, fluid replacement, oxygen and corticosteroid medications form the basis of the treatment regime.

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