Respiratory Syncytial Virus (RSV)

Dr. Terry Murphy

ED Medical Director

Samaritan Hospital

Respiratory Syncytial Virus (RSV) is a very common RNA virus that typically causes mild respiratory symptoms in children and adults.  Almost all children are infected by two years of age.  RSV is also common in adults – it is estimated that three to seven percent of healthy adults and four to ten percent of high risk adults are infected annually.  Rarely, RSV will cause a more serious respiratory illness including severe breathing problems, apnea (cessation of breathing efforts) or pneumonia.  People at greatest risk for a more serious infection include premature infants, infants under 6 months of age or with underlying heart or lung illnesses, immunocompromised people of any age, people with asthma or COPD (chronic obstructive pulmonary disease), and, interestingly, people living at altitudes above 2500 feet.  It is estimated that RSV infection causes 120,000 pediatric hospitalizations, and 2700 adult and pediatric deaths per year in the U.S.

RSV spreads easily from person to person with the majority of infections spreading by contact, though the virus can also be passed by inhalation of mucous droplets in a cough or sneeze.  Infection by RSV does not confer future immunity and it is common to contract an illness from the RSV several times during your life. 

In children the most frequent manifestation of the infection is an illness physicians refer to as bronchiolitis.  The respiratory bronchioles are the smaller airway passages that are just before the alveoli (the part of the lung where oxygen and carbon dioxide are exchanged from capillaries).  The symptoms produced include a nasal discharge and swelling of the lining of the nasal passages (mucosal edema) which can occlude nasal passages; sore throat, cough, fever, and most prominently in children, difficulty breathing.  The difficulty breathing occurs because as the respiratory bronchioles are infected, similar to the nasal passages, there is both swelling (narrowing) of the inner lining and increased mucous production causing plugging of the narrow passageways.  Because of this narrowing and plugging of the bronchioles, the amount of effort needed to breathe air through these narrowed passageways into the lungs is greatly increased.  This extra effort at breathing becomes extremely fatiguing over time, especially for premature infants or newborns.  Additionally as the increased mucous is difficult to cough up, it acts as a great nidus (like a Petri dish) for bacteria to invade, proliferate and develop into pneumonia.

The usual length of symptoms in an uncomplicated infection in children is 10 -14 days, but as many as 20% of children can symptomatic for three weeks.  Children are “infectious” several days prior to the onset of symptoms, and up to several days after their symptoms abate.

It is easy to understand why the very young (fatigue), people who are chronically ill or immunocompromised (fatigue and pneumonia), and people with chronic respiratory illnesses such as asthma or COPD are at greater risk of morbidity or mortality.

While there is a specific anti-viral medication available for use (ribavirin); its use is generally restricted for very ill children who don’t respond to symptomatic therapy in the hospital.  For the majority of people, therapy aimed at reducing the swelling and reducing mucous production; clearing of retained mucous; and providing extra oxygen are the primary goals.  Potent hydrocortisone medications (corticosteroids), primarily when initiated early - before too much swelling has occurred, are often efficacious.  Likewise, the use of inhaled medication to widen the bronchioles (inhaled bronchodilators) such as albuterol or racemic epinephrine is a mainstay of treatment.

Most adults and children can be treated as outpatients without hospitalization.  However, those people in a high risk category may require hospitalization for continuous therapy with oxygen, inhaled bronchodilators, IV fluids to prevent or treat dehydration, and rarely assisted breathing with a ventilator.  Children or adults who appear fatigued or dehydrated, cannot maintain adequate oxygenation, appear toxic or having respiratory distress, or have other chronic illnesses are candidates for hospitalization.

Prevention of infection by RSV can be difficult because it is so common, especially during the fall, winter and early spring when there are frequent community “outbreaks.”  The primary tools of prevention are frequent hand washing and cleaning of surfaces where the virus may live for several hours; covering coughs and sneezes; and in general avoidance, to the extent possible, of people who are infectious.

This article is intended to provide useful information, not medical advice. This information cannot, and is not meant to, replace consultation with your physician regarding your individual circumstances.