RSV or Respiratory Syncytial Virus infection is a condition which is being recognized frequently, as we are able to identify the cause of many viral respiratory infections. Most people who catch RSV infections have what amounts to a deep “chest cold”. Most often, this illness could be simply described as the “common cold”. For most people, RSV infections are not at all serious and resolve without incident in about two weeks. Please see our handbook for advice regarding the treatment of colds.

Both adults and children can catch RSV infections. Each year, usually in the winter months, we have epidemics of RSV infections. In the United States there are usually about 3 million children who will get RSV infections annually. Because RSV infections do not cause life long immunity, you can catch RSV many times. The infection is very contagious. The usual story we get from patients is that “the whole house is sick” with a bad cold. The problem that RSV infection presents is that very young children less than 12 months old, children with medical problems such as prematurity and heart disease, and children with asthma who catch RSV can develop more severe breathing problems than just common cold symptoms with the development of breathing difficulty. This breathing difficulty is similar to what children with asthma experience during an asthma attack. Approximately 20% of children less than two years of age will develop wheezing with breathing difficulty when they are infected with RSV. In very rare cases, the breathing difficulty of RSV bronchiolitis can even progress to respiratory failure. Many people call this “viral bronchitis” or “viral pneumonia”. This condition has the medical name of “bronchiolitis”.  Thankfully, to lessen the burden of severe RSV infection in premature infants and infants with chronic medical conditions such as lung problems and heart problems, we now have a preventative treatment to help prevent severe disease due to RSV.

Other viruses besides RSV can cause bronchiolitis. Human metapneumovirus and para-influenza virus are examples of other viruses which can cause bronchiolitis. Because the symptoms, course and treatment of these viruses are the same as that of RSV, these will all be covered in this one section on bronchiolitis.

Symptoms of Bronchiolitis

For the 20% of children who catch RSV and then develop bronchiolitis, the symptoms have to do with inflammation of the smallest air passages of the lungs, the bronchioles. Just as a cold virus can make the nose become congested and filled with mucous, RSV infection in some children can “go down into the chest” and cause the bronchioles to become swollen, constricted, and filled with thick mucous. These factors cause the lungs to become stiff with obstruction to air flow which is especially seen when the child tries to exhale. The obstruction to airflow in the lungs causes the hallmark symptom of bronchiolitis, wheezing. Wheezing refers to the high pitched, or whistling sound that air makes when being forcibly pushed through swollen, constricted air passages.

In addition to wheezing, the swollen, constricted, mucous filled bronchioles cause a severe, wet sounding cough as the child tries to clear the thick mucous from the airways. Coughing is an important defense mechanism of the body in bronchiolitis which should not be interfered with because it protects against the development of bacterial pneumonia. Another symptom of bronchiolitis is rapid breathing. This is usually mild when the respiratory rate is 40 to 60 breaths taken every 60 seconds. Respiratory rates greater than 60 breaths per 60 seconds while the child is not active are more worrisome. This may indicate that the child is having difficulty getting enough air in and out of the lungs to meet the demands of the body. Often this type of respiratory distress is accompanied by retractions, which refers to sinking in of the skin between the ribs, near the collar bone and at the base of the neck which occurs with breathing. Another sign of a more serious problem with breathing is audible wheezing as the child exhales. Sometimes, with more severe distress, the child breathing can actually become quieter indicating less air movement. Rapid respirations above 60 breaths per minute accompanied by retractions and labored breathing in a child whose respirations are very quiet are not normal and are worrisome. You should seek medical attention in such circumstances.

Usual Course of Bronchiolitis

RSV bronchiolitis is a 14 day illness which like other viruses has a typical clinical course. After an incubation period of 4 to 7 days, the first symptom of RSV is a runny nose which is usually associated with fever. The runny nose is typically very bad with copious clear mucous running out of the nose. A cough then develops one to two days later, which is soon followed by wheezing and sometimes shortness of breath. Very young infants less than 6 months old who catch RSV are particularly prone to severe disease and apnea (stopping breathing).

The following graph shows the expected time course and symptoms of RSV.

  • Runny Nose                    X   X   X   X   X   X   X   X    x    x
  • Fever                                      X   X   X   X   X   X
  • Cough                                                 X   X   X   X   X   X    X    X    x    x
  • Wheezing                                                 X   X   X   X   X    X    x    x
  • Apnea                                                             X   X   X
  • Hospitalization                                            X   X   X   X   X   X   X
  • Contagious               X   X   X   X   X   X   X   X   X   X    X    x   x    x
  • Days of illness          0   1    2    3   4    5    6    7   8    9   10  11  12  13  14

As seen by the graph above, RSV takes several days to develop. The course of RSV is predictable, it gets worse for several days then gradually gets better. Like other viral  infections, it is impossible to effectively treat bronchiolitis to prevent severe disease. The disease is going to run its course despite our best efforts. Therefore, even if parents seek prompt medical attention at the beginning of an RSV illness with the initiation of appropriate treatment, the child may worsen despite that treatment, and require hospitalization. Of the 3 million children who contract RSV each year in the US about 2% will require hospitalization.


The treatment of RSV depends on the severity of the illness. Children who have only nasal congestion and cough without breathing difficulty require only “common cold” treatment as described in this handbook (please refer to this). Again, 80% of children who catch RSV will fall into this category.

Children who have mild wheezing should be seen in the office for an appointment during regular office hours. In years past, it was usual practice to treat children with wheezing with an inhaled asthma medication called albuterol.  This medication is a derivative of adrenaline which opens the lungs by helping to relax the airways which are constricted. For many years, this medication was a mainstay in the treatment of bronchiolitis.  In recent years however, multiple studies have shown that Albuterol really doesn’t improve this disease in most children.  Children with RSV infection will usually get over bronchiolitis on their own without treatment.  Therefore, the American Academy of pediatrics has issued a practice guideline which states that most children with bronchiolitis do not need inhaled albuterol, chest x-rays nor RSV tests.  Watchful waiting is needed.  The AAP does recommend that children with bronchiolitis have oxygen saturation testing (pulse ox) to insure that supplemental oxygen is not needed.  Sometimes, we do give a trial of albuterol inhalation in the office to determine if it is helpful.  It if is, we may prescribe this for your child.

If inhaled albuterol is given to your child, this medication may cause tremors, agitation, hyperactivity and insomnia. Only if these become severe, are they worrisome. Mild wheezing is not serious, as long as the child is taking adequate fluid and is playful and alert.

Similarly, we treat more severe RSV infections in the same manner.  A trial of albuterol may be given and a pulse ox is usually performed.  There are other respiratory treatments that are also available if your child is more severely affected. We will choose the most appropriate medication for you during your office visit.  Office visits are needed for children with wheezing and any sign of respiratory distress.

Other things you can do at home include:

  • Give plenty of fluids.
  • Use a humidifier. Humidity helps to loosen thick secretions so that they can be coughed up.
  • Do not smoke around your child with bronchiolitis. This is extremely harmful and may well cause your child to develop respiratory failure.
  • In young children, suction the nose to remove mucous. You should use saline drops with this. Please see the section on “common cold” on how to do this.  Antibiotics do not help RSV infection because it is a viral illness and antibiotics do not treat viruses. Ear infections are common with RSV occurring in 20 to 30 % of the cases. You should know however, that the antibiotics while helping the ear infection will do nothing for the RSV infection.

Contact us within 24 hours if the following occur:

  • Your child does not take enough fluids in and begins to show early signs of dehydration (see the Parents Medical Handbook for a description of the signs of dehydration).
  • Your child develops an earache.
  • Your child develops difficulty sleeping, but is OK otherwise.
  • More severe breathing problems are much more worrisome. You should contact us immediately if:
  • Your child develops labored or difficult breathing.
  • Your child develops rapid breathing faster than 60 breaths per 60 seconds while your child is quiet.
  • Your child develops significant retractions (sinking in of the skin between the ribs, near the collar bone and at the base of the neck which occurs with breathing)
  • Your child’s wheezing worsens.
  • Your child stops breathing or passes out.
  • Your child appears to be sicker and not doing well.
  • Your child develops a blue color of the lips and the area around the lips.
  • Other information: Your child is contagious for two weeks from the beginning of the illness. Usually the illness is thought to be noncontagious when the wheezing disappears. The illness is spread by direct contact with infected nasal secretions. Therefore, avoidance of infected nasal secretions is important. Hand-washing is an effective tool at preventing the spread of RSV as is avoiding being around someone with RSV.  Lastly, the cough of RSV bronchiolitis can last for a month.

Prescription treatment of RSV Bronchiolitis may include the following if they are found to be helpful:

  • Albuterol MDI, 2 to 4 puffs every 4 to 6 hours as needed for wheezing. This medication my cause tremors, agitations, nervousness and insomnia. Only if these become severe are they a cause for concern.
  • Albuterol inhalent solution with a nebulizer.
  • Xopenex inhalant solution with a nebulizer.

An AeroChamber with mask may be prescribed to use with an albuterol metered dose inhaler.  This type of spacer is for the child who is too young to always be able to breathe in through his/her mouth at the right time. Usually this is someone 6 years of age or under or who is unable to use a mouthpiece for another reason. Here is how to use a Metered-Dose Inhaler with an AeroChamber® with Mask:

  1. Remove the plastic protective cap from the MDI.
  2. Insert the metered dose inhaler (MDI) into the plastic holder on the rubber end of the AeroChamber®.
  3. Shake the AeroChamber® and the MDI.
  4. Sit the child on your lap. The back of your child’s head should be against your chest.
  5. Apply the mask to your child’s face so that the nose and mouth are covered.
  6. Spray 1 puff from the metered-dose inhaler into the AeroChamber®.
  7. Keep the mask in place for 6 breaths. Have your child breathe through his/her mouth, if possible. Watch the child’s chest to count breaths. If your child objects to the treatment and cries, this only increases how deeply your child is breathing. This will actually help deposit the medication deeper into the lungs. So, don’t let the objections of your child stop you from giving him or her the needed treatment.
  8. Rest and repeat according to the our directions.
  9. At least once a week, take the AeroChamber® end off and rinse with warm tap water.
Reviewed by Dr. Byrum 2/16/2020