What is RSV?

Every year from November to April we are officially in RSV season. This may not mean much to you but for pediatricians this is something we brace for and dread. So why should you care? Typically an older child or adult infected with RSV will seem to just have a cold. However, if you have an infant or small child, RSV, respiratory syncytial virus, can be much more than just a cold.

Bronchiolitis

RSV, among other viruses, causes an infection known as bronchiolitis. Bronchiolitis is a nasty illness in which the small airways in the lungs, called bronchioles, get inflamed. The inflammation can block the airways, making it hard to breathe. In addition to inflammation, the infection causes copious amounts of mucous and secretions, which can also block the airway. So for small babies with small airways, this presents a real problem.

The typical presentation of bronchiolitis starts with cold symptoms; runny nose, fever and cough. About 2-3 days into the infection parents may notice their child breathing faster, using more energy to breathe, wheezing and even vomiting. Some babies feed poorly and develop dehydration.  In some cases, babies may present with apnea, which is when they stop breathing all together, even without any other sign of illness.

The diagnosis of bronchiolitis is made by your doctor after performing a history and physical exam. Typically blood tests, chest x-rays or other tests are not needed.

Risk Factors

Babies who were born prematurely are at particularly high risk for complications from RSV in the first year of life. This means they are more likely to develop severe lower respiratory tract disease requiring hospitalization. Also, children with congenital heart disease, chronic lung disease and immune deficiencies can develop more severe infection. Keep in mind that the majority of children that require hospitalization for RSV however, are full-term healthy infants. All parents of young infants need to be aware of its existence.

Treatment

Treating RSV is mostly supportive. The most important thing to do is clear mucous from the nose so babies can breathe and eat. For babies who aren’t feeding well, IV fluids may be needed if they become dehydrated. Oxygen may be needed for babies who have so much mucous build up that their oxygen level is low. Some babies may develop a secondary bacterial pneumonia or ear infection, both of which require antibiotics. However, there is not currently an anti-viral medication routinely used in otherwise healthy babies with RSV, and antibiotics are never indicated for viral infections. For high risk babies with chronic health conditions, hospitalization for close observation or other interventions may be needed.

Because the inflammation and mucous plugging causes wheezing, you may think that albuterol would work well like it does for asthma.  However, the mechanism of wheezing; mucous plugging in RSV v. airway constriction in asthma, is very different.  Studies have shown that any improvement in symptoms and oxygen levels from albuterol use is short lived in RSV patients.  Therefore, unless your child has underlying asthma, routine use of albuterol is not recommended.

Prevention

Currently there is no vaccine to prevent infection with RSV. There is, however, something called Synagis (palivizumab) which is a monoclonal antibody given to reduce the risk of serious lung disease (monoclonal antibodies are antibodies against the virus produced in the lab.)  It does not prevent infection all together. Furthermore, it has been shown in the past few years to have very little effect on wheezing, mortality and hospitalization. Therefore, the American Academy of Pediatrics has updated its recommendation to only use Synagis in babies with a gestational age of 29 weeks or younger or those with chronic lung disease or congenital heart disease. Synagis is also recommended for babies who require oxygen at home, those who are profoundly immunocompromised and those who have a neuromuscular disease that makes it hard to clear secretions.

The mainstay of prevention is to make sure everyone who spends time around babies is not sick, does not smoke, washes their hands regularly and covers their cough. Keep hand sanitizer available for all visitors can protect babies at home. Babies at risk for severe RSV infection should be kept out of large group child care as well.  There is also evidence that breastfed babies have lower rates of hospitalization from lower respiratory tract disease due to RSV.