Bronchiolitis is a relatively common respiratory condition seen in children younger than 2 years old. According to a recent study out of Finland published in the Scandanavian journal Acta Paediatrica, bronchiolitis is a major cause of lower respiratory tract illness and hospitalization in babies, especially those younger than 6 months old. The condition is mostly caused by the respiratory syncytial virus (RSV), which is the infectious agent in over 75% of cases. Other viruses, including influenza (flu) and adenovirus represent the remaining 25% and in many cases exist as co-infections.
RSV season typically begins in October and ends in April. The virus is spread via the hands of caregivers and other inanimate surfaces (fomites), and can stay alive on them for several hours. The virus enters the respiratory tract and infiltrates the top cell layer of the lungs, known as bronchiolar epithelium, causing inflammation and swelling and obstructing the small airways. Once this happens, air passing through these small spaces emits a whistle-like sound that can be heard as a wheeze outside of the body.
This wheeze, along with a runny nose (rhinitis), cough, and fever, is suggestive of RSV bronchiolitis. It is important, however, for the pediatrician to rule out other disease processes, such as pneumonia or foreign body aspiration. Studies have shown that infants <12 weeks old, particularly those who were premature at birth, have an increased risk of requiring hospitalization and medical intervention. For many babies, though, this disease is self-limiting and no tests or treatments are necessary.
There are established risk factors for RSV that you can’t avoid; childcare attendance, school aged siblings, prematurity, congenital cardiopulmonary disease and immunodeficiency. But the steps listed below have been shown to reduce the risk of spreading RSV:
- When in a group setting such as daycare or doctors offices, be sure that you and others caring for your children decontaminate their hands with alcohol-based sanitizer before and after direct contact with children or inanimate objects
- Do not smoke tobacco or wear clothing that has been around cigarette smoke unless it has been thoroughly washed
- Avoid exposing your infant to air pollutants
- Always breastfeed your infant whenever possible to allow your infant's immune system to strengthen
- Always follow current vaccination guidelines, including the flu vaccine
Bronchiolitis. Dynamed Database. Updated 2014 May 12 02:17:00 PM. Accessed June 6 2014.
Pruikkonen H1, Uhari M, Dunder T, Pokka T, Renko M. Infants Under Six Months With Bronchiolitis Are Most Likely To Need Major Medical Interventions In The Five Days After Onset. Acta Paediatr. 2014 [Epub ahead of print]