Azithromycin to Prevent Wheezing Following Severe Respiratory Syncytial Virus (RSV) Bronchiolitis

Inclusion criteria

• Age: 1-18 months.
• Hospitalization for the first episode of RSV bronchiolitis:

• Confirmed RSV infection by positive nasal swab results (viral culture and/or direct antigen detection) from the SLCH virology lab; AND
• At least two of the following symptoms/signs of bronchiolitis: respiratory rate greater than 40 breaths/minute; cough; wheezing; audible rales, crackles, and/or rhonchi; paradoxical chest movements (retractions).
• Duration of respiratory symptoms from initiation of symptoms to admission is 5 days or less. Time of admission will define by the time the child was seen in the ED for the visit that led to hospitalization.
• Randomization can be performed within 48 hours from time of admission (defined by time of first set of vital signs obtained on the floor).
• Willingness to provide informed consent by the child's parent or guardian

-

Exclusion criteria

• Prematurity (gestational age < 36 weeks).
• Presence or history of other significant disease (CNS, lung, cardiac, renal, GI, hepatic disease, hematologic, endocrine or immune disease). Children with atopic dermatitis will not be excluded from the study.
• Clinically significant gastroesophageal reflux currently treated with a daily anti-reflux medication (anti- H2 or PPI).
• The child has significant developmental delay/failure to thrive, defined as weight < 3% for age and gender.
• History of previous (before the current episode) wheeze or previous treatment with albuterol.
• Treatment (past of present) with corticosteroid (systemic or inhaled) and/or montelukast.
• Treatment with any antibiotics in the past 2 weeks.
• Treatment with Macrolide antibiotic (Azithromycin, clarithromycin or erythromycin) with the past 4 weeks.
• Current treatment with any daily medication (other then albuterol, vitamins or nutritional supplements).
• Participation in another clinical trial.
• Evidence that the family may be unreliable or nonadherent, or may move from the clinical center area before trial completion.
• Contraindication of use of azithromycin or any other macrolide antibiotics.