An Observational Study to Assess Respiratory Syncytial Virus (RSV) Respiratory Events Among Premature Infants

Inclusion Criteria: * Premature at birth (from 32 weeks and 0 days to 35 weeks and 6 days GA) * Age 6 months or less at the time of screening, and born in May 2009 through January 2010 for Season 1, or May 2010 through February 2011 for Season 2 * Written informed consent and any locally required authorization (eg, HIPAA), obtained from the subject's parent/or guardian prior to performing any protocol-related procedures. Exclusion Criteria: * Receipt of any RSV prophylactic agent: at any time prior to study participation * Participation in studies of investigational RSV prophylaxis or RSV therapeutic agents * Presence of bronchopulmonary dysplasia,hemodynamically significant congenital heart disease, congenital neuromuscular or congenital airway defects * Any condition that, in the opinion of the investigator, would limit life expectancy to less than 6 months