The primary objective is to assess the burden of respiratory disease in outpatient settings among 32 to 35 weeks' gestational age (wGA) infants in the USA who did not receive RSV prophylaxis during the infants' first RSV season.

The primary objective is to determine the burden of RSV disease in outpatient settings among 32 to 35 wGA infants in the USA who did not receive RSV prophylaxis, as measured by rate of RSV-associated outpatient lower respiratory tract illness (LRI) during the infants' first RSV season.

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

Premature babies at birth - (32-35 WGA)