RSV-Seropositive Children:
Inclusion Criteria:
- Greater than or equal to 12 months of age and less than 60 months of age
- Received routine immunizations appropriate for age
- Serum RSV neutralizing antibody titer greater than or equal to 1:40
- Serum RSV neutralizing antibody result obtained this calendar year
- Pre-inoculation serum RSV neutralizing antibody specimen obtained less than or equal to 56 days prior to inoculation
- Parent/guardian has completed the study comprehension assessment
- Parent/guardian has signed the study informed consent document (ICD)
- Subject is expected to be available for the duration of the study
Exclusion Criteria:
- Evidence of chronic disease
- Within the past 6 months had a decline in height or weight growth that crosses two major growth percentiles (e.g., from above the 75th to below the 25th)
- Known or suspected impairment of immune function
- Maternal history of positive HIV test
- Bone marrow/solid organ transplant recipient
- Major congenital malformations, including congenital cleft palate or cytogenetic abnormalities
- Current or unresolved suspected or documented developmental disorder, delay, or other developmental problem
- Cardiac abnormality requiring treatment
- Lung disease or reactive airway disease
- More than one episode of wheezing in the first year of life
- Wheezing episode or received bronchodilator therapy within the past 12 months
- Previous immunization with an experimental RSV vaccine
- Previous receipt or planned administration of anti-RSV antibody product
- Previous serious vaccine-associated AE or anaphylactic reaction
- Known hypersensitivity to any vaccine component
- Previous receipt of immunoglobulin or any antibody products
- Previous receipt of any other blood products within the past 6 months
- Member of a household that contains an infant who is less than 12 months of age during study days 0 to 10
- Member of a household that includes an immunocompromised individual
- Member of a household that includes a person who has received chemotherapy within the past 12 months
- Will attend a daycare facility that does not separate children by age and contains an infant who is greater than 12 months of age during study days 0 to 10
RSV-Seronegative Infants and Children:
Inclusion Criteria:
- Greater than or equal to 6 months of age and less than 25 months of age
- Received routine immunizations appropriate for age
- Serum RSV neutralizing antibody titer is less than 1:40
- Screening and pre-inoculation serum RSV neutralizing antibody specimen obtained less than or equal to 42 days prior to inoculation
- Parent/guardian has completed the study comprehension assessment
- Parent/guardian has signed the study ICD
- Subject is expected to be available for the duration of the study
- Born at greater than or equal to 37 weeks gestation or is currently greater than 1 year of age
Exclusion Criteria:
- Evidence of chronic disease
- Within the past 6 months had a decline in height or weight growth that crosses two major growth percentiles (e.g., from above the 75th to below the 25th)
- Known or suspected impairment of immune function
- Maternal history of positive HIV test
- Bone marrow/solid organ transplant recipient
- Major congenital malformations, including congenital cleft palate or cytogenetic abnormalities
- Current or unresolved suspected or documented developmental disorder, delay, or other developmental problem
- Cardiac abnormality requiring treatment
- Lung disease or reactive airway disease
- More than one episode of wheezing in the first year of life
- Wheezing episode or received bronchodilator therapy within the past 12 months
- Previous immunization with an experimental RSV vaccine
- Previous receipt or planned administration of anti-RSV antibody product
- Previous receipt of immunoglobulin or any antibody products
- Previous receipt of any other blood products within the past 6 months
- Previous serious vaccine-associated AE or anaphylactic reaction
- Known hypersensitivity to any vaccine component
- Member of a household which contains an infant who is less than 6 months of age during study days 0 to 28
- Member of a household that includes an immunocompromised individual
- Member of a household that includes a person who has received chemotherapy within the past 12 months
- Will attend a daycare facility that does not separate children by age and contains an infant who is less than 6 months of age during study days 0 to 28
Temporary Exclusion Criteria for RSV-Seropositive and RSV-Seronegative Children:
To be eligible to participate, RSV-seropositive and RSV-seronegative infants and children must satisfy none of the temporary exclusion criteria. The following conditions are temporary or self-limiting. Once the condition is resolved and the subject is otherwise eligible, the subject may be enrolled or rescreened, if necessary.
Any of the following events at the time of inoculation:
- fever (rectal temperature of greater than or equal to 100.4°F),
- upper respiratory signs or symptoms (rhinorrhea, cough, or pharyngitis)
- nasal congestion significant enough to interfere with successful inoculation
- otitis media
Receipt of any killed vaccine or live-attenuated rotavirus vaccine less than 14 days prior to inoculation
Receipt of the following medications less than 28 days prior to inoculation:
- any live vaccine other than rotavirus
- another investigational vaccine or investigational drug,
- systemic corticosteroids administered for greater than 14 days at a dosage equivalent to prednisone at greater than 2 mg/kg or 20 mg daily
- salicylate (aspirin) or salicylate-containing products
Receipt of a non-permitted concomitant medication or any of the following medications less than 3 days prior to inoculation:
- systemic antibacterial, antiviral, antifungal, anti-parasitic, or antituberculous agents, whether for treatment or prophylaxis,
- intranasal medications
Scheduled administration of the following in relation to planned inoculation:
- killed vaccine within the 14 days following,
- any live vaccine other than rotavirus within the 28 days following,
- another investigational vaccine or drug within the 28 days following for RSV-seropositive children and the 56 days following for RSV-seronegative infants and children