Respiratory Syncytial VirusesRespiratory Tract InfectionsRespiratory Syncytial Virus InfectionsRespiratory Syncytial Virus, HumanRespiratory Syncytial Virus, BovineRespiratory Syncytial Virus VaccinesRespirovirus InfectionsBronchiolitis, ViralUrinary Tract InfectionsBronchiolitisParamyxoviridae InfectionsMetapneumovirusNasopharynxPneumonia, ViralVirus DiseasesRespiratory SystemHN ProteinAnti-Bacterial AgentsBronchitisSigmodontinaePneumoniaAcute DiseaseCommunity-Acquired InfectionsParainfluenza Virus 3, HumanInfant, NewbornViral Fusion ProteinsMoraxella (Branhamella) catarrhalisLungRespiratory SoundsSeasonsPneumonia, BacterialVirusesAntibodies, ViralHuman bocavirusBocavirusPicornaviridae InfectionsHospitalizationRespiratory Tract DiseasesRhinovirusViral ProteinsBacterial InfectionsHaemophilus influenzaeBronchopneumoniaParvovirinaeProspective StudiesParainfluenza Virus 2, HumanAntigens, ViralStreptococcus pneumoniaeVirus ReplicationCoughCroupParvoviridae InfectionsAntiviral AgentsNasal Lavage FluidAmoxicillin-Potassium Clavulanate CombinationCommon ColdMice, Inbred BALB CBronchoalveolar Lavage FluidViral Envelope ProteinsParainfluenza Virus 1, HumanHaemophilus InfectionsNeisseriaceae InfectionsSputumDrug UtilizationNasal MucosaInfluenza, HumanMycoplasma pneumoniaeRespirovirusVirus CultivationMolecular Sequence DataRNA VirusesRNA, ViralCalcitoninNeutralization TestsPneumonia, PneumococcalCell LinePhysician's Practice PatternsVaccinia virusPolymerase Chain ReactionPneumococcal InfectionsOrthomyxoviridaeVirologyAnti-Infective AgentsSensitivity and SpecificityMoraxellaceae InfectionsFluorescent Antibody Technique, DirectImmunocompromised HostVirus SheddingClavulanic AcidsTime FactorsViral VaccinesParainfluenza Virus 3, BovineOtitis MediaNoseTracheitisAzithromycinRisk FactorsVero CellsAsthmaBodily Secretions