Viral Etiologies of Infant Bronchiolitis, Croup and Upper Respiratory Illness During 4 Consecutive Years

Abstract

Background Prospective data on viral etiology and clinical characteristics of bronchiolitis and upper respiratory illness in infants is limited. Methods This prospective cohort enrolled previously healthy term infants during inpatient or outpatient visits for acute upper respiratory illness (URI) or bronchiolitis during September - May 2004–2008. Illness severity was determined using an ordinal bronchiolitis severity score. Common respiratory viruses were identified by real-time RT-PCR. Results Of 648 infants, 67% were enrolled during inpatient visits and 33% during outpatient visits. Seventy percent had bronchiolitis, 3% croup, and 27% URI. Among infants with bronchiolitis, 76% had RSV, 18% HRV, 10% influenza, 2% coronavirus, 3% HMPV, and 1% PIV. Among infants with croup, 39% had HRV, 28% PIV, 28% RSV, 11% influenza, 6% coronavirus, and none HMPV. Among infants with URI, 46% had HRV, 14% RSV, 12% influenza, 7% coronavirus, 6% PIV, and 4% HMPV. Individual viruses exhibited distinct seasonal, demographic, and clinical expression. Conclusions The most common infections among infants seeking care in unscheduled medical visits for URI or bronchiolitis were RSV and HRV. Demographic differences were observed between patients with different viruses, suggesting that host and viral factors play a role in phenotypic expression of viral illness.

Rhinovirus Detection in Symptomatic and Asymptomatic Children: Value of Host Transcriptome Analysis

“…However, the significance of RV detection in asymptomatic children and whether RV induces a detectable systemic host immune response remains unclear. In children, RVs are the most commonly detected respiratory viruses during symptomatic respiratory infections, including asthma exacerbations (34,35), but they are also the most common respiratory viruses identified in the absence of symptoms (8)(9)(10)(11)(12)(13). The rates of RV detection during symptomatic infection vary by condition.…”

What We Have Learned from the Influenza A pH1N1 2009/10 Pandemic: High Clinical Impact of Human Metapneumovirus and Respiratory Syncytial Virus in Hospitalized Pediatric Patients

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Are cytokines and cortisol important predictors for the severity of pediatric croup: A case control study

“…Interestingly, in our study, the most frequent etiological agent was detected as rhinovirus, and the second frequent was detected as parainfluenza virus. In a study conducted by Miller et al 18 . assessing viral etiological agents, the most frequent etiological agent was also detected as rhinovirus, and the second frequent was also detected as parainfluenza virus.…”