title: Relationship of early childhood viral exposures to respiratory symptoms, onset of possible asthma and atopy in high risk children: the Canadian Asthma Primary Prevention Study.
abstract: The contribution of respiratory viral infections to the onset of asthma and atopy is controversial. In "high risk" children (n = 455) born into asthmatic/atopic families, we determined the relationship of exposures to common respiratory viruses and concomitant respiratory symptoms, and to subsequent possible asthma and atopy at ages 1 and 2 years. Frozen nasal specimens, obtained when children were 2 weeks, 4, 8, and 12 months old, underwent reverse transcription-polymerase chain reaction (RT-PCR) testing for parainfluenza virus (PIV), respiratory syncytial virus (RSV), and picornavirus (rhinovirus/enterovirus). Odds ratios of viral RT-PCR results to respiratory symptoms ("cold," rhinitis, cough, wheezing) and to possible asthma or atopy at 1 and 2 years of age were calculated. Positive viral RT-PCR was associated with increased odds of "cold" and cough; PIV and picornavirus were associated with rhinitis, and RSV was associated with wheezing. PIV was associated with increased odds of atopy at 1 year of age in the control group; PIV and RSV were associated with possible asthma at 2 years of age. We conclude that in high-risk children, viral exposures documented by RT-PCR are associated with respiratory symptoms, and exposures to PIV and RSV during the first year of life are associated with the initial onset of possible asthma.
authors.affiliation: James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, Department of Pathology and Laboratory Medicine, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Kathy K
authors.initials: KK
authors.lastname: Lee
authors.forename: Richard G
authors.initials: RG
authors.lastname: Hegele
authors.forename: Jure
authors.initials: J
authors.lastname: Manfreda
authors.forename: Katherine
authors.initials: K
authors.lastname: Wooldrage
authors.forename: Allan B
authors.initials: AB
authors.lastname: Becker
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Ferguson
authors.forename: Helen
authors.initials: H
authors.lastname: Dimich-Ward
authors.forename: Wade T A
authors.initials: WT
authors.lastname: Watson
authors.forename: Moira
authors.initials: M
authors.lastname: Chan-Yeung
mesh_terms: D000367:Age Factors; D001249:Asthma / Q000209:etiology* / Q000821:virology*; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000209:etiology* / Q000821:virology*; D007223:Infant; D008297:Male; D010222:Parainfluenza Virus 1, Human; D010849:Picornaviridae; D018113:Respiratory Syncytial Virus, Human; D012141:Respiratory Tract Infections / Q000150:complications* / Q000821:virology*; D012307:Risk Factors