Familial asthma risk and infant respiratory infection etiology and severity
Published Online: February 16, 2012
Respiratory syncytial virus (RSV) and human rhinovirus (HRV) are the most common viruses associated with infant acute respiratory infections (ARI). Both RSV and HRV lower respiratory tract infections (LRTIs) during infancy and early childhood are associated with an increased risk of asthma later in childhood. However, the risk for developing asthma is higher among children who had an HRV LRTI compared with RSV LRTI. Whether LRTI with either RSV or RV reflects a familial predisposition to develop asthma, or is causal, has been a subject of much debate. One approach to this question is to determine the relationship between an infant’s familial predisposition to develop asthma and the viral etiology and/or severity of symptomatic infant ARIs.
In an original research article submitted to The Journal of Allergy & Clinical Immunology (JACI), Carroll et al. tested the hypothesis that infants who had a mother with asthma would have 1) a higher odds of having a HRV ARI than a RSV ARI and 2) increased ARI severity. They used data from the Tennessee Children’s Respiratory Initiative (TCRI), a cohort that includes mother-infant dyads enrolled at the time of an infant ARI, September-May 2004-2008. Women were classified into mutually-exclusive groups (atopic asthma, nonatopic asthma, no asthma) based on self-reported asthma and evidence of allergen-sensitization. The authors determined viral etiology of the infant ARI by polymerase chain reaction and severity of infant ARI using a 13-point bronchiolitis severity score. The 343 infants with a sole HRV or RSV ARI were included. Using data obtained during study enrollment, the authors determined the association of maternal asthma and viral etiology and severity of infant ARI.
The authors found that infants with HRV ARIs were more likely to have a familial predisposition to asthma as measured by their mother having atopic asthma, then infants with RSV ARIs. In addition, among infants with HRV ARI, having a mother with atopic asthma was associated with more severe infection. On the other hand, among infants with RSV, having a mother with atopic asthma was not associated with more severe infection. The authors explain that for infants with HRV ARIs, a familial predisposition to asthma may partly explain the subsequent increased risk of asthma and help us to better understand the known association of HRV with asthma exacerbations.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.