The differential burden of acute rhinovirus infections in children with underlying conditions

Rhinoviruses (RVs) are a well-known trigger of wheezing episodes in children with asthma. Their role in other pediatric chronic medical conditions is not fully known.

Patients ≤21 years hospitalized or evaluated as outpatients with symptomatic RV infection were identified from 2011-2013. Patients were categorized based on the type of underlying disease and differences in clinical parameters, RV loads (CT values), viral, bacterial and fungal co-infections and clinical outcomes were compared between groups. Multivariable analyses were performed to identify the comorbidities associated with oxygen requirement, PICU admission, and prolonged hospitalization.

Of 1,899 children identified, 77.7% (n = 1477) had an underlying comorbidity including asthma/atopy (36.8%), prematurity (7.7%), chronic respiratory diseases (6.4%), congenital heart disease (CHD, 3.2%), immunocompromised hosts (ICH; 1.4%) and others (22.2%). Prevalence of comorbidities increased with age (70%, infants vs 84%-87%, children >1 year; p < 0.0001). Median RV loads were intermediate-high (24-26 CT values), irrespective of the underlying disease. RV/viral co-detections were identified in 11% of ICH vs 20%- 30% in all other children whereas bacterial co-infections were identified in 2.9% of children. Multivariable models identified asthma/atopy, prematurity, CHD and bacterial co-infections consistently associated with all three clinical outcomes (p < 0.0001). Older age and higher RV loads were also associated with increased odds of PICU admission.

The prevalence of comorbidities was high in children with RV infections. Of those, asthma/atopy, prematurity and CHD were consistently associated with severe disease. Higher RV loads and bacterial co-infections, although infrequent, were also associated with worse clinical outcomes, suggesting the importance of defining clinical phenotypes for future targeted interventions.