Epidemiology and genotypic diversity of rhinovirus in school-age children with acute respiratory illnesses seeking medical care.

Background: Rhinovirus (RV) associated acute respiratory illness (ARI) data come mostly from infants and young children. We present data from 5 to 17-year-olds to characterize RV species A, B and C.

Methods: During December 1, 2016-Nov 30, 2017, seven U.S. New Vaccine Surveillance Network (NVSN) sites performed active pediatric ARI surveillance of inpatients (IP) and emergency department (ED) patients using molecular platforms to detect multiple respiratory pathogens. RV or RV/enterovirus (EV) positive specimens without co-detections were sequenced. Demographic and clinical data collected via parent interview and chart review were analyzed descriptively by RV species, month, and hospital setting, using chi-squared tests for comparisons.

Results: RV or RV/EV was detected in 581/2298 (25.3 %) ARI patients; 529 were single detections, 516 of these had sufficient sample for sequencing, and 420 (81.4 %) yielded sequence results: RV-A (183, 35.5 %), RV-B (16, 3.1 %), RV-C (210, 40.7 %), non-typeable RV (2, 0.4 %), and EV (9, 1.7 %). Among 52 RV-A, 8 RV-B and 44 RV-C unique types identified, A49 (32, 61.5 %), B6 (5, 62.5 %) and C15 (22, 50 %) were predominant. History of asthma was reported in 65.4 % RV-A, 50 % RV-B and 78.5 % RV-C patients (p = 0.005). Hospitalization occurred in 63.4 % RV-A, 37.5 % RV-B and 71.4 % RV-C patients (p = 0.012). RV-C detections peaked during winter and RV-A peaked during summer-fall.

Conclusions: RV exhibited genetic diversity in 5-17-year-old ARI patients, and circulation differed by RV species. Among children seeking care in ED or hospital settings, with confirmed RV or RV/EV single detections, hospitalization was more common with RV-A and -C than RV-B.