Human rhinovirus C infections mirror those of human rhinovirus A in children with community-acquired pneumonia

Abstract

Background: Human rhinoviruses (HRVs) are among the most common causes of community-acquired pneumonia (CAP) in children. However, the differential roles of the three HRV species HRV-A, HRV-B, and HRV-C in pediatric CAP are not fully understood.

Objective: To determine the distribution of HRV species and their roles in children hospitalized with CAP in Beijing, China.

Study design: Nasopharyngeal aspirates were collected between April 2007 and March 2008 from 554 children with a primary diagnosis of CAP. HRVs in the clinical samples were detected by RT-PCR and by sequencing. Infections with other respiratory viruses were identified by PCR.

Results: HRVs were detected in 99 patients (17.87%). Among these patients, 51.52% tested positive for HRV-A, 38.38% for HRV-C, and 10.10% for HRV-B. HRVs were detected throughout the study period. The monthly distribution of HRV infections varied with HRV species. Median age, gender, symptoms, severity, and duration of hospitalization for single HRV-C infections were similar to those observed for single HRV-A infections. Co-infections with other respiratory viruses were detected in 57.58% of the HRV-positive children. HRV/RSV dual infections were correlated with a higher frequency of shortness of breath (HRV-A group, P(2 tail)= 0.01; HRV-C group, P(2 tail) = 0.015) and lower median ages (HRV-A group, P(2 tail) = 0.049; HRV-C group, P(2 tail) = 0.009).

Conclusion: Our study shows that HRV-C strains circulate at a prevalence intermediate between HRV-A and HRV-B. The severity of clinical manifestations for HRV-C is comparable to that for HRV-A in children with CAP. These findings point to an important role of both HRV-A and HRV-C in pediatric CAP.

Fig. 1

Seasonal distribution of the different HRV species in children with CAP. Detection numbers of HRV-A, HRV-B, and HRV-C positive samples are shown for the indicated month. The number of samples analyzed during each month is indicated under the corresponding column.

Fig. 2

Serotype distribution in single infections or mixed infections with HRV-A or HRV-B. All HRV serotypes of HRV-A and HRV-B detected in this study are shown, including 28 HRV-A serotypes and 8 HRV-B serotypes.