Comparison of respiratory disease by human metapneumovirus and respiratory syncytial virus in children

ABSTRACT

PURPOSE: Human metapneumovirus (hMPV) is known to result in clinical manifestation similar to respiratory syncytial virus (RSV) in children. But some recent studies showed different features. This study compared the clinical manifestation of respiratory disease between hMPV and RSV. METHODS: A total of 801 children who admitted to Seoul St. Mary's Hospital for respiratory infection from January to June, 2012 were enrolled. Respiratory viral polymerase chain reaction (PCR) using nasopharyngeal swab was performed in all children. We grouped hMPV positive children and RSV positive children and compared clinical features between them by retrospective chart review. RESULTS: Among 801 children, 365 showed one virus PCR positive with 44 showing hMPV and 41 showing RSV. Respiratory diseases were upper respiratory infection, acute bronchitis, acute bronchiolitis and pneumonia. The peak season was March and April for hMPV and February and March for RSV. Fever incidence, fever duration and neutrophil percent of complete blood cell count were higher in hMPV group than RSV group (P<0.05). The mean age of hMPV group was higher than RSV group (P<0.05). But in acute bronchiolitis children, there was no mean age difference between two group. Acute bronchiolitis incidence declined with increased age for both group (P<0.05). The hMPV group showed relatively lower bronchiolitis and higher pneumonia incidence than RSV group, suggesting relation with age. CONCLUSION: Respiratory infection by hMPV developed at late winter and spring, slightly later than RSV and at older age. The lower incidence of acute bronchiolitis for hMPV infection than RSV is maybe due to older age than RSV.