Open AccessHuman metapneumovirus (hMPV) is a recently discovered virus that causes respiratory illness in children and can lead to hospitalization. This study was undertaken to further understand hMPV-associated illness, compare clinical characteristics of hMPV and RSV and establish the utility of routine screening for hMPV.hMPV-associated illnesses were retrospectively identified and described among children with respiratory symptoms admitted to a tertiary care center in southeast Michigan during the 2006-2007 respiratory viral season. A convenience sample of 256 nasopharyngeal specimens was subjected to nucleic acid extraction and amplification to identify those specimens positive for hMPV. Medical record review was undertaken to retrieve demographic and clinical data of patients with hMPV, comparing them to RSV-positive patients and patients evaluated for respiratory symptoms who were negative for hMPV and RSV.hMPV was the second most commonly identified virus after RSV. hMPV-positive patients were older than RSV-positive patients. Among hMPV-positive patients, pneumonia was diagnosed in 37.5%, bronchiolitis was diagnosed in 31.2%, peribronchial cuffing was present on chest radiographs of 37.5%, antibiotic treatment was used in 81.2% and admission to the ICU was seen in 37.5%. Finally, hMPV-positive patients were more likely to have fever than RSV-positive patients or patients negative for hMPV and RSV. hMPV is a major pathogen associated with hospitalization of children and is associated with the same severity of illness as RSV but in a slightly older population. Due to apparent prevalence and severity of illness, routine screening should be implemented.