Studies examining respiratory viruses in nasalwash specimens from children with respiratory tract infections showed that hMPV was detected in approximately 5 to 12% of children tested (25) (26) (27) . hMPV infection was not associated with asthma exacerbations in children greater than 5 years of age (25) , but was found to be associated with wheezing in children younger than 5 years of age (26, 27, 29) .