Respiratory viruses other than rhinovirus or respiratory syncytial virus, including human metapneumovirus, influenza virus, and human bocavirus, are important pathogens in acute wheezing illness and asthma exacerbations in young children. Whether infection with these viruses in early life is associated with recurrent wheezing and/or asthma is not fully investigated, although there are data to suggest children with human metapneumovirus lower respiratory tract infection may have a higher likelihood of subsequent and recurrent wheezing several years after initial infection.