| human parainfluenza virus 4 outbreak and the role of diagnostic tests. | owing to the difficulties in isolating the virus and the lack of routine surveillance, the clinical significance of human parainfluenza virus 4 (hpiv-4) is less well defined than that of the other human parainfluenza viruses. we describe the first outbreak of hpiv-4 infection in a developmental disabilities unit, involving 38 institutionalized children and three staff members, during a 3-week period in autumn 2004. most subjects had upper respiratory tract infections (urti), while lower respirat ... | 2005 | 16145100 |