Open AccessHuman Parainfluenza Virus 4 Outbreak and the Role of Diagnostic Tests
Author(s) -
Susanna K. P. Lau,
WingKin To,
P. Tse,
Alex K. H. Chan,
Patrick C. Y. Woo,
Hoi-Wah Tsoi,
Annie F. Y. Leung,
Kenneth S. M. Li,
Paul K.S. Chan,
Wilina Lim,
R Yung,
KwokHung Chan,
KwokYung Yuen
Publication year - 2005
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.43.9.4515-4521.2005
Subject(s) - human parainfluenza virus , virology , outbreak , respiratory tract infections , respiratory tract , medicine , virus , bronchiolitis , biology , antibody , respiratory system , immunology
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 respiratory tract infections (LRTI) occurred in three children (7%), one complicated by respiratory failure requiring ventilation support. All patients recovered. Nasopharyngeal aspirates tested for HPIV-4 were positive by reverse transcriptase PCR (RT-PCR) in all 41 cases (100%), by direct immunofluorescence in 29 of 39 tested cases (74%), and by cell cultures in 6 of 37 cases (16%), and serum was positive for antibodies against HPIV-4 in all 35 cases (100%) with serum samples available. In addition, RT-PCR detected HPIV-4 in four children (three LRTI and one URTI) out of 115 patients with community-acquired respiratory tract infection. Molecular analysis of the 1,198-bp phosphoprotein sequences showed that HPIV-4 isolates among the cases were genetically similar, whereas the community controls were more genetically distant, supporting nosocomial transmission of a single HPIV-4 genotype during the outbreak. Moreover, the HPIV-4 causing the outbreak is more closely related to HPIV-4A than HPIV-4B. HPIV-4 may be an important cause of more severe respiratory illness in children. The present RT-PCR assay is a sensitive, specific, and rapid method for the diagnosing HPIV-4 infection. To better define the epidemiology and clinical spectrum of disease of HPIV-4 infections, HPIV-4 should be included in the routine panels of respiratory virus detection on respiratory specimens.