Genetic Comparison of Human Parainfluenza Virus Type 3 Detected in Respiratory Samples from Patients with Encephalopathy and Airway Inflammation in Aichi Prefecture, Japan

• Published in: Japanese Journal of Infectious Diseases Vol. 77; no. 3; pp. 155 - 160
• Main Authors: Adachi, Hirokazu, Minagawa, Hiroko, Hirose, Emi, Nakamura, Noriko, Niimi, Hitomi, Saito, Noriko, Ito, Miyabi, Sato, Katsuhiko, Yasui, Yoshihiro
• Format: Journal Article
• Language: English
• Published: Japan National Institute of Infectious Diseases 31.05.2024; Japan Science and Technology Agency
• Subjects: Adolescent; Adult; Aged; Brain Diseases - virology; Child; Child, Preschool; Encephalitis; Encephalitis, Viral - virology; Encephalopathy; Female; human respirovirus 3; Humans; Infant; Japan - epidemiology; Male; Middle Aged; Parainfluenza; Parainfluenza Virus 3, Human - genetics; Parainfluenza Virus 3, Human - isolation & purification; Phylogeny; Respiratory diseases; Respiratory syncytial virus; Respiratory Syncytial Virus, Human - genetics; Respiratory Syncytial Virus, Human - isolation & purification; Respiratory tract; Respiratory tract diseases; Respiratory tract infection; Respiratory Tract Infections - epidemiology; Respiratory Tract Infections - virology; respiratory virus; Respirovirus Infections - epidemiology; Respirovirus Infections - virology; Viruses; Young Adult; Japan; human respirovirus 3; respiratory virus; encephalopathy
• ISSN: 1344-6304; 1884-2836; 1884-2836
• DOI: 10.7883/yoken.JJID.2023.265

Human parainfluenza virus type 3 (HPIV-3, human respirovirus 3) is the second most frequently detected virus in lower respiratory tract infections in children after human respiratory syncytial virus (HRSV). HPIV-3, similar to related respiratory viruses such as HRSV and influenza virus, may cause encephalopathy; however, the relevance of HPIV-3 as a pathogenic factor in encephalopathy is unknown. We attempted to detect HPIV-1, HPIV-2, HPIV-3, HPIV-4, HRSV, and human metapneumovirus (HMPV) in 136 patients with encephalitis/encephalopathy or suspected encephalitis/encephalopathy during a 6-year period from 2014 to 2019. HPIV-3 was detected in 6 patients, followed by HRSV in 3 patients. The HPIV-3 strains detected were closely related to those detected in a patient with respiratory disease during the same period. Although HPIV-3 is less widely recognized than HRSV as a triggering virus of encephalopathy, our results suggest that HPIV-3 is as important as HRSV. Surveillance of the causative viruses of encephalopathy, including HPIV-3, would help clarify the causes of encephalopathy in Japan, as the cause is currently reported in less than half of cases in Japan.