Molecular surveillance and genetic analyses of bufavirus in environmental water in Thailand.

Bufavirus (BuV), a recent discovery virus of the family Parvoviridae, has been suggested to be a potential causative agent of diarrhea in humans. The prevalence of BuV has been demonstrated mostly in fecal specimens of diarrheic patients. Little is known about the presence of BuV in the environmental water. The aim of the present study was to conduct a surveillance for BuV in the environmental water in Thailand. A total of 125 water samples were collected during November 2016 and July 2018 from six different areas in Chiang Mai city, Thailand. Water samples were concentrated and extracted to obtain BuV genomic DNA. The BuV was screened by amplification of NS1 region using nested-PCR. The detected BuV was further characterized by amplification of VP2 region. The NS1 and VP2 genes were sequenced and analyzed phylogenetically. The BuV strain (CMW88/18) detected in this study belonged to BuV1 with the prevalence of 0.8%. The CMW88/18 strain was most closely related to human BuV1 strains reported previously worldwide suggesting contamination of BuV in the environmental water could be a potential source of infection in human.