Environmental Transmission of Noroviruses and Study of Fecal Microorgnisms as Viral Indicators in the Suyeong River in Busan, Korea

ABSTRACT

In order to investigate the occurrence of norovirus in rivers and beaches, a total of 81 samples were tested at seven sites of Oncheon stream, Suyeong river and Gwanganri beach in Busan from January to November, 2017. To improve the detection of norovirus from sea water, we applied the inorganic cation-coated filter method which showed 48.8% ± 12.2% (n=3) and 27.4% ± 6.0% (n=3) recovery yields from river water and sea water inoculated with Norovirus, respectively. Norovirus was detected in a total of four samples (4.9%), which all were GII genotype. Norovirus GII was detected in three samples at two waste water treatment plants (WWTP) outlet and one sample at about 500 meter downstream from WWTP in both the winter and spring seasons. We also monitored fecal indicator organisms, Escherichia coli (E. coli), Enterococcus and coliphages [somatic coliphages (SC), male-specific coliphages (MSC)] to analyze the potential transmission of enteritis causative agent in dry and wet days. Bacterial influences were found at the site of the WWTP effluents in the dry days and spread further to the costal beach in the wet days. But no viral influences were found in the river downstream in both dry and wet days.