UC Riverside

Regulations set forth by the United States Environmental Protection Agency (EPA) have significantly elevated standards for water treatment by ultraviolet light irradiation (UV). These standards are justified by resistances exhibited by double stranded DNA (dsDNA) viruses from the Adenoviridae family to UV treatment at 253.7 nm (UV254), but have not been validated by other waterborne microorganisms. Similarly structured microorganisms, like BK Polyomavirus (BKPyV), would allow for such assessments, but remain precluded by a lack of traditional infectious assays. Additionally, the rates of seroprevalence in human populations, as well as the modes of excretion, have generated interest in the utilization of polyomaviruses as alternative indicators of water quality.

Integrated assays, such as intracellularly delivered molecular beacons (MB), selectively target infectious virions, thereby surmounting limitations in current detection methodologies. This research describes the development of integrated assays for BKPyV to characterize its disinfection profile following exposure to UV254, chlorine, heat, and sunlight. The developed assays were also applied to Adenovirus 2 (Ad2) and Poliovirus 1 (PV1) following similar treatments. As expected, the genomic parallels between BKPyV and Ad2 resulted in similar resistance to UV254 inactivation, requiring 61.35 and 51.45 mJ/cm2 to reduce viral titers by an order of magnitude, respectively. The obtained results support current regulations for UV treatment and assess the utility of BKPyV as an indicator organism of water quality.