Aim: Viral markers have been studied extensively world over to inform environmental water quality assessment. Enteric viruses based monitoring platform has been prioritized compared to bacterial markers’ due to their ubiquity and varied human and animal health implications. In this study, the relationship between the occurrence of enteric viruses with reference to adenoviruses and enteroviruses and the physical water quality characteristics were assessed from water samples collected from Lake Victoria in Kenya. In order to understand the dynamics of season driven contamination, we also analyzed seasonal behavior of the lake’s catchment area in terms of rainfall effects.
Methodology: Physical quality parameters were measured on site while viral analysis was carried out by molecular method using nested Polymerase chain reaction.
Results: From the 216 samples that were analysed for viral contamination, enteric viral genomes were discovered in 18 (8.3 %) of the samples. Out of half of the samples (108) collected during the rainy season, enteric viral genomes were detected in 9.26 % (10), while 8 (7.41 %) samples tested positive from another 108 samples collected during the dry season. Most of the samples had an average of physical water quality parameters that were within the range accepted by the World Health Organization (WHO) with exemption of turbidity which was above the recommended 5 NTU from some sampling sites.
Conclusion: There was no significant correlation noted between the physical water quality characteristics and the enteric viruses’ occurrence. Neither wet season nor dry season was significantly associated with the prevalence of the viruses in Lake Victoria waters. Future work: Continuous and long term surveillance of the lake water to accurately monitor for the contaminants and possible correlation between chemical, physical, biological characteristics with hydrological changes is recommended. This would be important to inform proper management of the source waters.
Keywords: Physical quality, Biological quality, Enteric viruses, Adenoviruses, Enteroviruses, Surface waters, Seasonality