EXTENT OF PATHOGENIC BACTERIA AND ANTIBIOTIC RESISTANCE GENES IN STORM DRAIN OUTFALLS

Stormwater contamination can degrade environmental health and pathogens found in stormwater can pose a significant health risk to humans. The extent to which microbiological contaminants in water can affect human health has not been well documented. In this study, the abundance of 11 bacterial pathogens and 47 antibiotic resistance genes (ARGs) were determined using high-throughput microfluidic qPCR (MFQPCR) in several storm drain outfalls (SDOs) during dry and wet weather periods in Tampa and Hillsborough Bay, Florida, USA. Data generated in this study were also compared with the abundance of fecal indicator bacteria (FIB) and sewage-associated molecular markers (i.e., Bacteroides HF183 and crAssphage markers) collected in a recent study (Ahmed et al., 2018). The results indicated that SDOs were the hotspots for microbial pollution in Tampa and Hillsborough Bay as the concentration of FIB, sewage-associated markers, bacterial pathogens and many ARGs in water samples were high. The mean concentrations of the majority of microbiological contaminants were higher in samples collected during wet weather than dry weather periods. Presence of sewage-associated markers along with ARGs associated with sewage suggesting aging sewage infrastructure contributing to the pollution load in the Bay. The human health risks associated with exposure to these contaminants remains unknown and should be estimated using risk assessment tools. Further research should focus on collecting spatial and temporal data on the microbiological contaminants especially viruses in SDOs.