ASSESS LEVELS OF PATHOGENIC E. COLI IN THE ANACOSTIA RIVER
Environmental Microbial and Food Safety Laboratory
2011 Annual Report
1a.Objectives (from AD-416)
The objectives of this research are three-fold: (i) to detect and quantify pathogenic Escherichia coli (e.g. E coli 0157) in the Anacostia River,(ii) to develop a fecal source tracking approach with respect to the upstream fecal contamination problem in the Anacostia River, and (iii) to monitor water quality on fecal coliform in the downstream portion of the Anacostia River.
1b.Approach (from AD-416)
Samples of the Anacostia River water will be obtained by the Anacostia Watershed Society (AWS) staff. These samples will be analyzed for pathogenic E. coli using immunological and genetic methods previously developed by USDA scientists. Staff from the AWS will perform testing in regards to fecal coliform and other parameters for their survey. ARS will provide the use of its laboratory equipment to AWS. AWS will supply reagents for parameters of their own testing. Participation in the partnership by the AWS is contingent upon the ability to obtain funding for this program from outside sources in order to satisfy the financial obligations incurred by AWS for this program.
Water-borne pathogenic E. coli, particularly enterohemorrhagic E. coli (EHEC), pose a serious threat to public health. There is relatively little information on documenting the actual levels of pathogenic E. coli in various watersheds. Specifically, there is no data on levels of pathogenic E. coli in the Potomac River watershed. It is well established that humans, wildlife and agricultural animals are all sources of pathogenic E. coli. The Potomac River watershed receives inputs from all of these sources; however, the relative contributions from each are unknown. The goal of this collaboration is to establish the levels of pathogenic E. coli in the Anacostia River, an urban/suburban watershed, which flows into the Potomac River and finally the Chesapeake Bay. Research to date indicates that the upper sections of the Anacostia River have higher levels of microbial contamination than the lower section, presumably due to dilution from the Potomac River. Enteropathogenic E. coli (EPEC) strains have been isolated from the Anacostia River; these are similar to (EHEC), but less pathogenic.
From May through September, water samples from the Anacostia River and tributaries are analyzed weekly at EMFSL by a technician employed by the AWS. During the remaining months, there is monthly communication to review water quality data.