Sargeant compiled information on the available methods for identifying human versus nonhuman sources of fecal contamination in surface waters. The document describes each method, lists the advantages and disadvantages of each, and provides examples of application. Different ratios indicate the presence of human or nonhuman bacteria. Streptococcal Population Profiles. Species composition is used to indicate host animals.
Composition varies among types of animals and has been quantified for human, nonhuman, and dairy.
Some bacteria strains are specific to certain animal species and can be identified as originating within that animal group. For example, Rhodococcus coprophilus is primarily associated with domestic farm animal fecal pollution. Phages are viruses that infect bacteria-they can multiply in sewage and therefore can be used to indicate the presence of human fecal pollution. Multiple Antibiotic Resistance. Bacteria are analyzed for their resistance to various antibiotics.