Concentrations of Pathogens and Indicators in Animal Feces in the Sydney Watershed

Abstract

A fecal analysis survey was undertaken to quantify animal inputs of pathogenic and indicator microorganisms in the temperate watersheds of Sydney, Australia. The feces from a range of domestic animals and wildlife were analyzed for the indicator bacteria fecal coliforms and Clostridium perfringens spores, the pathogenic protozoa Cryptosporidium and Giardia, and the enteric viruses adenovirus, enterovirus, and reovirus. Pathogen and fecal indicator concentrations were generally higher in domestic animal feces than in wildlife feces. Future studies to quantify potential pathogen risks in drinking-water watersheds should thus focus on quantifying pathogen loads from domestic animals and livestock rather than wildlife.The current trend in minimizing pathogen health risks to water supplies is to use a risk management-based approach to ensure delivery of high-quality water. This approach utilizes multiple barriers within the water system, including effective control of contaminant inputs through watershed management. One potential source of these pathogens in drinkingwater watersheds is the feces of domestic and wildlife animal populations. Pathogens from animal feces may enter waterways by direct deposition or as a result of overland runoff containing fecal material deposited in the watershed. To construct a source material budget of pathogen inputs, it is necessary to estimate the potential impact of animal populations on surface water quality (15). Subsequent analysis can then be performed to estimate the proportion of the source material that will be inactivated through natural decay and environmental stressors, how much may be transported to the stream network, and the proportion that represents a risk of human infection.The initial requirement for the development of a source material budget is to estimate the concentration of potential pathogens in animal feces (shedding intensity). There is limited published information on the concentration and input load of potential waterborne pathogens and fecal indicator bacteria in wildlife (native and feral animal) populations (2,3,8,19). Yet it is these animals that often have the greatest access to the riparian zones and reservoir surrounds in watersheds, since, by definition, their movements are largely uncontrolled, making surface water protection difficult. By comparison, data for potential pathogen concentrations in the feces of domestic animals are more abundant, particularly for the enumeration and prevalence of the protozoan parasites Cryptosporidium and Giardia spp. (4-7, 18, 24, 25).This study was undertaken to provide a cross-sectional estimate of the intensity of shedding of pathogenic and indicator microorganisms in animal feces present in a large, semiprotected drinking-water watershed. The study quantified potentially pathogenic protozoa (Cryptosporidium and Giardia), enteric viruses (adenovirus, enterovirus, and reovirus), and indicator organisms (fecal coliforms and Clostridium perfringens spores) in fecal samples from watershed animals. The latter are t...

Development of a quantitative PCR (qPCR) for Giardia and analysis of the prevalence, cyst shedding and genotypes of Giardia present in sheep across four states in Australia

“…There are only limited reports on the concentration and environmental loading of Giardia cysts as a result of faecal contamination by sheep. One study reported that the range of cyst shedding for adult sheep in Sydney catchments was 0 -504 cysts g -1 with a median of 26 cysts g -1 (Cox et al, 2005). However this was based on immunomagnetic separation (IMS) with recovery rates varying from 13-73%.…”

“…Cyst transport to surface water can occur by deposition of manure directly in the water or by wash-off in surface runoff. Current risk management practices for minimizing pathogen health risks to water supplies require both prevalence and the concentration of pathogens in faeces to establish pathogen source loads in watersheds, enabling the assessment of risk from faecal contamination of source waters (Cox et al, 2005). Accurate quantification of Giardia cysts in animal faecal deposits on land is an essential starting point for estimating catchment Giardia loads.…”

Distribution of Enterotoxin Gene-positive <i>Clostridium perfringens</i> Spores among Human and Livestock Samples and its Potential as a Human Fecal Source Tracking Indicator

“…A more recent survey of domestic animals and wildlife showed that the concentration of C. perfringens spores was 2.9 × 10 5 in pigs, 4.6 × 10 3 in poultry, and 3.6 × 10 5 and 3.3 × 10 6 per gram in dogs and cats. High concentrations were detected in domestic animals but rarely in wildlife [34].…”

Influence de la densité animale sur la concentration des coliformes fécaux dans les cours d’eau du Québec méridional, Canada

“…Les résultats des tests d'hypothèse sont également confirmés par les analyses (GRAVES et al, 2007;MEALS, 1992;PAtNI et al, 1985). Les CF mesurés à ces stations peuvent provenir des déjections des animaux d'élevage, des humains et de la faune dont le contenu typique en CF varie de 10 6 à 10 10 uFC•100 mL -1 (ASAE, 1998;COx et al, 2005;MDDEP, 2009b). Des sources de CF d'origine non fécale existent également, comme Klebsiella dans les rejets de papetières, absents des sous-bassins versants de la présente étude, ainsi que Enterobacter et Citrobacter (SBSC, 1992) et des souches de E. coli adaptées à l'environnement (kON et al, 2009).…”