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Manure-borne Pathogens: Impact of Animal Agriculture on Microbial Water Quality. Jeanette A. Thurston-Enriquez USDA-ARS. Livestock Manure. Increase in CAFOs 500 million tons/year in U.S. 26 million tons/yr in NE. Public Health and Animal Waste. Animal waste agents Infectious
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Manure-borne Pathogens:Impact of Animal Agriculture on Microbial Water Quality Jeanette A. Thurston-Enriquez USDA-ARS
Livestock Manure • Increase in CAFOs • 500 million tons/year in U.S. • 26 million tons/yr in NE
Public Health and Animal Waste • Animal waste agents • Infectious • bacteria, viruses, protozoa • Chemical • nutrients, endocrine disrupters, antimicrobials
Manure-borne Pathogens of Concern Protozoan Parasites Pathogenic Bacteria Fungi Antibiotic Resistant Bacteria Viruses
In order to determine the human health impact of manure-borne pathogens we need to evaluate: • Occurrence • Survival/Persistence • Dissemination/Transport Manure, Manure Management Systems, & Surrounding Environment: Water, Air, Soil
Other Health-Related Microorganisms • Fecal Indicator Microorganisms • What? • Traditionally, bacteria of fecal origin • Total and fecal coliforms • Escherichia coli • Why? • Indicators of fecal contamination • Recreational and drinking water quality regulations • Faster, cheaper, easier detection
Waterborne Disease in the U.S. • 12-20 outbreaks/yr • 10-100 x higher • ~900,000 cases of waterborne microbial infections • Up to 900 deaths • >70% in >55 yrs
Water Sources Affecting Public Health Drinking Recreational Irrigation Foodborne
Contamination Routes RUNOFF Urban and storm water WWTP overflow Septic tank leakage Wildlife Agriculture Well head impacts Infiltration percolation Recreation Discharge Groundwater
Manure Dissemination • Land application • Aerosol generation • Leakage or overflow from storage lagoons or treatment ponds • Runoff from feed yards, manure-applied land, pasture land, etc.
Outbreak Source: Animal Ag. • Walkerton, 2001 • Land-applied cattle manure • Agricultural runoff to groundwater supply • Escherichia coli O157:H7 & Campylobacter • >2000 cases • 7 fatalities
Contributing Factors for Environmental Persistence and Transmission ofEnteric Pathogens • High numbers shed in feces • Increased survival • Low infectious dose • Increased resistance to disinfection/treatment • Multiple routes of transmission • Animal and human infections
Potential Routes of Human Exposure to Pathogens • Waterborne • Drinking and recreational water • Foodborne(can be related to waterborne) • Direct contact, irrigation water, ingestion of contaminated produce • Direct Contact • Aerosol Transmission • Transport to water supplies or food crops • Inhalation of aerosols • Contact
Possible Pathogen Transmission by Aerosols • Direct transmission or deposition onto food crops, fomites, or water Biosolids Land Application Livestock Spray Irrigation
Barriers Against Waterborne Disease • Drinking water and wastewater treatment • Disinfection & Filtration • Surface water monitoring/Source water protection • Point-of-use devices—disinfect/filter • Protection of recreational waters • Contaminant monitoring • Designation of specific uses
Limiting Microbial Transport:Manure Storage & Treatment Holding Ponds & Lagoons Compost
Limiting Microbial Transport:Aerosols • Top spray vs. drop spray • Keep tractor speed low; scrape moist soil • Low wind speed • Wind direction Land application Pen scraping
Microbial Reduction Prior to Land Application:Constructed Wetlands • Alternative waste management and treatment technology • Bacterial reduction: >80 % (prior to plant establishment) • Protozoan parasite reduction: >60 % (prior to plant establishment)
Environmental Loading Environmental Fate Treatment Effectiveness Alternative Treatments/Tech. Detection Methods Viability Sensitivity Specificity Emerging Pathogens **Risk Assessments Requires above information Manure-borne Pathogen Information Gaps