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-  Environmental Microbial and Food Safety Laboratory 
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**Location: Environmental Microbial and Food Safety Laboratory**
**2006 Annual Report**
**1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)?  How serious is the problem?  Why does it matter?**													This project is aligned with National Program 108.  This project replaces 1265-32000-073-00D. 
The protozoan parasites Cryptosporidium and Giardia are clearly recognized as food- and water-borne pathogens worldwide. Microsporidia have been designated by the CDC as an emerging pathogen of concern. However, little is known of their prevalence, distribution, or epidemiology. These three groups of agents have been responsible for numerous outbreaks of severe diarrheal disease in thousands to hundreds of thousands of persons in the United States. The economic impact of giardiasis and cryptosporidiosis, stemming from lost productivity, is enormous, while the impact from microsporidial illnesses remains largely unknown. Cryptosporidium parasites have now been reported from 154 species of mammals, mostly by microscopic identification. It is now recognized that this method is unable to distinguish one species of Cryptosporidium from another. Cryptosporidium parvum, a zoonotic species, is the most prevalent species in preweaned dairy and beef calves, causing morbidity and mortality with associated economic losses. A single infected calf can excrete tens of billions of infectious oocysts into the environment. Healthy persons can acquire infection from the ingestion of less than 100 such oocysts in contaminated water or food items, resulting in several days of diarrhea and other flu-like symptoms. Infants, the elderly, and immune-compromised persons are at high risk because pharmaceuticals are not available to prevent infection and only one drug has been approved by the FDA- for treatment of children. Despite numerous reports of Cryptosporidium in cattle, their role in environmental contamination with species infectious for humans is not clear. The ARS is investigating the prevalence and species of Cryptosporidium in livestock of different ages and attempting to determine the relationship of the animal isolates to the organisms that cause disease in humans and in the animals themselves.  Giardia is the most commonly diagnosed intestinal parasite in public health laboratories in the United States and has been the most frequently identified agent associated with drinking water outbreaks in the U.S. for many years. There has been increasing evidence of Giardia infection in livestock, raising the question of how agriculture may contribute to environmental contamination. The ARS is investigating the prevalence of Giardia in livestock species of different ages and attempting to determine the relationship of isolates from livestock to the organisms that cause disease in humans. Thirteen species of Microsporidia have been identified in fulminating infections in AIDS patients. Little is known about the actual sources of human infection with Microsporidia but reports from Europe indicate that cattle and pigs are potential sources. ARS scientists are conducting surveys of cattle to detect Microsporidia, to determine the prevalence in cattle of different ages, and to compare the species found in cattle with those infecting humans. Cryptosporidium, Giardia and Microsporidia have been identified as waterborne pathogens of concern by the U.S. Environmental Protection Agency and the World Health Organization. Because clean drinking water starts with clean source water, protection of both surface and ground water against contamination with manure from animal feeding operations and discharge from waste water treatment plants have become issues of national importance. These issues are affecting decisions by such agencies as the US/EPA and state environmental agencies by restricting animal farming practices in proximity to water. In addition, the impact of cryptosporidiosis on the animals themselves can be devastating, resulting in morbidity, poor growth, and even mortality, with associated economic losses. The impact of the work will be to provide accurate information on the prevalence and species (or genotypes) of these three groups of organisms so that action agencies can make decisions based on appropriate and reliable scientific data.						
**2.List by year the currently approved milestones (indicators of research progress)**													OBJECTIVE 1: Detection                  (2006-2007)   Exp Design 1a -       Develop multiplex PCR test         2006-2007   Exp Design 1b       Monoclonal antibody detection     2006-2007OBJECTIVE 2: Epidemiology              (2006-2010)   Exp Design 2a -                      2006-2010                1. Dairy cattle: Blastocystis      2. Sheep: all zoonotics      3. Pigs: all zoonotics      4. Feedlot cattle: all zoonotics    Exp Design 2b -      Environ contam from agric runoff   2006-2010   Exp Design 2c -      Cross species infectivity          2006-2010OBJECTIVE 3: Treatment/control         (2006-2010)   Exp Design 3a -      Colostrum production/testing       2006-2007   Exp Design 3b Subobjective 3b1 -      Cryptosporidium excystation        2008-2010      Exp Design 3b Subobjective 3b2 -      Giardia encystation                2006-2008  Exp Design 3c -     Nucleoside drug testing             2009-2010						
**4a.List the single most significant research accomplishment during FY 2006.**													ARS scientists conducted cross species infectivity studies with Giardia isolated from cattle. The most prevalent Giardia found in cattle in a multistate study (genotype E) was not infectious for other animal species tested. The less often found genotype (genotype A),which has been reported to infect humans and other animals, was isolated from cattle and found to infect gerbils and sheep.  This finding demonstrated that cattle can be a source of a Giardia genotype reported in human infections but the predominant genotype of Giardia found in cattle does not appear to be zoonotic. This finding could influence state and federal regulations regarding farm management, manure management, and proximity of livestock to surface water. National Program Component 108.  						
**4b.List other significant research accomplishment(s), if any.**													1. A new genotype of Cryptosporidium was identified in sheep, distinguishing them from the pathogenic C. parvum providing epidemiologists with a new parasite  to differentiate from pathogenic species found in drinking water or food specimens. 
2. Identified potentially zoonotic Giardia in sheep.
3. Developed monoclonal antibodies against a virus found within Cryptosporidium parvum.						
**4c.List significant activities that support special target populations.**													None.						
**4d.Progress report.**													None.						
**5.Describe the major accomplishments to date and their predicted or actual impact.**													Data are still being collected early in this first year of the project. Molecular, biological, and immunological techniques that were developed in the previous project will aid in the rapid detection of the Cryptosporidium parasite in surface water, ground water, and drinking water. A recombinant protein that was produced by genetic engineering that is similar to a constituent on the surface of Cryptosporidium and monoclonal antibodies were developed that detect the parasite. ARS scientists developed a multiplex molecular test for detection of Cryptosporidium oocysts in water samples and are now analyzing the data. This assay speeds up the analysis time for identifying water samples that contain Cryptosporidium parasites because, once a specimen has been prepared, multiple species can be analyzed in a single test in a short time. ARS scientists also refined methods for recovery and molecular testing of Cryptosporidium oocysts recovered from the environmental waters and sediments. This research is essential in identifying sources of the parasite in the environment and could ultimately be used to manage run-off from agricultural and urban areas. The most in-depth study of Giardia in any animal species has been completed in cattle over the past four years and has demonstrated the persistance of relatively high levels of infection with a livestock specific strain and the sporadic presence of a strain infectious for humans. In the new project this type of study is being applied to other livestock species- sheep and swine. Enterocytozoon bienuesi a human pathogen was identified in cattle and wildlife for the first time in North America, and the most extensive and widespread documentation of its presence in animals was conducted in the past project. In the new project this type of study is being applied to other livestock species- sheep and swine.						
**6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)?  What are the constraints, if known, to the adoption and durability of the technology products?**													Three gene sequences were patented and licensed by ARS to biotechnology/ pharmaceutical industries from the immediate past project. Potential new products have not yet been developed in the new project.
As participants in a collaborative project with scientists from the National Oceanic and Atmospheric Administration (NOAA) and the Centers for Disease Control (CDC) ARS scientists are developing technologies for detecting contamination of environmental waters with fecal-borne pathogens potentially from humans and livestock species. 
Submitted seventeen (17) new gene sequences to GenBank for Cryptosporidium, Giardia and Microsporidia from coyotes, beavers and cats.						
**7.List your most important publications in the popular press and presentations to organizations and articles written about your work.  (NOTE:  List your peer reviewed publications below).**													None.						
**Review Publications***Fayer, R., Santin, M., Xiao, L. 2005. Cryptosporidium bovis n. sp. (apicomplexa: cryptosporididae) from cattle, bos taurus. Journal of Parasitology. 91(3):624-629.**Santin, M., Dixon, B., Fayer, R. 2005. Genetic characterization of cryptosporidium isolates from ringed seals (Phoca hispida) in northern Quebec, Canada. Journal of Parasitology. 91(3):712-716.**Collins, M.V., Flick, G.J., Smith, S.A., Fayer, R., Croonenberghs, R., O'Keefe, S., Lindsay, D.S. 2005. The effect of high pressure processing on Eastern oysters (Crassostrea virginica) experimentally infected with cryptosporidium parvum. Journal of Eukaryotic Microbiology. 52(6):500-504.**Santin, M., Trout, J.M., Fayer, R. 2005. Enterocytozoon bieneusi genotypes in dairy cattle in Eastern United States. Parasitology Research. 97:535-538**Collins, M.V., Flick, G.J., Smith, S.A., Fayer, R., Rudendall, E., Lindsay, D.S. 2005. The effects of e-beam irradiation and microwave energy on eastern oysters (Crossostrea virginica) experimentally infected with Cryptosporidium parvum. Journal of Eukaryotic Microbiology. 52(6):484-488.**Fayer, R., Santin, M., Trout, J.M., Greiner, E. 2005. Prevalence of species and genotypes of Cryptosporidium found in one to two-year old dairy cattle in Eastern United States. Veterinary Parasitology. 135:105-112**Jenkins, M., Murphy, C.A., Trout, J.M., Fayer, R. 2006. An improved electron microscopic technique for the immunolabeling of Cryptosporidium parvum oocysts. Journal of Parasitology. 92:403-405.*    Project TeamFayer, Ronald Jenkins, Mark Miska, Kate  
Project Annual Reports FY 2009 FY 2008 FY 2007 FY 2006 Publications  Publications 
Related National Programs Food Safety, (animal and plant products)(108)  							Last Modified: 03/24/2010 		ARS Home |USDA.gov |Site Map |Policies and Links FOIA |Accessibility Statement |Privacy Policy |Nondiscrimination Statement |Information Quality |USA.gov |White House

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