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<OL> <LI> Detection of a new infectious agents: This objective would use available diagnostic methods to detect emerging infectious diseases in livestock and poultry. This would require diagnostic evaluation of clinical specimens and dead animals submitted to the Diagnostic Center for Population and Animal Health. <LI> Characterization of new infectious agents: This objective involves the laboratory characterization of infectious agents that cause emerging diseases. This would include biochemical characterization and genetic characterization of those agents. <LI> Characterization of the host response to the infectious agent and disease transmission: The purpose of this objective is to characterize the disease process in affected species of livestock and poultry. This would include description of gross and microscopic lesions, determining the temporal onset of clinical signs of disease and progression of lesions, and determining the epidemiological aspects of the disease that relate to disease transmission.
NON-TECHNICAL SUMMARY: Critical information is needed to detect, diagnose, and predict transmission of newly emerged infectious disease. This project will obtain information on pathogenesis and transmission of newly emerged infectious diseases of livestock and poultry. This project is designed to detect and characterize emerging pathogens of livestock and poutlry for the purpose of alerting producers and veterinarians of new diseases that would affect the well being of livestock and poultry.
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APPROACH: The approach for Objective 1 involves use of standard diagnostic laboratory methods for detection of infectious agents. Those methods include bacterial isolation on agar and broth culture medium, virus isolation in cell culture and embryonated eggs, polymerase chain reaction amplification of the 16s ribosomal RNA gene of bacteria or the 18s ribosomal RNA gene of protozoa (followed by nucleic acid sequencing), or polymerase chain reaction amplification of select genetic targets that are shared by genera of viruses (again, followed by nucleic acid sequencing). A close working relationship will be established with veterinary academic clinicians, veterinary practitioners, veterinary diagnostic pathologists, and diagnostic microbiologists. This will be critical because emerging diseases usually are recognized first by clinical and diagnostic specialists that are familiar with, and can differentiate, the known diseases in a geographic region. The approach for Objective 2 involves use of laboratory methods that allow characterization of an infectious agent. Those methods include a variety of serologic assays, Western blotting,, immunoprecipitation, PCR, nucleic acid sequencing, and searches of bioinformatics data bases. Growth characteristics of the agents in vitro would be done to provide data useful for the diagnostic detection of the agent and would include use of standard bacterial culture conditions and selective media, standard procedures to determine the temporal sequence of viral RNA transcription and translation in vitro, and procedures that allow temporal observation of the characteristics of viral cytopathic effect in cell culture. Some of the experimental procedures needed to characterize a newly discovered infectious agent would require establishing collaborative relationships with microbiologists, molecular biologists, parasitologists, and virologists for advice and assistance. The approache for Objective 3 involves the creation of detailed written field observations of the disease process in poultry or livestock and use of specialized histologic procedures, such as tissue fixatives other than 10% neutral buffered formalin solution or specialized stains, for observation and detailed description of microscopic lesions. Animal experiments are not anticipated at this time.