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Scott M.C.,University of Tennessee at Knoxville | Bannantine J.P.,Bacterial Diseases of Livestock Research Unit | Kaneko Y.,University of Tennessee at Knoxville | Branscum A.J.,University of Kentucky | And 4 more authors.
Foodborne Pathogens and Disease | Year: 2010

The use of enzyme-linked immunosorbent assays (ELISAs) is recommended for Johne's disease (JD) control in dairy herds. In 2006, we developed a novel ELISA test for JD, named EVELISA (ELISA using ethanol extract of Mycobacterium avium subsp. paratuberculosis), which showed higher sensitivity than commercial ELISA tests. To further investigate the performance of EVELISA, we obtained 38 serum samples from cattle in a JD-free herd with suspected cases of serological false-positive reactions. When these samples were tested using the EVELISA and a commercial ELISA test, more than 70% of the samples were falsely identified as JD positive. Antibodies in the serum samples reacted strongly with antigens of various environmental mycobacteria, suggesting the presence of cross-reactive antibodies in the samples. The possible cross reactions in the EVELISA were inhibited markedly by the use of Mycobacterium phlei antigens for antibody absorption. When these samples were tested, 8 samples were classified as positive for JD by the EVELISA with the antibody absorption, whereas 27 samples were classified as positive for JD by the commercial ELISA. For an estimation of tentative sensitivity and specificity, the ELISA tests were performed on 38 serum samples from JD-negative herds with no suspected cases of serological false-positive reaction and 68 samples from cattle diagnosed as positive for M. avium subsp. paratuberculosis infection by fecal culture test. Sensitivity and specificity of the EVELISA with preabsorption of serum with M. phlei ("ethanol vortex absorbed-ELISA" or EVA-ELISA) were estimated to be 97.1% and 100%, respectively, whereas those of the commercial ELISA were 48.5% and 97.4%, respectively. Further, in 85 fecal culture-negative cattle in JD-positive herds, higher sensitivity of the EVA-ELISA than the commercial ELISA was demonstrated by a Bayesian analysis. This study indicates that the EVA-ELISA may form a basis for a sensitive diagnostic test with a higher level of specificity than that of the current commercial ELISA test. Copyright 2010, Mary Ann Liebert, Inc.

Olsen S.C.,Bacterial Diseases of Livestock Research Unit | Carlson S.A.,Iowa State University
International Journal of Antimicrobial Agents | Year: 2015

Plazomicin is a next-generation aminoglycoside with a potentially unique set of clinical characteristics compared with other aminoglycosides. This study assessed the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of plazomicin against 15 clinical isolates as well as three reference strains representing Brucella abortus, Brucella melitensis and Brucella suis. These data were compared with those obtained for six other aminoglycosides and two aminocyclitols. Plazomicin and gentamicin were the only drugs demonstrating bactericidal activity towards two of the three Brucella spp., whilst plazomicin was the only drug exhibiting bactericidal activity against B. suis. This is the first study to assess the bactericidal nature of plazomicin against Brucella spp. in vitro. © 2014 Elsevier B.V. and the International Society of Chemotherapy.

Wadhwa A.,University of Tennessee at Knoxville | Bannantine J.P.,Bacterial Diseases of Livestock Research Unit | Byrem T.M.,Antel BioSystems | Stein T.L.,Antel BioSystems | And 3 more authors.
Foodborne Pathogens and Disease | Year: 2012

Johne's disease (JD) or paratuberculosis, caused by Mycobacterium avium ssp. paratuberculosis (MAP), is one of the most economically important diseases of dairy cattle. Control of JD could be achieved by good herd management practices, and diagnosis; however, this approach has been hampered by the low sensitivity of currently available enzyme-linked immunosorbent assay (ELISA) tests. In our previous study, we developed a sensitive serum ELISA test, ethanol-vortex enzyme-linked immunosorbent assay (EVELISA), using ethanol extract of MAP. The objective of this study is to demonstrate that the EVELISA can be used for detection of anti-MAP antibodies in milk samples. In this study, we tested and optimized concentrations of antigen, milk, and secondary antibody for better differentiation of milk samples of cattle with MAP infections from those of cattle in JD-free herds. We evaluated five environmental mycobacteria as absorbents of cross-reactive antibodies in milk and found that the mycobacteria had no significant effect on EVELISA results. Using the optimized conditions, a total of 57 milk samples from Holstein dairy cattle (37 animals found positive on the fecal polymerase chain reaction test and 20 animals from JD-free herds) were tested for anti-MAP antibody in milk by using the EVELISA method. The average of ELISA values in the JD-positive milk samples (mean±SD=0.355±0.455) was significantly higher than that in the JD-negative milk samples (mean±SD=0.071±0.011). These results warrant further studies for evaluation and validation of the EVELISA for milk testing of cattle for JD. © Copyright 2012, Mary Ann Liebert, Inc.

Schuller S.,University of Bern | Francey T.,University of Bern | Hartmann K.,Ludwig Maximilians University of Munich | Hugonnard M.,VetAgro Sup | And 3 more authors.
Journal of Small Animal Practice | Year: 2015

Leptospirosis is a zoonotic disease with a worldwide distribution affecting most mammalian species. Clinical leptospirosis is common in dogs but appears to be rare in cats. Both dogs and cats, however, can shed leptospires in the urine. This is problematic as it can lead to exposure of humans. The control of leptospirosis, therefore, is important not only from an animal but also from a public health perspective. The aim of this consensus statement is to raise awareness of leptospirosis and to outline the current knowledge on the epidemiology, clinical features, diagnostic tools, prevention and treatment measures relevant to canine and feline leptospirosis in Europe. © 2015 British Small Animal Veterinary Association.

Plumb G.E.,National Park Service | Olsen S.C.,Bacterial Diseases of Livestock Research Unit | Buttke D.,Federal office of Public Health of Fribourg
OIE Revue Scientifique et Technique | Year: 2013

Brucellosis is an ancient disease with host-specific evolutionary mechanisms that allow it to hide from or manipulate cellular immunity and achieve intracellular persistence. The disease yields low fatality rates but can cause substantial disabilities. Zoonotic brucellosis remains widespread and neglected in many areas despite notable advances in science, technology, and management in the 19th and 20th Centuries. The burden appears to remain greatest, and yet most under-prioritised globally, amongst pastoral peoples and small-scale livestock farmers. Capacity building for zoonotic brucellosis diagnosis, surveillance, management, and treatment in developing countries faces numerous challenges. Adaptive risk management can provide a framework to build stakeholder support for addressing the complexities and uncertainties, and learning from management actions. The challenges and opportunities for brucellosis management must be recognised as fundamentally multivariate, multifaceted, and integrative; it is thus crucial for veterinary, public health, and wildlife/conservation professions to collaboratively develop, adopt and promulgate a brucellosis One Health paradigm.

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