Veterinary Medicine Commons^™

Human Granulocytic Ehrlichiosis In Europe: Clinical And Laboratory Findings For Four Patients From Slovenia, Stanka Lotric-Furlan, Miroslav Petrovec, Tatjana Avsic Zupanc, William L. Nicholson, John W. Sumner, James E. Childs, Franc Strle

Zoonotics and Wildlife Disease: Publications

Febrile illnesses following a tick bite in patients from Slovenia were evaluated for an ehrlichial etiology. A case of acute human granulocytic ehrlichiosis (HGE) was confirmed by seroconversion to the HGE agent or molecular identification of ehrlichial organisms. Acute infection with the HGE agent was confirmed in four patients. None of the patients had detectable antibodies to the HGE agent at their first visit, but polymerase chain reaction analysis was positive for three patients. All four patients subsequently seroconverted to the HGE agent as shown by high titers of antibody. Clinical features and laboratory findings were similar to those in …

Ecologic Studies Of Rodent Reservoirs: Their Relevance For Human Health, James N. Mills, James E. Childs

Zoonotics and Wildlife Disease: Publications

Within the past few years, the number of “new” human diseases associated with small-mammal reservoirs has increased dramatically, stimulating renewed interest in reservoir ecology research. A consistent, integrative approach to such research allows direct comparisons between studies, contributes to the efficient use of resources and data, and increases investigator safety. We outline steps directed toward understanding vertebrate host ecology as it relates to human disease and illustrate the relevance of each step by using examples from studies of hosts associated with rodent-borne hemorrhagic fever viruses.

Serologic Evidence Of Infection With Ehrlichia Spp. In Wild Rodents (Muridae: Sigmodontinae) In The United States, William L. Nicholson, Susie Muir, John W. Sumner, James E. Childs

Zoonotics and Wildlife Disease: Publications

Rodent (Muridae: Sigmodontinae) blood and sera collected from 14 states were tested for seroreactivity to a cultured isolate of the human granulocytic ehrlichiosis (HGE) agent by using an indirect immunofluorescence assay. Of the 1,240 samples tested, 136 (11%) were found to be reactive at titers of ≥32. Rodents with HGE agent-specific antibodies were found in New York (23% of 491 samples; geometric mean endpoint titer GMT = 441), Connecticut (11% of 100 samples; GMT = 481), California (9% of 32 samples; GMT = 323), Colorado (2% of 212 samples; GMT = 256), Florida (7% of 27 samples; GMT = 362), …

Dietary Habits Of The Common Rodents In An Agrecosystem In Argentina, Barbara A. Ellis, James N. Mills, Gregory E. Glass, Kelly T. Mckee Jr, Delia A. Enria, James E. Childs

Zoonotics and Wildlife Disease: Publications

Dietary habits of five common rodents in agroecosystems on the central Argentine Pampa were studied for 15 months using microhistological analysis of stomach contents. All five rodent species were omnivorous, but proportions of major dietary items (arthropods, dicot leaves and seeds, monocot leaves and seeds) varied among species and seasons. Akodon azarae largely was entomophagous; arthropods formed 41-62% of the diet in all seasons. The other four species (Calomys musculinus, Calomys laucha, Bolomys obscurus, and Oligoryzomys flavescens) consumed most diet items throughout the year, but relative proportions varied among seasons. Leaves formed a relatively minor proportion of the …

Monoclonal Antibody F89/160.1.5 Defines A Conserved Epitope On The Ruminant Prion Protein, Katherine I. O'Rourke, Timothy V. Baszler, Janice M. Miller, Terry R. Spraker, Ingrid Sadler-Riggleman, Donald P. Knowles

Zoonotics and Wildlife Disease: Publications

The transmissible spongiform encephalopathies are a heterogeneous group of fatal neurodegenerative disorders occurring in humans, mink, cats, and ruminant herbivores. The occurrence of novel transmissible spongiform encephalopathies in cattle in the United Kingdom and Europe and in mule deer and elk in parts of the United States has emphasized the need for reliable diagnostic tests with standardized reagents. Postmortem diagnosis is performed by histologic examination of brain sections from affected animals. The histopathological criteria for transmissible spongiform encephalopathies include gliosis, astrocytosis, neuronal degeneration, and spongiform change. These lesions vary in intensity and anatomic location depending on the host species and …

Preclinical Detection Of PrpSc In Nictitating Membrane Lymphoid Tissue Of Sheep, Katherine I. O'Rourke, T. V. Baszler, S. M. Parish, D. P. Knowles

Zoonotics and Wildlife Disease: Publications

SHEEP scrapie is the prototype of a heterogeneous group of transmissible spongiform encephalopathies (TSES) which occur in humans, cattle, cats, mink and cervids. TSEs are characterised by the deposition of prion proteins (Prp-Scrapie or Prp^Sc) in the central nervous system of affected individuals (Prusiner 1982). PrP^Sc and infectivity have also been detected in the lymphoreticular system of sheep well before symptoms occur (Hadlow and others 1982, Race and others 1992). Detection of Prp^Sc in lymphoid tissue, such as tonsils or peripheral lymph nodes, has been proposed as a preclinical diagnostic test for scrapie (Ikegami and others …

Prp Genotypes And Experimental Scrapie In Orally Inoculated Suffolk Sheep In The United States, Katherine I. O'Rourke, G. R. Holyoak, W. W. Clark, J. R. Mickelson, S. Wang, R. P. Melco, T. E. Besser, W. C. Foote

Zoonotics and Wildlife Disease: Publications

One-hundred and three United States Suffolk sheep were inoculated orally with a scrapie agent preparation and monitored for clinical disease and histopathological lesions characteristic of scrapie. A retrospective study of the polymorphisms at codon 171 of the prion protein (PrP) gene was performed on these sheep. All 63 sheep that developed scrapie during the observation period were homozygous for the glutamine 171 (171-QQ) PrP allele. Twelve 171-QQ sheep failed to develop disease. All 5 sheep homozygous for arginine (171-RR) and all 23 heterozygous (171-QR) sheep remained free of scrapie.

Spongiform Encephalopathy In Free-Ranging Mule Deer (Odocoileus Hemionus), White-Tailed Deer (Odocoileus Virginianus) And Rocky Mountain Elk (Cervus Elaphus Nelsoni) In Northcentral Colorado, T. R. Spraker, M. W. Miller, E. S. Williams, D. M. Getzy, W. J. Adrian, G. G. Schoonveid, R. A. Spowart, Katherine I. O'Rourke, J. M. Miller, P. A. Merz

Zoonotics and Wildlife Disease: Publications

Between March 1981 and June 1995, a neurological disease characterized histologically by spongiform encephalopathy was diagnosed in 49 free-ranging cervids from northcentral Colorado (USA). Mule deer (Odocoileus hemionus) were the primary species affected and accounted for 41(84%) of the 49 cases, but six Rocky Mountain elk (Cereus elaphus nelsoni) and two white-tailed deer (Odocoileus virginianus) were also affected. Clinical signs included emaciation, excessive salivation, behavioral changes, ataxia, and weakness. Emaciation with total loss of subcutaneous and abdominal adipose tissue and serous atrophy of remaining fat depots were the only consistent gross findings. Spongiform encephalopathy …

Current Issues In Rabies Prevention In The United States: Health Dilemmas, Public Coffers, Private Interests, Charles E. Rupprecht, Jean S. Smith, John Krebs, Michael Niezgoda, James E. Childs

Zoonotics and Wildlife Disease: Publications

Over the last 100 years, rabies in the United States has changed dramati~ally. More than 90% of all animal rabies cases reported annually to the CDC now occur in wildlife, whereas before 1960 the majority were in domestic animals. The principal rabies hosts today are wild carnivores and bats infected with several viral variants. Annual human deaths have fallen from more than a hundred at the turn of the century to one to two per year despite major outbreaks of animal rabies in several geographic areas. Modem day prophylaxis has proven nearly 100% successful; most human fatalities now occur in …

Virulent Footrot : Mild Or Severe?, Laurie Depiazzi

Journal of the Department of Agriculture, Western Australia, Series 4

The footrot eradication scheme in Western Australia has resulted in a low prevalence of severe footrot.

To appreciate the achievement, we need to understand what exactly is being eradicated. 'S' strains of Dichelorbacter nodosus, the infectious bacterium of footrot, are the target of footrot eradication. Laurie Depiazzi examines the basis for eradicating 'S' strains.

Microevolutionary Patterns And Molecular Markers: The Genetics Of Geographic Variation In Ascaris Suum, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Molecular markers have been used only rarely to characterize the population genetic structure of nematodes. Published studies have suggested that different taxa may show distinct genetic architectures. Isoenzyme and RAPD markers have been used to investigate geographic variation of Ascaris suum at the level of infrapopulations (nematodes within individual hosts), within localities, and among geographic regions. Independent estimates of genetic differentiation among population samples based on isoenzyme and RAPD data showed similar patterns and substantial correlation. Heterozygote deficiencies within infrapopulations and large values for inbreeding coefficients among infrapopulations suggested that the composition of these populations was not consistent with a …

Infections Associated With Bartonella Species In Persons Infected With Human Immunodeficiency Virus, Russell L. Regnery, James E. Childs, Jane E. Koehler

Zoonotics and Wildlife Disease: Publications

Two members of the genus Bartonella, Bartonella quintana (formerly Rochalimaea quintana) and Bartonella henselae (formerly Rochalimaea henselae), have recently been recognized as agents of severe or fatal disease in patients infected with human immunodeficiencyv irus (HIV). The development of infection with B. henselae in HIV-infected individuals has been associated with traumatic contact with cats (scratches or bites), and domestic cats have been identified as a major reservoir for this organism. Specific information regarding the transmission of B. henselae to humans is not yet available, but common-sense precautions that minimize exposure to cat-associated organisms are appropriate. Preliminary accounts suggest that …

Rabies--Epidemiology, Prevention, And Future Research, John W. Krebs, Mark L. Wilson, James E. Childs

Zoonotics and Wildlife Disease: Publications

Rabies is caused by a single-stranded, negative-sense RNA virus, maintained in nature by a variety of animal reservoirs. Rabies virus infects the central nervous system, resulting in progressive encephalopathy and ultimately death in an infected human. Globally, the risk of contracting rabies for humans is greatest in regions of the developing world where dog rabies is enzootic. Where rabies in dogs has been eliminated or otherwise controlled through vaccination programs, the disease can be maintained by wildlife. Wildlife primarily involved in maintenance of transmission cycles are carnivores and bats. Persons having frequent contact with wildlife, such as mammalogists, are at …

Rodent-Borne Hemorrhagic Fever Viruses: A Special Risk For Mammalogists?, James E. Childs, James N. Mills, Gregory E. Glass

Zoonotics and Wildlife Disease: Publications

We review two groups of taxonomically unrelated viruses that share similarities in host preference and transmission routes to humans and pose a risk for mammalogists working with rodents. The rodent-borne hemorrhagic fever viruses in the Arenaviridae and Bunyaviridae are widely distributed on most continents where rodents occur. Their geographic distribution usually exceeds the distribution of the recognized human diseases they cause and has resulted from either natural coevolutionary events or the dissemination of viral passengers traveling with introduced mammalian hosts. Diseases of humans caused by these agents are among the most severe and most frequently fatal of zoonotic diseases. These …

A Case-Control Study Of Hantavirus Pulmonary Syndrome During An Outbreak In The Southwestern United States, Paul S. Zeitz, Jay C. Butler, James E. Cheek, Michael C. Samuel, James E. Childs, Lee A. Shands, Richard E. Turner, Ronald E. Voorhees, John Sarisky, Pierre E. Rollin, Thomas G. Ksiazek, Louisa Chapman, Susan E. Reef, Kenneth K. Komatsu, Craig Dalton, John W. W. Krebs, Gary O. Maupin, Kenneth Gage, C. Mack Sewell, Robert F. Breiman, C. J. Peters

Zoonotics and Wildlife Disease: Publications

In May 1993, an outbreak of hantavirus pulmonary syndrome( HPS) occurred in the south-western United States. A case-control study determined risk factors for HPS. Seventeen case-patients were compared with 3 groups of controls: members of case-patient households( household controls), members of neighboring households( near controls), and members of randomly selected households ≥ 24 km away ( far controls). Investigators trapped more small rodents at case households than at near ( P = .03) or far control households( P = .02). After the number of small rodents was controlled for,case-patients were more likely than household controls to hand plow (odds ratio …

Guidelines For Working With Rodents Potentially Infected With Hantavirus, James N. Mills, Terry L. Yates, James E. Childs, Robert R. Parmenter, Thomas G. Ksiazek, Pierre E. Rollin, C.J. Peters

Zoonotics and Wildlife Disease: Publications

Because of the high morbidity and mortality associated with hantavirus pulmonary syndrome and the possibility of aerosol transmission of hantaviruses, persons handling known reservoir species in the field, laboratory, or classroom should take special precautions to minimize the risk of infection. We provide specific guidelines for personal safety while trapping, handling and releasing, transporting, sampling, and performing necropsy on potentially infected rodents or teaching field classes in areas occupied by reservoir species. Special consideration should be given to respiratory protection, choice and use of disinfectants, decontamination of instruments and traps, proper disposal of infectious wastes, and preservation and shipment of …

Quality Wool Production At Lower Cost, Peter Metcalfe

Journal of the Department of Agriculture, Western Australia, Series 4

Low wool prices are forcing farmers to reduce their sheep management costs but, fortunately, cost cutting is not resulting in lower wool production, poorer wool quality or lessened sheep care on the best wool growing properties.

Serologic And Genetic Identification Of Peromyscus Maniculatus As The Primary Rodent Reservoir For A New Hantavirus In The Southwestern United States, James E. Childs, Thomas G. Ksiazek, Christina F. Spiropoulou, John W. Krebs, Sergey Morzunov, Gary O. Maupin, Kenneth L. Gage, Pierre E. Rollin, John Sarisky, Russell E. Enscore, Jennifer K. Frey, C. J. Peters, Stuart T. Nichol

Zoonotics and Wildlife Disease: Publications

An outbreak of hantavirus pulmonary syndrome(H PS) in the southwestern United States was etiologically linked to a newly recognized hantavirus. Knowledge that hantaviruses are maintained in rodent reservoirs stimulated a field and laboratory investigation of 1696 small mammals of 31 species. The most commonly captured rodent, the deer mouse( Peromyscus maniculatus), had the highest antibody prevalence(3 %)to four hantavirus antigens. Antibody also was detected in 10 other species of rodent and in 1 species of rabbit. Reverse transcriptase-polymerase chain reaction( RT-PCR)products of hantavirus from rodent tissues were indistinguishable from those from human H PS patients. More than 96% of …

White-Tailed Deer As A Potential Reseroir Of Ehrlichia Spp., Jacqueline E. Dawson, James E. Childs, Kristine L. Biggie, Charla Moore, David Stalknecht, John Shaddock, John Bouseman, Erik Hofmeister, James G. Olson

Zoonotics and Wildlife Disease: Publications

We determined the antibody prevalence to Ehrlichia spp., in white-tailed deer (Odocoileus virginianus) and the geographic distribution of seropositive animals in 84 counties in Alabama, Arkansas, Florida, Georgia, Illinois, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia (USA). Using an indirect fluorescent antibody test we detected antibodies (≥ 1:128) to this bacterium in 544 (43%) of 1269 deer. Presence of antibodies to Ehrlichia spp. was related to a southerly latitude, low elevation, and resulting milder climatic conditions. It appears that whitetailed deer were naturally infected with Ehrlichia spp.; the infection …

Expression Of Functional Protease And Subviral Particles By Vaccinia Virus Containing Equine Infectious Anaemia Virus Gag And 5' Pol Genes, Travis C. Mcguire, Katherine I. O'Rourke, Timothy V. Baszler, Steven R. Leib, Alberta L. Brassfield, William C. Davis

Zoonotics and Wildlife Disease: Publications

Cells infected with vaccinia viruses expressing the equine infectious anaemia virus (EIAV) gag gene (VGag) or gag plus the 5' pol encoding protease (VGag/PR) were evaluated with monoclonal antibody to a p26 capsid protein linear epitope (QEISKFLTD). Both recombinant viruses expressed Gag precursor protein (55K) whereas only VGag/PR expressed a detectable Gag-Pol fusion protein (82K) with a functional protease, shown by subviral particles containing processed p26. Horses inoculated with VGag/PR produced antibodies reactive with EIAV Gag proteins.

Scid Mouse Spleen Does Not Support Scrapie Agent Replication, Katherine I. O'Rourke, T. P. Huff, C. W. Leathers, M. M. Robinson, J. R. Gorham

Zoonotics and Wildlife Disease: Publications

BALB/c and severe combined immunodeficiency (SCID) mice were inoculated intracerebrally or intraperitoneally with scrapie agent strain ME7 to examine the role of functional lymphocytes and follicular dendritic cells in splenic infectivity and PrP^sc accumulation. Intracerebrally inoculated BALB/c and SCID mice developed the clinical signs and microscopic lesions characteristic of scrapie. Spleens from terminally affected BALB/c mice contained PrP^sc which was detectable by immunoblot analysis; SCID mouse spleens did not contain detectable PrP so. SCID mouse spleens collected during the first 90 days after intraperitoneal infection contained neither infectivity nor PrP^sc.

Major Histocompatibility Complex-Restricted Cd8+ Cytotoxic T Lymphocytes From Horses With Equine Infectious Anemia Virus Recognize Env And Gag/Pr Proteins, Travis C. Mcguire, Daniel B. Tumas, Katherine M. Byrne, Melissa T. Hines, Steven R. Leib, Alberta L. Brassfield, Katherine I. O'Rourke, Lance E. Perryman

Zoonotics and Wildlife Disease: Publications

Cytotoxic T lymphocytes (CTL) can control some viral infections and may be important in the control of lentiviruses, including human immunodeficiency virus type 1. Since there is limited evidence for an in vivo role of CTL in control of lentiviruses, dissection of immune mechanisms in animal lentiviral infections may provide needed information. Horses infected with equine infectious anemia virus (EIAV), a lentivirus, have acute plasma viremia which is terminated in immunocompetent horses. Viremic episodes may recur, but most horses ultimately control infection and become asymptomatic carriers. To begin dissection of the immune mechanisms involved in EIAV control, peripheral blood mononuclear …

Miscellaneous Publication No 33/93 - Virulent Footrot A Farmer's Guide To Eradication, Department Of Agriculture, Western Australia

Animal production and livestock published reports

The first thing to understand about virulent footrot is that it can occur on any farm in the medium to high rainfall zone. Persons who regularly buy and sell sheep have a greater risk, but even closed breeding flock properties are at risk from stray sheep.

People often associate footrot with properties managed by inefficient farmers. This is a false belief. Many good farmers have found the disease in their sheep, including high profile studs.

Footrot can strike anywhere and often without warning.

The important thing to remember is that once it is found, getting to know and understand the …

Do Farmers Really Want To Eradicate Sheep Lice?, Chris Hawkins

Journal of the Department of Agriculture, Western Australia, Series 4

With the termination of Western Australia's Sheep Lice Eradication Campaign in 1993 farmers' views about the eradication of sheep lice are of greater relevance now than in the past. Lice control now rests with individual farmers and continuing local lice cell groups .

A recent survey of producers in the Moora Shire provides some key insights into farmers' thoughts about sheep lice and their eradication.

Genetic Identificationo F A Hantavirusa Ssociated With An Outbreako F Acute Respiratoryi Llness, Stuart T. Nichol, Christina F. Spiropoulou, Sergey Morzunov, Pierre E. Rollin, Thomas G. Ksiazek, Heinz Feldmann, Anthony Sanchez, James E. Childs, Sherif Zaki, Clarence J. Peters

Zoonotics and Wildlife Disease: Publications

A mysterious respiratory illness with high mortality was recently reported in the southwestern United States. Serologic studies implicated the hantaviruses, rodent-borne RNA viruses usually associated elsewhere in the world with hemorrhagic fever with renal syndrome. A genetic detection assay amplified hantavirus-specific DNA fragments from RNA extracted from the tissues of patients and deer mice (Peromyscus maniculatus) caught at or near patient residences. Nucleotide sequence analysis revealed the associated virus to be a new hantavirus and provided a direct genetic link between infection in patients and rodents.

Infection With A Ratborne Hantavirus In Us Residents Is Consistently Associated With Hypertensive Renal Disease, Gregory E. Glass, Alan J. Watson, James W. Leduc, Gabor D. Kelen, Thomas C. Quinn, James E. Childs

Zoonotics and Wildlife Disease: Publications

A survey of 8080 subjects was conducted in Baltimore, examining the association between infection with hantaviruses and renal disease. Two groups (N = 6060) with no known risk factors were selected to establish a baseline antibody prevalence. Overall, antibody prevalence was 0.25%. Seroprevalence increased with age, without sex- or race-related differences. Patients with proteinuria showed the same patterns of infection but were more commonly seropositive (1.46%) than the reference group( OR, 3.23; P < .05). Infection among dialysis patients with end-stage renal disease was 2.76%, significantly higher than in the reference group( OR, 5.03; P < .05). In the proteinuria and the dialysis groups, hantavirus infection was consistently associated with a diagnosis of hypertensive renal disease. The association was unrelated to other chronic renal disease diagnoses. Overall, 6.5% of patients with end-stage renal disease due to hypertension were seropositive for a hantavirus. These data suggest that hantavirus infection is associated with hypertensive renal disease.

Progress Toward Eradication Of Virulent Footrot, Bob Mitchell

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia is well placed to eradicate virulent footrot from the State's sheep and goat populations.

Between 1950 and 1993 the proportion of sheep flocks with footrot fell from about 15 per cent to less than 2 percent, and the 1990-92 outbreak has been turned around. One hundred and eighty properties (]. 7 per cent) of flocks, mostly in the high rainfall South-West, are in quarantine for footrot today.

This high level of footrot control is the result of strong support from the sheep industry and years of good cooperation between farmers and the Department of Agriculture.

Western Australia leads …

Choosing Shower Dips For Sheep Lice, Tony Higgs, Bob Love

Journal of the Department of Agriculture, Western Australia, Series 4

The performance of all shower dip chemicals for sheep lice can vary depending on the active chemical and the conditions under which they are used.

Department of Agriculture trials have indicated that the wettable powders coumaphos and magnesium fluorosilicate were less effective at eradicating sheep lice than were synthetic pyrethroid and organophosphate dipping chemicals.

However, failure to eradicate sheep lice may be the result of several factors, many of them related to management.

Reproductive Characteristics Of Rodent Assemblages In Cultivated Regions Of Central Argentina, James N. Mills, Barbara A. Ellis, Kelly T. Mckee, Julio I. Maiztegui, James E. Childs

Zoonotics and Wildlife Disease: Publications

Small mammals were trapped for 2 years at 16 localities on the central-Argentine pampa. Six species (Akodon azarae, Calomys musculinus, C. laucha, Bolomys obscurus, Oligory-zomys flavescens and Mus musculus) accounted for >95% of captures. The major breeding season, as assessed by pregnancies, was September or October through April or May. Mild weather in late autumn and winter of the second season resulted in a relatively longer breeding season during the 2nd year of the study. Females of all six species comprised significantly 50% of captures during the height of the breeding season. For most species, there was …

Habitat Associations And Relative Densities Of Rodent Populations In Cultivated Areas Of Central Argentina, James N. Mills, Barbara A. Ellis, Kelly T. Mckee, Julio I. Maiztegui, James E. Childs

Zoonotics and Wildlife Disease: Publications

Small mammals were livetrapped during 12 months in crop fields and weedy borders at 18 sites in central Argentina. A total of 1,652 mammals of 14 species was captured during3 3,060 trap-nights. Six species of rodents comprised > 95% of captures. Periodically disturbed fields of crops were dominated by Calomys musculinus and C. laucha, and to a lesser extent Mus musculus. A second group composed of Akodon azarae, Bolomys obscures, and Oligoryzomys flavescens primarily inhabited the more stable, weedy borders of cultivated fields. Peaks in relative densities of C. musculinus, C. laucha, and M . musculus …