Lisa L Wolfe

Publications of Lisa L Wolfe

• Assessment of prospective preventive therapies for chronic wasting disease in mule deer.

  Authors: Lisa L Wolfe, David A Kocisko, Byron Caughey, Michael W Miller

  Journal of wildlife diseases. 04/2012; 48(2):530-3.

  We compared prion infection rates among mule deer (Odocoileus hemionus) receiving pentosan polysulfate, tannic acid, tetracycline HCl, or no treatment 14 days before to 14 days after (dpi) oralWe compared prion infection rates among mule deer (Odocoileus hemionus) receiving pentosan polysulfate, tannic acid, tetracycline HCl, or no treatment 14 days before to 14 days after (dpi) oral inoculation with tonsil tissue homogenate. All deer were infected, but the rapid disease course (230-603 dpi) suggested our challenge was overwhelming.

• Survival Patterns in White-tailed and Mule Deer after Oral Inoculation with a Standardized, Conspecific Prion Dose.

  Authors: Michael W Miller, Lisa L Wolfe, Tracey M Sirochman, Michael A Sirochman, Jean E Jewell, Elizabeth S Williams

  Journal of wildlife diseases. 04/2012; 48(2):526-9.

  We orally inoculated white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) with a standardized, conspecific prion dose and collected biologic samples throughout the diseaseWe orally inoculated white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) with a standardized, conspecific prion dose and collected biologic samples throughout the disease course. Mule deer (PRNP genotype 225SS) and PRNP genotype 96GG white-tailed deer succumbed along similar trajectories, but 96GS- and 96SS-genotype individuals tended to survive longer.

• Salivary prions in sheep and deer.

  Authors: Gültekin Tamgüney, Jürgen A Richt, Amir N Hamir, Justin J Greenlee, Michael W Miller, Lisa L Wolfe, Tracey M Sirochman, Alan J Young, David V Glidden, Natrina L Johnson, Kurt Giles, Stephen J Dearmond, Stanley B Prusiner

  Prion. 01/2012; 6(1):52-61.

  Scrapie of sheep and chronic wasting disease (CWD) of cervids are transmissible prion diseases. Milk and placenta have been identified as sources of scrapie prions but do not explain horizontalScrapie of sheep and chronic wasting disease (CWD) of cervids are transmissible prion diseases. Milk and placenta have been identified as sources of scrapie prions but do not explain horizontal transmission. In contrast, CWD prions have been reported in saliva, urine and feces, which are thought to be responsible for horizontal transmission. While the titers of CWD prions have been measured in feces, levels in saliva or urine are unknown. Because sheep produce ~17 L/day of saliva, and scrapie prions are present in tongue and salivary glands of infected sheep, we asked if scrapie prions are shed in saliva. We inoculated transgenic (Tg) mice expressing ovine prion protein, Tg(OvPrP) mice, with saliva from seven Cheviot sheep with scrapie. Six of seven samples transmitted prions to Tg(OvPrP) mice with titers of -0.5 to 1.7 log ID 50 U/ml. Similarly, inoculation of saliva samples from two mule deer with CWD transmitted prions to Tg(ElkPrP) mice with titers of -1.1 to -0.4 log ID 50 U/ml. Assuming similar shedding kinetics for salivary prions as those for fecal prions of deer, we estimated the secreted salivary prion dose over a 10-mo period to be as high as 8.4 log ID 50 units for sheep and 7.0 log ID 50 units for deer. These estimates are similar to 7.9 log ID 50 units of fecal CWD prions for deer. Because saliva is mostly swallowed, salivary prions may reinfect tissues of the gastrointestinal tract and contribute to fecal prion shedding. Salivary prions shed into the environment provide an additional mechanism for horizontal prion transmission.

• Assessment of a recombinant F1-V fusion protein vaccine intended to protect Canada lynx (Lynx canadensis) from plague.

  Authors: Lisa L Wolfe, Tanya M Shenk, Bradford Powell, Tonie E Rocke

  Journal of wildlife diseases. 10/2011; 47(4):888-92.

  As part of an ongoing restoration program in Colorado, USA, we evaluated adverse reactions and seroconversion in captive Canada lynx (Lynx canadensis) after vaccination with a recombinant F1-V fusionAs part of an ongoing restoration program in Colorado, USA, we evaluated adverse reactions and seroconversion in captive Canada lynx (Lynx canadensis) after vaccination with a recombinant F1-V fusion protein vaccine against Yersinia pestis, the bacterium that causes plague. Ten adult female lynx received the F1-V vaccine; 10 source- and age-matched lynx remained unvaccinated as controls. All of the vaccinated and control lynx remained apparently healthy throughout the confinement period. We observed no evidence of injection site or systemic reactions to the F1-V vaccine. Among vaccinated lynx, differences in log(10) reciprocal antibody titers measured in sera collected before and after vaccination (two doses) ranged from 1.2 to 5.2 for anti-F1 antibodies and from 0.6 to 5.2 for anti-V antibodies; titers in unvaccinated lynx did not change appreciably over the course of confinement prior to release, and thus differences in anti-F1 (P=0.003) and anti-V (P=0.0005) titers were greater among vaccinated lynx than among controls. Although our findings suggest that the F1-V fusion protein vaccine evaluated here is likely to stimulate antibody responses that may help protect Canada lynx from plague, we observed no apparent differences in survival between vaccinated and unvaccinated subject animals. Retrospectively, 22 of 50 (44%; 95% confidence interval 29-59%) unvaccinated lynx captured or recaptured in Colorado during 2000-08 had passive hemagglutination antibody titers >1:16, consistent with exposure to Y. pestis; paired pre- and postrelease titers available for eight of these animals showed titer increases similar in magnitude to those seen in response to vaccination, suggesting at least some lynx may naturally acquire immunity to plague in Colorado habitats.

• Pasteurellaceae from Colorado bighorn sheep herds.

  Authors: Michael W Miller, Lisa L Wolfe

  Journal of wildlife diseases. 07/2011; 47(3):800-4.

  We compared phenotypic and genotypic characterizations of 88 Pasteurellaceae isolates from bighorn sheep (Ovis canadensis) in the course of exploring epizootiologic relationships. Based on ourWe compared phenotypic and genotypic characterizations of 88 Pasteurellaceae isolates from bighorn sheep (Ovis canadensis) in the course of exploring epizootiologic relationships. Based on our observations, adopting contemporary taxonomic conventions and using molecular methods to detect and compare Pasteurellaceae may help improve understanding of bighorn respiratory disease epizootiology and management.

• Failure of fallow deer (Dama dama) to develop chronic wasting disease when exposed to a contaminated environment and infected mule deer (Odocoileus hemionus).

  Authors: Jack C Rhyan, Michael W Miller, Terry R Spraker, Matt McCollum, Pauline Nol, Lisa L Wolfe, Tracy R Davis, Lynn Creekmore, Katherine I O'Rourke

  Journal of wildlife diseases. 07/2011; 47(3):739-44.

  We monitored a herd of fallow deer (Dama dama) for evidence of prion infection for 7 yr by periodic postmortem examination of animals from the herd. The fallow deer were exposed to the chronicWe monitored a herd of fallow deer (Dama dama) for evidence of prion infection for 7 yr by periodic postmortem examination of animals from the herd. The fallow deer were exposed to the chronic wasting disease (CWD) agent from mule deer by living in a paddock considered contaminated with infectivity from its history of housing CWD infected deer and, after the first year of the study, by comingling with infected mule deer (Odocoileus hemionus). At least 8 of 12 mule deer serving as sentinels for prion transmission and 25 additional mule deer serving as sources of infectivity developed clinical CWD or were otherwise confirmed to be infected with CWD via lymphoid tissue immunohistochemistry (IHC). In contrast, none of the 41 exposed fallow deer showed clinical signs suggestive of CWD, IHC staining of disease-associated prion in lymphoid or brain tissues, or evidence of spongiform degeneration in sections of brain stem at the level of the obex when sampled 18 mo to 7 yr after entering the mule deer paddock. The absence of clinical disease and negative IHC results in fallow deer housed in the same contaminated paddock for up to 7 yr and almost continuously exposed to CWD-infected mule deer for up to 6 yr suggests a species barrier or other form of resistance preventing fallow deer infection by the CWD agent or delaying progression of the disease in this species.

• A bighorn sheep die-off in southern Colorado involving a Pasteurellaceae strain that may have originated from syntopic cattle.

  Authors: Lisa L Wolfe, Brandon Diamond, Terry R Spraker, Michael A Sirochman, Daniel P Walsh, Chandra M Machin, Donald J Bade, Michael W Miller

  Journal of wildlife diseases. 10/2010; 46(4):1262-8.

  We investigated a pasteurellosis epizootic in free-ranging bighorn sheep (Ovis canadensis) wherein a Pasteurellaceae strain carried by syntopic cattle (Bos taurus) under severe winter conditionsWe investigated a pasteurellosis epizootic in free-ranging bighorn sheep (Ovis canadensis) wherein a Pasteurellaceae strain carried by syntopic cattle (Bos taurus) under severe winter conditions appeared to contribute to pneumonia in affected bighorns. Twenty-one moribund or dead bighorn sheep were found on the "Fossil Ridge" herd's winter range, Colorado, USA, between 13 December 2007 and 29 February 2008. Eight carcasses examined showed gross or microscopic evidence of acute to subacute fibrinous bronchopneumonia. All eight carcasses yielded at least one β-hemolytic Mannheimia haemolytica biogroup 1(±(G)) strain, and seven also yielded a β-hemolytic Bibersteinia trehalosi biogroup 4 (CDS) strain; evidence of Pasteurella multocida, Mycoplasma ovipneumoniae, and parainfluenza 3 and bovine respiratory syncytial viruses was also detected. Isolates of β-hemolytic Manneimia haemolytica biogroup 1(G) from a bighorn carcass and a syntopic cow showed 99.5% similarity in genetic fingerprints; B. trehalosi biogroup 4(CDS) isolates were ≥94.9% similar to an isolate from a nearby bighorn herd. Field and laboratory observations suggested that pneumonia in affected bighorns may have been caused by a combination of pathogens including two pathogenic Pasteurellaceae strains--one likely of cattle origin and one likely of bighorn origin--with infections in some cases perhaps exacerbated by other respiratory pathogens and severe weather conditions. Our and others' findings suggest that intimate interactions between wild sheep and cattle should be discouraged as part of a comprehensive approach to health management and conservation of North American wild sheep species.

• Asymptomatic deer excrete infectious prions in faeces.

  Authors: Gültekin Tamgüney, Michael W Miller, Lisa L Wolfe, Tracey M Sirochman, David V Glidden, Christina Palmer, Azucena Lemus, Stephen J DeArmond, Stanley B Prusiner

  Nature. 07/2010; 466(7306):652.

• Select tissue mineral concentrations and chronic wasting disease status in mule deer from North-central Colorado.

  Authors: Lisa L Wolfe, Mary M Conner, Cathy L Bedwell, Paul M Lukacs, Michael W Miller

  Journal of wildlife diseases. 07/2010; 46(3):1029-34.

  Trace mineral imbalances have been suggested as having a causative or contributory role in chronic wasting disease (CWD), a prion disease of several North American cervid species. To begin exploringTrace mineral imbalances have been suggested as having a causative or contributory role in chronic wasting disease (CWD), a prion disease of several North American cervid species. To begin exploring relationships between tissue mineral concentrations and CWD in natural systems, we measured liver tissue concentrations of copper, manganese, and molybdenum in samples from 447 apparently healthy, adult (> or = 2 yr old) mule deer (Odocoileus hemionus) culled or vehicle killed from free-ranging populations in north-central Colorado, United States, where CWD occurs naturally; we also measured copper concentrations in brain-stem (medulla oblongata at the obex) tissue from 181 of these deer. Analyses revealed a wide range of concentrations of all three minerals among sampled deer (copper: 5.6-331 ppm in liver, 1.5-31.9 ppm in obex; manganese: 0.1-21.4 ppm in liver; molybdenum: 0.5-4.0 ppm in liver). Bayesian multiple regression analysis revealed a negative association between obex copper (-0.097; 95% credible interval -0.192 to -0.006) and the probability of sampled deer also being infected with CWD, as well as a positive association between liver manganese (0.158; 95% credible interval 0.066 to 0.253) and probability of infection. We could not discern whether the tendencies toward lower brain-stem copper concentrations or higher systemic manganese concentrations in infected deer preceded prion infection or rather were the result of infection and its subsequent effects, although the distribution of trace mineral concentrations in infected deer seemed more suggestive of the latter.

• Detection of Yersinia pestis DNA in prairie dog-associated fleas by polymerase chain reaction assay of purified DNA.

  Authors: Karen A Griffin, Daniel J Martin, Laura E Rosen, Michael A Sirochman, Daniel P Walsh, Lisa L Wolfe, Michael W Miller

  Journal of wildlife diseases. 04/2010; 46(2):636-43.

  We evaluated, refined, and applied well-established polymerase chain reaction (PCR) techniques for detecting Yersinia pestis DNA in fleas (mainly Oropsylla spp.) collected from prairie dog (CynomysWe evaluated, refined, and applied well-established polymerase chain reaction (PCR) techniques for detecting Yersinia pestis DNA in fleas (mainly Oropsylla spp.) collected from prairie dog (Cynomys spp.) burrows. Based on results from PCR of avirulent Y. pestis strain A1122 DNA, we used DNA purification and primers for the plasminogen activator gene to screen field-collected fleas. We detected Y. pestis DNA in flea pools from two black-tailed prairie dog (Cynomys ludovicianus) colonies with evidence of recent plague epizootics, and from one of four white-tailed prairie dog (Cynomys leucurus) colony complexes (Wolf Creek) where evidence of epizootic plague was lacking. Relative flea abundance and occurrence of Y. pestis DNA among flea pools appeared to vary over time at Wolf Creek. Both DNA purification and primer sequences appeared to influence the likelihood of detecting Y. pestis DNA by PCR in fleas collected from prairie dog burrows in the absence of observed epizootic plague. Presence of Y. pestis plasmid DNA in fleas collected from prairie dog burrows at Wolf Creek may represent evidence that infected fleas were somehow being maintained in that system between epizootics, consistent with the hypothesized enzootic maintenance of plague in prairie dog colony complexes elsewhere.

• Effects of selenium supplementation and sample storage time on blood indices of selenium status in bighorn sheep.

  Authors: Laura E Rosen, Daniel P Walsh, Lisa L Wolfe, Cathy L Bedwell, Michael W Miller

  Journal of wildlife diseases. 08/2009; 45(3):795-801.

  Periodic pneumonia outbreaks cause large-scale die-offs that threaten the viability of bighorn sheep (Ovis canadensis) populations. Bighorns are highly susceptible to pneumonia, and in some casesPeriodic pneumonia outbreaks cause large-scale die-offs that threaten the viability of bighorn sheep (Ovis canadensis) populations. Bighorns are highly susceptible to pneumonia, and in some cases this susceptibility may be exacerbated by trace mineral deficiencies. To evaluate responses to injectable selenium supplementation, eight captive bighorn sheep were treated with either an injectable sodium selenite supplement or a saline control. We collected 6-ml blood aliquots before and at 1, 6, and 12 wk posttreatment. We submitted one set of aliquots immediately to measure selenium (Se) and zinc (Zn) concentrations and glutathione-peroxidase (GSH-Px) activity; additional aliquots were held at about 22 C and then submitted at 1, 3, and 7 days postcollection to assess effects of storage on these measures. Neither Se nor GSH-Px were affected by selenite injections. Both Se and GSH-Px demonstrated small linear decays over the 7-day storage period (0.011 ppm/day [SE=0.0027] and 15.78 mmole/l/sec/day [SE=6.88], respectively); in contrast, Zn concentrations in stored samples increased logarithmically (0.35 ppm/day on the natural log scale). Blood Se and GSH-Px were not correlated in sampled bighorns; however, because all values for both measures were within normal limits, lack of correlation did not affect interpretation of these data in our study.

• Evaluation of intramuscular butorphanol, azaperone, and medetomidine and nasal oxygen insufflation for the chemical immobilization of white-tailed deer, Odocoileus virginianus.

  Authors: Patrice M Mich, Lisa L Wolfe, Tracey M Sirochman, Michael A Sirochman, Tracy R Davis, William R Lance, Michael W Miller

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 10/2008; 39(3):480-7.

  Chemical immobilization of wildlife often includes opioids or cyclohexamines. These substances are problematic as a result of their required storage, handling, and record-keeping protocols. AChemical immobilization of wildlife often includes opioids or cyclohexamines. These substances are problematic as a result of their required storage, handling, and record-keeping protocols. A potentially useful alternative sedation protocol includes a combination of butorphanol, azaperone, and medetomidine (BAM: 0.43 mg/kg butorphanol, 0.36 mg/kg azaperone, 0.14 mg/kg medetomidine). One risk of wildlife immobilization with any drug combination is hypoxemia. This may be of particular importance when using an alpha 2 agonist such as medetomidine because of its powerful vasoconstrictive effect. In this prospective study, the BAM combination was evaluated for chemical immobilization of white-tailed deer. Additionally, selected physiologic parameters associated with BAM immobilization, including oxygen saturation via pulse oximetry and arterial blood gas measurement, with and without nasal insufflation of oxygen at a relatively low flow of 3 L/min, were evaluated. The BAM combination resulted in a predictable onset of sedation, with a mean induction time to lateral recumbency of 9.8 +/- 3.6 min. All deer recovered smoothly within a range of 5-20 min after reversal with intramuscular administration of naltrexone, atipamazole, and tolazoline (NAT). Clinically relevant decreases in arterial partial pressure of oxygen (PaO2) and oxygen saturation (SpO2) were observed in animals not receiving supplemental oxygen, while both parameters significantly improved for oxygen-supplemented deer. Pulse oximetry with this protocol was an unreliable indicator of oxygen saturation. In this study, altitude, recumbency, hypoventilation, butorphanol- and medetomidine-specific effects, as well as the potential for alpha 2 agonist-induced pulmonary changes all may have contributed to the development of hypoxemia. Overall, capture of white-tailed deer with the BAM/NAT protocol resulted in excellent chemical immobilization and reversal. Because the BAM combination caused significant hypoxemia that is unreliably detected by pulse oximetry but that may be resolved with nasal oxygen insufflation, routine use of oxygen supplementation is recommended.

• Immobilization of black bears (Ursus americanus) with a combination of butorphanol, azaperone, and medetomidine.

  Authors: Lisa L Wolfe, Catherine T Goshorn, Sharon Baruch-Mordo

  Journal of wildlife diseases. 08/2008; 44(3):748-52.

  Sixteen captive and five free-ranging black bears (Ursus americanus) were immobilized with a combination of butorphanol, azaperone, and medetomidine (BAM). The BAM drug combination was premixed usingSixteen captive and five free-ranging black bears (Ursus americanus) were immobilized with a combination of butorphanol, azaperone, and medetomidine (BAM). The BAM drug combination was premixed using 0.5 ml butorphanol (30 mg/ml), 0.25 ml azaperone (50 mg/ml), and 0.25 ml medetomidine (20 mg/ml) per milliliter to yield a final mix of (15 mg butorphanol+12.5 mg azaperone+5 mg medetomidine)/ml. This combination, dosed at 0.4 ml BAM/approximately 23 kg estimated body weight, provided a mean induction time of 10 min (95% confidence interval [CI]=2 min), consistent anesthesia without apparent adverse effects, and smooth recovery (mean=15 min, 95% CI=4 min) after antagonism with atipamezole (5 mg/mg medetomidine) alone or in combination with naltrexone (5 mg/mg butorphanol). Based on our initial observations, BAM appears to be a reversible and accessible drug combination for immobilizing black bears that merits further evaluation for field use.

• Lions and prions and deer demise.

  Authors: Michael W Miller, Heather M Swanson, Lisa L Wolfe, Fred G Quartarone, Sherri L Huwer, Charles H Southwick, Paul M Lukacs

  PLoS ONE. 01/2008; 3(12):e4019.

  BACKGROUND: Contagious prion diseases - scrapie of sheep and chronic wasting disease of several species in the deer family - give rise to epidemics that seem capable of compromising host populationBACKGROUND: Contagious prion diseases - scrapie of sheep and chronic wasting disease of several species in the deer family - give rise to epidemics that seem capable of compromising host population viability. Despite this prospect, the ecological consequences of prion disease epidemics in natural populations have received little consideration. METHODOLOGY/PRINCIPAL FINDINGS: Using a cohort study design, we found that prion infection dramatically lowered survival of free-ranging adult (>2-year-old) mule deer (Odocoileus hemionus): estimated average life expectancy was 5.2 additional years for uninfected deer but only 1.6 additional years for infected deer. Prion infection also increased nearly fourfold the rate of mountain lions (Puma concolor) preying on deer, suggesting that epidemics may alter predator-prey dynamics by facilitating hunting success. Despite selective predation, about one fourth of the adult deer we sampled were infected. High prevalence and low survival of infected deer provided a plausible explanation for the marked decline in this deer population since the 1980s. CONCLUSION: Remarkably high infection rates sustained in the face of intense predation show that even seemingly complete ecosystems may offer little resistance to the spread and persistence of contagious prion diseases. Moreover, the depression of infected populations may lead to local imbalances in food webs and nutrient cycling in ecosystems in which deer are important herbivores.

• Oral papillomatosis in Canada lynx (Lynx canadensis).

  Authors: Lisa L Wolfe, Terry R Spraker

  Journal of wildlife diseases. 10/2007; 43(4):731-3.

  We observed 11 cases of oral papillomatosis among 48 free-ranging Canada lynx (Lynx canadensis) that had been shipped to Colorado for translocation purposes. Lesions were 1-3 mm, multifocal,We observed 11 cases of oral papillomatosis among 48 free-ranging Canada lynx (Lynx canadensis) that had been shipped to Colorado for translocation purposes. Lesions were 1-3 mm, multifocal, nonpigmented sessile masses and occurred on the ventral lingual surface. Adverse clinical signs were not observed. Six of the 11 cases resolved and the remainder appeared to be self-limiting when affected animals were examined <or=4 mo later. New cases did not develop in previously unaffected lynx while in captivity. Histopathologic lesions included marked hyperplasia of the mucosal epithelium causing thickening of the stratum spinosum and corneum. Ballooning degeneration of epithelial cells with intracytoplasmic inclusions were observed. Papilloma virus was found on negative contrast electron microscopy. Papillomatosis was seen in lynx from three geographically distant sources (British Columbia, five of 21 individuals; Quebec, five of 17; Yukon, one of four) suggesting the causative virus may be widespread among North American lynx populations.

• PrPCWD in rectal lymphoid tissue of deer (Odocoileus spp.).

  Authors: Lisa L Wolfe, Terry R Spraker, Lorenzo González, Mark P Dagleish, Tracey M Sirochman, Jeremy C Brown, Martin Jeffrey, Michael W Miller

  The Journal of general virology. 08/2007; 88(Pt 7):2078-82.

  The utility of rectal lymphoid tissue sampling for the diagnosis of chronic wasting disease (CWD) infections in mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) wasThe utility of rectal lymphoid tissue sampling for the diagnosis of chronic wasting disease (CWD) infections in mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) was evaluated. CWD-associated prion protein (PrP(CWD)) deposits were observed in the rectal mucosa from 19 orally inoculated mule deer by 381 days post-inoculation (p.i.); similarly, 45 out of 50 naturally infected mule deer had PrP(CWD) in their rectal mucosa. In orally inoculated white-tailed deer, the presence of glycine (G) or serine (S) at codon 96 of the native PrP (denoted 96GG, 96GS or 96SS) appeared to influence the temporal patterns of PrP(CWD) deposition: nine out of 11 infected 96GG individuals had PrP(CWD) in their rectal mucosa by 342 days p.i., whereas only three out of seven infected 96GS individuals had PrP(CWD) in their rectal mucosa by 381 days p.i. and none of three 96SS individuals had PrP(CWD) in their rectal mucosa by 751 days p.i. These findings support further evaluation of rectal mucosa sampling in CWD surveillance.

• Test for detection of disease-associated prion aggregate in the blood of infected but asymptomatic animals.

  Authors: Binggong Chang, Xin Cheng, Shaoman Yin, Tao Pan, Hongtao Zhang, Poki Wong, Shin-Chung Kang, Fan Xiao, Huimin Yan, Chaoyang Li, Lisa L Wolfe, Michael W Miller, Thomas Wisniewski, Mark I Greene, Man-Sun Sy

  Clinical and vaccine immunology : CVI. 02/2007; 14(1):36-43.

  We have developed a sensitive in vitro assay for detecting disease-associated prion aggregates by combining an aggregation-specific enzyme-linked immunosorbent assay (AS-ELISA) with the fluorescentWe have developed a sensitive in vitro assay for detecting disease-associated prion aggregates by combining an aggregation-specific enzyme-linked immunosorbent assay (AS-ELISA) with the fluorescent amplification catalyzed by T7 RNA polymerase technique (FACTT). The new assay, named aggregation-specific FACTT (AS-FACTT), is much more sensitive than AS-ELISA and could detect prion aggregates in the brain of mice as early as 7 days after an intraperitoneal inoculation of PrP(Sc). However, AS-FACTT was still unable to detect prion aggregates in blood of infected mice. To further improve the detection limit of AS-FACTT, we added an additional prion amplification step (Am) and developed a third-generation assay, termed Am-A-FACTT. Am-A-FACTT has 100% sensitivity and specificity in detecting disease-associated prion aggregates in blood of infected mice at late but still asymptomatic stages of disease. At a very early stage, Am-A-FACTT had a sensitivity of 50% and a specificity of 100%. Most importantly, Am-A-FACTT also detects prion aggregates in blood of mule deer infected with the agent causing a naturally occurring prion disease, chronic wasting disease. Application of this assay to cattle, sheep, and humans could safeguard food supplies and prevent human contagion.

• Infectious prions in the saliva and blood of deer with chronic wasting disease.

  Authors: Candace K Mathiason, Jenny G Powers, Sallie J Dahmes, David A Osborn, Karl V Miller, Robert J Warren, Gary L Mason, Sheila A Hays, Jeanette Hayes-Klug, Davis M Seelig, Margaret A Wild, Lisa L Wolfe, Terry R Spraker, Michael W Miller, Christina J Sigurdson, Glenn C Telling, Edward A Hoover

  Science (New York, N.Y.). 11/2006; 314(5796):133-6.

  A critical concern in the transmission of prion diseases, including chronic wasting disease (CWD) of cervids, is the potential presence of prions in body fluids. To address this issue directly, weA critical concern in the transmission of prion diseases, including chronic wasting disease (CWD) of cervids, is the potential presence of prions in body fluids. To address this issue directly, we exposed cohorts of CWD-naïve deer to saliva, blood, or urine and feces from CWD-positive deer. We found infectious prions capable of transmitting CWD in saliva (by the oral route) and in blood (by transfusion). The results help to explain the facile transmission of CWD among cervids and prompt caution concerning contact with body fluids in prion infections.

• Suspected secondary thiafentanil intoxication in a captive mountain lion (Puma concolor).

  Authors: Lisa L Wolfe, Michael W Miller

  Journal of wildlife diseases. 11/2005; 41(4):829-33.

  Inadvertent ingestion of thiafentanil oxalate by a captive adult female mountain lion (Puma concolor) caused a prolonged clinical syndrome that included sedation and depression, muscle tension, andInadvertent ingestion of thiafentanil oxalate by a captive adult female mountain lion (Puma concolor) caused a prolonged clinical syndrome that included sedation and depression, muscle tension, and myopathy that was incompletely antagonized by naltrexone HCl. A serum chemistry profile revealed markedly elevated creatinine phosphokinase (CK; 490,450 IU/l), alanine aminotransferase (ALT; 1,896 IU/l), and aspartate aminotransferase (AST; 4,321 IU/l) 2 days after onset. The affected animal's condition gradually improved over the next 15 days in response to supportive therapy that included diazepam (5 mg as needed), Normasol R (3 l/day), dexamethasone (tapering dose starting at 1 mg/kg), and ketoprofen (1 mg/kg). She eventually recovered completely. Based on these observations, carcasses of animals immobilized with thiafentanil should be marked and disposed of properly to preclude opportunities for secondary exposure and potential intoxication in scavenging species. In addition, caution is advised when using thiafentanil in animals that could be preyed upon before full metabolism of the drug.

• Low frequency of PrP genotype 225SF among free-ranging mule deer (Odocoileus hemionus) with chronic wasting disease.

  Authors: Jean E Jewell, Mary M Conner, Lisa L Wolfe, Michael W Miller, Elizabeth S Williams

  The Journal of general virology. 08/2005; 86(Pt 8):2127-34.

  The prion protein (PrP) gene was characterized in 1482 free-ranging mule deer (Odocoileus hemionus) from Wyoming and Colorado. Using DNA sequences from 363 deer, dimorphisms at codons 20The prion protein (PrP) gene was characterized in 1482 free-ranging mule deer (Odocoileus hemionus) from Wyoming and Colorado. Using DNA sequences from 363 deer, dimorphisms at codons 20 (aspartate/glycine) and 225 [serine (S)/phenylalanine (F)] were found; silent changes occurred at codons 131 (tyrosine) and 247 (isoleucine). The remaining samples were surveyed for codon 225 genotype and all were characterized for chronic wasting disease (CWD) infection status. A total of 112 deer with the genotype 225SF or FF were found, of which one was CWD-positive; 1370 were 225SS, with 289 positive for CWD. Among CWD-negative deer, the frequency of 225SF/FF genotypes was 9.3 % but among CWD-positive deer it was only 0.3 %. For all samples combined, CWD status was not independent of codon 225 genotype (P<0.0001). The odds that a deer of the 225SS genotype was CWD-infected were 30 times greater (95 % confidence intervals=4-213) than for a 225SF deer. The proportion of 225SF animals in sampled subpopulations varied from 0 to 18 %; the CWD prevalence varied from 0 to 25 %. However, no relationship was observed between genotype frequency and CWD prevalence in different areas. The PrP sequences of experimentally infected mule deer were analysed from pre-existing projects and 10 animals were found with 225SF genotypes, all of which were positive for CWD. Data available from some of these animals suggest that the 225SF genotype could be associated with longer incubation periods in CWD infection compared with the 225SS genotype.