RT-QuIC amplification of CWD prions in winter ticks (Dermacentor albipictus) collected from North American elk (Cervus canadensis) in a CWD-endemic area

Chronic wasting disease (CWD) is a progressive and fatal spongiform encephalopathy of deer and elk species, caused by a misfolded variant of the normal prion protein. Horizontal transmission of the misfolded CWD prion between animals is thought to occur through shedding in saliva and other forms of excreta. The role of blood in CWD transmission is less clear, though infectivity has been demonstrated in various blood fractions. Blood-feeding insects, including ticks, are known vectors for a range of bacterial and viral infections in animals and humans, though to date there has been no evidence for their involvement in prion disease transmission. In the present study, we evaluated winter ticks (Dermacentor albipictus) collected from 136 North American elk (Cervus canadensis) in a CWD-endemic area for evidence of CWD prion amplification using the real time quaking-induced conversion assay (RT-QuIC). Although 30 elk were found to be CWD-positive (22%) postmortem, amplifiable prions were found in just a single tick collected from an elk in advanced stages of CWD infection, with some evidence for prions in ticks collected from elk in mid-stage infection. These findings suggest that further investigation of ticks as reservoirs for prion disease may be warranted.

Download Full-text

Evaluation of Winter Ticks (Dermacentor albipictus) Collected from North American Elk (Cervus canadensis) in an Area of Chronic Wasting Disease Endemicity for Evidence of PrP CWD Amplification Using Real-Time Quaking-Induced Conversion Assay

mSphere ◽

10.1128/msphere.00515-21 ◽

2021 ◽

Author(s):

N. J. Haley ◽

D. M. Henderson ◽

K. Senior ◽

M. Miller ◽

R. Donner

Keyword(s):

Real Time ◽

North American ◽

Chronic Wasting Disease ◽

Wasting Disease ◽

The Real ◽

First Finding ◽

North American Elk ◽

Dermacentor Albipictus ◽

Cervus Canadensis

This study reports the first finding of detectable levels of prions linked to chronic wasting disease in a tick collected from a clinically infected elk. Using the real-time quaking-induced conversion assay (RT-QuIC), “suspect” samples were also identified; these suspect ticks were more likely to have been collected from CWD-positive elk, though suspect amplification was also observed in ticks collected from CWD-negative elk.

Download Full-text

Human prion diseases: surgical lessons learned from iatrogenic prion transmission

Neurosurgical FOCUS ◽

10.3171/2016.5.focus15126 ◽

2016 ◽

Vol 41 (1) ◽

pp. E10 ◽

Cited By ~ 48

Author(s):

David J. Bonda ◽

Sunil Manjila ◽

Prachi Mehndiratta ◽

Fahd Khan ◽

Benjamin R. Miller ◽

...

Keyword(s):

Prion Disease ◽

Disease Transmission ◽

Prion Diseases ◽

The United States ◽

Lessons Learned ◽

World Health ◽

Transmissible Spongiform Encephalopathies ◽

Spongiform Encephalopathy ◽

Prion Transmission ◽

Iatrogenic Transmission

The human prion diseases, or transmissible spongiform encephalopathies, have captivated our imaginations since their discovery in the Fore linguistic group in Papua New Guinea in the 1950s. The mysterious and poorly understood “infectious protein” has become somewhat of a household name in many regions across the globe. From bovine spongiform encephalopathy (BSE), commonly identified as mad cow disease, to endocannibalism, media outlets have capitalized on these devastatingly fatal neurological conditions. Interestingly, since their discovery, there have been more than 492 incidents of iatrogenic transmission of prion diseases, largely resulting from prion-contaminated growth hormone and dura mater grafts. Although fewer than 9 cases of probable iatrogenic neurosurgical cases of Creutzfeldt-Jakob disease (CJD) have been reported worldwide, the likelihood of some missed cases and the potential for prion transmission by neurosurgery create considerable concern. Laboratory studies indicate that standard decontamination and sterilization procedures may be insufficient to completely remove infectivity from prion-contaminated instruments. In this unfortunate event, the instruments may transmit the prion disease to others. Much caution therefore should be taken in the absence of strong evidence against the presence of a prion disease in a neurosurgical patient. While the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have devised risk assessment and decontamination protocols for the prevention of iatrogenic transmission of the prion diseases, incidents of possible exposure to prions have unfortunately occurred in the United States. In this article, the authors outline the historical discoveries that led from kuru to the identification and isolation of the pathological prion proteins in addition to providing a brief description of human prion diseases and iatrogenic forms of CJD, a brief history of prion disease nosocomial transmission, and a summary of the CDC and WHO guidelines for prevention of prion disease transmission and decontamination of prion-contaminated neurosurgical instruments.

Download Full-text

Dehydration of Prions on Environmentally Relevant Surfaces Protects Them from Inactivation by Freezing and Thawing

Journal of Virology ◽

10.1128/jvi.02191-17 ◽

2018 ◽

Vol 92 (8) ◽

Cited By ~ 4

Author(s):

Qi Yuan ◽

Glenn Telling ◽

Shannon L. Bartelt-Hunt ◽

Jason C. Bartz

Keyword(s):

Prion Disease ◽

Disease Transmission ◽

Protein Misfolding ◽

Chronic Wasting Disease ◽

Control Strategies ◽

Horizontal Transmission ◽

Freezing And Thawing ◽

Wasting Disease ◽

Live Animal ◽

Weathering Processes

ABSTRACTChronic wasting disease (CWD) is an emerging prion disease in North America. Recent identification of CWD in wild cervids from Norway raises the concern of the spread of CWD in Europe. CWD infectivity can enter the environment through live animal excreta and carcasses where it can bind to soil. Well-characterized hamster prion strains and CWD field isolates in unadsorbed or soil-adsorbed forms that were either hydrated or dehydrated were subjected to repeated rounds of freezing and thawing. We found that 500 cycles of repeated freezing and thawing of hydrated samples significantly decreased the abundance of PrPScand reduced protein misfolding cyclic amplification (PMCA) seeding activity that could be rescued by binding to soil. Importantly, dehydration prior to freezing and thawing treatment largely protected PrPScfrom degradation, and the samples maintained PMCA seeding activity. We hypothesize that redistribution of water molecules during the freezing and thawing process alters the stability of PrPScaggregates. Overall, these results have significant implications for the assessment of prion persistence in the environment.IMPORTANCEPrions excreted into the environment by infected animals, such as elk and deer infected with chronic wasting disease, persist for years and thus facilitate horizontal transmission of the disease. Understanding the fate of prions in the environment is essential to control prion disease transmission. The significance of our study is that it provides information on the possibility of prion degradation and inactivation under natural weathering processes. This information is significant for remediation of prion-contaminated environments and development of prion disease control strategies.

Download Full-text

Physiologic Effects of Nasal Oxygen or Medical Air Administered Prior to and During Carfentanil– Xylazine Anesthesia in North American Elk (Cervus canadensis manitobensis)

Journal of Zoo and Wildlife Medicine ◽

10.1638/2007-0107.1 ◽

2009 ◽

Vol 40 (1) ◽

pp. 39-50 ◽

Cited By ~ 22

Author(s):

Jessica M. Paterson ◽

Nigel A. Caulkett ◽

Murray R. Woodbury

Keyword(s):

North American ◽

North American Elk ◽

Cervus Canadensis ◽

Medical Air

Download Full-text

Detection and Control of Prion Diseases in Food Animals

ISRN Veterinary Science ◽

10.5402/2012/254739 ◽

2012 ◽

Vol 2012 ◽

pp. 1-24 ◽

Cited By ~ 7

Author(s):

Peter Hedlin ◽

Ryan Taschuk ◽

Andrew Potter ◽

Philip Griebel ◽

Scott Napper

Keyword(s):

Prion Disease ◽

Disease Transmission ◽

Management Practices ◽

Prion Diseases ◽

Transmissible Spongiform Encephalopathies ◽

Spongiform Encephalopathy ◽

Case Scenario ◽

Worst Case ◽

Spongiform Encephalopathies ◽

Food Animals

Transmissible spongiform encephalopathies (TSEs), or prion diseases, represent a unique form of infectious disease based on misfolding of a self-protein (PrPC) into a pathological, infectious conformation (PrPSc). Prion diseases of food animals gained notoriety during the bovine spongiform encephalopathy (BSE) outbreak of the 1980s. In particular, disease transmission to humans, to the generation of a fatal, untreatable disease, elevated the perspective on livestock prion diseases from food production to food safety. While the immediate threat posed by BSE has been successfully addressed through surveillance and improved management practices, another prion disease is rapidly spreading. Chronic wasting disease (CWD), a prion disease of cervids, has been confirmed in wild and captive populations with devastating impact on the farmed cervid industries. Furthermore, the unabated spread of this disease through wild populations threatens a natural resource that is a source of considerable economic benefit and national pride. In a worst-case scenario, CWD may represent a zoonotic threat either through direct transmission via consumption of infected cervids or through a secondary food animal, such as cattle. This has energized efforts to understand prion diseases as well as to develop tools for disease detection, prevention, and management. Progress in each of these areas is discussed.

Download Full-text

Presence of subclinical infection in gene-targeted human prion protein transgenic mice exposed to atypical bovine spongiform encephalopathy

Journal of General Virology ◽

10.1099/vir.0.052738-0 ◽

2013 ◽

Vol 94 (12) ◽

pp. 2819-2827 ◽

Cited By ~ 11

Author(s):

Rona Wilson ◽

Karen Dobie ◽

Nora Hunter ◽

Cristina Casalone ◽

Thierry Baron ◽

...

Keyword(s):

Human Health ◽

Bovine Spongiform Encephalopathy ◽

Prion Protein ◽

Disease Transmission ◽

Large Scale ◽

Single Agent ◽

Diagnostic Methods ◽

Transmissible Spongiform Encephalopathies ◽

Spongiform Encephalopathy ◽

Human Prion Protein

The transmission of bovine spongiform encephalopathy (BSE) to humans, leading to variant Creutzfeldt–Jakob disease has demonstrated that cattle transmissible spongiform encephalopathies (TSEs) can pose a risk to human health. Until recently, TSE disease in cattle was thought to be caused by a single agent strain, BSE, also known as classical BSE, or BSE-C. However, due to the initiation of a large-scale surveillance programme throughout Europe, two atypical BSE strains, bovine amyloidotic spongiform encephalopathy (BASE, also named BSE-L) and BSE-H have since been discovered. To model the risk to human health, we previously inoculated these two forms of atypical BSE (BASE and BSE-H) into gene-targeted transgenic (Tg) mice expressing the human prion protein (PrP) (HuTg) but were unable to detect any signs of TSE pathology in these mice. However, despite the absence of TSE pathology, upon subpassage of some BASE-challenged HuTg mice, a TSE was observed in recipient gene-targeted bovine PrP Tg (Bov6) mice but not in HuTg mice. Disease transmission from apparently healthy individuals indicates the presence of subclinical BASE infection in mice expressing human PrP that cannot be identified by current diagnostic methods. However, due to the lack of transmission to HuTg mice on subpassage, the efficiency of mouse-to-mouse transmission of BASE appears to be low when mice express human rather than bovine PrP.

Download Full-text

North American channel catfish, Ictalurus punctatus: a neglected but potentially invasive freshwater fish species?

Biological Invasions ◽

10.1007/s10530-021-02459-x ◽

2021 ◽

Vol 23 (5) ◽

pp. 1563-1576 ◽

Cited By ~ 1

Author(s):

Phillip J. Haubrock ◽

Gordon H. Copp ◽

Iva Johović ◽

Paride Balzani ◽

Alberto F. Inghilesi ◽

...

Keyword(s):

North America ◽

Ictalurus Punctatus ◽

Channel Catfish ◽

North American ◽

Disease Transmission ◽

Native Species ◽

Assessment Protocol ◽

South Italy ◽

Wide Range ◽

North And South

AbstractThe North American channel catfish Ictalurus punctatus has been introduced to several locations in Europe but has received little or no scientific study despite its invasive attributes, including prolific reproduction, tolerance to a wide range of conditions, opportunistic feeding, at least partial ‘predator release’, and some evidence of environmental impacts (e.g. disease transmission). To assess the species’ potential invasiveness and the likely risks to native species and ecosystems in Europe, available literature from both North America and Europe was reviewed and used to carry out risk screenings of the species for the risk assessment areas, North and South Italy, using the Aquatic Invasiveness Screening Kit (AS-ISK), which was followed by a more detailed evaluation (for both North America and Europe) of the species’ potential impacts using the Environmental Impact Classification of Alien Taxa (EICAT) assessment protocol. The AS-ISK score indicated that channel catfish is likely to pose a high risk of being invasive in both North and South Italy, with EICAT scores indicating “Major” impacts for both North America and Europe, at high and medium confidence levels, respectively. The present results emphasise the urgent need to carry out in-depth studies on introduced populations of this species to understand better its invasive potential so as to inform management decisions on the appropriate control or eradication measures for invaded water bodies.

Download Full-text

Reproductive senescence in free-ranging North American elk Cervus elaphus Cervidae

Mammalia ◽

10.1515/mammalia-2018-0076 ◽

2019 ◽

Vol 83 (6) ◽

pp. 593-600 ◽

Cited By ~ 1

Author(s):

Louis C. Bender ◽

Jessica R. Piasecke

Keyword(s):

Age Structure ◽

Cervus Elaphus ◽

North American ◽

Reproductive Senescence ◽

Female Age ◽

North American Elk ◽

Age Related ◽

Consistent Manner ◽

Multiple Species ◽

Free Ranging

Abstract Successful production of calves is necessary for growth of North American elk (Cervus elaphus Linnaeus 1758) populations, but few studies have evaluated age-related effects on both the conception and survival of a calf to weaning in multiple free-ranging populations. Conception and survival of calves to weaning were both affected by maternal age, with old (age 9 and older) females showing reproductive senescence as compared to prime-aged (ages 2–8) females despite achieving similar or greater size and condition. Reproductive senescence in our free-ranging populations ultimately resulted in old females weaning fewer calves (0.42 calves/female) than did prime-aged females (0.64 calves/female). Other factors, especially maternal size, also influenced conception and survival to weaning, and these interacted with age in a consistent manner, i.e. larger females or females in better condition were more likely to conceive and successfully wean calves within each age class. Female age structure receives less consideration in ungulate management than does male age structure, despite demonstrated impacts on population productivity of multiple species because of reproductive senescence. Because of the large proportion of individuals in senesced age classes in elk populations, low productivity in populations may simply reflect female age structure, rather than other frequently hypothesized factors.

Download Full-text