Duration: 10/01/2025 to 09/30/2030

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Chronic Wasting Disease (CWD) is a prion disease that affects deer, elk and moose. The disease is always fatal and, in some areas with high numbers of infected deer and/or elk, is resulting in population declines. CWD is now present in 35 states in the US and 4 provinces in Canada, and continues to spread. The numbers of infected animals also continues to increase with some populations having 80% of their bucks infected. There is no treatment, no cure, and an incomplete understanding of best management practices. As infected animals secrete infectious CWD, the environment also becomes contaminated for unknown lengths of time. It is the goal of this Consortium to provide expertise and knowledge pertaining to this disease and to use this knowledge to develop approaches for, at the minimum, slowing the aggressive growth and spread of the disease. The impacts of this work will affect a broad number of stakeholders (landowners, hunters, Indigenous communities, and the businesses associated with these groups). By combining the expertise of basic and applied researchers with wildlife managers, we will be able to provide the scientific basis for management of this insidious disease.

Statement of Issues and Justification

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE), or prion disease, of North American deer, elk and moose (cervids) (Williams 2005). Other TSEs include Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (“mad cow” disease) in cattle, and scrapie in sheep and goats. TSEs are inevitably fatal, progressive neurodegenerative diseases with long incubation periods and no known cure (Vallabh et al., 2020). Although CWD was initially isolated to the front range of the Rocky Mountains in the 1970s, since the early 2000s, CWD has expanded to include 35 U.S. states, four Canadian provinces, Scandinavia, and South Korea. The geographic range of the disease continues to grow, prevalence is increasing, and the disease has acquired new hosts (viz. moose and reindeer; Baeten et al. 2007, Benestad et al. 2016). In addition to affecting wild cervid populations, CWD in North America poses a potential risk to the agricultural industry, outdoor recreation, and human health. In states where CWD is established, it has emerged as a major threat to cervids in some areas, reducing the health of deer populations and causing long-term population decline (Edmunds et al. 2016, Gross and Miller 2001, Manjerovic et al. 2014). As CWD directly threatens free-ranging North American cervid populations, it can challenge the fiscal foundations of wildlife conservation in the U.S. Sales of deer hunting licenses constitute a large proportion of annual revenue supporting conservation and management programs across taxa. Declines in these revenues due to CWD threatens the financial cornerstone of state fisheries and wildlife programs. Transmission to humans has not been documented, but the Centers for Disease Control and Prevention advises hunters to not consume the meat of infected animals as CWD is a prion disease like bovine spongiform encephalopathy (BSE). BSE does infect humans, resulting in fatal human prion disease (CDC 2017). Uncertainties about human and livestock susceptibility, environmental contamination, and the ability of plants to accumulate the disease agent raise food and feed safety concerns (Hamir et al., 2011; Moore et al., 2017; Race et al 2009; 2018; Marsh et al., 2005; Pritzkow et al., 2015). Finally, emerging evidence is increasing concern that CWD may pose a risk to human health, and even perceptions that humans may become infected will have dramatic ecological and social consequences.

The infectious agent of CWD is a prion, an infectious, misfolded form (denoted as PrPCWD or PrPSc) of the normally benign prion protein (denoted as PrPC). Misfolded prion protein accumulates in the brainstem and lymphatic tissue of infected animals, and to a lesser extent in muscle and other tissues (Sigurdson et al. 2002, Angers et al. 2006, Henderson et al. 2015a, Spraker et al. 2015, Davenport et al. 2018, Otero et al. 2019). The disease propagates via a process in which infectious PrPCWD templates the conformational conversion of PrPC into PrPCWD (Lansbury & Caughey, 1995). This templating property of prions has been exploited to develop a variety of amplification assays that can be used to detect prions in tissues, secretions, excreta, and environmental samples (Haley et al. 2012, Henderson et al. 2015b, Pritzkow et al. 2015, Denkers et al. 2016, Henderson et al. 2017, Plummer et al. 2018 Ferreira & Caughey, 2020).

Chronic wasting disease is transmitted directly through animal-to-animal contact and indirectly through contact with contaminated environments (Miller et al. 2004). Infected deer shed prions through secretions and excreta (Miller et al. 2004, Mathiason et al. 2006, Safar et al. 2008, Haley et al. 2009, Tamgüney et al. 2009), and human-facilitated movement of infected live deer, animal parts and/or carcasses contributes to the geographic spread of CWD. Prion shedding from infected animals is not yet fully understood. CWD prions are shed throughout the incubation period of the disease but not necessarily in a consistent manner (Cheng et al, 2019; Denkers et al., 2024). Although there is some data on relative amounts of CWD prion infectivity in secretions/excreta (relative to infectivity in the brain), the link between detection of CWD prions in excreta/secreta and infection is poorly understood (i.e., is the titer of prions in saliva sufficient to cause infection in another cervid?). Also, transmission rate and mode for CWD have not been determined (Almberg et al. 2011, Smolko et al., 2021). Surveillance and epidemiological models specific to CWD and deer in highly productive habitats of the Midwest and Northeast suggest the disease is in early- to mid-stages of infection (Williams et al. 2014; Bondo et al., 2024; Evans et al., 2016; Hefley et al., 2017; Manjerovic et al., 2024). Initial studies suggest that CWD prions persist at various levels in the environment, at as yet undetermined titers, hindering our understanding of how and where environmental transmissions may occur (Plummer et al. 2018, Kuznetsova et al. 2024, Huang et al. 2024).

Prions shed into the environment remain infectious for years (Brown & Gajdusek. 1991, Miller et al. 2004, Georgsson et al. 2006, Seidel et al. 2007). These prions are remarkably resistant to most inactivation procedures that are effective against conventional infectious agents (e.g., many chemical disinfectants, autoclaving under conventional conductions, ionizing radiation, desiccation; Taylor 1999, Colby and Prusiner 2011). However, some treatments are effective, at least in laboratory settings (e.g., concentrated hypochlorous acid, sodium hydroxide, peroxymonosulfate, humic acid; Taylor 1999, Chesney et al. 2016, Williams et al. 2019, Giachin et al., 2014, Kuznetsova et al., 2018). No cure exists for CWD and non-management options (i.e., environmental decontamination and/or vaccines)  for disease mitigation have failed to show efficacy. Deer shed prions long before they manifest any outward signs of CWD (e.g., emaciation, disorientation, fearlessness, paralysis; Henderson et al. 2015). Therefore, reducing environmental contamination would benefit from detection and removal of diseased deer from the landscape well before clinical disease signs are exhibited.

Benefit of a Multistate Effort. Chronic wasting disease is distributed widely in North America, affects multiple cervid species, and does not respect jurisdictional boundaries. Research across multiple disciplines is needed to fully address the complexities of CWD and acquire the knowledge needed to limit or eliminate its growth and spread. A multistate CWD effort to coordinate research across jurisdictions would be beneficial for several reasons.

•   The ecology of CWD differs across the regions and jurisdictions in which it occurs due to variation in species, climate, surficial geology, habitat, and land use.


•   Host prion protein genotype (PRNP) distribution varies geographically. While no genotype is known to confer complete resistance to CWD, susceptibility to the disease depends on PRNP genotype (Johnson et al. 2006). Host PRNP genotype can affect management strategies.


•   Different strains of CWD exist and can be distinguished by the length of incubation period, as well as biological and biochemical properties. There is, to date, no rapid means of distinguishing many strains. Different CWD prion strains may occur in different geographic areas due to differences in cervid species that are present, and different allelic variations in PRNP. Prion shedding into the environment by infected individuals may differ in magnitude or in dynamics by CWD strain (or host genotype). Strains may differ in their zoonotic and cross-species potential and can affect management strategies.


•   A multistate effort facilitates the coordination of resources. Resources include funding for joint research efforts, sources of negative control animals or tissues, a clearinghouse for reference samples, large-scale research facilities, and increased capacity through a human resource network.


•   Jurisdictions impacted by CWD differ in their surveillance approaches. Standardization across jurisdictions would facilitate data sharing and increase epidemiological understanding of CWD dynamics.


•   Jurisdictions impacted by CWD differ in their legal authorities to minimize spread and resulting policy or management responses. Multi-state research provides the opportunity to assess the effectiveness of different regulatory strategies.


•   Disease management activities (or lack thereof) in one jurisdiction can affect the spread of the disease in another. Coordination across jurisdictional boundaries will improve the efficacy of disease surveillance and management and can enhance consistency and coordination between jurisdictions as well as accelerate learning about effective management strategies.

State and federal policies require public support and, frequently, funding for implementation. Given emerging research and perceptions around human health risk, as well as the growing footprint of CWD and CWD-related management, public health departments, natural resource agencies, and agricultural agencies are becoming increasingly involved with communication and public engagement regarding CWD. Understanding public attitudes, values, risk perceptions, and associated behavior will be critical for the development of socially accepted disease response strategies and effective strategies for addressing CWD. This multistate research project would continue our previous successes at facilitating sharing of knowledge, data and resources, promoting interdisciplinary collaboration among researchers and managers in different jurisdictions, and serving as a vehicle through which to communicate research and management priorities to national decision-makers. The multistate project will continue to foster information exchange among universities and researchers with common goals, but with different backgrounds and knowledge bases. Increased collaboration improves research quality and avoids duplication of work at a critical time when effective solutions are needed quickly. Although the current multistate project has improved collaborative efforts, research on and management of CWD across North America is still fragmented and minimally coordinated leading to issues of data comparability, duplication of effort, and concerns about the validity of measurements. This proposed multistate project continues to build on the successes of the previous 5 years and would continue to improve the quality of CWD research and management nationally.

Contributions of the Participating Agricultural Experiment Stations. Nearly half of the current project membership is associated with State Agricultural Experiment Stations. These 32 participants serve on the executive committee, serve as leads of the objectives, and actively participate in the collaborative publications, communications, and project meetings. These members come from the following 14 institutions:

University of Arkansas

Colorado State University

University of Georgia

Iowa State University

Michigan State University

University of Minnesota

Mississippi State University

University of Missouri

Cornell University

The Pennsylvania State University

South Dakota State University

University of Tennessee

Texas A&M University

University of Wisconsin

 

Related, Current and Previous Work

Over the past 5 years, the North American Interdisciplinary Chronic Wasting Disease Research Consortium (hence referred to as The Consortium), has made significant accomplishments despite its first years occurring during the pandemic. The Consortium had identified five focus areas of CWD biology and management that require concentrated effort to provide science-based solutions to managing CWD. These are: i) a national CWD tissue and reagents repository, ii) large-scale research facilities for controlled CWD research, iii) CWD diagnostics, iv) evaluating management strategies across state boundaries and v) using social science to inform CWD management. Based on input at the 2023 annual meeting and approval by the membership, an additional two objectives were added; these are: i)  the characterization of CWD strains and their potential role in CWD spillover (objective #6) and  ii) contamination of the environment with CWD prions (objective #7). 

In the previous five years of the CWD multistate project, members have have contributed to the following activities to advance CWD research across North America:

• 26+ invited presentations, webinars, and podcasts to communicate the latest CWD science to the general public,


• 15+ collaborative CWD research grants received,


• 36+ collaborative scientific manuscripts, including a direct multistate project product: Bartz et al. 2024 - Chronic Wasting Disease: State of the Science Pathogens 2024, 13, 138.

Details of these contributions and additional information on activities of the CWD multistate project can be found at https://www.cwd-research.com/

 

Objective #1:  Disease Transmission and Pathogenesis–CWD Tissue Bioarchives

When normal cellular prion protein (PrPC) misfolds to an abnormal conformation (PrPCWD) it causes CWD infections. Different conformations of PrPsc result in various disease phenotypes with regard to pathogenicity, incubation time, and host range. These different phenotypes characterize different prion strains. The types of CWD strains are crucial to tracking distributions and progression of CWD, which has been a challenge in North America. One approach to overcome this obstacle by introducing a national repository for CWD which would have multiple benefits. First, with tissues collected on a large geographic scale in North America, we can assess the distribution, frequency, and strain types to their point of origin. Second, we can learn interactions among host ranges, strains, and environments along with collecting metadata. Third, the repository can provide standardized CWD-infected and uninfected tissue resources to develop diagnostic and testing methods for multiple research purposes. Finally, implementations of the repository will serve as a centralized platform to facilitate cooperation and resource-sharing between state agencies and research institutes.

The Strain and Genetic Online Tissue Repository (SAGOTR) was developed as a direct result of this objective and will serve two roles. First, a public view where all data associated with a tissue sample in SAGOTR can be viewed and searched by the public, but only species, CWD status and tissue holder’s contact information is available to the user. Second, a user interface (provider view) is designed to allow a user to search for tissue samples of interest and download their contact information. The database can be searched by map function or by advanced text search. For contributors, in the provider view, all metadata in SAGOTR are stored as data contributor-created projects. This was designed to be a collaborative network for the CWD research community that allows more effective and efficient sharing of CWD-positive tissues through SAGOTR – a united digital infrastructure.  

Objective #2: Research facilities for controlled CWD transmission experiments

Over the past 40 years, the basic biology of CWD has been discovered by way of experiments performed using cervids. Discoveries have included i) that CWD is a prion disease (Williams & Young, 1980), ii) that disease is transmitted via indirect and direct routes [Miller et al., 2004), iii) the identification of disease-modifying alleles (Johnson et al., 2011,Miller et al., 2012),) iv) the isolation of CWD strains (Johnson et al., 2011, Duque Velasquez et al., 2020), v) estimated the minimal oral lethal dose (Denkers et al., 2020), vi) quantified prion shedding in feces (Tamguney et al., 2009,Tennant et al., 2020), saliva and urine (Haley et al., 2011) and vii) established vertical transmission (Nalls et al., 2013). These basic data on the pathophysiology and transmission of CWD in the natural host is not available through other non-cervid research models.

While these experiments, conducted with cervids, have laid the foundation for current disease management approaches, much work remains towards the identification of mechanisms of the transmission of CWD. Primary findings are almost never repeated and basic disease parameter estimates (incubation period, oral L.D.50, pathogen deposition) have been derived by observation of low numbers of animals. In some instances, the entire understanding of certain disease aspects is derived from one or two deer.

Hypotheses about transmission, pathology, strains, genetics, prion shedding, and diagnostics or vaccines can only be tested in cervids with longitudinal infection studies under controlled conditions where the CWD strain and exposure time, route and dose are known. Resources for CWD transmission studies include high biocontainment animal laboratories, captive cervid facilities where disease is endemic, depopulated captive cervid facilities, and wild landscapes where CWD is endemic. Each of these types of facilities offers different capabilities for testing varying hypotheses on the transmission of CWD, the deposition and shedding of CWD prions and determining the basic disease biology. For example, it would be dangerous to perform experiments that induce the evolution of CWD prions outside of high biocontainment. Similarly, a test of a transmission mechanism in high containment does not mean that the same process is driving transmission on the landscape or in captive herds.

Objective #3: Improving Diagnostic Testing for CWD

While CWD continues to spread across the United States and globally, approved diagnostic options remain limited, and largely require postmortem sampling. Newer technologies that amplify prions in a sample such as real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA) offer the ability to detect prions in lower concentrations from antemortem or environmental samples. One of the major outcomes from this objective was a collaborative effort between the USDA Agricultural Research Service, the United States Geological Survey, University of Wisconsin Madison, the National institute of Health Rocky Mountain Laboratory, and USDA Veterinary Services, to develop and validate a standardized RT-QuIC protocol for use on postmortem medial retropharyngeal lymph nodes (MRPLN), and antemortem rectal and tonsil biopsies. In addition, a standardized substrate was developed by the University of Minnesota for the assay. This standardized protocol was tested by six National Animal Health Laboratory Network (NAHLN) diagnostic laboratories (MO, WI, Cornell, PA, MN, MI) that received funding from 2021 USDA APHIS CWD Cooperative Agreements in a blinded manner on characterized white-tailed deer samples to establish the RT-QuIC sensitivity and specificity for these sample types. This data was then reviewed by the USDA Veterinary Services Cervid Health Program and the National Veterinary Services Laboratory. Although the test shows promise, the results were too variable for the USDA to use in the current CWD program across multiple NAHLN laboratories (Darish et al., 2024). APHIS is working closely with several partners to evaluate ways to improve the reliability of the assay. Additionally, the Caughey group at the National Institute of Health-Rocky Mountain Laboratory has completed preliminary research in which an easily accessed diagnostic specimen, ear pinna punches and an improved RT-QuIC assay involving iron oxide magnetic extraction (IOME), was used to detect CWD infections in mule deer and white-tailed deer (Ferreira et al., 2021). Comparison of multiple areas of the ear pinna indicated that a central punch spanning the auricular nerve provided the most consistent detection of CWD infection. When compared to results obtained from gold-standard MRPLN specimens, RT-QuIC analyses of ear samples provided apparent diagnostic sensitivity (81%) and specificity (91%) that rivaled, or improved upon, those observed in previous analyses of rectal biopsies using RT-QuIC. These results provide evidence that RT-QuIC analysis of ear pinna punches may be a useful approach to detecting CWD infections in live cervids. This research has resulted in several additional research projects and publications investigating the use of ear pinna punches for CWD diagnostics.

RT-QuIC testing of blinded MRPLN samples was completed and followed with a transgenic mouse bioassay to more clearly establish specificity by differentiating the rate of true false positives compared to the rate at which RT-QuIC may detect CWD at an earlier time point than immunohistochemistry.  Mouse bioassays require months to years to complete, so this work is ongoing. 

In addition, many members of the consortium have offered up shared substrates, training, samples, and virtual discussions to facilitate onboarding of RT-QuIC or PMCA for other members to enable them to onboard the assays in their laboratories and to assist with other cross lab validations.

Objective #4: Evaluating Management Strategies across State Boundaries

This objective is focused on developing a multi-jurisdictional adaptive management project aimed at evaluating novel approaches for improving chronic wasting disease (CWD) and more broadly white-tailed deer management across the Midwest. This is a multi-year effort initiated by the CWD Research Consortium and led by MAFWA states.  The impetus for this objective stems from the fact that CWD and deer population management are significant challenges faced by Midwestern wildlife management agencies. Both deer populations and CWD continue to increase and current approaches to deer management do not appear to be efficacious, and those that have shown the most promise, such as sharpshooting, are likely unsustainable due to rising costs and shifting public perceptions. Thus, there is a desperate need to evaluate novel management approaches while working regionally to permit the cost and impacts of this effort to be distributed across jurisdictions and promote consistent messaging.

To meet this need, Consortium members and CWD researchers and managers, from wildlife agencies from IL, IN, IA, MI, MN, MO, OH, WI, have been working to design this multi-jurisdictional adaptive management project. We have made significant progress in this regard. This group has met regularly over the course of the current NIMSS project, and in August 2023, the group met in person in East Lansing, MI. Subsequent to the in-person meeting, we have met bi-weekly to refine the project design. We have used a structured decision-making (SDM) process to guide project development. The management action that was selected through our SDM process consists of three modules. Foremost is the ecological module, which centers on deer population management actions and its impacts on CWD. The second module focuses on the epidemiology of CWD, specifically targeting the reduction of CWD prion availability on the landscape. Lastly, the sociological module targets agency actions and outreach and human dimension efforts aimed at enhancing participation and engagement among stakeholder groups in deer population and CWD management. Current efforts are now focused on design and implementation of our selected management action.

 

Objective #5:Social Science and Management

The success of CWD science and management is inextricably linked to human behavior.Therefore, understanding of social values, motivations, attitudes, and how to influence behaviors is critical to promoting actions supportive of research and management efforts. Currently, knowledge on these topics is inadequate to evaluate and inform disease management decision-making at multiple jurisdictional levels, and insufficient to develop effective, targeted, and consistent outreach and communication strategies needed to gain and maintain public support for necessary management interventions. Research in human dimensions of CWD management, including the link between social science approaches and acceptance of and participation in disease management responses, is needed to effectively design and implement management strategies. Additionally, stakeholder attitudes towards management interventions are varied and expected to evolve with CWD epizootics such that regions with no prior experience with the disease may differ from regions with a long history of the disease. A specific effort related to our work on human dimensions is a multi-state project led by the Center for Conservation Social Sciences of Cornell University (Bruce Lauber, PI), it encompasses multiple Consortium participants. Consortium members have also developed research initiated from this project objective on quantifying intention versus realized behavior and how to better guide hunter behavior, and landowner willingness to allow land access for CWD management. These actionable and human dimensions studies will improve our ability to effectively mitigate CWD.

Objective #6: Strain Characterization

As noted above, there have been multiple CWD strains described in North American cervids; these differ from Scandinavian CWD strains. At least 10 strains of CWD have been described (Angers et al., 2010,  Duque Velasquez et al., 2015,Wolfe & Miller, 2014, O’Rourke et al., 2007, ; Hannaoui et al., 2021, Baeten et al., 2007, Pirisinu et al., 2018,  Benestad et al., 2016,  Vikoren et al., 2018]. Strains are operationally defined  based on biological and biochemical features (primary structure, protease resistance, conformational stability, neuropathology, incubation period, host range), often following transmission into laboratory rodents. These techniques, although robust, are time-consuming (due to relatively long incubation periods) and correspondingly expensive. 

The lack of knowledge about CWD strains (their distribution, their impact on disease transmission, link to PRNP genetics etc) is a significant knowledge gap. Furthermore, this lack of knowledge then precludes disease management and assessment of zoonotic risk. Rapid identification of CWD prion strains would provide the potential to link specific CWD outbreaks and thus, identify mechanisms of transmission.  Rapid identification of strains would  provide a means of understanding the potential for spillover into humans and other species. Consider, by contrast, the usefulness of strain identification and tracing in other infectious diseases such as avian influenza, tuberculosis or Covid-19. With CWD, strain identification is not being performed despite the knowledge that prion strains exist and fundamentally alter disease.

No human cases of CWD infection have been reported suggesting  a substantial barrier between the prevalent CWD strains and humans, but it does not necessarily mean that CWD spillover into humans has not happened. In vitro assays (PMCA and RT-QuIC) show that human PrPC  can be converted by CWD prions. There is also limited in vivo evidence for low zoonotic risks from animal model studies. Whether CWD can infect humans at low levels in the real world is still an open question.  In vitro assays suggest that CWD can become zoonotic after adaptation to raccoons, suggesting possible CWD zoonosis through an intermediary species (Moore et al., 2022; Cassmann et al., 2022, Barrio et al., 2024) .

Human exposure to CWD is very significant. Based on a 2017 estimate, 7,000-15,000 CWD-affected deer/elk were consumed annually, corresponding to 21,000-60,000 people exposed annually. Recent estimates are much higher, and the numbers are expected to increase over time. Exposure of CWD to humans is high due to the following factors: 

1. Widespread and continuing geographic expansion of CWDacross North America.


2. Increased prevalence of CWD in cervid species with time.


3. High dose exposure of affected hunters and their families because the harvested animal is usually primarily consumed within the hunter’s family.


4. Significant prion infectivity in tissues people consume (muscles and antler velvet) and bodily fluids (blood, saliva) and tissue debris (brain and other tissues) that people are exposed to during handling and dressing of carcasses. Nasal inhalation and dermal exposure through cuts and wounds, shown to be highly efficient routes for prion infection, are possible during handling and dressing of carcasses.


5. Animal processing is often done by processing shops, which often distribute the meat by weight, not by the source animal, and the equipment and surfaces are likely contaminated by CWD. This common practice results in cross contamination and increased hard-to-track human exposure to CWD. 


6. Contamination of the environment (soil, plants and other fomites). These CWD prions persist for at least 2 years, perhaps longer.

The CWD zoonotic risk is also compounded by the existence of multiple strains of CWD: these strains may have differential capacity to infect other hosts (including humans).

Objective #7. Environmental

Chronic wasting disease is somewhat distinctive amongst prion diseases in that it is highly likely that interactions in the broader environment likely figure heavily in almost all aspects of the disease. The highly recalcitrant nature of prion protein aggregates combined with the existence of CWD in free-ranging species means that environmental contamination and transmission are possible drivers of disease spread. However, the question of the extent to which environmental factors contribute to CWD ecology is largely unanswered. 

The Consortium holds amongst its membership the most experienced and impactful researchers in the field of environmental prion research. During the first phase of the North American interdisciplinary chronic wasting disease research consortium, there was no specific objective associated with bioavailability of prions in the environment, though several aspects were somewhat encompassed in others (Objectives 1, 2, and 3 specifically). Eventually, it became apparent that the breadth and importance of the environmental question necessitated its own objective within the consortium.

The environmental aspects of CWD can be thought of as several interconnected spheres of study. From an animal perspective, an accurate quantification of the total prion load generated by and released into the environment has not yet been determined. Some earlier works have estimated this, with some degree of success (Henderson et al., 2015a), though variability in disease progression, animal survival, and behavior all all contribute to the prion load introduced into the environment. Soil, the upper layers of the lithosphere which provide a matrix for plant growth, is the first media which will be subject to CWD prion contamination. In spite of multiple studies confirming the extremely long persistence of prions in the soil (Brown & Gajdusek, 1991, Georgsson et al., 2006, Somerville et al., 2019), no maximum duration of persistence has been identified. Likewise, though highly probable, no definitive connection between environmental CWD prion exposure and transmission has been established in wild populations. A confounding factor is the extreme (functionally infinite) heterogeneity in soil physical and chemical composition, which influences nearly all aspects of soil-prion interactions (Johnson et al., 2007, Holec et al., 2019, Kuznetsova et al., 2020). Building upon this concept, there are multiple possible routes of infection from the broader environment. Plant uptake of prions and subsequent infectivity has been identified in laboratory studies (Pritzkow et al., 2015, Carlson et al., 2023), but the true implications of plant-prion interactions are severely understudied. As with the soil question, the extreme heterogeneities between different plant species’ physiology and biochemistry leads to complexity that is unlikely to be answered by individual research groups. Thus, the scope of the environmental CWD question requires coordinated effort between multiple agencies, laboratories, and stakeholders.   

Objectives

1. Disease Transmission and Pathogenesis–CWD Tissue Bioarchives.
   Comments: The overall goal of this objective is to establish a national CWD tissue and reagents repository to facilitate assessment of CWD strains to provide uniform standardized samples for development of diagnostics as well as basic research.
2. Research facilities for controlled CWD transmission experiments
   Comments: As much of CWD pathogenesis/transmission has been described using models of CWD and/or has been performed within laboratories, there is an ongoing need for facilities for both controlled challenge experiments and exploration of environmental transmission under controlled settings.
3. Improving Diagnostic Testing for CWD.
   Comments: To enhance control and disease management of CWD in cervids, it is critical to improve/validate diagnostic testing with an emphasis on standardization, ante-mortem, and environmental testing
4. Evaluating Management Strategies across State Boundaries.
   Comments: To improve CWD management strategies, enhancing our ability to adaptively manage CWD is essential and employing a multi-state effort, aimed at evaluating novel approaches to reduce transmission through host population management, is an effective approach to rapidly increasing understanding of the efficacy of CWD management tools.
5. Enhancing coordination, understanding, and communication of social science as it relates to CWD research and management.
   Comments: Effective management of CWD must involve key stakeholders and, thus, delineating the impacts of human dimensions on CWD management will help assess management strategy effectiveness.
6. Characterization of CWD strains
   Comments: To conduct systematic delineation of the different naturally occurring CWD strains and their properties (both biochemical and biological) which will underpin management as well as provide information regarding the potential for CWD spillover to non-cervid species, including humans.
7. Environmental contamination by infectious prions
   Comments: Environmental persistence of CWD prions depends on environmental conditions enhancing the need for collaborative approaches across the varied geographies of North America to further our understanding of environmental variation on CWD transmission dynamics and underpin development of CWD containment strategies.

Methods

Objective #1:  Disease Transmission and Pathogenesis–CWD Tissue Bioarchives

Cloud-based infrastructure

SAGOTR will be deployed using cloud-based infrastructure in a way that will be sustainable and can be easily maintained by a representative organization for future generations. Schema-Data about each sample will include, at least but may not be limited to: collection location, species, sex, age, tissue type (e.g. retropharyngeal lymph node, obex), prion protein genotype, physical location of stored sample, and contact information of organization housing the sample. Initial work has already been done to understand data needs and define a schema. The outcomes of this will be provided and should serve as a starting point for this aspect of the system. The schema should also include Provider level data, including Provider contact information, citation requirements, and other data as described in the previously developed schema. API and Bulk Upload-Many Providers collect and manage very large numbers (hundreds) of samples. Sample data are stored in spreadsheets or databases. SAGOTR must allow organizations to integrate their own tissue management systems and processes within SAGOTR. To lower the barriers to participation, easy data entry and upload solutions must be made available. An API is critical for data pipelining from existing Provider databases and for other data management functions. A bulk data upload option must also be available. The bulk data upload process should be limited in scope to follow strict rules. Only CSV files will be accepted and allowed values will be defined in advance. Errors should result in the rejection of the entire upload. 

Data Access Control-Providers must have the ability to manage their own users. Provider user roles will include, at a minimum, a provider administrator, provider data manager, and provider user. Provider administrators will have full privileges to manage users and Provider level settings. Provider data managers will be allowed to create, edit, and delete sample data. And Provider users will have permission to view all Provider sample data. System Administrators will have permissions that allow them to set up Providers and create Provider Administrators and assist if needed. The base level public view must be able to explore and query tissue sample data and contact a Provider to request samples. Due to the potential sensitivity of some data, it will be necessary to prevent access to portions of the sample data by field at a Provider or sample level. System users may self-register using valid email addresses and will be assigned the User role by default. 

A user interface and associated workflows for researchers-For use throughout the research community, SAGOTR should be accessible to external researchers interested in acquiring samples. External researchers will explore and search for desired tissue samples using a map and/or table interface. The researcher may contact the Provider through the system. One or more forms may be needed to manage communication and the template is yet to be determined. 

A user interface and associated workflow for Providers-Providers will require a custom user interface and associated processes/workflows for: creating, updating, and deleting tissue sample data manually or through bulk upload (CSV with a provided template), querying (listing/filtering/exporting) tissue sample data, and visualizing/summarizing tissue sample data (simple summary statistics/maps).

Integration with complementary infrastructure-It is expected that most samples added to SAGOTR will be contributed by state and provincial wildlife agencies that are Providers in the CWD Data Warehouse. Therefore, integration and communication of data between the two systems will provide significant benefit. The degree to which the virtual CWD tissue repository and CWD Data Warehouse are integrated should be explored during subsequent phases of this effort. Biological Archive System-Subsequent to initiation of efforts to develop SAGOTR, United State Department of Agriculture/Animal and Plant Health Inspection Services initiated development of a physical repository for storage of tissue samples for archiving at the National Wildlife Research Center in Fort Collins, Colorado. This system will have permanent freezers, support staff, and Freezerworks program to manage inventory housed in the physical repository.

Objective #2: Research facilities for controlled CWD transmission experiments

Progress on all aspects of CWD is complicated by the limited national capacity and capability for mechanistic and longitudinal studies in cervids. The consortium has inventoried facilities where CWD research is being performed to understand existing capabilities and capacity and identify new opportunities for collaboration. Current capacity is estimated at 100 cervids/year. As the incubation period of CWD can exceed three years, only a limited number of experiments can be conducted at one time. Capabilities are limited by facility designs. Experiments with mule-deer, elk and moose are especially restricted. Sources of CWD negative cervid research models are also limited as the geographical distribution of CWD increases. Barriers to establishing new resources are high and include the expense of housing large animals for long periods of time and the need for specialized decontamination protocols. The vast majority of controlled CWD transmission experiments currently occur at only 2 laboratories. 

Directly developing or operating facilities for CWD research is beyond the scope of the consortium. Our approach is to leverage consortium members' professional and institutional connections to meet identified research needs, extend capacity and develop new capabilities. The goal is to establish collaborations that fill research gaps and advance CWD science while sharing and allocating scarce resources. Where identified gaps cannot be met, the consortium is well designed to construct scientific justification to address those gaps by engaging with stakeholders and explaining the disease management benefits to be obtained by committing resources. 

Objective #3: Improving Diagnostic Testing for CWD

Validating RT-QuIC for diagnostics on gold standard samples - A second ring trial for MRPLNs will be completed. For this trial, samples will be tested using two commercially available substrates (Priogen and VMRD), with well characterized controls, and an agreement on protocols and data analysis prior to testing by the labs. We are working towards obtaining reproducibility with respect to high sensitivity and specificity between labs and moving the needle for RT-QuIC as a postmortem diagnostic test on MRPLNs. The plan is for the samples from well characterized animals (e.g., age, sex, genetics, location ,etc.) to have results for both ELISA and IHC at a minimum, with the goal of using samples that have also been tested by PMCA and bioassay, if possible, to show a full comparison of different testing methods and have the samples as well characterized as possible.  

Optimizing amplification assays for antemortem and environmental sample types - While this group is not as far progressed with cross-laboratory evaluation for antemortem and postmortem sample types, similar procedures as described above will be conducted initially between smaller sets of lab groups. These data as completed will be disseminated back to the larger objective group to plan next best sample types to validate on a larger scale. These sample types will include those that can be taken from a live animal, the environment, and animals or insects that may act as vectors. 

Quantification of prions based on amplification assay results - In a significant step towards moving both RT-QuIC and PMCA from a more qualitative (yes/no detection) assay to a quantification assay, a recent paper from Dr. Caughey’s group has identified experimental conditions and post hoc mathematical analysis allowing for quantification using RT-QuIC (Srivastiva et al., 2024). This objective will plan to expand the use of these analyses.   

Defining common terminology and procedures for amplification assays - We would like to have consensus and provide case definitions and standardization of the terminology associated with CWD diagnostics and RT-QuIC and PMCA. This would include which assays are most useful for a specific sample type and how diagnostics are determined (procedures for testing and verification of results.)     

Determining how CWD stain type affects amplification assay performance - There is the need to clarify how strain types of CWD are defined by either their biological or molecular properties, and how genetic polymorphisms may affect amplification assays. Different strains may only be present in certain geographical regions and resource sharing of biological samples from these regions, labs with the ability to characterize CWD strains, and labs with the ability to perform diagnostic assays to accomplish this goal.  

Objective #4: Evaluating Management Strategies across State Boundaries

We used a structured decision-making (SDM) process to develop a cross-jurisdictional research project that is aimed at evaluating strategies to manage CWD. Currently, we have 8 state agencies that will potentially participate in the experiment. Using the SDM, we developed a common understanding of the problem this effort will address, the associated objectives, the potential alternative action plans and ways to assess the impacts and trade-offs of our effort. We also have selected our preferred alternative. Now that this scoping phase is done, we are working on developing our implementation plan that will lay out the specific study design, establish methods for evaluation and data collection, identify funding sources, resource requirements and timelines for action. Once the implementation plan is complete, we will also seek formal approval from each state agency to participate. We will then begin the experiment which will be a long-term effort as required to assess efficacy.

Objective #5: Enhancing coordination, understanding, and communication of social science as it relates to CWD research and management.

A major challenge in successful CWD management and control is inadequate understanding and integration of social values, motivations, and attitudes that drive behaviors critical to disease management and how to promote these behaviors. Wildlife and cervid farming regulations can increase or decrease the spread of CWD, but their effectiveness depends on voluntary choices by relevant stakeholders (e.g., hunters, farmers, landowners). A need remains for improved understanding of what influences behaviors such as social values, motivations, and attitudes toward CWD and the interaction between the resulting behaviors and CWD management. Equally important is the need for scientific evaluation of the effectiveness of targeted and unified engagement strategies surrounding management and policy. We intend a multidisciplinary, multiagency, multistate approach to meeting these challenges through an iterative process that includes disease and management experts, social scientists, and stakeholders. To fill this need, we will continue to expand the number of social scientists that are part of the Consortium. We will use social science methods such as survey instruments, structured interviews, and expert elicitation to evaluate strategies to improve adoption of desired behaviors supportive of CWD management. Concurrently, we will be working to build new research proposals aimed at increasing the understanding of the human dimensions of CWD to inform decision-makers and behavior change efforts. Additionally, this objective will be linked to objective 4 to help in designing and evaluating the sociological module of the multi-state adaptive management project.

Objective #6: Characterization of CWD strains

One critical unanswered question highly relevant to CWD zoonotic risks is the number and distribution of existing CWD prion strains in North America. The literature indicates 4-5 relatively well characterized CWD strains in the US and Canada. More strains and variants likely evade detection due to inadequate surveillance studies of CWD strains and variants. 

The consortium will identify, develop and validate tools that distinguish CWD strains/isolates in North America. We will coordinate and collaborate to examine CWD tissue samples of farmed and free-ranging cervids harvested and systematically examine them for CWD strains.  

Objective #7: Environmental contamination by infectious prions

We will coordinate with the Objective 2 working group to identify and access contaminated facilities. Decommissioned cervid farms are ideal for this aim. Importantly, we will assist in identification of facilities with long-term prion persistence that are likely influenced by soil physical and chemical properties, as well as climatic factors (Yuan et al., 20189), so a single facility will not provide definitive answers to questions of persistence

Plant growth studies are time consuming and can be technically challenging. To avoid replicating effort amongst groups conducting such studies, members of Objective 7a will coordinate experiments and projects.

Lastly, a key goal of this group is development of ways to definitively answer the question of environmentally mediated CWD transmission from natural sources of contamination.

 

Measurement of Progress and Results

Outputs

• Disease Transmission and Pathogenesis–CWD Tissue Bioarchives: Comments: The USGS has developed an early version of an archive system with deployment of the Angular SPA frontend through Gitlab which picks up a gitlab-ci.yml build and deploy file and lives in the frontend codebase. The frontend is deployed to an AWS S3 bucket(s) one for beta and one for prod and served from those to their respective endpoints. Deployment of the NodeJS API is also done through Gitlab which picks up our gitlab-ci.yml build and deploy file and lives in the api codebase. The database was developed and connected to a Postgres 12.14 database and was hosted on a AWS RDS (https://aws.amazon.com/rds/). A robust Authentication and Authorization development has not yet been developed but will be a final component of a usable interface.
• Research facilities for controlled CWD transmission experiments Comments: The primary output will be building capacity and capability for CWD research, increasing our knowledge of the mechanisms of disease transmission. A secondary objective is to provide well characterized samples to support other objectives (Objectives 1, 3 and 6). A final output is new hypotheses, generated based upon the controlled laboratory studies, that can be translated to the field for testing.
• Improving Diagnostic Testing for CWD: Comments: CWD diagnostic testing has advanced by focusing on facilitating adoption of the RT-QuIC assay with commercially available substrates. The advancements include: personnel training, certifying laboratories, and developing protocols for suspect samples. We will standardize assays for specific sample types, data analysis, and terminology with a goal of submitting to NAHLN for assay approval. We will also develop a workflow for use of PMCA and/or RT-QuIC to facilitate sharing of resources for specific research projects.
• Evaluating Management Strategies across State Boundaries Comments: We will produce a document that describes the results of the scoping phase of the project. We will also provide an implementation plan, work to secure necessary approvals and funding, and initiate the experiment, analyze results and make management recommendations on the efficacy of evaluated management strategies.
• Enhancing coordination, understanding, and communication of social science as it relates to CWD research and managemen Comments: Outputs by the Consortium will result in the development of strategies for communicating the science on CWD, addressing the appropriate context and intention of the messaging, meeting the needs and motivations of stakeholder groups, and is consistent and clear across jurisdictions. The impact of varying engagement strategies across locations will be measured and linked to objective 4. This objective will produce knowledge about best practices in affecting positive behavioral change related to CWD and its management.
• Characterization of CWD strains Comments: The primary output will be methods for discriminating CWD strains and then deployment of these approaches to detect and identify CWD strains in cervid populations allowing us to ascertain the number of CWD strains, identify the distinctive features of each strain, provide data on the geographical distribution of strains, reveal correlations between CWD strain and PrP genotype(s), and suggest epidemiological links that could be targeted for management.
• Environmental contamination by infectious prions Comments: Initial outputs will be identification and coordination with Objective 2 to facilitate long-term prion persistence studies, generating an archive of environmental samples. Later outputs will be Consortium-led proposals to address the most salient questions of environmental prion disease: what is the total prion load being contributed into the environment by CWD infected animals, and to what extent is environmental transmission occurring in the wild?

Outcomes or Projected Impacts

• Disease Transmission and Pathogenesis–CWD Tissue Bioarchives Tissue repositories will provide access to CWD-positive tissue for strain identification and multiple research purposes. We developed SAGOTR as a resource and platform for gathering and sharing accessible CWD-positive tissues and identifying CWD strains (Objectives #3 & 6). Many CWD samples are not typed with respect to prion strain. With this in mind, SAGOTR represents the start of a substantial knowledge base that will strengthen CWD studies.
• Research facilities for controlled CWD transmission experiments Increased access to facilities will allow CWD scientists to effectively address key aspects of CWD management and ecology that are impossible to test without cervids and, thus, accelerate scientific progress. Researchers interested in studying CWD transmission, persistence, and management will have facilities to learn about these crucial aspects of the disease. State and federal wildlife agencies, wildlife biologists, and landowners will have knowledge they can use to manage cervids in the face of CWD and thereby reduce the impacts of the disease.
• Improving Diagnostic Testing for CWD Improving diagnostics for CWD may assist in detecting CWD earlier in the disease progression in cervids, in ante-mortem samples, and in the environment. Additionally, as prion amplification assays continue to develop and become refined, validation of such assays are necessary for their use in the management of wild and captive cervid populations and programs.
• Evaluating Management Strategies across State Boundaries Evaluation of the impacts of CWD management actions on both population and disease dynamics will guide agency planning and inform future management efforts. By including stakeholders in building a social science backbone to underpin the proposed CWD management research, we can evaluate various methods to improve stakeholder engagement in CWD and deer management programs. The cross-jurisdictional nature of this Objective is a unique example of collaborative research to manage a species and disease that do not respect jurisdictional boundaries, improving the likelihood of success within and across jurisdictions.
• Enhancing coordination, understanding, and communication of social science as it relates to CWD research and management This objective will lead to sustained and broad public/stakeholder support for research and management of CWD. This will be demonstrated through behavioral changes that are responsive to management recommendations and regulations, enhanced funding support, and increased collaborations across stakeholder groups. Hunter actions towards risk mitigation and deer harvest goals, and landowner access and participation will be critical for advancing management actions. Further outcomes include enhanced trust by the public and key stakeholder groups in management agency decisions and recommendations, implementation of science-based actions and policy, and effective CWD control and mitigation.
• Characterization of CWD strains Knowledge on the number, distinctive features, and geographic distribution of all (or vast majority) of existing CWD strains will allow us to better assess the CWD epidemic and enhance CWD surveillance, including monitoring of the spread and evolution of CWD strains between regions over time. Critically, it will also allow a more complete evaluation of zoonotic risk of CWD strains for sympatric species, including humans
• Environmental contamination by infectious prions Almberg et al. (2011) predict that the fate of cervids dependent on prion persistence in the environment. Developing true estimates of prion persistence across landscapes will allow for more accurate models. Estimates of true prion load release and persistence will also assist with remediation efforts by establishing baselines for treatment regimes. Likewise, sites for long term environmental work may be used for assessment of remediation technologies at field scale.

Milestones

(2025):Prepare and submit group research proposals. Proposals will be developed, based on available funding, in all years and research will be based on funding success. The Consortium will also respond to events in CWD research and management by developing white papers and other products based on the expertise of the membership--these will be produced as needed across the 5 years. Additional milestones in the first year will include: 1)Collection of physical samples at Fort Collins and online samples through SAGOTR. 2)Update research facility inventory. Explore needs, identify partners and consider strategy for an application to NIH for a facilities construction grant, PAR-25-061. 3) Develop standard protocols for commercially available substrates for RT-QuIC and PMCA testing of MRPLNs. Secure funding for validation studies of standardized protocols. 4)Develop implementation plan for multi-state adaptive management project. 5)Continue progress on existing multistate project regarding context dependent outreach and behavior change of hunters and landowners. 6) Develop a plan for cross-lab analysis of previously characterized CWD strains 7) Establish the environmental working group and the immediate plans for developing a Consortium-led proposal.

(2026):Prepare presentations and publications based on the previous years’ activity and research. Additional milestones in the second project year will include: 1) Broader connections with CWD researchers and wildlife biologists to provide samples for the tissue banks 2) Establish a policy for assessment of large-scale facilities 3) Complete a second RT-QuIC/PMCA multi-lab assay validation project. 4) Obtain approvals and resources for adaptive management project. Begin pretreatment phase of the project. 5) Develop and submit new research proposals that are aimed at increasing the understanding of the human dimensions of CWD to inform decision-makers and behavior change efforts. 6) Initiate cross-lab evaluations of CWD strains; establish criteria for strain identification 7)Analysis of environmental samples by members of the consortium

(2027):Prepare presentations and publications based on the previous years’ activity and research. Additional milestones in the third project year will include: 1)Submit a funding application to construct facilities that would enhance CWD transmission capabilities or capacity. 2)Create a comparison of prion amplification assay detection abilities for multiple sample types, including ante-mortem and environmental samples. 3)Initiate treatments as part of the adaptive management project and begin to measure impacts. 4)Secure funding for research proposals that are aimed at increasing the understanding of the human dimensions of CWD to inform decision-makers and behavior change efforts. 5)Assist objective #1 (tissue bank) with strain typing of samples of interest. Secure funding for strain typing of field isolates. 6)Develop a checklist for analysis of environmental samples (i.e., soil type/detection method) f

(2028):Prepare presentations and publications based on the previous years’ activity and research. Additional milestones in the fourth project year will include: 1)Create a comparison of prion amplification assay detection abilities for characterized CWD strains. 2)Continue treatments as part of the adaptive management project and measure impacts. 3)Provide guidance to agencies on best practices for outreach and education regarding CWD management. Provide guidance on effective strategies for improving landowners and hunters adoption of CWD management practices. 4) Begin analysis of strain data to determine if link between geography and strain; PRNP genotype and strain. 5)Cross-lab analysis of environmental samples

(2029):Prepare presentations and publications based on the previous years’ activity and research. Additional milestones in the fifth project year will include: Synthesize all information generated by the consortium over the past 5 years. Compile and submit a renewal of this multi-state program.

Projected Participation

View Appendix E: Participation

Outreach Plan

Our project will generate multiple peer-reviewed publications in disciplinary and impactful journals. We will also produce shorter communications for the public in professional magazines (e.g., The Wildlife Professional), on the project website, on partnering agency websites, and through respective land-grant university extension communications. Research presentations will be targeted to regional, national, and international conferences. Participants with an outreach and extension role will further disseminate progress and results to agency wildlife managers and the public through multimedia methods, including webinars, podcasts, and in-person events. Given the national importance of CWD, we anticipate project participants communicating results to state and federal agencies and legislatures.

Organization/Governance

Membership in the multistate project will be open to SAES scientists, other public and private sector scientists, extension professionals, administrative advisors, CSREES representatives, and others who are in a position to contribute to the proposed activities. Current members, including representatives from each member SAES, vote on the acceptance of new members. Voting membership is extended to new members upon a majority vote of the voting members. In addition to conducting the agreed-upon research collaboration, project members are responsible for reporting progress, contributing to the ongoing progress of project activities, and communicating their accomplishments to the committee members and their respective employing institutions.

All voting members of the committee are eligible for office, regardless of sponsoring agency affiliation. The executive committee consists of the officers:

Past chairs: The past chair will prepare the annual report for the year in which s/he served as chair. The past chairs will continue to participate on the executive committee, providing “institutional memory” for the consortium. The past chair will serve as chair in the absence of both the elected chair and vice-chair. The past chair may extend executive committee participation beyond one year.

Chair: In consultation with the administrative adviser, notifies the committee members of the time and place of meetings, prepares the agenda, presides at meetings of the committee and the executive committee. The chair is responsible for preparing or supervising the preparation of the quarterly and annual report of the project. The chair will serve a one-year term and will succeed to the past chair the following year.

Vice-chair: Succeeds the chair and is expected to carry out duties assigned by the chair. The chair-elect serves as the chair in the absence of the elected chair. The chair-elect will serve a one-year term and will succeed to the chair the following year.

Secretary: records the minutes and performs other duties assigned by the committee or the administrative advisor. The secretary shall be responsible for assisting the chair to prepare official communications to the administrative advisor, NIMSS, and other external parties. The secretary will serve a one-year term and succeed to the vice-chair the following year.

Subcommittees will be named by the chair as needed for specific assignments. This may include subcommittees to develop procedures, manuals, and phases of the regional project; to review work assignments; to develop research methods; and to prepare publications. Subcommittees have also formed to address each of the objectives, with designated Objective leads. The Objective leads will be responsible for communicating progress and roadblocks to the executive committee.

 

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Attachments

Land Grant Participating States/Institutions

AR, CO, MI, MN, MO, NY, SD, TN

Non Land Grant Participating States/Institutions

Arkansas Game and Fish Commission, Case Western Reserve University, Colorado State University, Creighton University, Idaho Fish and Game, Iowa Department of Natural Resources, Minnesota Department of Natural Resources, Texas A&M University - Kingsville, The University of Texas Health Science Center at Houston, University of Alberta, University of Calgary, University of Georgia, University of Minnesota, University of Pennslyvania, USDA Forest Service, USDA Wildlife Services, USDA-ARS/CO, USDA-ARS/Iowa, USDA-ARS/Washington, USDA/APHIS Veterinary Services, USDA/APHIS/WS/National Wildlife Research Center, USGS, USGS National Wildlife Health Center, Western Association of Fish and Wildlife Agencies, Wisconsin Department of Natural Resources