Detection of prions from spiked and free-ranging carnivore feces.

Chronic wasting disease (CWD) is a highly contagious, fatal neurodegenerative disease caused by infectious prions (PrPCWD) affecting wild and captive cervids. Although experimental feeding studies have demonstrated prions in feces of crows (Corvus brachyrhynchos), coyotes (Canis latrans), and cougars (Puma concolor), the role of scavengers and predators in CWD epidemiology remains poorly understood. Here we applied the real-time quaking-induced conversion (RT-QuIC) assay to detect PrPCWD in feces from cervid consumers, to advance surveillance approaches, which could be used to improve disease research and adaptive management of CWD. We assessed recovery and detection of PrPCWD by experimental spiking of PrPCWD into carnivore feces from 9 species sourced from CWD-free populations or captive facilities. We then applied this technique to detect PrPCWD from feces of predators and scavengers in free-ranging populations. Our results demonstrate that spiked PrPCWD is detectable from feces of free-ranging mammalian and avian carnivores using RT-QuIC. Results show that PrPCWD acquired in natural settings is detectable in feces from free-ranging carnivores, and that PrPCWD rates of detection in carnivore feces reflect relative prevalence estimates observed in the corresponding cervid populations. This study adapts an important diagnostic tool for CWD, allowing investigation of the epidemiology of CWD at the community-level.

Neuropathological, clinical and molecular pathology in female fragile X premutation carriers with and without FXTAS.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder associated with premutation alleles of the fragile X mental retardation 1 (FMR1) gene. Approximately 40% of older male premutation carriers, and a smaller proportion of females, are affected by FXTAS; due to the lower penetrance the characterization of the disorder in females is much less detailed. Core clinical features of FXTAS include intention tremor, cerebellar gait ataxia and frequently parkinsonism, autonomic dysfunction and cognitive deficits progressing to dementia in up to 50% of males. In this study, we report the clinical, molecular and neuropathological findings of eight female premutation carriers. Significantly, four of these women had dementia; of the four, three had FXTAS plus dementia. Post-mortem examination showed the presence of intranuclear inclusions in all eight cases, which included one asymptomatic premutation carrier who died from cancer. Among the four subjects with dementia, three had sufficient number of cortical amyloid plaques and neurofibrillary tangles to make Alzheimer's disease a highly likely cause of dementia and a fourth case had dementia with cortical Lewy bodies. Dementia appears to be more common than originally reported in females with FXTAS. Although further studies are required, our observation suggests that in a portion of FXTAS cases there is Alzheimer pathology and perhaps a synergistic effect on the progression of the disease may occur.

Factors and Outcomes in Primary Care Physician Retention in Rural Areas

Background: This paper examines factors influencing physicians' decisions to practise in rural communities as well as the results of a programme focused on rural recruitment and retention. Methods: Data from two sources were analysed and discussed: 1) telephone interviews with 20 of 33 (61) recently located rural physicians regarding practice and community factors influencing their practice decisions and 2) a database of 107 graduates of a rural medical education programme who have been in practice for at least three years to examine specialty choice and practice location(s); including moves from their original practice sites. Results: Most rural physicians in this study decided to practise in rural areas because of family ties. Eighty per cent of the physicians participating in the interviews mentioned no negative personal or family factors related to their community of practice. Outcome data on graduates from the rural medical education programme are encouraging. Over 70opt for primary care and rural practice. Over 80have remained in their original rural practice location. Conclusion: Keys to success in rural physician retention seem to include identifying and recruiting medical students ofrural origin and focusing on a healthy practice environment. Policy makers need to work with local government; schools and employers to offer programmes that provide information on health careers in rural areas and begin to identify local youth for induction in rural health care

Medical students' assessments of skill development in rural primary care clinics.

INTRODUCTION: This study assessed the impact of a rural primary care preceptorship on medical students' self-perceived ability to provide acute, chronic, and preventive care, to perform procedures, to communicate with patients, and to understand the community and healthcare system. METHODS: Students were surveyed about their self-assessed skills on 11 major components (97 items) immediately before and after a 16 week preceptorship in a rural primary care clinic. Responses were analyzed for 96 medical students using a paired comparisons t-test and univariate statistics. RESULTS: Students' skills significantly increased on all components and items. The skills most highly assessed post-preceptorship were those skills related to the management of chronic problems, the provision of patient education and health maintenance, and the ability to handle undifferentiated and acute problems. Among the 11 components assessed, students ranked their skills in performing procedures the lowest. The largest cumulative gain in skills was in the areas of understanding health systems and the community. CONCLUSIONS: This study provides a unique opportunity to look at skill development before and after a rural clerkship. From the student's perspective, the 16 week preceptorship appears to be of significant educational benefit. Future studies need to examine other measures of performance and outcomes of training in rural primary care settings.

Isolation of multiple Salmonella serovars from a dairy two years after a clinical salmonellosis outbreak.

Samples were obtained for bacteriologic culturing of salmonellae from cows and calves on, and the environment of, a large California dairy that used free-stall housing and a flush system for manure handling. Two years previously, the dairy had an outbreak of clinical salmonellosis in the lactating herd; however, since that time, it had not had problems with clinical salmonellosis. On the basis of mean annual milk production per cow, this dairy was consistently ranked in the top 25% of dairies in the area enrolled in the Dairy Herd Improvement Association. Results of bacteriologic culture of 76% (108/142) of environmental samples and 48% (639/1,339) of fecal samples were positive for salmonellae. Eighty-two percent of the isolates were serovar C1, subclassified as Salmonella montevideo, and 17% were serovar E. Results of bacteriologic culture of 85% of samples of recycled flush water being pumped into the free-stall alleys were positive, as were results of bacteriologic culture of 78% of samples of herd bulk milk filters, 97% of fecal samples collected from calves being fed nonsalable milk, and 25% of fecal samples collected from cows at the time of breeding. These findings suggest that freedom from clinical salmonellosis and comparatively high measures of herd performance do not indicate the absence of salmonellae from a premises, and that hardy infectious agents transmitted by ingestion of feces can become established in the environment of modern free-stall dairies that use recycled water in their manure flush systems.