White-nose syndrome is caused by the fungus Pseudogymnoascus destructans and has killed millions of hibernating bats in North America but the pathophysiology of the disease remains poorly understood. Our objectives were to (1) assess non-destructive diagnostic methods for P. destructans infection compared to histopathology, the current gold-standard, and (2) to evaluate potential metrics of disease severity. We used data from three captive inoculation experiments involving 181 little brown bats (Myotis lucifugus) to compare histopathology, quantitative PCR (qPCR), and ultraviolet fluorescence as diagnostic methods of P. destructans infection. To assess disease severity, we considered two histology metrics (wing area with fungal hyphae, area of dermal necrosis), P. destructans fungal load (qPCR), ultraviolet fluorescence, and blood chemistry (hematocrit, sodium, glucose, pCO2, and bicarbonate). Quantitative PCR was most effective for early detection of P. destructans, while all three methods were comparable in severe infections. Correlations among hyphae and necrosis scores, qPCR, ultraviolet fluorescence, blood chemistry, and hibernation duration indicate a multi-stage pattern of disease. Disruptions of homeostasis occurred rapidly in late hibernation. Our results provide valuable information about the use of non-destructive techniques for monitoring, and provide novel insight into the pathophysiology of white-nose syndrome, with implications for developing and implementing potential mitigation strategies.

In the UK, there have been few studies of the seroprevalence of antibodies to hepatitis C virus (anti-HCV). As part of an ongoing prevalence study of HCV in injecting drug users, we have developed a technique for detecting anti-HCV in blood spots dried on filter paper using a commercially available assay. Subjects with and without serum anti-HCV were studied. The manufacturer's recommended cut-off (CO) for a positive anti-HCV result is kit-dependent, and therefore a ratio of test result (T) to kit CO was used to standardize results. T/CO values greater than 0.99 had a sensitivity of 100% and a specificity of 87.5% for anti-HCV detection. T/CO values greater than 1.99 had a sensitivity of 97.2% and a specificity of 100%. Hence, testing dried blood spots may be useful for detecting anti-HCV in epidemiological studies and as a diagnostic test in patients with poor peripheral venous access.

An approximately six-month-old wild American black bear (Ursus americanus) was found wandering in Saskatchewan and was presented to the Veterinary Medical Centre of the Western College of Veterinary Medicine for apparent blindness. Clinical examination confirmed an inability to navigate a photopic maze, bilateral tapetal hyper-reflectivity, fundi devoid of retinal vessels, and small pale optic nerve papillae. Single-flash electroretinography revealed A and B-wave amplitudes of approximately 40 and 140 microvolts, respectively, in both eyes. Histologic abnormalities included bilateral optic papillary mineralization and bilateral segmental optic nerve degeneration, with occasional intralesional lymphocytes confirmed with immunohistochemistry for CD3+. There was also bilateral multifocal retinal dysplasia, gliosis, lymphocytic retinitis, a complete lack of retinal blood vessels, an intravitreal vascular membrane, and a mild lymphocytic-plasmacytic uveitis with small pre-iridal cellular membranes. The presence of a positive ERG in a blind bear with numerous retinal ganglion cells and degenerative changes in the optic nerve are most consistent with vision loss due to optic nerve injury, which given the young age of the bear likely occurred during ocular development. The presence of ocular inflammation suggests this injury resulted from an inflammatory/infectious process. The etiology could not be determined. Hepatic concentrations of vitamin A were within the normal reference range for domestic species. Pan-herpesvirus PCR and immunohistochemistry for canine distemper virus and Toxoplasma gondii were negative, although this does not rule out these or other infectious etiologies. This represents the first case report of neonatal or congenital ocular abnormalities in an ursid species.

A complete 30,616 nucleotide Cervid atadenovirus A genome was determined from tissues of a black-tailed deer that died in 2020 in British Columbia, Canada. Unique, non-synonymous SNPs in the E1B, Iva2 and E4.3 coding regions, and deletions totaling 74 nucleotides not observed in moose and red deer isolates were present.

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