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Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused by Ophidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts. [ABSTRACT FROM AUTHOR]

Disease can play an important role in structuring species communities because the effects of disease vary among hosts; some species are driven towards extinction, while others suffer relatively little impact. Why disease impacts vary among host species remains poorly understood for most multi-host pathogens, and factors allowing less-susceptible species to persist could be useful in conserving highly affected species. White-nose syndrome (WNS), an emerging fungal disease of bats, has decimated some species while sympatric and closely related species have experienced little effect. We analysed data on infection prevalence, fungal loads and environmental factors to determine how variation in infection among sympatric host species influenced the severity of WNS population impacts. Intense transmission resulted in almost uniformly high prevalence in all species. By contrast, fungal loads varied over 3 orders of magnitude among species, and explained 98% of the variation among species in disease impacts. Fungal loads increased with hibernating roosting temperatures, with bats roosting at warmer temperatures having higher fungal loads and suffering greater WNS impacts. We also found evidence of a threshold fungal load, above which the probability of mortality may increase sharply, and this threshold was similar for multiple species. This study demonstrates how differences in behavioural traits among species--in this case microclimate preferences--that may have been previously adaptive can be deleterious after the introduction of a new pathogen. Management to reduce pathogen loads rather than exposure may be an effective way of reducing disease impact and preventing species extinctions. [ABSTRACT FROM AUTHOR]

Different murine species differ in their susceptibility to systemic infection with Candida albicans, giving rise to varied host immune responses, and this is compounded by variations in virulence of the different yeast strains used. Hence, this study was aimed at elucidating the pathogenesis of a clinical C. albicans isolate (HVS6360) in a murine intravenous challenge model by examining the different parameters which included the counts of red blood cells and associated components as well as the organ-specific expression profiles of cytokines and chemokines. Kidneys and brains of infected mice have higher fungal recovery rates as compared to other organs and there were extensive yeast infiltration with moderate to severe inflammation seen in kidney and brain tissues. Red blood cells (RBCs) and haemoglobin (Hb) counts were reduced throughout the infection period. Pattern recognition receptors (PRRs), chemokines and cytokine transcription profiles were varied among the different organs (kidney, spleen and brain) over 72 h post infections. Transcription of most of the PRRs, cytokines and chemokines were suppressed at 72 h post infection in spleen while continuous expression of PRRs, cytokines and chemokines genes were seen in brain and kidney. Reduction in red blood cells and haemoglobin counts might be associated with the action of extracellular haemolysin enzyme and haeme oxygenase of C. albicans in conjunction with iron scavenging for the fungal growth. Renal cells responsible for erythropoietin production may be injured by the infection and hence the combined effect of haemolysis plus lack of erythropoietin-induced RBC replenishment leads to aggravated reduction in RBC numbers. The varied local host immune profiles among target organs during systemic C. albicans infection could be of importance for future work in designing targeted immunotherapy through immunomodulatory approaches. [ABSTRACT FROM AUTHOR]

The author discusses the causes of white-nose syndrome (WNS) in bats referring to Geomyces destructans as the cause of mass mortality and large-scale population declines of certain bat species. The author highlights another finding wherein G. destructans have not caused mass mortality in wild European bats, in contrast to bats in North America with WNS. Moreover, the author is particular on fungal-influences and hyper-frequent arousal from hibernation as the cause of death in WNS bats.

The article describes two cases of feline orbital aspergillosis caused by Aspergillus udagawae and Aspergillus viridinutans. An overview of other reported feline cases of orbital aspergillosis is presented. It discusses the materials and methods used in both cases, the comparative sequence analysis and molecular analysis results obtained in the case study, and other findings obtained after diagnosing the subjects using histopathologic examination and mycological identification.

T helper (Th)1 and Th2 cells play decisive roles in the regulation of resistance vs. susceptibility to pulmonary cryptococcosis. To study the function of interleukin (IL)-4 receptor (IL-4R) on Th cells in pulmonary cryptococcosis, we infected mice specifically lacking IL-4Rα on CD4+ T cells (LckCreIL-4Rα−/lox mice) and IL-4Rα−/lox controls. LckCreIL-4Rα−/lox mice developed enhanced resistance accompanied by reduced pulmonary allergic inflammation and diminished production of the Th2 cytokines IL-4, IL-5, and IL-13 as compared with IL-4Rα−/lox mice. Polyfunctional antigen-specific Th2 cells producing simultaneously two or three Th2 cytokines were reduced in infected LckCreIL-4Rα−/lox mice, pointing to a critical role of polyfunctional Th2 cells for disease progression. Reduced Th2 polyfunctionality was associated with fewer pulmonary alternatively activated macrophages. This work is the first direct evidence for a critical contribution of the IL-4R on Th cells to Th2-dependent susceptibility during allergic bronchopulmonary mycosis. Moreover, the data demonstrate that the quality of the Th2 response has an impact on type 2 inflammation. The analysis of polyfunctional Th2 cells may be useful for monitoring the course of the disease. [ABSTRACT FROM AUTHOR]

Cryptococcosis is a systemic, subacute to chronic mycosis, potentially fatal, affecting domestic and wild mammals, and humans (Queiroz et al., 2008).It is caused by the yeast belonging to the genus Cryptococcus, an opportunistic and ubiquitous pathogen that has tropism for the central nervous system (CNS), eye, lymph nodes and skin (Marcasso et al., 2005). In this study, we report a Cryptococcus sp. natural infection in the Chinchilla lanigera. The animal was attended at the Veterinary Hospital, Federal University of Paraná, Curitiba with a history of poor appetite and decreased bowel motility. The diagnosis was made by histopathologic evaluation of cecum sections which had pyogranulomatous, typhilitis with intralesional yeasts. Infection by this fungus has never been reported in chinchillas, as long as we know and the gastrointestinal infection is an uncommon site of lesion in animals and humans (Juan-Salk et al., 2003). [ABSTRACT FROM AUTHOR]