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Melioidosis is a severe infectious disease caused by gram-negative, facultative intracellular pathogen Burkholderia pseudomallei (B. pseudomallei). Although cases are increasing reported from other parts of the world, it is an illness of tropical and subtropical climates primarily found in southeast Asia and northern Australia. Because of a 40% mortality rate, this life-threatening disease poses a public health risk in endemic area. Early detection of B. pseudomallei infection is vital for prognosis of a melioidosis patient. In this study, a novel isothermal recombinase polymerase amplification combined with lateral flow dipstick (LF-RPA) assay was established for rapid detection of B. pseudomallei. A set of primer-probe targeting orf2 gene within the putative type III secretion system (T3SS) cluster genes was generated and parameters for the LF-RPA assay were optimized. Result can be easy visualized in 30 minutes with the limit of detection (LOD) as low as 20 femtogram (fg) (ca. 25.6 copies) of B. pseudomallei genomic DNA without a specific equipment. The assay is highly specific as no cross amplification was observed with Burkholderia mallei, members of the Burkholderia cepacia-complex and 35 non-B. pseudomallei bacteria species. Moreover, isolates from patients in Hainan (N = 19), Guangdong (N = 1), Guangxi (N = 3) province of China as well as in Australia (N = 3) and Thailand (N = 1) were retrospectively confirmed by the newly developed method. LODs for B. pseudomallei-spiked soil and blood samples were 2.1×103 CFU/g and 4.2×103 CFU/ml respectively. The sensitivity of the LF-RPA assay was comparable to TaqMan Real-Time PCR (TaqMan PCR). In addition, the LF-RPA assay exhibited a better tolerance to inhibitors in blood than TaqMan PCR. Our results showed that the LF-RPA assay is an alternative to existing PCR-based methods for detection of B. pseudomallei with a potentiality of early accurate diagnosis of melioidosis at point of care or in-field use. [ABSTRACT FROM AUTHOR]

Fungi are increasingly being documented as causing disease in a wide range of faunal species, including Pseudogymnoascus destructans, the fungus responsible for white nose syndrome which is having a devastating impact on bats in North America. The population size of the Australian southern bent-winged bat (Miniopterus orianae bassanii), a critically endangered subspecies, has declined over the past 50 years. As part of a larger study to determine whether disease could be a contributing factor to this decline, southern bent-winged bats were tested for the presence of a range of potentially pathogenic fungi: P. destructans, dermatophytes and Histoplasma capsulatum (a potential human pathogen commonly associated with caves inhabited by bats). Results were compared with those obtained for the more common eastern bent-winged bat (M. orianae oceanensis). All bats and their environment were negative for P. destructans. A large number of fungi were found on the skin and fur of bats, most of which were environmental or plant associated, and none of which were likely to be of significant pathogenicity for bats. A 0–19% prevalence of H. capsulatum was detected in the bat populations sampled, but not in the environment, indicative of a low zoonotic risk. Based on the results of this study, fungi are unlikely to be contributing significantly to the population decline of the southern bent-winged bat. [ABSTRACT FROM AUTHOR]

An online survey was conducted to determine associations between transport management and transport-related injuries and diseases in horses in Australia. The survey was composed of three sections: respondents’ demographic information, transport management strategies or procedures (before, during and after transportation) and transport diseases experienced in the previous two year period. Univariate and multivariate modelling was performed exploring associations between variables (respondents’ details and transport management strategies) and the following transport-related diseases as outcomes: traumatic injuries, diarrhoea, heat stroke, muscular problems, laminitis, transport pneumonia and colic. The survey generated 797 responses. Traumatic injuries were the most common transport-related problem, with a reported incidence of 45.0%. Younger respondents (<40 years old) caring for large numbers of horses (>30 in a week) were more likely to report transport-related injuries. Injury risk was also linked to the use of protections and tranquilizers prior to transport, and checking horses after the journey. Diarrhoea (20.0%) and heat stroke (10.5%) were reported more by amateur than professional horse carers. Increased risk of heat stroke was linked to the restriction of hay and water prior to transportation. Muscular problems (13.0%) appeared to be exacerbated when horse health was not assessed before journey; whilst the risk of laminitis (2.9%) was around three fold greater when post transport recovery strategies were not applied. Associations were made between transport pneumonia (9.2%) and duration of journey, and with activity (horses involved in racing at greater risk). No associations were seen between the incidence of colic (10.3%) and the variables examined. Study findings should be interpreted with caution as they represent participant perceptions and recall. Nevertheless, results support many current recommendations for safe transportation of horses. They also highlight the need to further investigate many of identified management factors to refine existing policies and practices in equine transportation. [ABSTRACT FROM AUTHOR]

Australia has a fossil record of penguins reaching back to the Eocene, yet today is inhabited by just one breeding species, the little penguin Eudyptula minor. The description of recently collected penguin fossils from the re-dated upper Miocene Port Campbell Limestone of Portland (Victoria), in addition to reanalysis of previously described material, has allowed the Cenozoic history of penguins in Australia to be placed into a global context for the first time. Australian pre-Quaternary fossil penguins represent stem taxa phylogenetically disparate from each other and E. minor, implying multiple dispersals and extinctions. Late Eocene penguins from Australia are closest to contemporaneous taxa in Antarctica, New Zealand and South America. Given current material, the Miocene Australian fossil penguin fauna is apparently unique in harbouring ‘giant penguins’ after they went extinct elsewhere; and including stem taxa until at least 6 Ma, by which time crown penguins dominated elsewhere in the southern hemisphere. Separation of Australia from Antarctica during the Palaeogene, and its subsequent drift north, appears to have been a major event in Australian penguin biogeography. Increasing isolation through the Cenozoic may have limited penguin dispersal to Australia from outside the Australasian region, until intensification of the eastwards-flowing Antarctic Circumpolar Current in the mid-Miocene established a potential new dispersal vector to Australia. [ABSTRACT FROM AUTHOR]