After the loss and fragmentation of habitat, vehicle collisions are one of the main threats to the long-term survival of wild koalas. Koala road strike data were analysed for a section of the Peak Downs Highway between Nebo and Spencer's Gap, west of Mackay, Queensland, Australia. The analysis was carried out on 345 records (October 2014 to November 2023), and results suggested the spatial distribution of koala road strike followed a random pattern along this section of the highway, assuming a Poisson point pattern on a linear network.
View Article and Find Full Text PDFObjective: To identify the size and distribution of the horse population in the Northern Rivers Region of NSW, including changes from 2007 to 2021, to better understand populations at risk of Hendra virus transmission.
Methods: Census data from the 2007 Equine Influenza (EI) outbreak were compared with data collected annually by New South Wales Local Land Services (LLS) (2011-2021), and with field observations via road line transects (2021).
Results: The horse populations reported to LLS in 2011 (3000 horses; 0.
Coevolution is common and frequently governs host-pathogen interaction outcomes. Phenotypes underlying these interactions often manifest as the combined products of the genomes of interacting species, yet traditional quantitative trait mapping approaches ignore these intergenomic interactions. Devil facial tumor disease (DFTD), an infectious cancer afflicting Tasmanian devils (), has decimated devil populations due to universal host susceptibility and a fatality rate approaching 100%.
View Article and Find Full Text PDFInfectious diseases are strong drivers of wildlife population dynamics, however, empirical analyses from the early stages of pathogen emergence are rare. Tasmanian devil facial tumour disease (DFTD), discovered in 1996, provides the opportunity to study an epizootic from its inception. We use a pattern-oriented diffusion simulation to model the spatial spread of DFTD across the species' range and quantify population effects by jointly modelling multiple streams of data spanning 35 years.
View Article and Find Full Text PDFIdentifying the genetic architecture of complex phenotypes is a central goal of modern biology, particularly for disease-related traits. Genome-wide association methods are a classical approach for identifying the genomic basis of variation in disease phenotypes, but such analyses are particularly challenging in natural populations due to sample size difficulties. Extensive mark-recapture data, strong linkage disequilibrium and a lethal transmissible cancer make the Tasmanian devil (Sarcophilus harrisii) an ideal model for such an association study.
View Article and Find Full Text PDFUnderstanding viral transmission dynamics within populations of reservoir hosts can facilitate greater knowledge of the spillover of emerging infectious diseases. While bat-borne viruses are of concern to public health, investigations into their dynamics have been limited by a lack of longitudinal data from individual bats. Here, we examine capture-mark-recapture (CMR) data from a species of Australian bat (Myotis macropus) infected with a putative novel Alphacoronavirus within a Bayesian framework.
View Article and Find Full Text PDFEmerging infectious diseases rarely affect all members of a population equally and determining how individuals' susceptibility to infection is related to other components of their fitness is critical to understanding disease impacts at a population level and for predicting evolutionary trajectories. We introduce a novel state-space model framework to investigate survival and fecundity of Tasmanian devils (Sarcophilus harrisii) affected by a transmissible cancer, devil facial tumour disease. We show that those devils that become host to tumours have otherwise greater fitness, with higher survival and fecundity rates prior to disease-induced death than non-host individuals that do not become infected, although high tumour loads lead to high mortality.
View Article and Find Full Text PDFBackground: The benign reputation of Plasmodium vivax is at odds with the burden and severity of the disease. This reputation, combined with restricted in vitro techniques, has slowed efforts to gain an understanding of the parasite biology and interaction with its human host.
Methods: A simulation model of the within-host dynamics of P.
The preferential invasion of particular red blood cell (RBC) age classes may offer a mechanism by which certain species of Plasmodia regulate their population growth. Asexual reproduction of the parasite within RBCs exponentially increases the number of circulating parasites; limiting this explosion in parasite density may be key to providing sufficient time for the parasite to reproduce, and for the host to develop a specific immune response. It is critical that the role of preferential invasion in infection is properly understood to model the within-host dynamics of different Plasmodia species.
View Article and Find Full Text PDFPurpose: To compare breast cancer subtyping with the three centrally assessed microarray-based assays BluePrint, MammaPrint, and TargetPrint with locally assessed clinical subtyping using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH).
Methods: BluePrint, MammaPrint, and TargetPrint were all performed on fresh tumor samples. Microarray analysis was performed at Agendia Laboratories, blinded for clinical and pathological data.
The emergence of highly chloroquine (CQ) resistant P. vivax in Southeast Asia has created an urgent need for an improved understanding of the mechanisms of drug resistance in these parasites, the development of robust tools for defining the spread of resistance, and the discovery of new antimalarial agents. The ex vivo Schizont Maturation Test (SMT), originally developed for the study of P.
View Article and Find Full Text PDFSkeletal muscles in hypertensive subjects develop an increased resistance to insulin that reduces their ability to incorporate glucose and synthesize glycogen. Insulin is an anabolic hormone in muscle, and muscle insulin receptors bind the growth factor, insulin-like growth factor I (IGF-I), an important contributor to muscle development and regeneration. An increase in insulin resistance in hypertensive subjects might produce muscle atrophy and weakness or limit regenerative growth after injury.
View Article and Find Full Text PDFEight patients with cystic neoplasms of the pancreas were seen at four Northern California hospitals between the years 1978 and 1986. Three of the tumors were benign and five were malignant. Three females, whose average age was 61 years, had cystadenomas.
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