BackgroundAngiostrongylus mackerrasae is a metastrongyloid nematode endemic to Australia, where it infects the native bush rat, Rattus fuscipes. This lungworm has an identical life cycle to that of Angiostrongylus cantonensis, a leading cause of eosinophilic meningitis in humans. The ability of A. mackerrasae to infect non-rodent hosts, specifically the black flying fox, raises concerns as to its zoonotic potential. To date, data on the taxonomy, epidemiology and population genetics of A. mackerrasae are unknown. Here, we describe the mitochondrial (mt) genome of A. mackerrasae with the aim of starting to address these knowledge gaps.MethodsThe complete mitochondrial (mt) genome of A. mackerrasae was amplified from a single morphologically identified adult worm, by long-PCR in two overlapping amplicons (8 kb and 10 kb). The amplicons were sequenced using the MiSeq Illumina platform and annotated using an in-house pipeline. Amino acid sequences inferred from individual protein coding genes of the mt genomes were concatenated and then subjected to phylogenetic analysis using Bayesian inference.ResultsThe mt genome of A. mackerrasae is 13,640 bp in size and contains 12 protein coding genes (cox1-3, nad1-6, nad4L, atp6 and cob), and two ribosomal RNA (rRNA) and 22 transfer RNA (tRNA) genes.ConclusionsThe mt genome of A. mackerrasae has similar characteristics to those of other Angiostrongylus species. Sequence comparisons reveal that A. mackerrasae is closely related to A. cantonensis and the two sibling species may have recently diverged compared with all other species in the genus with a highly specific host selection. This mt genome will provide a source of genetic markers for explorations of the epidemiology, biology and population genetics of A. mackerrasae.

Despite the recent sporadic reports of angiostrongyliasis in humans, dogs and wildlife in eastern Australia there has been no systematic study to explore the epidemiology of Angiostrongylus spp. in definitive and intermediate hosts in the region. Little is known about the epidemiology of Angiostrongylus species in the definitive host in southeast Queensland, since the only survey conducted in this region was performed in the late 1960s. In this study, free-living populations of Rattus spp. were sampled and examined for the presence of adult and larval Angiostrongylus in the lungs, and of larvae in faeces. The prevalence of infection with Angiostrongylus spp. was 16.5% in Rattus spp. trapped in urban Brisbane and surrounds. This prevalence is much higher than estimates of earlier studies. This highlights the possible risk of zoonotic infection in children, dogs and wildlife in this region and indicates the necessity for public awareness as well as more detailed epidemiological studies on this parasite in eastern Australia.

Despite an apparent increase in cases of angiostrongyliasis in humans and animals in Australia, the epidemiology of infection with the two species of Angiostrongylus that co-exist in this country, namely A. cantonensis and A. mackerrasae, is poorly understood. This knowledge gap is particularly important with respect to A. mackerrasae, a species evidently native to Australia, as its ability to cause disease in humans is unknown. Likewise, there is little information on the roles of native and introduced species of rodents and molluscs as hosts of Angiostrongylus species in Australia. This review focuses on the gaps in the knowledge about the two species, highlighting the need for epidemiological and pathogenesis studies on the native lungworm A. mackerrasae.

(1) Background: soil-transmitted helminths are a problem worldwide, largely affecting disadvantaged populations. The little data available indicates high rates of infection in some remote Aboriginal communities in Australia. Studies of helminths were carried out in the same remote community in the Northern Territory in 1994–1996 and 2010–2011; (2) Methods: fecal samples were collected from children aged <10 years and examined for helminths by direct smear microscopy. In the 2010–2011 study, some fecal samples were also analyzed by agar plate culture and PCR for Strongyloides stercoralis DNA. Serological analysis of fingerprick dried blood spots using a S. stercoralis NIE antigen was also conducted; (3) Results and Conclusions: a reduction in fecal samples positive for S. stercoralis, hookworm and Trichuris trichiura was seen between the studies in 1994–1996 and 2010–2011, likely reflecting public health measures undertaken in the region to reduce intestinal helminths. Comparison of methods to detect S. stercoralis showed that PCR of fecal samples and serological testing of dried blood spots was at least as sensitive as direct smear microscopy and agar plate culture. These methods have advantages for use in remote field studies.

Australia has a highly localised but diverse radiation of microhylid frogs. 18 species are described from north-east Queensland (14 Cophixalus and 4 Austrochaperina), most with highly localised montane distributions. While most species are small (10-25 mm) rainforest species, two differ dramatically in ecology and morphology. Cophixalus saxatilis and C. zweifeli inhabit isolated areas of jumbled boulder-pile habitat and are considerably larger than all other species (30-45 mm). Here we describe two new species of large, boulder dwelling Cophixalus from the Pascoe River region of Cape York Peninsula. Cophixalus kulakula sp. nov. occurs in piled boulder habitat amongst rainforest in the Tozer Range area, while Cophixalus pakayakulangun sp. nov. occurs in similar habitat in the Kennedy Hills region north of the Pascoe River. These are the most northerly sites for Cophixalus in Australia and both occur in rainforest areas not occupied by other species of Cophixalus. Both species are large (snout-vent length > 40 mm) and of similar morphology to the other two boulder-dwelling species. Cophixalus kulakula sp. nov. and C. pakayakulangun sp. nov. differ from each other and from all other described Cophixalus genetically and in aspects of colour pattern and morphology. The call of C. kulakula sp. nov. is also unique, but the call of C. pakayakulangun sp. nov. remains unknown. The two new species are each others closest relatives (albeit with approximately 8% genetic divergence for 12S and 16S mtDNA) and are allied to C. ornatus. The diet of both species consists primarily of ants. Both species have highly localised distributions but are abundant within these and are probably secure.