Conference Agenda

Parasites are a part of everyone’s life; they infect our pets, the meat and crops we eat, and us. They also infect our iconic marsupial wildlife and the fish in our unique oceans and reefs, sometimes with devastating consequences. Australia, like everywhere else, also has a large number of common, human parasites, particularly in our remote communities. Some of these can be chronic, incapacitating and even life-threatening. Bernard Lee Singleton’s magnificent painting, Gula Guri mayin (which means “Heal the body”), explores themes of parasites and health. The Australian Society for Parasitology is known for its inspirational and groundbreaking outreach programs over the past two decades using games, art and technology to encourage new and innovative ways of engaging with audiences in the science of parasites. ASP researchers have developed and delivered hands-on activities to engage audiences in science and communicate about parasites and their impact on people in Australia and around the world. In this presentation audience survey data collected over 20 years will be presented to investigate changes in themes, styles and audiences of the ASP outreach program. Be inspired, delighted and maybe you'll be reminising along with the presenter, and finish with some hands-on fun!

Preparing the One Health workforce to detect and respond to zoonotic and parasitic disease threats demands practised, integrated decision-making across human, animal, and environmental health sectors. Australia's only veterinary school with a working farm on campus, Murdoch University co-locates a teaching veterinary hospital, research farm, bushland and wetland reserves, and public health facilities within walking distance of metropolitan hospitals, providing a natural living laboratory for parasitology and zoonotic disease surveillance training. BMS501 Zoonoses, Pandemic Surveillance and Preparedness is a core unit within Murdoch's Master of Infectious Disease Surveillance and Control. Field and laboratory practicals use the campus environment directly, with students conducting real sample collection, parasite identification, and vector surveillance across human, animal, and environmental interfaces on site. Students build preparedness plans, One Health stakeholder maps, and risk communication products in team-based workshops. Indigenous-led teaching anchors the unit in culturally safe governance and First Nations perspectives on surveillance. The unit culminates in a large-scale simulated outbreak using the EpiGames mobile application, opened to staff and students from human health, veterinary, and environmental science backgrounds. When the human, animal, and environmental health interfaces are literally on campus, authentic One Health parasitology training becomes possible.

Home‑school groups often face challenges in delivering science education, including limited access to specialised equipment and reduced confidence among parents when teaching complex concepts. These gaps create a valuable opportunity for researchers and academics to contribute their expertise through outreach, bringing authentic, hands‑on science experiences directly to learners.

A series of Microbes & Parasites Workshops (n=7), developed and delivered by a parasitologist and supported by the Engaging Children in Science (ECIS) STEM volunteer team, demonstrates this impact across Western Australia. The workshops have reached home‑school groups in Ocean Reef (2021), Baskerville (2022), Midland (2024, 2026), Izzelle’s (2025) and Gwelup (2026). Each session blends hands‑on science with creative STEAM activities, drawing on expertise in diagnostic microbiology, infectious diseases research and science communication. Through interactive demonstrations, storytelling and visual exploration, learners investigate bacteria, fungi, viruses and parasites, discovering how microbes shape human health and the environment.

Aligned with the WA Science Curriculum, the workshops build curiosity, scientific thinking through inquiry, observation and age‑appropriate experimentation. The inclusive approach supports diverse learners, including children aged 4–16 and those with ADHD and autism, to ask questions, think critically and see themselves as young scientists. Challenges, insights and impact from this work will be shared.

Artificial tick feeding systems (ATFS) provide ethical alternatives to in vivo models for studying tick biology, yet their application remains largely restricted to a few species. Ixodes hirsti, an Australian marsupial tick, remains understudied due to challenges in maintaining its life cycle under laboratory conditions. Here, we report the first successful in vitro feeding of I. hirsti larvae, and microbiome profiling combined with morphological characterisation of moulted nymphs. Larvae derived from field-collected engorged females were fed using silicone membrane supplemented with raw kangaroo hair and/or hair extract. Microbiome composition of the larvae was assessed using 16S rRNA amplicon sequencing. Nymphs were characterised using morphological (scanning electron microscopy) and molecular (targeting mitochondrial markers – cox1 and 16S) approaches. Attachment success differed significantly among treatments (p = 0.001), with hair extract yielding the highest attachment rate (71%). However, kangaroo hair improved feeding performance, reducing time to engorgement (9.17 ± 0.72 days) and increasing engorgement weight (0.91 ± 0.01 mg). Blood feeding reduced microbial richness and evenness, increased microbiome variability (p < 0.001), and enriched Stenotrophomonas, suggesting feeding-associated shifts in microbial composition. This study provides a proof-of-concept for a host-free platform for studying Australian wildlife ticks, enabling controlled investigations of vector biology and tick–microbe interactions.

Malaria continues to be a major cause of illness and death worldwide. Although efforts to develop a malaria vaccine date back to the 1940s, achieving a highly effective formulation that provides durable protection has remained a significant challenge.

Our work has shown that a chemically attenuated, whole parasite blood-stage malaria vaccine can elicit robust, CD4+ T cell–dependent immunity that protects against diverse malaria parasite strains in pre-clinical rodent models. In malaria-naïve human volunteers, a similar chemically attenuated Plasmodium falciparum blood-stage vaccine prevented the onset of blood-stage infection in a subset of individuals following controlled blood-stage parasite challenge. To our knowledge, this represents the first instance in which a blood-stage malaria vaccine has completely averted infection in human volunteers.

Despite these promising findings, the use of chemically attenuated parasites in endemic settings is constrained by various practical and logistical considerations. To address these limitations, we reformulated the vaccine by incorporating blood-stage parasites into liposomes. In rodent models, a whole blood-stage parasite liposomal formulation retained high efficacy after freezing or lyophilisation, supporting its suitability for field deployment.

Building on these results, we extended this platform to the related apicomplexan parasite Babesia, which causes babesiosis in humans as well as in livestock and companion animals. A lyophilised, liposome-based whole-parasite Babesia blood-stage vaccine induced strong cross-species protection in rodent models, highlighting its potential for both human and veterinary use.

Both the malaria- and babesiosis liposomal vaccine candidates are now advancing into clinical trials.

On an annual basis >300 million people develop giardiasis, a disease that impacts child development and the long-term health of many adults. However, there is no vaccine for this disease and treatment options are failing due to multiple factors including drug resistant parasites. Moreover, current treatment strategies are monotherapies that do little to combat the development of drug resistance. To improve this position combination therapies that include new compounds with unique mechanisms of action are needed. However, little has been done to identify best practice combination therapies for giardiasis.

As a mechanism to pave the way towards the development of highly effective therapies for giardiasis we have been investigating the activity of novel compounds and compound combinations against Giardia parasites in vitro. These studies have identified multiple synergistic compound combinations that may be useful in the in vivo including combinations that have Interaction (I) values >3.0 (p<0.05). While in vivo studies are now needed to determine how these combination therapies work in clinical settings, taken together with pharmacokinetic data, these results are exciting and suggest that novel antigiardial combination therapies can be developed to help combat treatment refractory giardiasis.

Toxoplasma gondii causes ocular toxoplasmosis, a vision-threatening retinal infection. Current therapeutics are not curative. ELQs are promising drugs not yet evaluated for ocular toxoplasmosis.

Human retinal pigment epithelial cells (ARPE-19 line) were infected with T. gondii GT-1 or GPHT tachyzoites and treated with ELQ-316 or ELQ-685. Tachyzoite growth 50% inhibitory concentrations (IC_50s) were calculated. Tachyzoite invasion, replication, and egress were assayed. Cell viability was evaluated by XTT assay. Cell response transcripts were measured by RT-qPCR.

ELQ IC_50s for GT-1 and GPHT were nanomolar-range and approximately equivalent (ELQ-316: 22.96±4.33nM vs. 21.23±3.92nM; ELQ-685: 1.08±0.34nM vs. 0.88±0.20nM; unpaired t-test, p>0.05). Both treatments significantly reduced replication (tachyzoites/rosette: ELQs ≤1.77±0.07 vs. untreated ≥6.85±0.66, p<0.0001; one-way ANOVA). Tachyzoite invasion and egress were not impacted by either drug. ELQs ≤12µM did not reduce cell viability (mitochondrial respiration (arbitrary units): ELQ 12µM 2.37±0.13 vs. untreated 2.19±0.07; p>0.05; one-way ANOVA). In GT-1-infected cells, ELQ treatment reduced 7 transcripts (CCL2, CXCL8, ICAM1, IL1B, IL6, NFKB1, PDCD1LG2; p≤0.0042) and increased 3 transcripts (CXCL10, TGFB2, VCAM1; p≤0.0048), versus untreated controls (one-way ANOVA). In GPHT-infected cells, ELQ treatment reduced 5 transcripts (CXCL8, ICAM1, IL6, NFKB1, REL; p≤0.043).

ELQs were non-toxic in ARPE-19 cells, reduced T. gondii replication, and altered host inflammatory mediator expression.

Plasmodium falciparum, the deadliest human malaria parasite, has developed resistance to all clinically used antimalarials, highlighting the need for new compounds with novel modes of action. Pantothenate analogues kill P. falciparum by targeting the biosynthesis or utilisation of coenzyme A (CoA), an essential enzyme cofactor. Pantothenamides (PanAms), pantothenate analogues in which the carboxyl group is replaced by an amide group, exhibit potent in vitro activity. Unfortunately, PanAms are degraded in vivo by human pantetheinase. Modification of the labile amide bond has given rise to pantetheinase-resistant PanAm mimics. AH-2-45, a ring-substituted PanAm mimic, exhibits nanomolar antiplasmodial activity and is metabolised by CoA biosynthesis enzymes into a CoA antimetabolite, proposed to inhibit downstream CoA-dependent pathways. However, its precise target remains unknown. Whole-genome sequencing of in vitro-generated AH-2-45-resistant P. falciparum revealed a missense mutation in the gene encoding the endoplasmic reticulum-resident glycerol-3-phosphate 1-O-acyltransferase (PfGPAT), an essential CoA-dependent enzyme involved in phospholipid biosynthesis. We are currently genetically validating PfGPAT as the AH-2-45 resistance determinant and characterising the functional impact of the resistance-associated mutation using PfGPAT activity assays. Elucidating this mechanism may establish PfGPAT as a novel antimalarial drug target and guide structural optimisations of the AH-2-45 antimetabolite and related PanAm mimics.

WM382 is an inhibitor for Plasmepsin IX and X in Plasmodium spp blood and liver stages. These proteases are essential and ubiquitous in Plasmodium spp., where they process diverse proteins involved in egress and invasion of host cells. This makes them ideal targets for drug intervention. Plasmepsin IX and X are also expressed in sporozoites. To decipher their role in this stage, WM382 was administered to mosquitoes after Plasmodium falciparum infection. The number of developing oocysts was the same irrespective of WM382 treatment, though a modest increase in size was detected following drug administration, suggesting differential parasite development. Furthermore, the number of salivary gland sporozoites was dramatically reduced when mosquitoes were treated with WM382. This phenotype points to a defect in egress of P. falciparum sporozoites from the oocyst. We identified accumulation of unprocessed precursors of the essential protein AMA1 in haemolymph and salivary gland sporozoites when treating with WM382, while processing of CSP remained unaffected. Some WM382-treated sporozoites could still invade salivary glands but they displayed significant loss-of-function phenotypes during cell traversal and infection of human HC04 hepatocytes. These results show a role of plasmepsin IX/X during the mosquito stages, raising the possibility of control interventions during transmission.

Cattle ticks are a burden on global agriculture, with chemical treatments the primary method of control. However, ticks are being selected for resistance to these chemicals. Current tests for chemical resistance are slow and require laboratory facilities, inhibiting testing. In this project, we aim to undertake deep sequencing to define polymorphisms controlling resistance and build a database for monitoring of resistance changes. In preliminary studies, a survey and sampling system has been established to capture cattle ticks from across the infested range. Based on initial collections, resistance has been assessed across ten properties, defining resistance to synthetic pyrethroids (SP), amitraz, fluazuron and macrocyclic lactones. A newly developed rapid test for chemical resistance (RaTexT^TM) was used to define resistance to a synthetic pyrethroid, deltamethrin. Resistance to deltamethrin has been found at 100% of properties regardless of whether this chemical is currently in use. In contrast, fluazuron resistance was found at 40% of properties and only at properties where it is currently in use. Future work will assess the allele frequencies of the known polymorphism driving SP resistance, kdr, to determine the accuracy of rapid testing methods and deep sequencing will be undertaken on resistant and susceptible ticks for each chemical class.

Parasites and their hosts engage in an ‘evolutionary arms race.’ As a parasite evolved tools to infect its host, the host will develop adaptations to evade infection. Microbiomes may also play key roles in the arms race between the two antagonists. We characterised the entire microbiome of parasite-host interactions, using the New Zealand native hairworms Gordius paranensis and Euchordodes nigromaculatus and their cave wētā hosts (Rhaphidophoridae) to investigate host and parasite microbiome overlap. Infected wētā, uninfected wētā, juvenile hairworms, and free-living mature hairworms all have microbiomes including viruses, bacteria, fungi, archaea and protists. We found that parasites harbour their own unique microbial taxa, in addition to microbes shared with infected wētā but not with uninfected wētā. This suggests hairworms do not rely on their host to develop a microbiome. As hairworms progress through their life stages, they exhibit a core microbiome; however, microbial community composition varies significantly across life stages, suggesting the environment has a significant effect on the parasite’s microbiome. Therefore, hairworm microbiomes are dynamic across the life cycle and modulated by the host and environment. The hairworm's diverse microbiome raises the intriguing possibility that its symbiotic microbes contribute to the iconic host manipulation (suicidal water-jumping) associated with hairworms.

Toxoplasma gondii is a zoonotic parasite with a global distribution that can infect a wide range of warm-blooded hosts. This study investigated, for the first time, the seroprevalence and genetic variability of T. gondii in red foxes (Vulpes vulpes) from Victoria, Australia. Animals from both regional Victoria and the metropolitan Melbourne area were sourced from trappers and shooters involved in pest control. Sera were screened for anti-T. gondii IgG antibodies using a modified agglutination test, and tissue samples were tested using a qPCR assay targeting the 529 bp repeated element. qPCR positive samples were genotyped using a five-marker (L358, 5’SAG2, 3’SAG2, c22-8, GRA6) polymerase chain reaction-restriction fragment length polymorphism protocol. Anti-T. gondii antibodies were detected in 38.9% (30/77) of foxes, and parasite DNA was identified in 23.4% (18/77) of animals. Genotyping revealed a predominance of T. gondii clonal Type II whereas two isolates showed new alleles attributable to Type II-like genotypes. These findings suggest that Australian red foxes are frequently exposed to T. gondii and may play an important role as epidemiological sentinels to assess the circulation of T. gondii in the Australian environment, with implications for both wildlife conservation and public health.

Integrating traditional morphology with three-dimensional imaging and genetic data supports robust species hypotheses. The paramphistomoid fauna of Australian macropodids is poorly characterised, with two recognised genera, Gemellicotyle and Macropotrema, each containing a single species. Their conical form hampers morphological study, and no molecular data exists, making them ideal candidates for integrative taxonomy. This study describes Gemellicotyle sp. nov. from the caecum of the western grey kangaroo, Macropus fuliginosus. Whole-mount microscopy, serial histology, and X-ray microcomputed tomography (microCT) were combined to generate 3D reconstructions and printed models, enabling characterisation of internal and external morphology. These datasets were integrated with mitochondrial genome and nuclear ribosomal sequence data obtained using long-read sequencing. Gemellicotyle sp. nov. differs from G. wallabicola by lacking a central acetabular protuberance, having simple rather than sinuous caeca, and possessing more extensive vitellaria. MicroCT reconstructions and 3D models revealed 100 acetabular projections composed of radial muscle fibres, and a complex of lymphatic channels surrounding the acetabulum. This integrative approach refines species delineation and uncovers new knowledge on an Australian endemic paramphistome that depend on freshwater snail intermediate hosts to complete its lifecycle. This species may already be extinct due to changes in climate and habitats.

Malaria remains a major global health challenge. Current vaccines RTS,S and R21 targeting the surface circumsporozoite protein provide limited and strain-specific protection, highlighting the need for durable, cross-species protection. Robust T-cell-mediated responses against conserved liver-stage proteins offer strong potential for cross-species protection, but optimal targets are unknown. We have pursued a genome-based, human-informed approach to rational malaria vaccine design by profiling T-cell and antibody reactivity against the complete P. falciparum proteome in malaria-immune individuals. We identified distinct, largely non-overlapping repertoires of T-cell and antibody targets. The most immunodominant T-cell antigens exhibit minimal antibody activity and higher conservation across species, supporting the potential of T-cell targets for cross-species protection. These data support a new paradigm for development of a vaccine to prevent infection and disease.

We prioritized 25 T-cell targets for functional evaluation of immunogenicity and protective capacity in a murine malaria model, using liver-targeted mRNA or DNA-adenovirus platforms. Lead candidates all induced robust liver-resident memory T-cells, with antigen- and platform-specific immune profiles, and conferred protection against P. yoelii sporozoite challenge, reducing both liver- and blood-stage parasitemia. These results validate our genome-based vaccine design, focused on T-cell antigens and provide validated candidates for a next-generation, cross-species malaria vaccine targeting liver stage.

Human hookworm infection, primarily caused by Necator americanus, remains a major global health burden, with vaccine development limited by insufficient identification of protective antigens. This study utilised a proteome microarray of recombinant secreted proteins from adult N. americanus, screened with sera from individuals vaccinated with irradiated third-stage larvae (iL3), to identify immunodominant targets. Selected antigens were characterised and their orthologs identified in the rodent hookworm Nippostrongylus brasiliensis.

Recombinant orthologs were evaluated in a mouse challenge model. One antigen, NBR17057 (ortholog of Na_11335), conferred significant protection, reducing intestinal worm burden and faecal egg output (p < 0.05) and inducing strong antigen-specific IgG responses. These findings support Na_11335 as a promising subunit vaccine candidate targeting the infective larval stage. Additional L3-stage antigens are being investigated to discover an effective novel human vaccine.

Multi-stage, multi-antigen vaccination against malaria is a favoured strategy to improve on the modest efficacy offered by existing vaccines. However, current multi-stage vaccine design neglects the extensive antigenic diversity which exists within populations of Plasmodium falciparum circulating in endemic areas, which has contributed to the low efficacy of multiple single-stage candidates. Using parasite genomes from the MalariaGEN Pf8 release, we combined population genetics with immunoinformatics to assess the potential for vaccine escape of the pre-erythrocytic and blood-stage targets CSP and RH5. We found that the proportion of parasites in sub-Saharan Africa encoding both vaccine-matched alleles for these targets was very low. When we predicted the effects of observed amino acid substitutions on antibody and HLA binding, we found no impact on the RH5 component of the vaccine. However, the majority of parasites sampled had the potential to escape both anti-CSP C-terminal antibodies and vaccine-induced CD4+ T-cell memory responses. We conclude that CSP-based vaccines as components of multi-stage vaccines may not provide the advantage of increased efficacy due to pre-existing polymorphisms in the C-terminal of CSP.

Introduction: Malaria remains a significant health problem. Globally, 282 million malaria cases and 610,000 malaria deaths occurred in 2024. The WHO recommends RTS,S/AS01 and R21-Matrix-M pre-erythrocytic vaccines to prevent malaria in children <5 yrs in moderate-to-high transmission settings. These vaccines are only partially effective. Evidence suggests that pre-erythrocytic vaccines are not boosted by natural malaria infection. We therefore assessed whether a whole-parasite blood-stage vaccine is more efficient in the presence of a malaria infection.

Methods: Different groups of mice received a controlled malaria infection with P. yoelii before or after vaccination. Mice were vaccinated with three doses of either killed 10⁵, 10⁶ or 10⁷ P. yoelii pRBCs formulated with the liposomal adjuvant, CAF01. Four weeks after the final vaccine dose or controlled malaria infection, mice from each group were challenged with homologous parasites.

Results: A priming malaria infection did not provide additional protection against parasitaemia to mice that received 10⁷ or 10⁶ P. yoelii pRBCs in the vaccine; however, it provided additional protection to those vaccinated with a lower dose. Boosting vaccination with malaria infection enhanced control of parasitaemia in all vaccinated groups. Reducing parasite vaccine doses in the presence of infection would lower the cost of vaccinating populations.

The genus Amblyomma is a monophyletic lineage of hard ticks, many species of which parasitize reptiles. The last taxonomic revision of the Amblyomma of Australia was by the great Bob Roberts of Brisbane in 1970. That revision relied solely on morphology. I will present the first molecular phylogenetic tree of the Amblyomma of Australia, with emphasis on the subgenus Cernyomma. My phylogenetic analyses revealed some cryptic species and new host-associations. Additionally, I will present a new diagnostic key of them.

Australia is home to a diverse array of invasive mammals, including pigs, deer, cats, foxes, and rabbits. Although these five species have been reported as hosts to protozoan parasites of the family Sarcocystidae in their native ranges, there has been little investigation into the parasite load of these invasive species in Australia. This study aims to fill in some of this gap by studying species from 3 genera within the Sarcocystidae in selected invasive mammalian hosts. Tissues were collected through opportunistic sampling of deceased invasive mammal species around south-eastern Australia and underwent molecular analysis through PCR and DNA sequencing. This has resulted in species from the genera Toxoplasma and Sarcocystis being identified in invasive mammals. From these identifications a better understanding of the indirect impact invasive animal hosts may be having on an environment through the transmission of parasites through ecosystems, can be drawn. This includes possible spillover into native wildlife hosts which may affect efforts for conservation and relocations. As well as this, spillover into domestic hosts, such as in farming, can affect yields, profits, and risk human health, or represent a risk to household pets.

The eastern paralysis tick, Ixodes holocyclus, causes potentially fatal toxin-mediated paralysis in susceptible domestic animals, livestock, and humans, often requiring urgent medical or veterinary intervention. Yet bandicoots are major natural hosts and appear comparatively tolerant of tick infestation. The mechanism underlying this host difference remains unresolved. This project investigates whether adaptive humoral immunity may contribute to bandicoot protection against the eastern paralysis tick. We are using a comparative omics approach to identify and annotate immunoglobulin-related sequences in Queensland bandicoots, focusing on Isoodon macrourus and Perameles nasuta, with Perameles gunnii included as a closely related reference species. Publicly available bandicoot expressed sequence tags, and the available P. nasuta transcriptome are being analyzed alongside collaborator-supplied P. gunnii genomic data and marsupial immunoglobulin datasets using homology-based annotation. Blood-derived samples from tick-infested I. macrourus and P. nasuta have also been submitted for whole-genome sequencing by Pacific Biosciences high-fidelity long-read sequencing and Hi-C scaffolding to improve recovery of immune loci, including antibody regions. Peripheral blood RNA sequencing will further support identification of expressed immunoglobulin transcripts. Annotated candidate sequences will guide degenerate primer design for future amplification of bandicoot antibody regions and test whether humoral immune responses contribute to natural tolerance of I. holocyclus.

Opportunistic sampling provides a valuable avenue for understanding the health and disease status of wildlife that are otherwise difficult to study. We report findings from a necropsy conducted on a road-killed Malleefowl (Leipoa ocellata) collected in the Fitz-Stirling region of Western Australia during a broader dietary ecology project. Although the original study did not target disease, the carcass presented a rare opportunity to conduct to investigate both ectoparasite and endoparasite communities in this cryptic and nationally vulnerable species. Few parasitological studies have been conducted on this vulnerable species and those that exist are dated. With increasing human encroachment into wildlife habitats and the spread of invasive species, understanding parasite loads and associated risks is becoming increasingly important. This is particularly relevant for Malleefowl, whose ground dwelling and mound building behaviours may increase exposure to soil dwelling parasites, and whose declining populations mean biological samples are rarely available. As many native species face pressure from habitat loss and fragmentation, climate change, and emerging diseases, integrating opportunistic necropsies into ecological and conservation programs can substantially enhance surveillance capacity. This case study underscores the importance of maximising information gained from unexpected wildlife encounters, including road‑kill specimens, to better inform management and conservation strategies.

Parasitism poses significant health challenges for the endangered Australian sea lion (Neophoca cinerea). Australian sea lion pups experience a high prevalence of the endemic hookworm (Uncinaria sanguinis) which is associated with reduced pup body condition and increased mortality. We examined faecal DNA from Australian sea lion pups (n = 63) to further explore host parasite interactions with an emphasis on apicomplexan parasitism. Screening of samples using an Apicomplexan genera PCR targeting the 18S rDNA gene resulted in 51 of the 63 DNA positive samples. DNA sequencing revealed a single parsasite sequence with high similarity between samples from Australian sea lion pups (99.9%) across 900 basepairs. A BlastN Seach identified the sequence from Australian sea lion pups to be 99.7% similar to Neopsora caninum. This first report of N. caninum in Australian sea lion pups demonstrates the environmental continuum that connects parasites associated with terrestrial animals to marine wildlife, and the significance of One Health for wild marine species. Understanding of the impact of N. caninum, and the significance of co-infection with hookworm, for pup health is important for Autstralian sea lion conservation and future management of this endangered marine mammal.

Nasal mites of the family Halarachnidae are common parasites of pinnipeds, although rarely reported in walruses. Two captive walruses at the Ocean Park Aquarium, Hong Kong, were found to be infected with nasal mites identified as Orthohalarachne attenuata (Banks, 1910). Long-term, low-dose ivermectin treatment for heartworm prevention (0.01 mg/kg) had no effect on parasite burden. In contrast, anti-parasitic doses of ivermectin (0.2mg/kg), administered repeatedly over a short-term period (4 doses, 2 weeks apart, followed by 3 doses administered monthly), appeared to successfully clear the parasitic infection, with no signs of re-infection observed for over 12 months post-treatment.

Giardia duodenalis is a parasitic protist and the causative agent of giardiasis, a diarrhoeal disease that infects approximately one billion people annually and results in over 300 million cases of acute or chronic illness. Clinical presentations range from self-limiting disease to persistent and debilitating symptoms. Current treatment relies on a limited number of drugs from few chemical classes, many of which suffer from significant drawbacks, including prolonged treatment regimens, variable efficacy, severe side effects, and reduced effectiveness due to emerging drug resistance. To address these limitations, our team has developed a series of novel antiparasitic compounds, including lead candidates with substantially improved efficacy and selectivity compared with existing therapies.

While the mode of action of these compounds remains unclear, untargeted proteomic and drug‑combination studies suggest that they may act on the parasite cytoskeleton or phosphorylation‑based signalling machinery via previously unexplored mechanisms. These findings, along with ongoing efforts to define the mode of action of this compound series, will be discussed.

Malaria caused by Plasmodium falciparum remains a major global health challenge, with increasing resistance to frontline treatments highlighting an urgent need for new antimalarial therapies. The coenzyme A (CoA) biosynthesis pathway of P. falciparum represents a promising antimalarial drug target. Phosphopantothenoylcysteine synthetase (PPCS), the second enzyme in the pathway, is of particular interest due to its role as a flux-control step. To identify inhibitors of PfPPCS, we have screened ~50 compounds initially designed to inhibit the bacterial PPCS. RCS-33 and HDS-44 emerged as promising candidates, with antiplasmodial IC₅₀ values of ~1 µM. Although the activity of the compounds can be somewhat modulated by overexpression of PfPPCS, consistent with them being on target, their mechanism of action remains to be confirmed. We are currently generating RCS-33- and HDS-44-resistant parasites to try and identify the target via whole-genome sequencing of resistant parasites. We will also use an enzyme assay and purified PfPPCS to test directly whether the compounds are able to inhibit PfPPCS activity.

Malaria remains a leading cause of morbidity and mortality, with 608,000 deaths reported in 2022, predominantly among children under five in sub-Saharan Africa. The disease, predominantly caused by Plasmodium falciparum, faces escalating challenges due to the emergence of strains resistant to all frontline antimalarials, including artemisinins. This highlights an urgent need for new therapeutic strategies. While de novo drug discovery is slow and costly, repurposing existing compounds offers a rapid and cost-effective alternative.
We screened the Structural Genomics Consortium’s Donated Chemical Probes Library, which consists of compounds originally developed for human diseases, to identify candidates with antimalarial potential. From 200 compounds, 11 demonstrated sub-micromolar potency against the P. falciparum Pf3D7 reference strain and retained activity across five resistant lines. Their equipotent profiles suggest novel mechanisms of action distinct from existing drug classes. In vitro pulse activity assays further characterized compound speed-of-action and asexual stage-specific antimalarial activity.
Future work will employ unbiased multi-omics approaches, including as untargeted metabolomics, solvent proteome profiling and limited-proteolysis mass spectrometry, to elucidate molecular targets and validate these candidates as starting points for drug development. These findings highlight the potential of compound repurposing to accelerate antimalarial discovery and identify new druggable pathways to combat resistance.

The rapid emergence of drug‑resistant Plasmodium falciparum necessitates novel antimalarial strategies. Because parasite survival relies on extensive modification of host erythrocytes, host‑directed therapies represent an attractive approach. Here, we evaluated a panel of anticancer kinase inhibitors as potential antimalarials, initially hypothesising that they act through inhibition of host signalling pathways. We focused on the proposed requirement for activation of the human MAPK pathway in infected erythrocytes for parasite proliferation. The MAPK pathway tightly regulates cellular proliferation and survival, and its dysregulation in cancer has driven the development of numerous selective kinase inhibitors. Several compounds, displayed submicromolar potency against both asexual erythrocytic‑stage parasites and sexual gametocytes, indicating potential for dual curative and transmission‑blocking efficacy. However, detailed mechanistic studies of MEK1 inhibitors provided little evidence for host‑directed activity. Overexpression of human MEK1 in infected erythrocytes did not alter drug potency, parasites exposed continuously to one MEK1 inhibitor rapidly evolved resistance, and another inhibitor exhibited marked strain‑dependent activity across P. falciparum isolates. These observations support a parasite‑directed mode of action. Collectively, our findings demonstrate that human MEK1 is not essential for parasite proliferation. Despite host toxicity, parasite‑selective activity provides a platform for designing kinase inhibitor derivatives.

Gastrointestinal parasitism and inappropriate anthelmintic use are major constraints to goat production and key drivers of anthelmintic resistance (AR), particularly in low- and middle-income countries. This study evaluated parasite control practices recommended by veterinarians to goat farmers in Sri Lanka to identify critical gaps contributing to AR. An online questionnaire was distributed to 877 veterinarians following a pilot survey, and 122 completed responses (14%) were analysed. Data were collected on respondent demographics, knowledge of gastrointestinal helminths, diagnostic and control practices, anthelmintic use and AR awareness. Although respondents demonstrated sound knowledge (median confidence score: 70; mean: 65), diagnostic approaches relied on clinical signs (35%) and visual observation of worms in faeces (22%), with limited use of faecal egg counts (FEC). Limited diagnostic access (39%) and low farmer engagement (36%) were key barriers to recommending FEC. Albendazole, levamisole, and ivermectin were widely recommended; however, 41% of veterinarians estimated doses visually, increasing under-dosing risk. While 92% recognised AR as a major concern, 71% had never performed faecal egg count reduction tests. Multiple correspondence analysis identified distinct clusters of practices, separating experience-based from evidence-based approaches. These findings highlight critical gaps and the need for improved diagnostics, targeted training, farmer engagement, and national AR surveillance.

Malaria remains a major global health challenge, with substantial morbidity and mortality despite ongoing control efforts. Current vaccines targeting the pre-erythrocytic stage provide only partial and waning protection, highlighting the need for improved strategies. One promising approach is the development of multi-stage vaccines that target different stages of the parasite lifecycle to enhance overall efficacy and durability. Virus-like particles (VLPs) provide an attractive platform for vaccine design due to their ability to present antigens in a highly repetitive and ordered manner, thereby promoting robust immune responses. Increasing evidence suggests that the density of antigens on nanoparticle platforms plays a critical role in shaping immunogenicity. In this study, we explored engineering approaches to optimise antigen display on VLPs and systematically modulate antigen density. We demonstrate that engineered VLPs can maintain structural integrity while accommodating varying levels of antigen presentation. Importantly, increasing antigen density was associated with enhanced antibody responses, supporting the concept that antigen valency is a key determinant of immunogenicity. These findings provide a foundation for the rational design of next-generation nanoparticle vaccines including multi-stage/multi-antigen designs that are currently in progress in our lab.

Malaria remains a major global health challenge due to the complexity of the Plasmodium life cycle, the partial efficacy of current vaccines, and disease severity driven by both parasite factors and host immune responses, including perforin-mediated cytotoxicity. We investigated the impact of treatment timing with a perforin inhibitory compound on disease progression in vaccinated and unvaccinated mice infected with Plasmodium yoelii. Vaccinated mice received killed, whole P. yoelii blood-stage parasites formulated with liposomes and the TLR4 agonist 3D-(6-acyl)-PHAD. Mice were challenged with 10⁵ P. yoelii parasitised red blood cells and treated with a perforin inhibitory compound or vehicle control using two regimens: early (days -1 to 3 post-infection) or late (days 4 to 8 post-infection). Mice were monitored over 26 days. Early perforin inhibitory treatment showed a trend towards reduced parasitaemia and clinical severity; however, these changes were not statistically significant compared with the control groups in either vaccinated or unvaccinated mice. Notably, unvaccinated mice treated with the perforin inhibitory compound exhibited a 6–8 day extension in survival compared to controls, regardless of early or late treatment, although all mice ultimately succumbed to infection. These findings suggest perforin-mediated cytotoxicity contributes to malaria pathology and may be a therapeutic target.

Scabies is a common, debilitating neglected tropical disease that disproportionately affects overcrowded and resource-limited populations worldwide. Beyond the primary infestation, secondary bacterial infections can lead to severe complications, including sepsis, glomerulonephritis, and rheumatic fever and heart disease, contributing to significant morbidity and mortality. Early and accurate diagnosis is therefore critical for effective disease control.

Historically, scabies diagnosis has relied on the direct visualisation of mites, with microscopic examination of skin scrapings remaining the most widely used confirmatory method. More recently, non-invasive imaging techniques such as dermatoscopy, videomicroscopy, and reflectance confocal microscopy have improved diagnostic capability; however, their accessibility remains limited. To date, no molecular or serological diagnostic test has been successfully translated into routine clinical use. PCR- and ELISA-based approaches have shown promise but are constrained by their reliance on specialised equipment, cost, processing time, and technical expertise. While the International Alliance for the Control of Scabies has introduced standardised diagnostic criteria, a major gap persists in the availability of practical, point-of-care tools for near-patient diagnosis.

To address this unmet need, our work focuses on developing next-generation point-of-care diagnostics for scabies. Using proteomic approaches, we have identified highly abundant, scabies-specific faecal proteins as novel antigenic biomarkers. Our translational pipeline includes recombinant antigen production, monoclonal antibody and nanobody generation, and the development of ELISA- and lateral flow assays targeting both mite-derived proteins and host immune responses. These platforms are being validated through preclinical studies in a porcine scabies model and multicentre clinical trials in collaboration with industry and international partners.

Almost all cells have a shape, size, and organisation specialised for their functions. During replication, malaria parasites are amorphous and disorganised. By contrast, their host-cell-invading ‘zoite’ stages exhibit extreme apical-basal polarity, with invasion-specialised organelles at their apical end. It is currently unclear when this transition begins, how it is initiated, or what proteins control it.

Using ultrastructure-expansion microscopy, we imaged blood-stage, liver-stage, and mosquito-stage malaria parasites from replication until the completion of zoite formation to identify how this disorganised to hyper-polarised transition occurs. In all three lifecycle stages, the first sign of polarity establishment in the parasite was the anchoring of a structure called the centriolar plaque to the parasite plasma membrane. Subsequently, the parasite would begin to build its invasion-specialised organelles at this site, suggesting that this anchoring event represents the establishment of apical-basal polarity. In blood-stage parasites we observed a dramatic repositioning of the Golgi following centriolar plaque anchoring, providing a potential mechanism for how this event triggers apical organelle biogenesis. Work is currently ongoing to define the centriolar plaque proteins that coordinate the establishment of polarity within the parasite. Collectively, this study provides new insights into the biology of daughter cell formation in malaria parasites.

Malaria parasites depend on the apicoplast, an intriguing organelle of algal origin, for survival throughout the life cycle. Transport of metabolites across the apicoplast membranes is poorly understood, and only 11 transporter proteins have been confirmed to localize to the organelle to date. We report apicoplast localization of two previously uncharacterized transporters in Plasmodium falciparum. Knockdown of apicoplast transporter 1 (at1) resulted in death of asexual blood-stage parasites. Knockout of at1 in PfMev parasites, which have a metabolic apicoplast bypass, resulted in disruption of apicoplast morphology and loss of the organellar genome, suggesting that AT1 is involved in apicoplast housekeeping. Knockout of apicoplast transporter 2 (at2) did not affect asexual blood-stage parasites, nor gametocyte and gamete formation. In the mosquito, however, oocyst size was significantly decreased and no sporozoites were observed in salivary glands up until day 21, phenocopying knockouts of fatty acid metabolism. Metabolomics, drug assays, transport assays in yeast, and protein modeling provided further information on candidate substrates for both transporters. Taken together, we identified two novel apicoplast transporters, with AT1 being essential for asexual blood stages by supporting apicoplast housekeeping, and AT2 being important for parasite growth in mosquitoes, possibly by facilitating fatty acid metabolism.

Type IV P-type ATPases (P4-ATPases) are critical regulators of membrane lipid asymmetry in eukaryotic cells. Plasmodium falciparum is predicted to encode six P4-ATPases, but their roles remain to be defined. Recently, amplification of the gene encoding one of these, PfATP2, was associated with resistance to the antiplasmodial compounds MMV007224 and MMV665794. Here, we show that PfATP2 is a plasma membrane localised P4-ATPase that functions as a phospholipid flippase and is important for parasite growth. Using genetically modified parasites, we found that the PfATP2 expression level of parasites correlates with the rate by which they internalise a fluorescent analogue of phosphatidylserine (NBD-PS). Overexpression of PfATP2 enhanced NBD-PS translocation, whereas conditional knockdown significantly impaired this process. Further, exposure of parasites to MMV007224 and MMV665794 gave rise to a reduction in NBD-PS internalisation. PfATP2 knockdown parasites were hypersensitive to growth inhibition by MMV007224 and MMV665794, while PfATP2 overexpressing parasites were resistant to the compounds. Taken together, these findings establish PfATP2 as a major contributor to ATP-dependent phosphatidylserine internalisation on the parasite plasma membrane and a potential target of MMV007224 and MMV665794. We are currently investigating whether a reduction in PfATP2-mediated phospholipid flipping affects the activities of other transporters on the parasite plasma membrane.

Despite global gains combating malaria, the increasing incidence of antimalarial drug resistance to front line therapeutics demands new drugs with novel targets be developed. Potential targets for the design of therapeutic drugs include channel proteins that are critical for the movement of essential cargo within the parasite. Here, the essentiality of the voltage dependent anion channel (VDAC) was investigated in the deadliest species of malaria P. falciparum, via protein knockdown and localisation studies, followed by mitochondrial drug sensitivity studies and metabolomic analysis. Knockdown of vdac led to a survival defect in the RBC stages. Furthermore, the failure to generate conventional knockouts indicated VDAC is essential for parasite survival. Immunofluorescent microscopy successfully localised VDAC to the mitochondria, while the knockdown of VDAC was shown to sensitise parasites to mitochondrial target drugs atovaquone and proguanil, providing further indication for a role at the parasite mitochondria. Analysis of the parasite metabolic profile following VDAC knockdown is currently being used to investigate a possible role in the pyrimidine biosynthesis pathway at the outer mitochondrial membrane. Whilst the precise role of VDAC at the mitochondria requires further investigation, this channel protein is an essential and unique target for the future design of novel antimalarial therapeutics.

Pfs16 is a 16 kDa protein expressed early in the process of gametocyte development in Plasmodium falciparum. It localises to the parasitophorous vacuole membrane (PVM) of gametocytes. Previous studies have focused exclusively on its monomeric form. However, AlphaFold modelling predicts that Pfs16 assembles into an oligomeric complex containing a membrane-spanning pore. Given the essential role of Pfs16 in parasite transmission, we aimed to characterise this oligomeric structure and its function, which could provide new insights for transmission-blocking strategies. A combination of molecular and structural biology techniques was employed, including chemical crosslinking, Western blotting, native gel electrophoresis, and surface biotinylation, to explore its oligomeric subunits. Its functional activity was characterised using electrophysiological analysis in the Xenopus oocyte expression system. Both in silico modelling and experimental data indicate that Pfs16 forms a pentameric complex. Electrophysiological analysis in Xenopus oocytes has demonstrated that the membrane-spanning pore exhibits ion-conducting activity, supporting the presence of a functional pore. These results provide evidence that Pfs16 assembles into an oligomeric, likely pentameric, ion channel. Given its essential role in gametocyte development and transmission, targeting this complex may represent a promising strategy for the development of transmission-blocking interventions.

The intracellular apicomplexan parasite Toxoplasma gondii relies on both nutrient scavenging and biosynthetic pathways to acquire amino acids required for growth and survival. Our previous work identified the plasma membrane transporter TgApiAT2 as the primary glutamine transporter and, through a CRISPR-based screen, revealed that multiple amino acid biosynthetic pathways become fitness-conferring upon TgApiAT2 disruption, suggesting functional redundancy between uptake and synthesis. Here, we experimentally validate this model by generating double mutants lacking TgApiAT2 alongside key enzymes in amino acid biosynthesis. These mutants exhibit severe growth defects, demonstrating that parasites depend on compensatory mechanisms to maintain amino acid homeostasis. To further characterise TgApiAT2 function, we performed radiolabeled uptake assays, confirming that TgApiAT2 mediates the uptake of numerous non-essential amino acids. Together, our findings provide direct functional evidence for redundancy between amino acid uptake and synthesis in T. gondii, highlighting the metabolic flexibility that underpins parasite adaptation to variable host nutrient environments.

Background and Aims

Fasciola hepatica is a globally distributed helminth of importance to both human and animal health. Critical information on how F. hepatica interacts with its mammalian host is lacking due to a reliance on animal models. This study aimed to validate a recently-developed HepG2-derived 3D spheroid co-culture model for F. hepatica newly excysted juveniles (NEJ) against in-vivo infection, using advanced microscopy methods.

Methods

In-vivo samples from C57BL/6 mice, infected with 175 metacercariae each, and NEJ grown in-vitro were collected at 12, 48, 120, 144, 168, 180, and 192 hours post infection. Comparison of the growth and development of external morphological (spines, sensory papillae, suckers) and internal anatomical (musculature, gut and uterine development) features between the two culture conditions were made using fluorescent confocal and scanning electron microscopy.

Results

The data obtained provides the first detailed morphological comparison of the growth and development of F. hepatica NEJ cultured in-vitro and in-vivo and serves as a benchmark to enhance future models.

Conclusion

The progression of animal-free models will enable exploration of the intricacies of early infection. Future work will incorporate spatial transcriptomic analysis to elucidate temporal shifts in F. hepatica development and the subsequent discovery of drug and vaccine targets.

Fasciola hepatica causes fasciolosis in livestock and humans worldwide, yet reliable tools to assess drug efficacy against the early developmental stages of this parasite are lacking. Here, we developed an automated miracidial motility assay (MMA) using the WMicroTracker ONE infrared detection system to quantify the sensitivity of F. hepatica miracidia to anthelmintic compounds including clorsulon (CLORS), closantel (CLOS), triclabendazole (TCBZ) and triclabendazole-sulphoxide (TCBZ-SO). Systematic optimisation of assay conditions, including inoculum size, observation window and solvent concentration yielded a reliable platform for evaluating the sensitivity of F. hepatica miracidia from diverse geographic isolates to these compounds. Our results demonstrated that three compounds (CLOS, TCBZ and TCBZ-SO) produced concentration-dependent motility inhibition, whereas CLORS had no effect. CLOS displayed the highest potency among isolates from New South Wales (NSW), Tasmania (TAS) and Victoria (VIC), whereas TCBZ and TCBZ-SO exhibited isolate-specific sensitivity patterns. Miracidial responses of the NSW and TAS isolates to TCBZ, TCBZ-SO and CLOS were also compared in vitro with those of newly excysted juveniles (NEJs) produced from the same isolates. Overall, the findings show that MMA provides a reproducible, host-independent and high-throughput phenotypic platform for assessing miracidial sensitivity to compounds.

Fasciolosis, caused by the liver fluke Fasciola hepatica, is a climate-sensitive parasitic disease that threatens livestock productivity and farm profitability, with broader implications for food security, rural livelihoods, and sustainable food systems. This study aimed to quantify historical trends and project future fasciolosis risk across Victoria under changing climate conditions. High-resolution (5 km²) climate data were retrieved for 40,504 grid points across Victoria to validate a Growing Degree Days (GDD) model for estimating fasciolosis risk over the past 50 years (1975–2024) and to project future risk centred at 2050 and 2090 under medium (RCP 4.5) and high (RCP 8.5) representative concentration pathways. Linear regression analysis demonstrated a strong relationship between observed fasciolosis prevalence and modelled risk values (R² = 0.94, p < 0.003). Historical analyses revealed substantial interannual variability, with consistently higher risk in eastern Victoria, followed by western and northern regions. Under future climate scenarios, risk increased spatially by up to two-fold in Barwon and three-fold in the Great South Coast, particularly under the 2090 RCP 8.5 scenario. These findings provide spatially explicit evidence to support climate-responsive surveillance, risk-based control strategies, and integrated animal health and environmental policy development.

Gastrointestinal nematodes impose economic burdens on the sheep industry, impacting on animal welfare and management costs. Species surveillance is essential, yet larval culture is inefficient for large‑scale monitoring. Nemabiome deep-amplicon sequencing allows for sensitive detection of nematode species directly from eggs without having to hatch eggs for 10-14 days like larval culture.

This study compared larval culture with nemabiome sequencing to speciate worms from bulk faecal samples from 27 farms. Spearman’s correlations showed significant positive correlations for Haemonchus contortus (r_s=0.56, p<0.01), and Teladorsagia circumcincta (r_s=0.58, p <0.01) and a moderate positive correlation for Trichostrongylus spp (r_s=0.34, p=0.07). Positive correlations between the two techniques provides some confidence that nemabiome sequencing is useful for large-scale surveillance of nematode species across Victoria, which is being completed on saleyard samples collected four times a year for a two-year period.

Initial findings on 100 samples show that Victoria’s most abundant species are Teladorsagia circumcincta (92%), Trichostrongylus vitrinus (78%) and Haemonchus contortus (54%). Given the high prevalence and pathogenicity of T. vitrinus compared to other Trichostrongylus species more research should focus on understanding this worm to enhance management strategies. Less common species included Trichostrongylus colubriformis, Chabertia ovina, Trichostrongylus axei, Oesophagostomum venulosum, Nematodirus spathiger and Trichurus ovis.

Increased drench resistance in sheep parasite populations necessitates alternative control measures. Unlike Barbervax, no vaccines exist for sheep scour worms. Detailed knowledge of protective immunity is essential for vaccine development designed to mimic natural host responses. In this study, 17-week-old parasite-naïve Merino lambs were exposed to weekly trickle infections of 6,000 infective Trichostrongylus colubriformis larvae for 16 weeks; controls remained parasite-free. After 16 weeks, mean faecal egg counts were 1518 and 0. Histologically, there was a time-dependent increase in intestinal goblet cells and decrease in jejunal mast cells in infected lambs. Flow cytometry at week 16 identified Ki67⁺GATA3⁺CD4⁺ T cells, indicating Th2 polarisation and expansion, with increased plasma and mucus anti-larval IgA and IgG. After drenching and challenge with 10,000 larvae, trickle-infected lambs rejected ~83% of larvae and had significantly lower worm burdens than controls. Anti-L3 T. colubriformis secretory IgA and IgG in bile may indicate portal immunoglobulin recycling from the gut. Additionally, in vitro antigen re-stimulation of cryopreserved intestinal cells showed increased Ki67⁺GATA3⁺CD4⁺ proliferating leukocytes with soluble L3 antigens. These results indicate 16 weeks of exposure creates a hostile intestinal environment for L3 establishment. Ongoing work assesses responses to L3/L4 antigens and associated ovine intestinal gene expression profiles.

Phenotypic screening readily identifies compounds that impair worm motility or development, the intrinsic biological processes underlying chemical sensitivity in parasitic nematodes remain poorly defined. Here, we identified a hit compound with a pyridyl scaffold from a phenotypic screen against the parasitic nematode, Haemonchus contortus, and using structure–activity optimisation we generated a potent chemical probe, WEHI-864. To uncover protein networks associated with the mechanism of action, thermal proteome profiling and time-resolved quantitative proteomics interrogated WEHI-864-induced perturbations in H. contortus. Across larval and adult stages of this major parasite of livestock, proteome integral solubility alteration (PISA) assay revealed reproducible alterations in proteins associated with cytoskeletal organisation and intracellular trafficking, including actin- and motor-related components. Complementary quantitative proteomics identified induction of an aspartyl protease and suppression of secretory CAP family proteins. Integrated analysis of these datasets supports a model in which chemical perturbation of cytoskeletal and trafficking proteins is associated with secondary modulation of proteolytic pathways, coinciding with rapid impairment of motility. These findings indicate that linked structural and proteolytic responses contribute to chemical sensitivity in H. contortus and demonstrate how integrative proteomics can resolve organism-level responses to chemical perturbation beyond single-target paradigms.

Background and Aims: Scabies is a neglected tropical skin disease affecting over 400 million people annually, causing a significant public health burden particularly among resource limited regions worldwide. Mite infection alters the skin microbiome and often leads to secondary bacterial skin infections and further serious sequelae. This study investigates whether scabicide therapy fully eliminates pathogens and restores the skin microbiome at the sites of scabies lesion.

Methods: Full-length 16S rRNA sequencing on PacBio platform was performed for 1224 skin scrapings samples collected from scabies lesions and their corresponding uninfected control sites. Participants received a prescribed scabies treatment, i.e. permethrin, ivermectin or a combination of permethrin and ivermectin. Samples were collected at three time points: before treatment, 5–7 days after the initial visit, and 4–6 weeks after the initial visit.

Results: Sequencing identified 114,403 Amplicon sequence variants across 1224 samples and 52 kit controls. Preliminary analysis indicates that the treatments restore bacterial diversity and reduce bacterial pathogen abundance in the healed sites, though the efficiency of pathogen reduction varied between young children and adults.

Conclusions: Early results show the complex interactions between scabies treatment, skin microbiome and host factors such as age with implications for managing secondary infections.

Kissing bugs are known to produce anticoagulant venom that facilitates blood-feeding. However, it is unknown how this saliva evolved and if the venom produced by the entomophagous ancestors of kissing bugs would have helped or hindered the trophic shift. In this study, we show that venoms produced by extant predatory assassin bugs have strong anticoagulant properties mediated chiefly by proteolytic degradation of fibrinogen, and additionally contain anticoagulant disulfide-rich peptides. However, venom produced by predatory species also has pain-inducing and membrane-permeabilizing activities that would be maladaptive for blood-feeding, and which venom of the blood-feeding species lack. This study demonstrates that venom produced by the predatory ancestors of kissing bugs was exapted for the trophic switch to blood-feeding by virtue of its anticoagulant properties. Further adaptation to blood-feeding occurred by downregulation of venom toxins with proteolytic, cytolytic, and pain-inducing activities, and upregulation and neofunctionalization of toxins with anticoagulant activityindependent of proteolysis.

Scabies is a neglected tropical disease affecting approximately 400 million people globally. The obligate lifecycle of Sarcoptes scabiei has limited our understanding of its biology, largely due to difficulties in maintaining the parasite outside its host. The development of an ex-vivo culture system has facilitated improved investigation of the mite’s complex biology. With the known prevalence of symbionts amongst haematophagous arthropods and the strong association with secondary bacterial infections, this study has attempted to provide the first life-stage specific microbiota and to identify core components of the S. scabiei microbiota. Over 48,000 individual parasites were collected across five key life-stages (eggs, larvae, nymphs, males and females). 16S full-length rRNA amplicon sequencing was performed on the PacBio platform. A total of 3,500,187 reads and 487 amplicon sequence variants (ASVs) were identified. The genera Corynebacterium, Serratia and Acinetobacter were present across all life-stages with the opportunistic pathogens Acinetobacter baumannii and Serratia marcescens identified as key constituents of the scabies microbiome. This study provides the first evidence of a stable core microbiota across all life stages of S. scabiei, offering new insights that could improve understanding of mite biology and management of scabies and associated secondary bacterial infections.

Scabies, caused by Sarcoptes scabiei, is a highly prevalent skin disease characterised by severe and persistent pruritus manifesting in over 90% of patients. The limited effectiveness of antihistamines suggests a dominant role for non-histaminergic itch pathways, yet the underlying mechanisms remain poorly defined.Using a porcine scabies model, we localised itch mediators, such as PAR-2, MRGPRX2, tryptase, histamine, IL-31, periostin, NK-1R, β tubulin III and substance P, during infection using immune-histochemistry. Significant upregulation of PAR-2, MRGPRX2, tryptase, histamine, IL-31, periostin, NK-1R and substance P was observed following infection, while β tubulin III expression was reduced. Building on these findings, we aim to investigate keratinocyte-associated receptors (PAR-1, PAR-2, and MRGPRX2) in mediating itch responses to mite stimuli. HaCaT keratinocytes will be treated with whole mite extracts and recombinant proteins (SMIPP-Cc, Sar s 1c), followed by total RNA extraction, cDNA synthesis, and qPCR analysis of target gene expression, normalised to internal control GAPDH expression.These findings support the involvement of both histaminergic and non-histaminergic pathways in scabies itch. The second part of the study is expected to define keratinocyte-specific receptor responses, providing mechanistic insight into non-histaminergic itch signalling and identifying potential therapeutic targets for treatment-resistant and chronic pruritus.

Parasitic worms continue to exert major health and economic burdens on humans and livestock, while escalating resistance to existing anthelmintics highlights the urgent need for novel chemotypes with distinct modes of action to support integrated control strategies. We screened 139,916 compounds from the Medicines for Malaria Venture Hit Generation Library 1 against exsheathed third-stage larvae of Haemonchus contortus, with cross-species assessment in Caenorhabditis elegans. High-throughput infrared-based motility and developmental assays in 384-well format showed robust performance (mean Z′ = 0.799 ± 0.012; signal-to-background = 65.6 ± 9.8). From this screen, 272 primary hits (0.194%) were identified, of which 110 reproducibly inhibited larval motility and development. Among these, 39 compounds exhibited IC₅₀ values <10 µM, and 33 induced complete developmental arrest at ≤12.5 µM, often with distinct morphological phenotypes. Four of the 39 compounds showed no detectable toxicity in HepG2 cells (CC₅₀ and MC₅₀ ≥20 µM), with ADME profiling available for a prioritsed subset. Integrating potency, selectivity and ADME properties enabled prioritisation of 16 compounds for advancement through medicinal chemistry. Collectively, these findings demonstrate that antimalarial-focused libraries can yield potent and selective nematocidal scaffolds, and highlight a scalable strategy for repurposing discovery libraries across various parasitic systems.

Gastrointestinal nematodes (GINs) are a major constraint to goat health, welfare and productivity worldwide and represent the highest-priority pathogens affecting goats in Australia. However, contemporary national-scale epidemiological data for Australian dairy goats are limited. This study quantified the prevalence, infection intensity, species diversity and determinants for GIN infections in Australian dairy goats. Faecal samples (n = 1,028) collected from 68 herds across Australia were analysed using a modified McMaster technique. Strongylid-positive samples (n = 500) underwent deep amplicon sequencing of the ITS-2 rDNA region for species identification. Prevalence estimates were adjusted for herd-level clustering, and predictors for strongylid faecal egg counts (FECs) were evaluated using linear mixed-effects models. Strongylids were detected in 91% of goats and in all herds, substantially exceeding the prevalence of Trichuris spp. (13%) and Nematodirus spp. (5%). Strongylid FECs were markedly overdispersed, with 30% of animals contributing 80% of total egg output. Age, climatic zone, anthelmintic treatment and coinfection with Eimeria were statistically significant (P < 0.05) determinants of strongylid FECs. Metabarcoding identified 11 species, dominated by Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis, with distinct regional patterns. These findings demonstrate substantial infection pressure and species diversity, informing evidence-based parasite control for the Australian goat industry.

Fasciola hepatica larval development, infection, and presence of intermediate lymnaeid snail hosts require average daily temperatures >10°C. Livestock producers leverage the seasonal pause between the first and last frosts to guide treatment schedules. Whilst conducting a drug resistance trial in July 2024, numerous lymnaeid snails were discovered when average daily temperatures were <7°C, challenging the foundations underpinning these schedules. We set out to update knowledge on the seasonality of lymnaeid snail populations in the region to refine current F. hepatica risk periods and inform new integrated parasite management strategies.

Twelve sites across six farms endemic for F. hepatica were sampled bi-monthly during 2025. Collected snails were counted and morphologically speciated to determine the average abundance and diversity of susceptible hosts. Snails were visually inspected for F. hepatica larval infection, then confirmed with qPCR. One site significantly deviated from the historical seasonal pattern, recording the study’s highest abundance of lymnaeid snails (N = 240) during winter. The invasive Pseudosuccinea columella was most abundant in July at three sites. This study provides the first seasonal monitoring of the invasive P. columella and their increased abundance in winter suggests that the infective risk period for F. hepatica extends beyond the historical dormancy window.

PfCSC1 is a protein found in Plasmodium falciparum that belongs to a family of osmosensitive cation channels, some members of which have been found to double as scramblases (ATP-independent phospholipid transporters). Mutations in PfCSC1 or a putative rhomboid protease (PfROM8) are associated with resistance against specific compounds, termed PfROM8/PfCSC1-linked compounds (R/CLCs). To understand the mode of action of these compounds, the function of PfCSC1 must be understood. Previous research shows that PfCSC1 is an essential ion channel that can be activated by R/CLCs, with Na+ being one of its substrates.

Here, I present evidence that PfCSC1 doubles as a scramblase, capable of phospholipid transport in the parasite plasma membrane. The internalisation of a fluorescent phospholipid analogue (NBD-PS) was measured in ATP-depleted parasites under several conditions. Knockdown of PfCSC1 did not have a significant effect on NBD-PS internalisation. However, upon exposure to hypotonic conditions or R/CLCs – both predicted to activate PfCSC1 – parasites expressing a normal level of PfCSC1 displayed a significant increase in NBD-PS internalisation, whereas the response of parasites in which PfCSC1 was knocked down was less pronounced. The data suggest that while PfCSC1 is capable of phospholipid scrambling, it is likely not always active under physiological conditions.

The formation of the nucleus is one of the most significant paradigm shifts in the evolution of species. The nucleus allows eukaryotes to transcribe with higher fidelity and better regulate the expression of their genes, resulting in highly specialised cells; the caveat being that eukaryotes must transport their RNA cargo into the cytoplasm to re-couple the partitioned transcription and translation. Most eukaryotes use an RanGTP‑dependent system for nucleocytoplasmic transport including for the export of non-coding RNA. In addition, fungi and metazoans have evolved specialised RanGTP-independent pathways to export most Poly‑A+ mRNA.

The mechanisms of mRNA export in protist parasites are relatively understudied. Proteins that have conserved sequences to proteins involved in RanGTP‑independent mRNA export in humans and yeasts have been identified in Plasmodium spp. Toxoplasma gondii, and Cryptosporidium spp based on conserved sequences. However it is unclear if these parasites have mechanisms of mRNA export that are analogous to the RanGTP‑independent metazoan mechanisms or if they have innovated parasite specific mechanisms of mRNA export.

I aim to determine if apicomplexan parasites have evolved parasite specific processes of mRNA export by identifying key molecules involved nucleocytoplasmic transport.

Malaria remains a global health burden and with ongoing resistance across all classes of antimalarials, advancing our understanding of Plasmodium’s biology could help identify novel therapeutic targets. During continuous in vitro culture, mutations commonly arise within the parasite genome, although these are often phenotypically silent. However, we have identified a sorbitol-resistant Pf3D7 strain that no longer undergoes haemolysis when exposed to isotonic concentrations of sorbitol, indicating a disruption in nutrient acquisition via new permeability pathways (NPPs) formed by parasites to facilitate enhanced nutrient uptake. In contrast to other sorbitol-resistant lines, this occurs without growth defects under standard culture conditions. Whole genome sequencing of clonal parasites identified a recombinant CLAG3 gene (CLAG3n) with a missense mutation at the recombination region. CLAG3 is a component of the RhopH complex, a trimeric protein complex essential for NPP formation. To characterise the phenotype of our CLAG3n line, we assessed parasite growth under normal and nutrient-deprived conditions and performed osmotic lysis assays using a range of solutes to evaluate changes in substrate selectivity. Additionally, we conducted proteome-wide analyses to investigate alterations in protein expression and aim to conduct localisation studies to determine the impact of the recombination and mutation on protein export and NPP function.

The invasive tick Haemaphysalis longicornis is an important vector of veterinary and
public health significance and has expanded beyond its native Asian range into Australia,
Western Pacific Islands, and the USA. Despite its growing biosecurity importance, the
global phylogeographic structure of this species remains unknown. This study
investigated the evolutionary relationships and population structure of H.
longicornis using 1,396 cytochrome c oxidase subunit I (COI). Sequences represented
native populations from China, Japan, South Korea, and Russia, and invaded populations
from Australia, New Zealand, Tonga, Pakistan, and the USA. A total of 166 haplotypes
were identified, with high haplotype diversity (Hd = 0.88). Haplotype network and
phylogenetic analyses identified two major lineages: a cosmopolitan lineage shared
between native and invaded regions, and a second lineage restricted to Asia. Population
genetic analyses demonstrated contrasting levels of genetic differentiation within and
among countries, including high differentiation between Korea and the USA (FST =
0.73), while the lowest differentiation occurred between China and Korea (FST = 0.06).
The cosmopolitan lineage displayed a star-like topology, suggesting demographic
expansion and dispersal into invaded regions. These findings provide new insights into
the invasion events, dispersal pathways, and evolutionary structure of H. longicornis.

Ticks pose health risks to humans, companion animals and livestock through pathogen transmission, making knowledge of their seasonal activity vital for monitoring tick-borne disease. No studies have investigated the seasonal presence of questing tick species and life stages in Western Australia. This study presents preliminary findings from an ongoing phenological survey (October 2025 to October 2026) across four Swan Coastal Plain sites encompassing banksia woodland and pastoral land. Thirty-two fortnightly flagging sessions were conducted; flags were dragged and inspected at 10 m intervals with specimens morphologically identified to species and instar. All 1,859 ticks collected were Amblyomma triguttatum: larvae 88.2% (n = 1,639), nymphs 11.4% (n = 211) and adults 0.5% (n = 9). A seasonal shift was observed, with nymphs most prevalent in October to November 2025 and larval activity emerging in January 2026, peaking in February (n = 822). Site-level abundance ranged from 3.04 to 9.52 ticks per 100 m. Comparison with iNaturalist data (n = 227 observations, 2023 to 2025) revealed a spring-biased, adult-dominated reporting pattern, contrasting with flagging results where adults were largely absent and late-summer larval emergence was substantial. These findings highlight the value of combining standardised surveys and citizen science in tick phenology studies.

Alpha‑gal syndrome (AGS) is a tick bite-induced, IgE‑mediated allergy to the carbohydrate galactose‑α‑1,3‑galactose (α‑Gal), characterised by delayed-onset hypersensitivity to mammalian meat and other mammal‑derived products. AGS occurs globally where ticks bite humans, with Australia experiencing some of the highest rates of AGS prevalence worldwide. Existing studies from North American and European tick species suggest that some ticks can produce α-Gal in their salivary glands, and that expression varies with feeding stage. However, comparable quantitative data are absent for the causative agent of AGS in Australia, the eastern paralysis tick, Ixodes holocyclus. Little is known about how much α‑Gal I. holocyclus produces in its salivary glands, dynamics of α‑Gal levels during blood feeding, or how host species influence α‑Gal production.

To address this, indirect enzyme‑linked immunosorbent assays (ELISAs) will be used to quantify α‑Gal levels in I. holocyclus salivary glands across the feeding cycle and between different host species. By generating quantitative profiles of α‑Gal abundance and integrating these with complementary localisation studies, this work aims to establish the first systematic assessment of α‑Gal production dynamics in I. holocyclus. These data will provide critical insight into how tick biology and feeding behaviour shape α‑Gal exposure and AGS risk in Australia.