Conference Agenda

Cryptosporidium is a major enteric zoonotic protozoan parasite with a wide host range, causing gastrointestinal disease in humans and animals. Livestock, particularly calves, serve as an important zoonotic reservoir for Cryptosporidium parvum, the main zoonotic species. In the present study, 300 cattle faecal samples (200 calves and 100 adult cattle) from Western Australia (WA) were screened for Cryptosporidium by PCR and sequence analysis at the18S rRNA locus. Cryptosporidium parvum positives were analysed using multi locus sequence typing (MLST) of five polymorphic loci including the hypervariable gp60 gene and compared to previously typed human C. parvum samples from WA.

Results revealed that C. parvum was the only species detected in both calves and adult cattle with three C. parvum gp60 subtype families identified; IIaA18G3R1, IIaA19G4R1 and IIaA20G3R1. MLST analysis demonstrated limited genetic diversity among cattle and human C. parvum isolates, with most isolates clustering within a single dominant clade. The intermixing of host-derived isolates supports potential zoonotic transmission of C. parvum.

Cryptosporidium and Giardia are globally important enteric protozoa with broad host ranges and significant One Health implications. However, molecular epidemiological data in Australian goats remain limited. This study investigated the molecular prevalence, species composition and genotype diversity of Cryptosporidium and Giardia in Australian dairy goats. A cross-sectional survey (2023–2024) was conducted involving 386 goats (4 weeks–12 months old) from 61 dairy herds across six states. DNA samples were analysed using nested PCR and Sanger sequencing for species and assemblage identification. Cryptosporidium was detected in 6.5% of samples and Giardia in 9.3%. Three Cryptosporidium species were identified: Cryptosporidium xiaoi, C. ubiquitum, and C. muris, with the latter two recognised as zoonotic. Giardia duodenalis assemblages AI and E were detected, including five novel assemblage E variants. C. muris and a zoonotic Giardia sub-assemblage AI are reported for the first time in Australian goats, alongside two novel C. xiaoi genotypes. Although overall prevalence was low, the detection of zoonotic genotypes highlights the role of young goats as reservoirs for infection. The absence of C. parvum, a major zoonotic species globally, suggests distinct regional transmission dynamics. These findings provide baseline molecular data to inform surveillance, risk assessment and One Health management strategies in Australia.

Cryptosporidium spp. and Giardia duodenalis are globally significant enteric protozoa affecting livestock health, productivity and public health through their zoonotic potential. In pigs, these infections can impair growth performance and welfare, yet molecular epidemiological data in Australian production systems remain limited. This study aimed to determine the prevalence, distribution and genetic diversity of Cryptosporidium spp. and G. duodenalis in pigs across Victoria. A cross-sectional survey was conducted using 626 faecal samples collected from pigs of different age groups across 69 commercial farms. Samples were screened using nested PCR, and amplicons were subjected to Sanger sequencing. Phylogenetic analyses were conducted to identify species, assemblages/subtypes and determine their genetic relationships. Preliminary findings have identified Cryptosporidium scrofarum, C. suis and the zoonotic species C. ubiquitum, as well as G. duodenalis assemblages A and E. These results indicate the presence of both host-adapted and zoonotic genotypes in Victorian pig populations. This study will generate the first comprehensive molecular epidemiological dataset for these protozoa in Victorian pigs, providing critical insights into infection dynamics and zoonotic risk. The findings will inform evidence-based parasite control, strengthen biosecurity strategies and support sustainable productivity in the Australian pork industry.

Building on our previous report of high prevalence of soil-transmitted helminth (STH) infections among Myanmar schoolchildren (Aung et al., Infectious Diseases of Poverty, 2022), we conducted additional molecular screening of archival stool samples from the same cohort in Phyu Township, Bago Region, to investigate additional helminth infections. We also report finding of other helminths by Kato-Katz in the previous study that were not previously published. Stool samples utilised in this study were collected in 2016 and the DNA extracted in 2017 and kept stored at -20°C until further molecular characterisation in this study in 2025. Using quantitative PCR (qPCR), we detected Schistosoma DNA in two of 264 samples, Strongyloides stercoralis DNA in twelve, and Ancylostoma ceylanicum in eleven. Although sequencing of the Schistosoma-positive samples was unsuccessful, the molecular evidence aligns with other recent reports suggesting emerging or cryptic transmission of schistosomiasis in Myanmar. The epidemiology of schistosomiasis in the region remains poorly defined, highlighting the need for targeted snail surveys, environmental DNA (eDNA) monitoring, and host sampling to confirm transmission foci. This study demonstrates the added value of molecular diagnostics for complementing traditional parasitological methods and guiding surveillance and control strategies in areas of emerging endemicity.