Human cryptosporidiosis diagnosed in Western Australia: a mixed infection with Cryptosporidium meleagridis, the Cryptosporidium mink genotype, and an unknown Cryptosporidium species.

This report describes a case of cryptosporidiosis from an immunocompetent patient from Perth, Western Australia, suffering from diarrhea and a spectrum of other symptoms. Molecular identification revealed that this patient was infected with three Cryptosporidium species-Cryptosporidium meleagridis, the Cryptosporidium mink genotype, and an unknown Cryptosporidium species.

Enhanced detection of Giardia duodenalis mixed assemblage infections in pre-weaned dairy calves using next generation sequencing.

Giardia duodenalis is one of the most common parasitic causes of gastrointestinal illness in humans worldwide with widespread infections in mammalian hosts. It frequently infects cattle, producing a high number of cysts. Cattle can harbor both host-adapted assemblage E and human pathogenic assemblages A and B. Previous studies have demonstrated that conventional molecular methods lack the sensitivity required for detecting mixed infections and that the occurrence of mixed infections in cattle are likely underestimated. To investigate the presence of mixed assemblage infections in cattle, 2539 pre-weaned dairy calves from the United Stated were screened for the presence of G. duodenalis using molecular tools. Next generation amplicon sequencing (NGS) was then performed for a subset of around 30% of positive samples (n = 314) and the ability of NGS and Sanger sequencing to detect mixed assemblage infections was compared. The overall prevalence of G. duodenalis in pre-weaned dairy calves in the sample using PCR was high (1013/2539; 39.9%). Molecular genotyping identified only assemblage A and E, with assemblage E as the predominant assemblage. Out of the 314 samples examined by both Sanger and NGS, 9 samples (2.9%) were identified as mixed A/E infections by Sanger while NGS identified 56 samples (17.8%), which was six-times more mixed infections compared with Sanger sequencing. NGS demonstrated superior sensitivity to Sanger in detecting assemblages present in low abundances. The percentage of mixed A/E infections found in the sampled dairy calves was higher than was hypothesized using values from the literature. This underestimation could be present in the wider cattle population as well, though further exploration would be needed to verify that claim. These findings highlight the advantages of NGS application in molecular epidemiological studies of Giardia. To better understand Giardia epidemiology, establish routes of transmission, and assess the potential role of cattle and other animals as a source of environmental contamination with zoonotic assemblages it is necessary to uncover mixed assemblage infections.

Blastocystis in domesticated and wild mammals and birds.

Blastocystis is a ubiquitous parasite that infects a broad range of vertebrate hosts including humans and domestic and wild animals. While human infections have been occasionally associated with gastrointestinal illnesses and/or urticaria, animal infections are not usually associated with disease. However, from a public health perspective, most subtypes isolated in humans have also been isolated from animals raising the question of the importance of animal reservoirs in the epidemiology of this parasite. The identification of Blastocystis in water supplies suggests water can be a potential vehicle in the transmission of this parasite not only for humans but also for animals. In addition, Blastocystis has been detected in retail fresh produce. Knowledge of this parasite has greatly expanded in the last two decades from simple microscopic observations to the application of molecular tools to explore Blastocystis taxonomy and epidemiology. This review provides a comprehensive overview of Blastocystis in animals highlighting the subtype diversity of this widespread and genetically diverse parasite in different animal groups. This information will be useful in understanding the current status of taxonomy, epidemiology, zoonotic potential, and public health importance of Blastocystis.

Differences in the occurrence and epidemiology of cryptosporidiosis in Aboriginal and non-Aboriginal people in Western Australia (2002-2012).

Cryptosporidiosis is a diarrhoeal illness caused by the protozoan parasite Cryptosporidium. In Australia, very little is known about the epidemiology of cryptosporidiosis in Aboriginal peoples. The present study analysed long-term cryptosporidiosis patterns across Western Australia (WA) (2001-2012), combined with genotyping and subtyping data at the 18S and glycoprotein 60 (gp60) loci respectively. Comparison of cryptosporidiosis notifications between Aboriginal and non-Aboriginal people in WA, revealed that notification rates among Aboriginal people were up to 50 times higher compared to non-Aboriginal people, highlighting the burden of the disease in this population. More than 90% of notifications were in Aboriginal children aged 00-04years, who had a notification rate 20.5 times higher than non-Aboriginal children in the same age group. Cryptosporidium hominis was the predominant species infecting both Aboriginal and non-Aboriginal people. However, Aboriginal people were mainly infected with the C. hominis IdA15G1 subtype, whereas non-Aboriginal people were predominantly infected with the IbA10G2 subtype. To control cryptosporidiosis in Aboriginal populations in Australia, effective health interventions/promotions need to be a priority for public health research and action.

Metabolomic profiling of faecal extracts from Cryptosporidium parvum infection in experimental mouse models.

Cryptosporidiosis is a gastrointestinal disease in humans and animals caused by infection with the protozoan parasite Cryptosporidium. In healthy individuals, the disease manifests mainly as acute self-limiting diarrhoea, but may be chronic and life threatening for those with compromised immune systems. Control and treatment of the disease is challenged by the lack of sensitive diagnostic tools and broad-spectrum chemotherapy. Metabolomics, or metabolite profiling, is an emerging field of study, which enables characterisation of the end products of regulatory processes in a biological system. Analysis of changes in metabolite patterns reflects changes in biochemical regulation, production and control, and may contribute to understanding the effects of Cryptosporidium infection in the host environment. In the present study, metabolomic analysis of faecal samples from experimentally infected mice was carried out to assess metabolite profiles pertaining to the infection. Gas-chromatography mass spectrometry (GC-MS) carried out on faecal samples from a group of C. parvum infected mice and a group of uninfected control mice detected a mean total of 220 compounds. Multivariate analyses showed distinct differences between the profiles of C. parvum infected mice and uninfected control mice,identifying a total of 40 compounds, or metabolites that contributed most to the variance between the two groups. These metabolites consisted of amino acids (n = 17), carbohydrates (n = 8), lipids (n = 7), organic acids (n = 3) and other various metabolites (n = 5), which showed significant differences in levels of metabolite abundance between the infected and uninfected mice groups (p < 0.05). The metabolites detected in this study as well as the differences in abundance between the C. parvum infected and the uninfected control mice, highlights the effects of the infection on intestinal permeability and the fate of the metabolites as a result of nutrient scavenging by the parasite to supplement its streamlined metabolism.

Molecular characterization of Cryptosporidium spp. from wild rats and mice from rural communities in the Philippines.

In order to examine the prevalence of Cryptosporidium in wild rodents in the Philippines and understand the role wild rodents play in the transmission of this parasite to humans and livestock, 194 fecal samples from wild rats and mice from Luzon and Mindoro islands were examined. Molecular screening at the 18S and actin gene loci identified an overall prevalence of 25.8% (95%CI: 19.8, 32.5). Sequence and phylogenetic analysis of both loci identified C. parvum, C. muris, C. scrofarum, rat genotypes I-IV and a C. suis-like genotype in the rat-derived isolates and is the first report of C. suis-like and C. scrofarum in rats. Mixed infections were identified in 24% of the Cryptosporidium positive isolates. Rat genotypes II, III and IV showed high intragenotypic variation at the 18S gene locus compared to the actin locus.