Recent zoonotic disease emergences emphasize the importance of studying wildlife parasite communities. As wild hosts frequently harbour diverse parasite species, understanding the drivers of multiple infection patterns in free-ranging hosts is critical for elucidating the ecological and epidemiological dynamics of parasite communities. In this study, we analysed co-infection patterns in European roe deer (Capreolus capreolus) inhabiting a fragmented rural landscape in southwestern France. Using data from 130 samples of GPS-tracked deer, we examined the influence of proximity to livestock, host activity levels, age, sex and between-parasite interactions on the presence of 11 parasitic taxa. Hierarchical modelling of species communities (HMSC) revealed that proximity to livestock significantly increased the likelihood of infection with orofecally transmitted parasites (Toxoplasma gondii, gastrointestinal parasites). Sex and age were other key predictors, with males and juveniles exhibiting a higher frequency of parasite presence, likely influenced by hormonal and immune system differences. Activity levels showed distinct age-related effects, with higher activity levels being positively associated with increased parasite prevalence in yearlings, but not in adults. In contrast, parasite association patterns within individual hosts were weak, suggesting minimal interactions between parasite species. Our findings highlight the interplay between exposure and susceptibility in shaping co-infection patterns and underscore the value of hierarchical modelling approaches in multi-parasite systems.

Anaplasmosis is a significant tick-borne disease (TBDs) caused by Anaplasma that affecting ruminant health and production worldwide. This study aimed to identify Anaplasma spp. infection using molecular as a fast diagnostic tool, perform a phylogenetic analysis and evaluate associated risk factors for combating Anaplasma spp. infection in small-scale livestock farms in Thailand. Total 963 blood samples from ruminants were collected from 125 farms across 4 regions of Thailand. Molecular diagnosis of Anaplasma spp. targeted the msp4 gene using conventional polymerase chain reaction (PCR) was performed and reported to the farmers within 14 days. Positive PCR products were purified, sequenced, and analysed the phylogenetic. Associated risk factor evaluations were conducted using R software. The overall prevalence of Anaplasma spp. infection in ruminants was 26.90%. The highest prevalence was observed in bullfighting cattle (47.06%), followed by beef cattle (35.75%), dairy cattle (21.73%), and goats (6.67%), with no infection in buffalo. Regionally, the Northern region had the highest prevalence (49.01%), followed by the Southern (25.88%), Central (22.01%), and Northeastern (13.81%) regions. Anaplasma spp. was commonly detected in Phrae, Chiang Rai, and Tak provinces. Sequencing confirmed A. marginale 99.64% to 99.76% identity to sequences in GenBank. Risk factors associated with A. marginale infection were history of TBDs on farm, animal illnesses, responsible person for treatment, and improper faeces removal practices. This study revealed a moderate to high Anaplasma infection across four regions. These findings underscore the need for enhanced tick control measures on farms, should be strictly implemented and promoted to reduce disease prevalence.

Rosacea is a chronic inflammatory skin disease affecting approximately 5.4% of the world population. Among its pathogenic factors is infestation by Demodex spp. Standardized skin surface biopsy (SSSB) and direct microscopic examination (DME) are widely used methods to measure Demodex spp density (Dd); however, there is no agreement on the method of choice, nor the prevalence of infestation in rosacea patients. This study compared both techniques in rosacea patients. A prospective study was conducted with 61 patients diagnosed with rosacea by dermatologists from two dermatology centres. Dd was evaluated using SSSB and DME in each patient. Results, median sampling time and reported pain were analyzed using appropriate statistical methods. The median Dd was significantly higher with SSSB (11 mites/cm2) compared to DME (1 mites/cm2; P < 0.001). Infestation (>5 mites/cm2) was detected in 64% of patients with SSSB and in 28% with DME (P < 0.001). The median sampling time was longer for SSSB (60 s) than for DME (30 s; P < 0.001). Both methods were associated with mild pain, slightly lower with DME (P = 0.033). SSSB proved more effective than DME for detecting Demodex spp. in rosacea, identifying a greater total number of mites and a higher percentage of infestation. Up to 64% of rosacea patients showed infestation with Demodex spp. using the SSSB technique. The results reinforce the use of SSSB as the standard technique for diagnosing Demodex spp. infestation in rosacea patients.

Genital schistosomiasis, caused mainly by infection with Schistosoma haematobium flukes, causes a variety of symptoms and significant complications in men and women. With high levels of migration from sub-Saharan Africa to Europe and North America, genital schistosomiasis is likely to be encountered more frequently by clinicians in non-endemic areas. In this article, we review the current knowledge of genital schistosomiasis in non-endemic areas, available guidelines and barriers to clinical care of patients. Future work to address these barriers will likely improve care for patients with this neglected and stigmatized disease.

Exposure to environmentally transmitted parasites should increase with population density due to accumulation of infective parasites in space. However, resource competition also increases with density, lowering immunity and increasing susceptibility, offering an alternative pathway for density-dependent infection. To test the relationships between these two processes and parasitism, we examined associations between host density, resource availability, immunity, and counts of 3 common helminth parasites using a long-term study of red deer. We found evidence that immunity increased with resource availability while parasite counts declined with immunity. We also found that greater density correlated with reduced resource availability, and while density was positively associated with both strongyle and tissue worm burdens, resource availability was independently and negatively associated with the same burdens. Our results support separate roles of density-dependent exposure and susceptibility in driving infection, providing evidence that resource competition is an important driver of infection, exacerbating effects of density-dependent increases in exposure.

Parasitic nematodes within Onchocercidae are a diverse group transmitted by hematophagous arthropods. This study investigated the molecular occurrence of filarioid nematodes in 93 wild mammals from the Amazon, Cerrado and Pantanal biomes in Brazil, based on the analysis of the mitochondrial genes 12S ribosomal DNA gene (12S rDNA) and cytochrome c oxidase subunit I gene (COI). Conventional polymerase chain reaction (cPCR) targeting the 12S rDNA gene yielded positive results in 14·44% (13/93) of the samples, including 9·86% of jaguars (7/71), 50% of pumas (1/2), 12·5% of giant anteaters (1/8), 50% of ocelots (1/2) and 60% of crab-eating foxes (3/5). Among the 12S-positive samples, 46% (6/13) also tested positive for the COI gene; however, only 1 sequence was suitable for further analysis. Phylogenetic analyses based on 12S gene sequences revealed 4 distinct lineages within the family Onchocercidae. Groups Ia and Ib, composed of Cerrado and Pantanal sequences from jaguars, formed sister clades to Brugia pahangi and Malayfilaria sofiani, respectively. The sequence from the giant anteater (Group Ic) was more divergent, forming a sister clade to species of the genera Malayfilaria, Wuchereria, and Brugia. Group II included sequences closely related to Dirofilaria immitis and D. striata, encompassing samples from crab-eating foxes, ocelots and a puma. These findings suggest that several wild mammal species may serve as reservoirs for previously uncharacterized Onchocercidae nematodes. Our findings expand the existing knowledge on host associations of filarioid nematodes infecting wild mammals from the Pantanal, the Cerrado and the Amazon Rainforest.

The objective of this study was to assess the potential role of aquatic biofilms as natural reservoirs for Blastocystis. For this purpose, surface water (n = 4) and biofilm samples (n = 8) were collected from a stream nearby an urban area characterized by limited sanitation infrastructure and a high prevalence of Blastocystis in humans. Blastocystis cysts were detected in three of the four water samples and seven of the eight biofilm samples using fluorescence microscopy. Furthermore, viable cysts were identified exclusively in biofilm samples (five of the eight), while no live cysts were detected in water samples. These findings indicate that aquatic biofilms provide a habitat where Blastocystis cysts can adhere and remain viable, potentially contributing to their environmental accumulation. In addition, molecular characterization of the five isolates identified subtypes ST8 (allele 21) and ST3 (allele 36). This study is the first to report the detection and identification of viable Blastocystis subtypes in aquatic biofilms. The analysis of biofilms by fluorescence microscopy, as demonstrated here, offers a promising approach for monitoring Blastocystis and could serve as an alternative to traditional water sampling methods.

The crayfish plague pathogen Aphanomyces astaci (Oomycota: Saprolegniales) is native to North America but expanded with its crayfish hosts to other regions. In most of its invaded range, A. astaci haplotypes are associated with specific American crayfish, probably due to introduction bottlenecks, but haplotype diversity is higher and clear host-specific associations are lacking in its native range. However, little is known about the infection rate and load of this pathogen in North America. We investigated the distribution, prevalence and genetic variation of A. astaci in Pennsylvania (eastern USA), where multiple native and introduced crayfish species (family Cambaridae) occur. We used A. astaci-specific quantitative PCR to screen 533 individuals representing 8 crayfish species (2 Cambarus and 6 Faxonius) from 49 sites. Faxonius limosus, an American species first introduced to Europe and carrier of A. astaci genotype group E, was of particular interest. We confirmed A. astaci infections in 76% of sites in all but 1 host taxon, with the pathogen infection rate and load comparable to established populations of North American crayfish studied in Europe and Japan. Despite the absence of highly infected hosts, we genotyped A. astaci from 14 sites. We only detected 2 mitochondrial haplotypes, but nuclear markers indicated the presence of at least 4 distinct pathogen genotypes, none documented from invaded areas in Europe or Asia. Genotype group E was not detected in F. limosus, possibly due to limited spatial distribution of the original strain. Our results highlight both benefits and limitations of combining multiple pathogen genotyping methods.

A species of acanthocephalan collected from the hindgut of Larimichthys crocea was identified as Longicollum pagrosomi Yamaguti, 1935 based on morphological characteristics. The complete mitochondrial genome of this parasite was sequenced. The mitogenome exhibited a circular structure with a total length of 14 632 bp, containing 12 protein coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and 2 major non-coding regions. The most frequently used start codon was GTG, and the most abundant amino acid was valine. The phylogenetic analyses of the mitogenome using Bayesian inference and maximum likelihood methods showed that the genus Longicollum formed a sister clade to the genus Pomphorhynchus, supporting the monophyly of Pomphorhynchus. This study reported a new host for L. pagrosomi and revealed the first complete mitogenome sequence of the genus Longicollum.

Members of Sinistroporomonorchis Wee, Cutmore, Pérez-del-Olmo & Cribb, 2020 represent a small group of trematodes belonging to the Monorchiidae Odhner, 1911 with 5 species described from mugilid hosts. Specimens consistent with the generic concept of Sinistroporomonorchis were obtained from Floridichthys polyommus (Cyprinodontidae); most of them were juveniles from 4 localities within the Yucatán Peninsula. After a detailed morphological examination including scanning electron microscopy images and a principal component analysis, the specimens collected represented a new species, Sinistroporomonorchis bolini n. sp. The new species can be differentiated by the presence of an overall large pharynx including the proportion of pharynx width to oral sucker width, a uterus arranged in 2 main lateral fields, and by presenting robust caeca. In addition, sequences of the 28S of large subunit of nuclear ribosomal RNA and cox1 of the mitochondrial DNA were obtained. Phylogenetic trees inferred from each dataset, placed all the specimens in a monophyletic clade, confirming that the isolates belonged to the same species. The new species is the sixth described for the genus Sinistroporomonorchis, the fifth described from the Yucatán Peninsula and the first described from a non-mugilid host.

The water buffalo farm with intensive breeding techniques promotes the spread of lice (Haematopinus tuberculatus), leading to a reduction in meat and milk productions. Current control measures include the use of chemicals, which in the long-term lead to the development of resistance. Given the lack of alternative solutions, the aim of this study was to evaluate the repellent effect of a low impact by-product, the wood vinegar (WV), against H. tuberculatus using a new in vitro bioassay test. The test consisted of a glass Petri dishes subdivided in 3 separate areas. WV was tested at different concentrations (100%, 75%, 50%, 25%). Each of the 3 replicates was performed with 10 adults, at 27 °C and 75% relative humidity. Observations were made 5, 15, 30, 60, 90, 120 and 180 min after application to evaluate movement, the living/dead ratio and the ability to overcome the obstacle area of the lice, in terms of comparative avoidance (%). Additional in vitro cytotoxicity tests were performed. The test performed showed a repellent effect of 77% for the 100% WV concentration against lice of both sexes 30 min after exposure, similar (P < 0.05) to the repellent effect of deltamethrin (77%). The in vitro bioassay developed during the experiment proved to be reliable and can be used to evaluate the repellent effect of new molecules against lice before testing them in vivo. Furthermore, WV has a potential to be a valid tool for the control of buffalo pediculosis, although in vivo studies have to be undertaken.

Following the recent report of strongyloidiasis caused by Strongyloides fuelleborni within a semi-captive colony of baboons in a UK safari park, we investigated the genetic relationships of this isolate with other Strongyloides isolates across the world. Whole-genome sequencing data were generated with later phylogenetic analysis of mitochondrial (mt) cytochrome oxidase subunit 1 (cox1) and nuclear ribosomal 18S sequences against 300 published Strongyloides reference genotypes. The putative African origin of the UK S. fuelleborni was confirmed and full-length mt genome sequences were assembled to facilitate a more detailed phylogenetic analysis of 14 mt coding regions against all available Strongyloides species. Our analyses demonstrated that the UK isolate represented a novel African lineage not previously described. Additional complete mt genomes were assembled for several individual UK safari park worms to reveal a slightly altered mt genome gene arrangement, allowing clear separation from Asian S. fuelleborni. Furthermore, these UK worms possessed expanded intergenic regions of unknown function that increase their mt genome size to approximately 24 kilobases (kb) as compared with some 16 kb for Asian S. fuelleborni; this may have arisen from unique populational founder and genetic drift effects set within the peculiar mixed species baboon and drill ancestry of this semi-captive primate colony. A maximum likelihood phylogeny constructed from 14 mt coding regions also supported an evolutionary distinction between Asian and African S. fuelleborni.

We analysed the early results of a screening and management protocol of imported female genital schistosomiasis (FGS) among migrant women from endemic countries. In total we screened 136 women, from which 39 had suspicion of FGS (serology-positive test and clinical signs and symptoms compatible). Median age was of 42.7 years [interquartile range (IQR 35–45)], median time living in the Europe (EU) was of 14 years (IQR 10–19) and all of them were coming from a West African country, mainly Senegal (17 out of 39; 43.6%). All of them had 1 or more clinical genitourinary findings [median 5 (IQR 2–6)], being the most prevalent pelvic pain, vaginal discharge and menstrual disorders. According to the protocol, colposcopy and cytology examination was performed in 11 participants, from whom 7 had findings compatible with FGS and 5 had low-grade cervical dysplasia with human papillomavirus (HPV)-negative results. After specific treatment with praziquantel (PZQ), we observed a high rate of resolution of clinical signs and symptoms, serology clearance at the 12th month of follow-up. Colposcopy lesions of 3 women assessed at the end of follow-up were fully resolved. Our findings and previous research support the implementation of management protocols of FGS in non-endemic countries, in spite of the knowledge gaps that still remain. Clinical trials need further assessment to determine the efficacy of PZQ, new diagnostic tools and the interaction between FGS, HPV and cervical cancer.

Parasites of the Leishmania species have been observed to infect macrophages and thereby modulate the host microbicidal responses, resulting in a wide spectrum of diseases. A comprehensive experimental mapping of the relationship between the double-stranded RNA protein kinase R (PKR) and NF-κB pathways in the outcome of the infection was conducted in an effort to improve the understanding of the biology associated with the parasites–host cell interaction. The results showed that in the absence of PKR and Type I Interferon (IFN) signalling, L. major infection was enhanced. The levels of PKR and gene promoter activation were evaluated. The results showed that infection did not induce PKR expression by inhibiting the phosphorylation of STAT1 and subsequent binding in the PKR promoter. However, infection induced PKR phosphorylation but did not prevent subsequent signalling through this pathway. To address the role of activation of these signalling, the induction of PKR-dependent gene expression was examined. Activation of the classical p65/p50 dimer was found to be dependent on the PKR in the L. major infection, which was essential for the induction of iNOS, IFNβ and tumour necrosis factor expression. In addition, macrophages treated with nuclear factor-kB inhibitors were more susceptible to infection. Furthermore, translocation of the p65/p50 to the promoters of these genes increased in a PKR-dependent manner. Collectively, these results suggest that macrophages retain their ability to induce important downstream effectors in PKR signalling. These effectors contribute to protection in pathogenesis, reducing parasite proliferation and regulating the inflammatory genes that, consequently, modulate the activation state of macrophages during infection.

As part of a broad survey of the trematodes of damselfishes (Pomacentridae) in the tropical Indo-West Pacific, zoogonids were collected from multiple localities in Australia, New Caledonia, and French Polynesia. All zoogonid specimens collected were consistent with the subfamily Lecithostaphylinae, and morphological and molecular data (ITS2 and 28S rDNA, and cox1 mtDNA) were generated for most host-locality combinations to enable an integrative species delimitation. The collection comprised three species: Deretrema stratiotes n. sp. from four species of Abudefduf Forsskål from Ningaloo Reef in Western Australia, and two species consistent with the genus Lecithostaphylus Odhner, 1911 for which Innuptacola n. gen. is proposed based on phylogenetic and morphological distinction, the type-species I. gibsoni (Cribb, Bray & Barker, 1992) n. comb. (= L. gibsoni) from six species of Abudefduf in Ningaloo Reef, Queensland and New Caledonia, and I. torquata n. sp. from 12 pomacentrid species in Ningaloo Reef, the Great Barrier Reef in Queensland, and the Gambier Islands in French Polynesia. The new collection demonstrates that some zoogonid species are geographically widespread (from the Pacific Ocean to the Indian Ocean) and can infect a broad range of hosts (multiple genera within a family), whereas others are apparently geographically restricted and exhibit higher host-specificity (fishes within a single genus).

Hookworms are common parasites of Eurasian badgers (Meles meles), typically identified as Uncinaria criniformis. The taxonomic distinction from Uncinaria stenocephala, a species found in dogs and foxes, has long been debated. In this study, we molecularly characterized U. criniformis from a Eurasian badger in Romania using genome skimming. We assembled the complete mitochondrial genome and internal transcribed spacer (ITS) rDNA region from 2 adult hookworms morphologically consistent with U. criniformis. Phylogenetic analysis of 12 mitochondrial protein-coding genes demonstrated strongly supported clade of U. criniformis with Ancylostoma spp. ITS rDNA and cox1 sequence comparisons revealed only 92.4–92.8% and 88.0–88.5% identity, respectively, between U. criniformis and U. stenocephala, confirming their molecular distinctiveness. In contrast, our sequences showed >99% identity to sequences from Arthrostoma leucurus, a hookworm recently described from the Asian badger (Meles leucurus), suggesting conspecificity. These findings support the validity of U. criniformis as a distinct species parasitizing M. meles, and we propose A. leucurus as a junior synonym of U. criniformis. Our results highlight the polyphyly of the genus Uncinaria and point to the need for broader mitogenomic sampling of hookworms. The molecular markers generated here provide a reference for future parasitological surveys and wildlife disease studies.

Birds possess the most diverse assemblage of haemosporidian parasites, although the true diversity is unknown due to high genetic diversity and insufficient sampling across all avian clades. Waterfowl (Order Anseriformes) are an ideal group to discover hidden parasite diversity and examine the role of host ecology in parasite transmission. Waterfowl contain 2 distinct feeding guilds, dabbling and diving, which differ in niche utilization that likely alters vector encounter rates and haemosporidian parasite risk. To determine the role of feeding guild in haemosporidian parasitism we analysed 223 blood samples collected by hunters from the upper Midwest of the United States from 2017 to 2019. Fifty-four individuals were infected by haemosporidian parasites (24·2% prevalence). Infection prevalence differed significantly between dabbling (34·9%, n = 109) and diving (14·0%, n = 114) ducks. Feeding guild was the only host trait that could predict haemosporidian infection risk, with a significantly higher risk in dabbling ducks. Twenty-four haemosporidian lineages were identified, with 9 identified for the first time. Thirteen lineages were found only in dabbling ducks, 5 only in diving ducks and 6 in both feeding guilds. Community analysis showed that each feeding guild harboured a unique parasite community. There was no phylogenetic signal of feeding guild within a phylogenetic reconstruction of North American waterfowl haemosporidian lineages. Our results demonstrate that waterfowl contain a diverse and distinct community of haemosporidian parasites. The unique composition of each feeding guild determines not only haemosporidian infection risk but also community structure. This is the first report of such an impact for waterfowl feeding guilds.