International journal for parasitology最新文献

{"title":"Protection against anuran lungworm infection may be mediated by innate defenses rather than their microbiome.","authors":"Chava L Weitzman, Gregory P Brown, Kimberley Day, Catherine M Shilton, Karen Gibb, Keith Christian","doi":"10.1016/j.ijpara.2025.01.010","DOIUrl":"https://doi.org/10.1016/j.ijpara.2025.01.010","url":null,"abstract":"<p><p>Host-associated microbiomes provide protection against disease in diverse systems, through both direct and indirect interactions with invaders, although these interactions are less understood in the context of non-gut helminth infections in wildlife. Here, we used a widespread, invasive host-parasite system to better understand helminth-amphibian-microbiome dynamics. We focus on cane toads and their lungworm parasites, which invade the host through the skin, to study the interactions between lungworm infection abundance and skin and gut (colon) bacterial microbiomes. Through two experiments, first reducing skin bacterial loads, and second reducing bacterial diversity, we found no evidence of protection by skin bacteria against infection. We also did not find divergent gut communities dependent on lungworm infection, signifying little to no immune modulation from infection causing changes to gut communities, at least in the first month after initial parasite exposure. In light of previous work in the system, these results underscore the contribution of toads' innate susceptibility (including possible protection provided by skin secretions) rather than skin microbes in determining the chance of infection by these macroparasites.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dirofilaria spp. infection in cats from the Mediterranean basin: diagnosis and epidemiology.","authors":"Mariaelisa Carbonara, Livia Perles, Luigi Venco, Simona Gabrielli, Vanessa R Barrs, Guadalupe Miró, Elias Papadopoulos, Clara Lima, Emilie Bouhsira, Gad Baneth, Nikola Pantchev, Roberta Iatta, Jairo Alfonso Mendoza-Roldan, Nicola Decaro, Bettina Schunack, Giovanni Benelli, Domenico Otranto","doi":"10.1016/j.ijpara.2025.01.011","DOIUrl":"https://doi.org/10.1016/j.ijpara.2025.01.011","url":null,"abstract":"<p><p>Dirofilaria immitis and Dirofilaria repens, causing heartworm disease and subcutaneous dirofilariosis, respectively, are zoonotic mosquito-borne filarioids infecting a plethora of hosts including cats. Only fragmented data are available on the diagnosis and epidemiology of feline dirofilariosis. We assessed the occurrence of both nematode infections, their risk factors and clinicopathological abnormalities in cats, from six countries of the Mediterranean Basin. In addition, Wolbachia spp. endosymbionts were assessed in Dirofilaria spp.-positive animals. Blood and sera samples were obtained from cats with outdoor access from Spain (n=354), Portugal (n=287), Italy (n=125), Greece (n=116), Israel (n=101) and France (n=100). Cat sera were tested by both direct antigenic (SNAP test, commercial ELISA kit) and indirect antibodies (in-house ELISA) serological tools, and blood samples by real time and conventional PCR targeting Dirofilaria spp. DNA, followed by sequencing. A statistical analysis was run to assess the link between Dirofilaria spp. infection and independent variables, as well as among feline immunodeficiency virus (FIV) and/or feline leukaemia virus (FeLV) co-infections, and clinicopathological abnormalities. Overall, 3.8% (i.e., 41/1,083) cats scored positive for Dirofilaria spp. infection with prevalences ranging from 2% in Israel to 7.8% in Greece. Of the 41 positive cats, 16 were infected by D. immitis (by SNAP test and/or PCR) and two by D. repens (by PCR); the remaining animals were antibody-positive for Dirofilaria spp. using the in-house ELISA. Wolbachia DNA was detected in one D. immitis-infected cat. Nematode positivity was significantly associated with age, breed, hyporexia, dandruff, and dyspnoea. This study provides data on the prevalence of Dirofilaria spp. infection in cats from the Mediterranean Basin, as well as new insights on its diagnosis, revealing the importance of performing strategic chemoprophylactic treatments for cats living in areas where the infection is also endemic in dogs.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bat microfilariae in the cityscape: a transmission tale between bats, mites, and bat flies","authors":"Román Espinal-Palomino ,&nbsp;Ana Celia Montes de Oca-Aguilar ,&nbsp;Martha Pilar Ibarra-López ,&nbsp;Víctor M. Vidal-Martínez ,&nbsp;Carlos N. Ibarra-Cerdeña","doi":"10.1016/j.ijpara.2024.11.001","DOIUrl":"10.1016/j.ijpara.2024.11.001","url":null,"abstract":"<div><div><em>Litomosoides</em> includes filarial nematodes capable of infecting various vertebrate species. While <em>Litomosoides</em> has been extensively studied in rodents, research on its association with bats remains limited. The transmission dynamics of this parasite are complex, involving moving between different invertebrate hosts before reaching the final host. Most investigations concerning microfilariae have concentrated on their morphological characteristics, with scant attention paid to ecological aspects, particularly in human-altered landscapes. This study represents the first known documentation of <em>Litomosoides</em> in bats within an urban environment. It investigates their response to urbanization in their interaction with the synanthropic bat <em>Artibeus jamaicensis</em> and its ectoparasites. The objective was to explore the influence of urban landscapes on <em>Litomosoides</em> prevalence in synanthropic hosts. Blood samples were collected along urban–rural gradients, and parasite presence was confirmed through direct observation in blood smears and PCR. Phylogenetic analysis based on the mitochondrial cytochrome <em>c</em> oxidase subunit 1 gene (COX1), which exhibited robust support values, indicates that the microfilaria found in <em>A. jamaicensis</em> is closely related to <em>Litomosoides chandleri</em>. However, it also suggests the possibility of an unidentified, and therefore potentially new, species within the genus <em>Litomosoides</em>. Additionally, <em>Litomosoides</em> DNA was detected in <em>Periglischrus iheringi</em> (Acari: Spinturnicidae) and in the bat fly <em>Trichobius intermedius</em> collected from the bat. The parasite sequences obtained from these three interacting species exhibited a genetic distance as low as 0.002. The highest prevalences were recorded in forested areas (28.6%) compared with urban areas (21.2%). However, within the urban landscape, prevalence varied from 3.8% to 21.2%, being highest in densely built-up areas. Analysis of the urban landscape suggested that the prevalence of <em>Litomosoides</em> in <em>A. jamaicensis</em> is the result of a multifactorial and synergistic process involving ectoparasite load, host abundance, and the extent of impervious surfaces (NDBI).</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 79-94"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dense aquatic vegetation can reduce parasite transmission to amphibians","authors":"Marin Milotic ,&nbsp;Dino Milotic ,&nbsp;Janet Koprivnikar","doi":"10.1016/j.ijpara.2024.11.003","DOIUrl":"10.1016/j.ijpara.2024.11.003","url":null,"abstract":"<div><div>Submerged aquatic vegetation (macrophytes) can provide prey with refuges from predators and may perform a similar role for interactions with other natural enemies such as parasites. This could occur by interfering with the ability of free-swimming infectious parasite stages to locate or move towards hosts, reducing infections. Alternatively, infections may increase if macrophytes reduce host anti-parasite behaviours such as detection or evasion. Both scenarios could be affected by macrophyte density and structural complexity. Here we investigated whether experimental infection of tadpoles (<em>Rana sylvatica</em> and <em>Rana pipiens</em>) by parasitic flatworms (the trematodes <em>Ribeiroia ondatrae</em> and <em>Echinostoma</em> spp. was affected by the presence of artificial vegetation with varying density and complexity (simple versus branching), as well as tadpole activity under these conditions. Macrophyte presence significantly reduced tadpole infection loads only in the highest density treatment, but there was no effect of structural complexity. Related to this, tadpoles spent significantly more time near aquatic vegetation when it was dense but showed no preference for either structural type. Our results indicate that aquatic vegetation can reduce parasite transmission in certain scenarios, with further studies needed to explore how structural complexity in natural systems can affect host-parasite interactions, considering the massive physical alterations possible through eutrophication and the introduction of invasive plant species.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 95-102"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do specialist and generalist parasites differ in their prevalence and intensity of infection? A test of the niche breadth and trade-off hypotheses","authors":"Sonia Cebrián-Camisón ,&nbsp;Josué Martínez-de la Puente ,&nbsp;María José Ruiz-López ,&nbsp;Jordi Figuerola","doi":"10.1016/j.ijpara.2024.11.009","DOIUrl":"10.1016/j.ijpara.2024.11.009","url":null,"abstract":"<div><div>Studying host specificity is crucial to understanding the ability of parasites to spread to new hosts and trigger disease emergence events. The relationship between host specificity and parasite prevalence and infection intensity, has typically been studied in the context of two opposing hypotheses. According to the trade-off hypothesis generalist parasites, which can infect a broad range of hosts, will reach a lower prevalence and infection intensity than more specialist parasites due to the higher costs to adapt to multiple host immune systems. In contrast, the niche breadth hypothesis proposes that generalists’ ability to infect more host species makes them more efficient in colonising host communities and thus they are found at higher prevalences and infection intensities. This study aims to test these hypotheses using the widespread avian malaria parasites of the genera <em>Plasmodium</em> and the related malaria-like parasite <em>Haemoproteus.</em> Overall, 1188 wild house sparrows from 17 localities in southwestern Spain were screened for parasite presence and intensity of infection. For each lineage found infecting house sparrows, we estimated host specificity as i) the number of different bird taxa infected by that lineage according to the MalAvi database and ii) an index that accounts for the phylogenetic relatedness between the host species. Parasite infections were recorded in 419 house sparrows, and eight <em>Plasmodium</em> and three <em>Haemoproteus</em> lineages were identified. Prevalence was positively associated with the number of host species. Lineages found in more localities showed both higher prevalence and host range. Overall, these results support the niche breadth hypothesis in relation to blood parasites infecting house sparrows.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 129-136"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The parasitic nematode Haemonchus contortus lacks molybdenum cofactor synthesis, leading to sulphite sensitivity and lethality in vitro","authors":"Robert A. Brinzer,&nbsp;Jennifer R. McIntyre,&nbsp;Collette Britton,&nbsp;Roz Laing","doi":"10.1016/j.ijpara.2024.11.004","DOIUrl":"10.1016/j.ijpara.2024.11.004","url":null,"abstract":"<div><div>Sulphite oxidase has an essential role in detoxifying environmental and endogenously generated sulphite into sulphate and requires the molybdenum cofactor (Moco) to function. Until recently it was believed that the synthesis pathway for Moco was so important for survival that it was conserved in all multicellular animals. Here we report the use of comparative genomics to identify the absence of the first enzyme involved in Moco synthesis in <em>Haemonchus contortus</em>, a highly pathogenic and economically important helminth of livestock that, similar to many parasitic nematode species, has proved difficult to maintain in vitro. We show that Moco deficiency in <em>Haemonchus</em> leads to a high sensitivity to environmental sulphite and limits the ability to maintain the early parasitic larval stages in vitro. Analogous losses in Moco synthesis in other recently sequenced nematode species are also identified. These findings may lead to improved culture methods for parasitic nematodes and to novel approaches for their control.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 117-128"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142768446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into extracellular vesicle biogenesis and secretion of the tapeworm Hymenolepis diminuta: host interaction and cultivation dynamics","authors":"Hynek Mazanec ,&nbsp;Javier Sotillo ,&nbsp;Peter Koník ,&nbsp;Nikol Bušková ,&nbsp;Jiří Kyslík ,&nbsp;Zdenko Gardian ,&nbsp;Tomáš Bílý ,&nbsp;Kateřina Jirků ,&nbsp;Roman Kuchta","doi":"10.1016/j.ijpara.2024.11.005","DOIUrl":"10.1016/j.ijpara.2024.11.005","url":null,"abstract":"<div><div>Extracellular vesicles (EVs) from parasites have been identified as potent modulators of host-parasite interactions. However, their biogenesis and secretory activity are still poorly understood. Here we present a comprehensive examination of the secretory dynamics of two distinct EV fractions isolated from the adult tapeworm <em>Hymenolepis diminuta</em>. Additionally, we perform a detailed analysis of changes in proteomic content and morphology during EV secretion, utilising electron tomography to shed light on a previously described novel mechanism of EV biogenesis via bead-like protrusion. Our findings reveal a significant decrease in EV secretion between 24 and 48 h of <em>in vitro</em> cultivation when external host stimuli are no longer present. Finally, this study addresses, for the first known time, the potential bias in EV analysis resulting from extended <em>in vitro</em> cultivation of model parasites.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 69-77"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mitogenomic analysis of the position of the Azygiidae and constituent genera, with a new species of Azygia","authors":"Danimar López-Hernández ,&nbsp;Florian B. Reyda ,&nbsp;Wenxiang Li ,&nbsp;Hudson A. Pinto ,&nbsp;Sean A. Locke","doi":"10.1016/j.ijpara.2024.11.002","DOIUrl":"10.1016/j.ijpara.2024.11.002","url":null,"abstract":"<div><div>The Azygiidae Looss, 1899 is a family of digeneans with a Holarctic distribution in which members of some genera mature in marine elasmobranchs while others occur only in freshwater teleosts. Some have questioned whether the marine genus <em>Otodistomum</em> Stafford, 1904 indeed belongs to the same family as the freshwater azygiid genera, namely <em>Azygia</em> Looss, 1899, <em>Proterometra</em> Horsfall, 1933, and <em>Leuceruthrus</em> Marshall and Gilbert, 1905. We present phylogenetic analyses based on mitochondrial genomes, rDNA operons, and partial cytochrome <em>c</em> oxidase I (<em>Cox1</em>) sequences from North American and Asian species that support the monophyly of Azygiidae, and placement of Azygioidea in the suborder Hemiurata, in contrast to recently published mitochondrial genome phylogenies. All phylogenies indicate that <em>Azygia</em> includes <em>Leuceruthrus</em>, which we therefore propose to be a junior synonym, together with suppression of the Leuceruthrinae. The status of <em>Proterometra</em> was equivocal, with support in some but not all analyses of 28S, but not in other markers. We describe a new species of <em>Azygia</em> from northeastern North America. Our results confirm the morphological variability of adults in <em>Azygia</em>, with worm size positively correlated with host size in <em>Azygia angusticauda</em>. Phylogenies suggest a marine origin for the Azygiidae, and a Palearctic origin for freshwater azygiids, with a single trans-Atlantic radiation to the Nearctic.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 103-115"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of five volatile organic compounds that trigger hygienic and recapping behaviours in the honey bee (Apis mellifera).","authors":"Amélie Noël, Charlène Dumas, Emilien Rottier, Dominique Beslay, Guy Costagliola, Christian Ginies, Florence Nicolè, Yves Le Conte, Fanny Mondet","doi":"10.1016/j.ijpara.2025.01.009","DOIUrl":"https://doi.org/10.1016/j.ijpara.2025.01.009","url":null,"abstract":"<p><p>Varroa destructor, the main parasite of the honey bee (Apis mellifera), is having a devastating effect on beekeeping worldwide. The development of resistance traits in some colonies, linked with Varroa-sensitive hygiene (VSH) and recapping (REC) behaviours, provide an ideal avenue for long-term sustainable control of the parasite. The most important step in these behaviours is the detection of parasitized brood cells. Several semiochemicals released from Varroa-infested brood cells, targeted by VSH behaviour, trigger this behaviour. Most of these compounds are not very volatile. In the current work, we focus on the study of volatile organic compound (VOC) emissions from Varroa-infested cells. This study describes the emission of nine VOCs characteristic of Varroa parasitism, of which five could be identified and triggered hygienic and recapping behaviours. These five compounds were also tested with compounds already described in the literature, in relation to the volatile nature of the compounds. Using solutions containing 1 - 15 compounds, we looked at the cleaning and recapping behaviours of the workers. Behavioural results highlight the importance of the VOCs found in this study in the detection, opening and recapping of brood cells, while low volatile compounds seem to play a particularly key role in the sacrifice of pupae. Similar to the Varroa parasitization-specific (VPS) compounds, including the tetracosyl acetate alone, the cleaning of brood cells triggered by one of the compounds identified in this study, n-tetradecane, appears to be linked to the colony's ability to carry out VSH behaviour. This study opens new perspectives in the understanding of resistance behaviour of honey bees against their main parasite Varroa destructor.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143122077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro culture of the parasitic stage larvae of hematophagous parasitic nematode Haemonchus contortus.","authors":"Lu Liu, Zongshan Zhang, Fuqiang Liu, Hui Liu, Lisha Ye, Feng Liu, Nishith Gupta, Chunqun Wang, Min Hu","doi":"10.1016/j.ijpara.2025.01.007","DOIUrl":"10.1016/j.ijpara.2025.01.007","url":null,"abstract":"<p><p>Current research on common parasitic nematodes is limited because their infective stages cannot be propagated in vitro. Here, we report a culture system for developing L4s of Haemonchus contortus, a blood-feeding nematode of ruminants. Our results demonstrated that a proportionate mixture of NCTC-109 to Luria-Bertini (1:2) media promoted the formation of early L4s and then into late L4s upon inclusion of 12.5% (v/v) defibrinated blood, albeit with a decline in survival. Adding antioxidants (0.3 mg/mL of L-glutathione or 200 nmol of vitamin C) improved survival of L4s, with approximately 90% developing to late L4s by 22 days. These L4s showed parallel morphological features (such as digestive and reproduction systems) compared with in vivo L4s at day 7 (following challenge infection), although with delayed development. Our work optimized the in vitro culture system for L4s while providing an important platform for in-depth molecular research on Haemonchus and other related parasitic nematodes.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143028432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}