International journal for parasitology最新文献_第7页

A study of the epidemiology of Anoplocephala perfoliata infection in horses and the oribatid mite vector in southern England 英格兰南部马中马头虫感染及甲螨病媒的流行病学研究。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-12-01 Epub Date: 2025-09-20 DOI: 10.1016/j.ijpara.2025.09.003

Hannah Wickenden , Kirsty L. Lightbody , Natalia Peczak , Kim B. Stevens , Danica Pollard , Damer P. Blake , Corrine J. Austin , Jacqueline B. Matthews , Mark T. Fox

Anoplocephala perfoliata is the most common equine tapeworm infection. This parasite is found at the small/large intestinal junction and has been associated with colic. The cestode has an indirect lifecycle involving oribatid mite intermediate hosts, though little is known of its epidemiology. This study aimed to monitor seasonal fluctuations in pasture oribatid mite numbers and the presence of Anoplocephala spp. DNA in mite samples collected from three equine premises in the UK. Exposure to infection in resident horses was assessed by measuring tapeworm-specific salivary antibodies. The data were analysed with management information to identify factors associated with the occurrence of (i) pasture samples containing different oribatid families, (ii) mite samples containing Anoplocephala spp. DNA, and (iii) a borderline or moderate high saliva score in the ELISA. Each yard was visited every four weeks (June 2016-August 2017) when three pastures were vacuum-sampled for mites. Three, one metre-square tetrads and grass surrounding 10 faecal pats were sampled per pasture. Mites collected were counted, identified to family level and pooled by family for Anoplocephala spp. DNA screening by polymerase chain reaction (PCR). Saliva samples were screened for A. perfoliata antibodies using the EquiSal® Tapeworm test in 10–23 horses at each yard every 2–3 weeks. Mixed-effects regression models were used to identify risk factors for each of the three outcomes. The results indicated that oribatid mite families not identified previously could act as intermediate hosts for Anoplocephala spp., and established that whilst oribatid mites might be found on pasture year-round, Damaeolidae and Oribatidae were 81 % (p = 0.005) and 64 % (p = 0.004) less likely to be detected in winter than in summer. Tapeworm-infected mites were more likely to be detected from March to September when more mites were recovered from paddocks, whilst saliva antibody test-positive horses were least likely to occur in autumn. Horses that grazed for half a day compared to those that grazed for full days were less likely to be positive in the saliva test. The findings yielded new insights into the epidemiology of equine tapeworm and its intermediate host in the UK, and contribute valuable information to support evidence-based control programmes for this parasite.

马头绦虫是最常见的马绦虫感染。这种寄生虫在小肠/大肠交界处发现，并与绞痛有关。该寄生虫有一个间接的生命周期，涉及甲螨中间宿主，尽管对其流行病学知之甚少。本研究旨在监测牧场甲螨数量的季节性波动和在英国三个马场采集的螨样本中存在的牛头蝇类DNA。通过测量绦虫特异性唾液抗体来评估驻地马暴露于感染。将数据与管理信息进行分析，以确定(i)牧场样本中含有不同的甲虫科，（ii）螨样本中含有牛头蝇的DNA，以及（iii） ELISA唾液评分处于边缘或中高水平的因素。每四周（2016年6月至2017年8月）对每个院子进行一次访问，并对三个牧场进行真空取样以检测螨虫。每个牧场取样3个，1平方米的四分体和周围10个粪便块的草。对采集到的螨进行计数，按科级鉴定，按科合并，采用聚合酶链反应（PCR）进行DNA筛选。采用EquiSal®绦虫试验对10-23匹马的唾液样本进行perfoliata抗体筛选，每2-3周进行一次。使用混合效应回归模型来确定三个结果的危险因素。结果表明，未鉴定的甲螨科可作为牛头蝇的中间寄主；牧场全年均可发现甲螨，但冬季发现达螨科和甲螨科的比例分别为81% （p=0.005）和64% （p=0.004）。绦虫感染的螨在3月至9月更容易被检测到，此时从围场中回收的螨较多，而唾液抗体测试阳性的马在秋季最不可能出现。与那些吃了一整天草的马相比，吃了半天草的马在唾液测试中呈阳性的可能性更小。这些发现为英国马绦虫及其中间宿主的流行病学提供了新的见解，并为支持这种寄生虫的循证控制规划提供了有价值的信息。

{"title":"A study of the epidemiology of Anoplocephala perfoliata infection in horses and the oribatid mite vector in southern England","authors":"Hannah Wickenden , Kirsty L. Lightbody , Natalia Peczak , Kim B. Stevens , Danica Pollard , Damer P. Blake , Corrine J. Austin , Jacqueline B. Matthews , Mark T. Fox","doi":"10.1016/j.ijpara.2025.09.003","DOIUrl":"10.1016/j.ijpara.2025.09.003","url":null,"abstract":"<div><div><em>Anoplocephala perfoliata</em> is the most common equine tapeworm infection. This parasite is found at the small/large intestinal junction and has been associated with colic. The cestode has an indirect lifecycle involving oribatid mite intermediate hosts, though little is known of its epidemiology. This study aimed to monitor seasonal fluctuations in pasture oribatid mite numbers and the presence of <em>Anoplocephala</em> spp. DNA in mite samples collected from three equine premises in the UK. Exposure to infection in resident horses was assessed by measuring tapeworm-specific salivary antibodies. The data were analysed with management information to identify factors associated with the occurrence of (i) pasture samples containing different oribatid families, (ii) mite samples containing <em>Anoplocephala</em> spp. DNA, and (iii) a borderline or moderate high saliva score in the ELISA. Each yard was visited every four weeks (June 2016-August 2017) when three pastures were vacuum-sampled for mites. Three, one metre-square tetrads and grass surrounding 10 faecal pats were sampled per pasture. Mites collected were counted, identified to family level and pooled by family for <em>Anoplocephala</em> spp. DNA screening by polymerase chain reaction (PCR). Saliva samples were screened for <em>A. perfoliata</em> antibodies using the EquiSal® Tapeworm test in 10–23 horses at each yard every 2–3 weeks. Mixed-effects regression models were used to identify risk factors for each of the three outcomes. The results indicated that oribatid mite families not identified previously could act as intermediate hosts for <em>Anoplocephala</em> spp., and established that whilst oribatid mites might be found on pasture year-round, Damaeolidae and Oribatidae were 81 % (<em>p</em> = 0.005) and 64 % (<em>p</em> = 0.004) less likely to be detected in winter than in summer. Tapeworm-infected mites were more likely to be detected from March to September when more mites were recovered from paddocks, whilst saliva antibody test-positive horses were least likely to occur in autumn. Horses that grazed for half a day compared to those that grazed for full days were less likely to be positive in the saliva test. The findings yielded new insights into the epidemiology of equine tapeworm and its intermediate host in the UK, and contribute valuable information to support evidence-based control programmes for this parasite.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 14","pages":"Pages 783-794"},"PeriodicalIF":3.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145124730","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}

引用次数: 0

Testing the host specificity hypothesis: delimitation of Gyrodactylus species infecting fishes of the family Profundulidae across their distribution range 检验宿主特异性假说：在分布范围内感染深孔鱼科鱼类的旋毛虫物种的划分。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-12-01 Epub Date: 2025-08-11 DOI: 10.1016/j.ijpara.2025.08.001

Miguel Calixto-Rojas , Miguel Rubio-Godoy , Ismael Guzmán-Valdivieso , Juan J. Barrios-Gutiérrez , Carlos D. Pinacho-Pinacho

Host specificity, a trait describing how many different hosts a parasite can infect, ranges from strict specialists for parasites associated to a single host species, to generalists for those able to infect several host species, which may even be phylogenetically unrelated. Monogenea are generally considered to be specialist parasites, but this appreciation may be an artifact arising from biased or limited sampling. Here, we evaluate host specificity of species of Gyrodactylus infecting fishes of the family Profundulidae collected in southern Mexico and, crucially, encompassing the whole distribution range of seven profundulid species. We used several molecular species delimitation methods to identify parasite lineages, which consistently recovered six species, four previously known and two new species, which we describe here. Gyrodactylid species infected from one to seven profundulid fish species, spanning the whole range of recognized host specificity associations, from strict specialists to generalists. No clear pattern could be discerned in the host-parasite associations we analysed (phylogenetic, host, geographical), suggesting that the ecological and evolutionary history of Gyrodactylus transcends that of their hosts – and one can envisage that with progressively more in-depth studies, it will be increasingly more difficult to speak of “general” patterns within large and complex groups of parasites, like the genus Gyrodactylus (Monogenea).

宿主特异性是一种描述寄生虫可以感染多少不同宿主的特征，其范围从与单一宿主物种相关的寄生虫的严格专家到能够感染几种宿主物种的通才，这些宿主物种甚至可能在系统发育上无关。单系通常被认为是专门的寄生虫，但这种评价可能是由于有偏见或有限的抽样而产生的假象。在这里，我们评估了Gyrodactylus感染在墨西哥南部收集的prounduldae科鱼类的物种的宿主特异性，并且至关重要的是，涵盖了7种prounduldae物种的整个分布范围。我们使用了几种分子物种划分方法来鉴定寄生虫谱系，一致地恢复了6种，4种以前已知的和2种新的，我们在这里描述。从一种到七种深海鱼类，从严格的专家到通才，跨越了宿主特异性关联的整个范围。在我们分析的宿主-寄生虫关联（系统发育，宿主，地理）中没有明确的模式，这表明Gyrodactylus的生态和进化历史超越了它们的宿主-人们可以设想，随着研究的逐步深入，在大型和复杂的寄生虫群体中谈论“一般”模式将越来越困难，比如Gyrodactylus属（单属）。

{"title":"Testing the host specificity hypothesis: delimitation of Gyrodactylus species infecting fishes of the family Profundulidae across their distribution range","authors":"Miguel Calixto-Rojas , Miguel Rubio-Godoy , Ismael Guzmán-Valdivieso , Juan J. Barrios-Gutiérrez , Carlos D. Pinacho-Pinacho","doi":"10.1016/j.ijpara.2025.08.001","DOIUrl":"10.1016/j.ijpara.2025.08.001","url":null,"abstract":"<div><div>Host specificity, a trait describing how many different hosts a parasite can infect, ranges from strict specialists for parasites associated to a single host species, to generalists for those able to infect several host species, which may even be phylogenetically unrelated. Monogenea are generally considered to be specialist parasites, but this appreciation may be an artifact arising from biased or limited sampling. Here, we evaluate host specificity of species of <em>Gyrodactylus</em> infecting fishes of the family Profundulidae collected in southern Mexico and, crucially, encompassing the whole distribution range of seven profundulid species. We used several molecular species delimitation methods to identify parasite lineages, which consistently recovered six species, four previously known and two new species, which we describe here. Gyrodactylid species infected from one to seven profundulid fish species, spanning the whole range of recognized host specificity associations, from strict specialists to generalists. No clear pattern could be discerned in the host-parasite associations we analysed (phylogenetic, host, geographical), suggesting that the ecological and evolutionary history of <em>Gyrodactylus</em> transcends that of their hosts – and one can envisage that with progressively more in-depth studies, it will be increasingly more difficult to speak of “general” patterns within large and complex groups of parasites, like the genus <em>Gyrodactylus</em> (Monogenea).</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 14","pages":"Pages 805-819"},"PeriodicalIF":3.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144845893","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}

引用次数: 0

When can multiple parasites with complex life cycles coexist under conflicts of host manipulation? 在宿主操纵的冲突下，具有复杂生命周期的多种寄生虫何时可以共存？

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-12-01 Epub Date: 2025-09-02 DOI: 10.1016/j.ijpara.2025.08.012

Chih-Wei Wang , Hsuan-Wien Chen , Takuya Sato , Takefumi Nakazawa

Parasites are diverse and play crucial roles in ecosystems, yet mechanisms underlying their diversity remain poorly understood. Many parasites have complex life cycles, manipulating their hosts to facilitate transition through inter-host trophic interactions. When multiple parasites share a common intermediate host but transition to different definitive hosts, they face two conflicts in host manipulation strategies. First, host manipulation may increase predation by non-host predators, leading to “dead-ends.” Second, interactions among parasites may complicate host manipulation in a co-infected intermediate host. To explore how host-manipulating parasites compete and coexist under these conflicts, we developed a mathematical model describing population dynamics of two parasites, one intermediate host (prey), and two definitive hosts (predators). The competitive exclusion principle predicts that the two definitive hosts (and thus their parasites) cannot coexist due to competition for the intermediate host. However, our results show that host-manipulating parasites can alter this outcome. We identified three conditions that promote parasite coexistence: (i) the parasite infecting the competitively inferior predator is more prone to dead-ends as a result of adopting a target-generic host manipulation strategy, (ii) co-infected intermediate hosts are manipulated so that predation by the competitively superior predator decreases, whereas predation by the competitively inferior predator increases, and (iii) host–parasite community dynamics exhibit limited fluctuations. Future studies are encouraged to evaluate the likelihood that these conditions are met. Furthermore, we found that alternative states can emerge across a broad parameter space, suggesting potential regime shifts in their community composition. These findings provide novel insights into the mechanisms underlying parasite diversity and its fragility, laying the groundwork for future research on more complex scenarios.

寄生虫种类繁多，在生态系统中发挥着至关重要的作用，但人们对其多样性背后的机制知之甚少。许多寄生虫具有复杂的生命周期，通过宿主间的营养相互作用操纵宿主以促进过渡。当多种寄生虫共享一个共同的中间宿主，但过渡到不同的最终宿主时，它们在宿主操作策略上面临两种冲突。首先，宿主操纵可能会增加非宿主捕食者的捕食，导致“死胡同”。其次，寄生虫之间的相互作用可能使共感染中间宿主的宿主操作复杂化。为了探索在这些冲突中操纵宿主的寄生虫是如何竞争和共存的，我们建立了一个描述两种寄生虫，一个中间宿主（猎物）和两个最终宿主（捕食者）的种群动态的数学模型。竞争排斥原理预测，由于对中间宿主的竞争，两个最终宿主（以及它们的寄生虫）不能共存。然而，我们的研究结果表明，操纵宿主的寄生虫可以改变这一结果。我们确定了促进寄生虫共存的三个条件：(i)由于采用目标通用宿主操纵策略，感染竞争性劣势捕食者的寄生虫更容易陷入死胡同；（ii）共同感染的中间宿主被操纵，从而竞争性优势捕食者的捕食减少，而竞争性劣势捕食者的捕食增加；（iii）宿主-寄生虫群落动态表现出有限的波动。鼓励未来的研究评估满足这些条件的可能性。此外，我们发现替代状态可以在广泛的参数空间中出现，这表明它们的群落组成可能发生变化。这些发现为寄生虫多样性及其脆弱性的机制提供了新的见解，为未来更复杂情况的研究奠定了基础。

{"title":"When can multiple parasites with complex life cycles coexist under conflicts of host manipulation?","authors":"Chih-Wei Wang , Hsuan-Wien Chen , Takuya Sato , Takefumi Nakazawa","doi":"10.1016/j.ijpara.2025.08.012","DOIUrl":"10.1016/j.ijpara.2025.08.012","url":null,"abstract":"<div><div>Parasites are diverse and play crucial roles in ecosystems, yet mechanisms underlying their diversity remain poorly understood. Many parasites have complex life cycles, manipulating their hosts to facilitate transition through inter-host trophic interactions. When multiple parasites share a common intermediate host but transition to different definitive hosts, they face two conflicts in host manipulation strategies. First, host manipulation may increase predation by non-host predators, leading to “dead-ends.” Second, interactions among parasites may complicate host manipulation in a co-infected intermediate host. To explore how host-manipulating parasites compete and coexist under these conflicts, we developed a mathematical model describing population dynamics of two parasites, one intermediate host (prey), and two definitive hosts (predators). The competitive exclusion principle predicts that the two definitive hosts (and thus their parasites) cannot coexist due to competition for the intermediate host. However, our results show that host-manipulating parasites can alter this outcome. We identified three conditions that promote parasite coexistence: (i) the parasite infecting the competitively inferior predator is more prone to dead-ends as a result of adopting a target-generic host manipulation strategy, (ii) co-infected intermediate hosts are manipulated so that predation by the competitively superior predator decreases, whereas predation by the competitively inferior predator increases, and (iii) host–parasite community dynamics exhibit limited fluctuations. Future studies are encouraged to evaluate the likelihood that these conditions are met. Furthermore, we found that alternative states can emerge across a broad parameter space, suggesting potential regime shifts in their community composition. These findings provide novel insights into the mechanisms underlying parasite diversity and its fragility, laying the groundwork for future research on more complex scenarios.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 14","pages":"Pages 771-781"},"PeriodicalIF":3.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145000459","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}

引用次数: 0

Genetically tractable rodent models for Cryptosporidium hominis and C. parvum infections: identifying differences in infection sites between host species 人隐孢子虫和小隐孢子虫感染的遗传易感啮齿动物模型：识别宿主物种之间感染部位的差异。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-12-01 Epub Date: 2025-08-14 DOI: 10.1016/j.ijpara.2025.08.003

Lianbei Sun , Wei He , Zuwei Yang , Yilin Wu , Jing Wang , Na Li , Yaqiong Guo , Rui Xu , Jiayu Li , Yaoyu Feng , Lihua Xiao

Cryptosporidiosis causes severe diarrhea in children and livestock. However, the absence of suitable rodent models has led to a lack of effective drugs and vaccines. In this study, genetically tractable rat and mouse models were developed for the two main causes of human cryptosporidiosis: Cryptosporidium hominis and C. parvum. Neonatal mice and rats were successfully infected with two nonhuman primate-adapted C. hominis isolates and one C. parvum IId isolate, resulting in high oocyst shedding. Using isolates tagged with fluorescent proteins and luciferases enabled the easy detection and quantification of oocyst shedding. Both Cryptosporidium species primarily infected the ileum, cecum, and colon of neonatal mice. In contrast, the parasites primarily colonized the duodenum and jejunum of neonatal rats. Both species responded to treatment with a lysyl-tRNA synthetase inhibitor in the rat model. Developing tractable animal models with different infection sites will allow for comparative studies of the biology and immunity of major human-pathogenic Cryptosporidium species, as well as the evaluation of potential drugs and vaccines.

隐孢子虫病导致儿童和牲畜严重腹泻。然而，由于缺乏合适的啮齿动物模型，导致缺乏有效的药物和疫苗。在这项研究中，遗传易感的大鼠和小鼠模型建立了人类隐孢子虫病的两个主要原因：人隐孢子虫和小隐孢子虫。新生小鼠和大鼠成功感染了两株非人灵长类适应的人猿C.菌株和一株小C.菌株，导致卵囊大量脱落。使用荧光蛋白和荧光素酶标记的分离物可以方便地检测和定量卵囊脱落。这两种隐孢子虫主要感染新生小鼠的回肠、盲肠和结肠。相比之下，寄生虫主要定植于新生大鼠的十二指肠和空肠。在大鼠模型中，这两个物种都对赖氨酸- trna合成酶抑制剂治疗有反应。开发具有不同感染部位的易处理的动物模型将允许对主要人类致病性隐孢子虫物种的生物学和免疫力进行比较研究，以及评估潜在的药物和疫苗。

{"title":"Genetically tractable rodent models for Cryptosporidium hominis and C. parvum infections: identifying differences in infection sites between host species","authors":"Lianbei Sun , Wei He , Zuwei Yang , Yilin Wu , Jing Wang , Na Li , Yaqiong Guo , Rui Xu , Jiayu Li , Yaoyu Feng , Lihua Xiao","doi":"10.1016/j.ijpara.2025.08.003","DOIUrl":"10.1016/j.ijpara.2025.08.003","url":null,"abstract":"<div><div>Cryptosporidiosis causes severe diarrhea in children and livestock. However, the absence of suitable rodent models has led to a lack of effective drugs and vaccines. In this study, genetically tractable rat and mouse models were developed for the two main causes of human cryptosporidiosis: <em>Cryptosporidium hominis</em> and <em>C. parvum</em>. Neonatal mice and rats were successfully infected with two nonhuman primate-adapted <em>C. hominis</em> isolates and one <em>C. parvum</em> IId isolate, resulting in high oocyst shedding. Using isolates tagged with fluorescent proteins and luciferases enabled the easy detection and quantification of oocyst shedding. Both <em>Cryptosporidium</em> species primarily infected the ileum, cecum, and colon of neonatal mice. In contrast, the parasites primarily colonized the duodenum and jejunum of neonatal rats. Both species responded to treatment with a lysyl-tRNA synthetase inhibitor in the rat model. Developing tractable animal models with different infection sites will allow for comparative studies of the biology and immunity of major human-pathogenic <em>Cryptosporidium</em> species, as well as the evaluation of potential drugs and vaccines.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 14","pages":"Pages 795-804"},"PeriodicalIF":3.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144862146","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}

引用次数: 0

Systematics and phylogeny of Chalcinotrematinae (Digenea: Haploporidae): Erection of a new genus and description of two new species from South America through integrated analyses. Chalcinotrematinae的系统学和系统发育（di亚纲：单孔虫科）：一新属的建立和两新种的综合分析。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-28 DOI: 10.1016/j.ijpara.2025.11.005

Camila Pantoja, Olena Kudlai, Maarten P M Vanhove, Rodney A Bray, José L Luque, Nikol Kmentová, Tomáš Scholz

The subfamily Chalcinotrematinae (Haploporidae) comprises an understudied group of digenean parasites infecting freshwater and brackish water fishes across the Americas, Africa, and Asia. Its systematics has rarely been investigated using molecular data, with DNA sequences available for only a few species representing two of the six recognised genera. We collected chalcinotrematine trematodes from freshwater fishes in the Jari River, Amazon Basin, Brazil, and in Misiones, Argentina. Specimens from Brazil were characterised through an integrative approach combining morphological examination with molecular data (partial 28S and ITS2 rDNA sequences), whereas those from Argentina were analysed morphologically. As a result, we describe two new species from Brazil: Chalcinotrema arleneae sp. nov. from Leporinus friderici and Laemolyta proxima, and Unicoelium gerardoi sp. nov. from Hypostomus plecostomus. This study provides the first molecular data for both Chalcinotrema and Unicoelium, expanding the phylogenetic framework of Chalcinotrematinae. Paralecithobotrys brasiliensis is recorded from Argentina in Megaleporinus obtusidens, extending its geographical range. We reassessed the generic limits of Saccocoelioides, the most species-rich genus within the subfamily. Based on combined morphological, molecular, host, and distributional evidence, we propose taxonomic revisions, establishing Neosaccocoelioides gen. nov. for several South American species formerly assigned to Saccocoelioides: N. antonioi comb. nov., N. bacilliformis comb. nov., N. elongatus comb. nov., N. magnus comb. nov., N. miguelmontesi comb. nov. (type species), and N. szidati comb. nov. Additionally, N. platense comb. nov., previously placed in Chalcinotrema, is transferred to the new genus. Saccocoelioides chilkaensis and S. lizae are considered species inquirendae; and S. guaporense is considered incertae sedis. These findings refine chalcinotrematine relationships and highlight the need for expanded molecular datasets to resolve systematic and biogeographical uncertainties.

Chalcinotrematinae亚科（Haploporidae）是一种未经充分研究的感染美洲、非洲和亚洲淡水和咸淡水鱼类的digenean寄生虫。它的系统学很少使用分子数据进行研究，只有代表六个公认属中的两个的少数物种的DNA序列。我们从巴西亚马逊河流域的Jari河和阿根廷米西奥内斯的淡水鱼中采集了查尔辛虫碱吸虫。来自巴西的标本通过结合形态学检查和分子数据（部分28S和ITS2 rDNA序列）的综合方法进行表征，而来自阿根廷的标本则进行形态学分析。结果发现了两个新种：来自friderici Leporinus和Laemolyta proxima的Chalcinotrema arleneae sp. 11和来自Hypostomus plecostomus的gerardoi sp. 11。本研究首次提供了Chalcinotrema和Unicoelium的分子数据，扩展了chalcinotrematae的系统发育框架。在阿根廷的Megaleporinus obtusidens中发现了brasiliensis，扩大了其地理范围。我们重新评估了该亚科中物种最丰富的属Saccocoelioides的属界。基于形态、分子、寄主和分布的综合证据，我们提出了分类修正，将几个原归属于Saccocoelioides: N. antonioi comb的南美物种建立为Neosaccocoelioides gen. 11。11月，芽孢杆菌梳。11月，N.长形梳。11月，n.m magnus梳子。11月，n.m iguelmontesi梳子。11 .（模式种），和N. szidati梳子。11 .此外，N. platense梳子。十一月，以前放置在Chalcinotrema，被转移到新的属。Saccocoelioides chilkaensis和s.l izae被认为是询问科的种；而瓜梨花则被认为是不可靠的。这些发现完善了Chalcinotrematinae的关系，并强调了扩大分子数据集以解决系统和生物地理不确定性的必要性。

{"title":"Systematics and phylogeny of Chalcinotrematinae (Digenea: Haploporidae): Erection of a new genus and description of two new species from South America through integrated analyses.","authors":"Camila Pantoja, Olena Kudlai, Maarten P M Vanhove, Rodney A Bray, José L Luque, Nikol Kmentová, Tomáš Scholz","doi":"10.1016/j.ijpara.2025.11.005","DOIUrl":"10.1016/j.ijpara.2025.11.005","url":null,"abstract":"<p><p>The subfamily Chalcinotrematinae (Haploporidae) comprises an understudied group of digenean parasites infecting freshwater and brackish water fishes across the Americas, Africa, and Asia. Its systematics has rarely been investigated using molecular data, with DNA sequences available for only a few species representing two of the six recognised genera. We collected chalcinotrematine trematodes from freshwater fishes in the Jari River, Amazon Basin, Brazil, and in Misiones, Argentina. Specimens from Brazil were characterised through an integrative approach combining morphological examination with molecular data (partial 28S and ITS2 rDNA sequences), whereas those from Argentina were analysed morphologically. As a result, we describe two new species from Brazil: Chalcinotrema arleneae sp. nov. from Leporinus friderici and Laemolyta proxima, and Unicoelium gerardoi sp. nov. from Hypostomus plecostomus. This study provides the first molecular data for both Chalcinotrema and Unicoelium, expanding the phylogenetic framework of Chalcinotrematinae. Paralecithobotrys brasiliensis is recorded from Argentina in Megaleporinus obtusidens, extending its geographical range. We reassessed the generic limits of Saccocoelioides, the most species-rich genus within the subfamily. Based on combined morphological, molecular, host, and distributional evidence, we propose taxonomic revisions, establishing Neosaccocoelioides gen. nov. for several South American species formerly assigned to Saccocoelioides: N. antonioi comb. nov., N. bacilliformis comb. nov., N. elongatus comb. nov., N. magnus comb. nov., N. miguelmontesi comb. nov. (type species), and N. szidati comb. nov. Additionally, N. platense comb. nov., previously placed in Chalcinotrema, is transferred to the new genus. Saccocoelioides chilkaensis and S. lizae are considered species inquirendae; and S. guaporense is considered incertae sedis. These findings refine chalcinotrematine relationships and highlight the need for expanded molecular datasets to resolve systematic and biogeographical uncertainties.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":"104753"},"PeriodicalIF":3.2,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145633127","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}

引用次数: 0

Ten simple rules for implementing deep amplicon sequencing in parasitology. 在寄生虫学中实施深度扩增子测序的十个简单规则。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-21 DOI: 10.1016/j.ijpara.2025.11.003

Jan Šlapeta, Jürgen Krücken, Alicia Rojas, Alex Chambers, Lynsey A Melville, María Martínez-Valladares, Candela Canton, Emily K Francis, Osama Zahid, Ana Cláudia A Albuquerque, Dave J Bartley, Cesar C Bassetto, Orla Byrne, Vito Colella, Livio M Costa-Junior, Stephen R Doyle, Mike Evans, Abdul Ghafar, Pablo Godoy, Naoki Hayashi, Mohamed A Helal, Lucas G Huggins, Abdul Jabbar, Rhys A Jones, Benedict E Karani, Juan Pedro Liron, Laura Maté, Amanda McEvoy, Khalid M Mohammedsalih, Grace Mulcahy, Martin K Nielsen, Barbora Pafčo, Laura E Peachey, Joby Robleto-Quesada, Georg von Samson-Himmelstjerna, Lucas C de Sousa-Paula, John S Gilleard

Deep amplicon sequencing is transforming parasitology by enabling high-throughput profiling of parasite communities and detection of resistance-associated genetic variants. Despite its growing adoption, many researchers face challenges in implementation, and its full potential is often hindered by challenges in experimental design, including marker selection, data analysis and reproducibility. This article presents ten simple rules for applying deep amplicon sequencing in parasitology, developed through expert consensus at a deep amplicon sequencing symposium during the 2025 World Association for the Advancement of Veterinary Parasitology conference. These rules cover essential aspects from formulating research questions and choosing appropriate markers to managing data workflows and contributing to reference databases. We highlight the importance of integrating deep amplicon sequencing with traditional parasitological methods, ensuring transparent reporting and investing in capacity building. Whether you are new to deep amplicon sequencing or seeking to improve your current practices, these guidelines offer practical advice to enhance the robustness, reproducibility, and impact of your research. By adopting these principles, parasitologists can contribute to, and advance, a more reliable and collaborative scientific landscape.

深度扩增子测序通过实现寄生虫群落的高通量分析和检测耐药性相关的遗传变异，正在改变寄生虫学。尽管越来越多的人采用它，但许多研究人员在实施过程中面临挑战，而且它的全部潜力往往受到实验设计方面的挑战的阻碍，包括标记选择、数据分析和可重复性。本文介绍了在寄生虫学中应用深度扩增子测序的十个简单规则，这些规则是在2025年世界兽医寄生虫学促进协会会议期间的深度扩增子测序研讨会上通过专家共识制定的。这些规则涵盖了从制定研究问题和选择适当的标记到管理数据工作流程和提供参考数据库的基本方面。我们强调将深度扩增子测序与传统寄生虫学方法相结合的重要性，确保报告透明，并投资于能力建设。无论您是深度扩增子测序的新手还是寻求改进您当前的实践，这些指南都提供了实用的建议，以增强您的研究的稳健性，可重复性和影响。通过采用这些原则，寄生虫学家可以为更可靠和合作的科学景观做出贡献并推动其发展。

{"title":"Ten simple rules for implementing deep amplicon sequencing in parasitology.","authors":"Jan Šlapeta, Jürgen Krücken, Alicia Rojas, Alex Chambers, Lynsey A Melville, María Martínez-Valladares, Candela Canton, Emily K Francis, Osama Zahid, Ana Cláudia A Albuquerque, Dave J Bartley, Cesar C Bassetto, Orla Byrne, Vito Colella, Livio M Costa-Junior, Stephen R Doyle, Mike Evans, Abdul Ghafar, Pablo Godoy, Naoki Hayashi, Mohamed A Helal, Lucas G Huggins, Abdul Jabbar, Rhys A Jones, Benedict E Karani, Juan Pedro Liron, Laura Maté, Amanda McEvoy, Khalid M Mohammedsalih, Grace Mulcahy, Martin K Nielsen, Barbora Pafčo, Laura E Peachey, Joby Robleto-Quesada, Georg von Samson-Himmelstjerna, Lucas C de Sousa-Paula, John S Gilleard","doi":"10.1016/j.ijpara.2025.11.003","DOIUrl":"10.1016/j.ijpara.2025.11.003","url":null,"abstract":"<p><p>Deep amplicon sequencing is transforming parasitology by enabling high-throughput profiling of parasite communities and detection of resistance-associated genetic variants. Despite its growing adoption, many researchers face challenges in implementation, and its full potential is often hindered by challenges in experimental design, including marker selection, data analysis and reproducibility. This article presents ten simple rules for applying deep amplicon sequencing in parasitology, developed through expert consensus at a deep amplicon sequencing symposium during the 2025 World Association for the Advancement of Veterinary Parasitology conference. These rules cover essential aspects from formulating research questions and choosing appropriate markers to managing data workflows and contributing to reference databases. We highlight the importance of integrating deep amplicon sequencing with traditional parasitological methods, ensuring transparent reporting and investing in capacity building. Whether you are new to deep amplicon sequencing or seeking to improve your current practices, these guidelines offer practical advice to enhance the robustness, reproducibility, and impact of your research. By adopting these principles, parasitologists can contribute to, and advance, a more reliable and collaborative scientific landscape.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145586917","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}

引用次数: 0

Evaluation of a lateral flow test to diagnose liver fluke in cattle and sheep. 牛羊肝吸虫侧流试验诊断的评价。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-20 DOI: 10.1016/j.ijpara.2025.11.004

Tessa R Walsh, Joseph W Angell, Andrew Bentham, Eleanor Bentley, Helen Clough, John Graham-Brown, Alison Howell, Sonja Steinke, Alison Wakeham, Diana J L Williams

Fasciola hepatica (the liver fluke) is an important parasite of cattle and sheep globally. Current diagnostic tests are laboratory based, which involve costs for sample collection and time taken for results to be returned. This can discourage farmers from engaging with the industry message to test before treating. Treatment in the absence of a diagnosis can contribute to the development of resistance to anthelmintics. We have developed a lateral flow test (LFT) to detect antibodies to fluke in whole blood, which can be used on-farm to detect exposure in cattle and sheep within 10 min. LFT performance was evaluated though on-farm trials sampling 10 sheep on 24 farms, and where possible, up to 10 cattle. Results were compared to those obtained with an in-house antibody detection ELISA. Linear regression analysis showed a positive correlation between LFT and ELISA results. Bayesian analysis assuming no gold standard indicated that the LFT had a sensitivity (Se) of 77 % (95 % Credible Interval [CI] 61-91 %) and specificity (Sp) of 80 % (CI 70-89 %) in cattle and 67 % Se (CI 47-94 %) and 71 % Sp (CI 62-82 %) for sheep. Sub-setting for first season lambs gave 96 % Se (CI 85-100 %) and 74 % Sp (CI 65-84 %). A group interview with the farmers who participated in on-farm trials indicated they found the LFT easy to use and thought it would be a useful tool to guide treatment decisions. The LFT will enable farmers to better engage with fluke management on their farms and encourage appropriate use of anthelmintics.

肝片吸虫（肝吸虫）是全球牛羊的重要寄生虫。目前的诊断测试是基于实验室的，这涉及样品采集的费用和返回结果所需的时间。这可能会阻碍农民参与行业信息，在处理之前进行测试。在没有诊断的情况下进行治疗可能导致对驱虫药产生耐药性。我们开发了一种横向流动测试（LFT）来检测全血中的吸虫抗体，这种测试可以在农场上使用，在10分钟内检测出牛羊的感染情况。通过对24个农场的10只羊进行农场试验，并在可能的情况下对10只牛进行试验，评估了LFT的性能。将结果与内部抗体检测ELISA获得的结果进行比较。线性回归分析显示LFT与ELISA结果呈正相关。假设无金标准的贝叶斯分析表明，LFT对牛的灵敏度（Se）为77%(95%可信区间[CI] 61-91%)，特异性（Sp）为80% (CI 70-89%)，对羊的灵敏度（Se）为67% (CI 47-94%)，特异性（Sp）为71% （CI 62-82%）。第一季羔羊的亚设定硒含量为96% (CI 85-100%)，硒含量为74% （CI 65-84%）。对参加农场试验的农民进行的小组访谈表明，他们发现LFT易于使用，并认为它将是指导治疗决策的有用工具。LFT将使农民能够更好地参与农场的吸虫管理，并鼓励适当使用驱虫剂。

{"title":"Evaluation of a lateral flow test to diagnose liver fluke in cattle and sheep.","authors":"Tessa R Walsh, Joseph W Angell, Andrew Bentham, Eleanor Bentley, Helen Clough, John Graham-Brown, Alison Howell, Sonja Steinke, Alison Wakeham, Diana J L Williams","doi":"10.1016/j.ijpara.2025.11.004","DOIUrl":"10.1016/j.ijpara.2025.11.004","url":null,"abstract":"<p><p>Fasciola hepatica (the liver fluke) is an important parasite of cattle and sheep globally. Current diagnostic tests are laboratory based, which involve costs for sample collection and time taken for results to be returned. This can discourage farmers from engaging with the industry message to test before treating. Treatment in the absence of a diagnosis can contribute to the development of resistance to anthelmintics. We have developed a lateral flow test (LFT) to detect antibodies to fluke in whole blood, which can be used on-farm to detect exposure in cattle and sheep within 10 min. LFT performance was evaluated though on-farm trials sampling 10 sheep on 24 farms, and where possible, up to 10 cattle. Results were compared to those obtained with an in-house antibody detection ELISA. Linear regression analysis showed a positive correlation between LFT and ELISA results. Bayesian analysis assuming no gold standard indicated that the LFT had a sensitivity (Se) of 77 % (95 % Credible Interval [CI] 61-91 %) and specificity (Sp) of 80 % (CI 70-89 %) in cattle and 67 % Se (CI 47-94 %) and 71 % Sp (CI 62-82 %) for sheep. Sub-setting for first season lambs gave 96 % Se (CI 85-100 %) and 74 % Sp (CI 65-84 %). A group interview with the farmers who participated in on-farm trials indicated they found the LFT easy to use and thought it would be a useful tool to guide treatment decisions. The LFT will enable farmers to better engage with fluke management on their farms and encourage appropriate use of anthelmintics.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145581651","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}

引用次数: 0

Glycan remodelling of live adult Schistosoma mansoni worms by chemical inhibition of α-mannosidases. 通过α-甘露糖苷酶的化学抑制对曼氏血吸虫成虫的糖聚糖重塑研究。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-19 DOI: 10.1016/j.ijpara.2025.11.002

Eleonore B Kuhlemaijer, Tom Veldhuizen, Isabella A van Hulst, Tessa Liesker, Benjamin J Hulme, Josephine E Forde-Thomas, Gabriel Rinaldi, Karl F Hoffmann, Angela van Diepen, Cornelis H Hokke

Schistosomiasis is a neglected tropical disease affecting over 250 million people worldwide. Schistosoma parasites can survive in the human host for years due to their capability to evade and modulate host immune responses. Glycans and glycoproteins produced by schistosomes are thought to play an important role in shaping parasite-host interactions. In addition, N-linked glycans are vital post-translational protein modifications involved in fundamental cellular and developmental processes like protein folding and cell-cell interactions. In this study, we generated live Schistosoma mansoni adult worms with altered N-glycosylation using the α-mannosidase inhibitors kifunensine and swainsonine, compounds which restrict complex N-glycan processing thereby preventing complex N-glycan formation. We show that ex vivo cultured adult schistosomes display a stable N-glycosylation profile during two weeks of culture characterised by roughly one-third mannose and two-third complex glycans. Inhibition of α-mannosidases during culture resulted in a modified N-glycan profile over time: kifunensine-treated parasites were found to contain 76% mannose N-glycans, while swainsonine-treated parasites showed a strongly increased abundance of hybrid glycans and (fucosylated) mannose glycans. These observations are in line with the expected effect of the inhibitors on endoplasmic reticulum and Golgi α-mannosidases, respectively. Additionally, we examined the N-glycan composition of the worm tegument, a major parasitic structure found at the parasite-host interface. The tegument contained mainly complex N-glycans, often carrying the GalNAcβ1-4GlcNAc (LacdiNAc, LDN) motif, different from the rest of the schistosome body. Again, α-mannosidase inhibition changed the N-glycosylation profile of the tegument, similarly as observed for whole worms. No negative effects of any of the treatments on parasite motility or morphology were observed, indicating that the basic biology of the worms in culture was not affected by these N-glycosylation changes. Our results demonstrate the feasibility of creating a live glyco-remodelled parasite, setting the scene for studying functional parasite glycobiology and glycan-mediated effects in host-parasite interaction.

血吸虫病是一种被忽视的热带疾病，影响全世界2.5亿多人。由于具有逃避和调节宿主免疫反应的能力，血吸虫寄生虫可以在人类宿主体内存活数年。由血吸虫产生的聚糖和糖蛋白被认为在形成寄生虫-宿主相互作用中起重要作用。此外，n -链聚糖是重要的翻译后蛋白质修饰，参与基本的细胞和发育过程，如蛋白质折叠和细胞-细胞相互作用。在这项研究中，我们使用α-甘露糖苷酶抑制剂kifunenine和swainsonine生成了n -糖基化改变的曼氏血吸虫成虫，这些化合物限制了复杂n -聚糖的加工，从而阻止了复杂n -聚糖的形成。我们发现体外培养的成年血吸虫在两周的培养过程中表现出稳定的n -糖基化特征，其特征是大约三分之一的甘露糖和三分之二的复合聚糖。α-甘露糖苷酶在培养过程中的抑制作用导致n -聚糖谱随着时间的推移而改变：发现kifunenine处理的寄生虫含有76%的甘露糖n -聚糖，而苦马豆素处理的寄生虫显示出大量的杂交聚糖和（集中的）甘露糖聚糖。这些观察结果与预期抑制剂分别对内质网和高尔基α-甘露糖苷酶的作用一致。此外，我们研究了蠕虫被皮的n -聚糖组成，这是寄生虫-宿主界面上发现的主要寄生结构。被皮主要含有复杂的n -聚糖，通常携带GalNAcβ1-4GlcNAc （LacdiNAc， LDN）基序，与血吸虫体的其他部分不同。α-甘露糖苷酶抑制再次改变了被皮的n -糖基化谱，与整个蠕虫的观察结果相似。没有观察到任何处理对寄生虫运动和形态的负面影响，表明这些n -糖基化变化不影响培养中蠕虫的基本生物学。我们的研究结果证明了创建糖重塑活寄生虫的可行性，为研究功能寄生虫糖生物学和糖介导的宿主-寄生虫相互作用效应奠定了基础。

{"title":"Glycan remodelling of live adult Schistosoma mansoni worms by chemical inhibition of α-mannosidases.","authors":"Eleonore B Kuhlemaijer, Tom Veldhuizen, Isabella A van Hulst, Tessa Liesker, Benjamin J Hulme, Josephine E Forde-Thomas, Gabriel Rinaldi, Karl F Hoffmann, Angela van Diepen, Cornelis H Hokke","doi":"10.1016/j.ijpara.2025.11.002","DOIUrl":"10.1016/j.ijpara.2025.11.002","url":null,"abstract":"<p><p>Schistosomiasis is a neglected tropical disease affecting over 250 million people worldwide. Schistosoma parasites can survive in the human host for years due to their capability to evade and modulate host immune responses. Glycans and glycoproteins produced by schistosomes are thought to play an important role in shaping parasite-host interactions. In addition, N-linked glycans are vital post-translational protein modifications involved in fundamental cellular and developmental processes like protein folding and cell-cell interactions. In this study, we generated live Schistosoma mansoni adult worms with altered N-glycosylation using the α-mannosidase inhibitors kifunensine and swainsonine, compounds which restrict complex N-glycan processing thereby preventing complex N-glycan formation. We show that ex vivo cultured adult schistosomes display a stable N-glycosylation profile during two weeks of culture characterised by roughly one-third mannose and two-third complex glycans. Inhibition of α-mannosidases during culture resulted in a modified N-glycan profile over time: kifunensine-treated parasites were found to contain 76% mannose N-glycans, while swainsonine-treated parasites showed a strongly increased abundance of hybrid glycans and (fucosylated) mannose glycans. These observations are in line with the expected effect of the inhibitors on endoplasmic reticulum and Golgi α-mannosidases, respectively. Additionally, we examined the N-glycan composition of the worm tegument, a major parasitic structure found at the parasite-host interface. The tegument contained mainly complex N-glycans, often carrying the GalNAcβ1-4GlcNAc (LacdiNAc, LDN) motif, different from the rest of the schistosome body. Again, α-mannosidase inhibition changed the N-glycosylation profile of the tegument, similarly as observed for whole worms. No negative effects of any of the treatments on parasite motility or morphology were observed, indicating that the basic biology of the worms in culture was not affected by these N-glycosylation changes. Our results demonstrate the feasibility of creating a live glyco-remodelled parasite, setting the scene for studying functional parasite glycobiology and glycan-mediated effects in host-parasite interaction.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145573884","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}

引用次数: 0

Molecular and morphological support for the synonymy of Nephrostomum and Patagifer: discovery of new species and broad geographic connections. 肾口草和Patagifer同义植物的分子和形态学支持：新种的发现和广泛的地理联系。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-04 DOI: 10.1016/j.ijpara.2025.10.008

María G Díaz González, Danimar López-Hernández, Vasyl V Tkach, Fabiana Drago, Fred D Chibwana, Martina R Laidemitt, Christopher A Blanar, Verónica Núñez, Mariano Dueñas Díaz, Luis A Gomez-Puerta, Sean A Locke

In this study, DNA was sequenced from adults of Patagifer Dietz, 1909 and Nephrostomum Dietz, 1909 (Digenea: Echinostomatidae) collected from avian definitive hosts in Nearctic, Neotropic, Palearctic and Afrotropic regions. Phylogenetic analyses of entire mitochondrial genomes, nuclear rDNA operons, and partial 28S, ITS2, cox1, and nad1 all indicate that Nephrostomum is synonymous with Patagifer, which is given priority, and that head-collar characters formerly used to separate these genera represent traits that vary among closely related congeneric species. Low interspecific divergence in partial 28S (0-0.41 %) in Patagifer has contributed to misidentifications, while mitochondrial markers provided greater resolution and revealed greater species diversity. Six species were included in the present study: P. ramosum, P. bilobus, P. vioscai, P. limai, an unidentified species known only from cercariae, and a new species with distinctive head collar morphology, from Theristicus caerulescens in Argentina. In both P. ramosum and P. bilobus, mitochondrial markers show intercontinental distributions that can be plausibly linked to historical transatlantic expansions of their Old-World avian hosts.

本研究对新北、新北、古北和非北向地区鸟类最终宿主中采集的Patagifer Dietz， 1909和Nephrostomum Dietz， 1909成虫的DNA进行了测序。对整个线粒体基因组、核rDNA操纵子以及部分28S、ITS2、cox1和nad1的系统发育分析都表明，Nephrostomum与Patagifer是同义的，这是优先考虑的，并且以前用于区分这些属的头领特征代表了在密切相关的同源物种中不同的特征。Patagifer中部分28S（0-0.41%）的种间差异较低，导致了误认，而线粒体标记提供了更高的分辨率，揭示了更大的物种多样性。在本研究中发现了6种：P. ramosum， P. bilobus， P. vioscai， P. limai（一种仅从尾蚴中发现的未知种）和阿根廷Theristicus caerulescens中具有独特头领形态的新种。在P. ramosum和P. bilobus中，线粒体标记显示洲际分布可能与它们的旧大陆鸟类宿主的历史跨大西洋扩张有关。

{"title":"Molecular and morphological support for the synonymy of Nephrostomum and Patagifer: discovery of new species and broad geographic connections.","authors":"María G Díaz González, Danimar López-Hernández, Vasyl V Tkach, Fabiana Drago, Fred D Chibwana, Martina R Laidemitt, Christopher A Blanar, Verónica Núñez, Mariano Dueñas Díaz, Luis A Gomez-Puerta, Sean A Locke","doi":"10.1016/j.ijpara.2025.10.008","DOIUrl":"10.1016/j.ijpara.2025.10.008","url":null,"abstract":"<p><p>In this study, DNA was sequenced from adults of Patagifer Dietz, 1909 and Nephrostomum Dietz, 1909 (Digenea: Echinostomatidae) collected from avian definitive hosts in Nearctic, Neotropic, Palearctic and Afrotropic regions. Phylogenetic analyses of entire mitochondrial genomes, nuclear rDNA operons, and partial 28S, ITS2, cox1, and nad1 all indicate that Nephrostomum is synonymous with Patagifer, which is given priority, and that head-collar characters formerly used to separate these genera represent traits that vary among closely related congeneric species. Low interspecific divergence in partial 28S (0-0.41 %) in Patagifer has contributed to misidentifications, while mitochondrial markers provided greater resolution and revealed greater species diversity. Six species were included in the present study: P. ramosum, P. bilobus, P. vioscai, P. limai, an unidentified species known only from cercariae, and a new species with distinctive head collar morphology, from Theristicus caerulescens in Argentina. In both P. ramosum and P. bilobus, mitochondrial markers show intercontinental distributions that can be plausibly linked to historical transatlantic expansions of their Old-World avian hosts.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145451932","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}

引用次数: 0

The sample size matters: evaluating minimum and reasonable values in prevalence studies 样本量很重要：评估患病率研究中的最小值和合理值。

IF 3.2 2区医学 Q1 PARASITOLOGY

International journal for parasitology

Pub Date : 2025-11-01 Epub Date: 2025-05-30 DOI: 10.1016/j.ijpara.2025.05.003

Volodimir Sarabeev , Svitlana Shvydka , Olga Lisitsyna , Mikuláš Oros , Martina Miterpáková , Mária Ždímalová

Estimating sample size is important for prevalence studies, as it directly influences the validity of the research outcomes. Our objective was to highlight constraints in the prevalence assessment and to provide guidance on the delineation of minimum and reasonable sample size. We also assess the prevalence properties as a function of sample size visualizing the median prevalence, confidence intervals, precision, and changes in precision. Constraint analysis indicates that a sample size of less than 15 host individuals will likely result in unacceptable precision in the most cases. Because the prevalence estimate accuracy depends on both sample size and the estimate itself, the minimum sample size may vary widely, from 16 to over 450 individuals, when the prevalence is between 1% and 99%. A sample size of 16–45 elements can be used as a minimum for estimating true prevalence between 10% and 90% with an acceptable precision. However, caution should be exercised with a such small sample size as the prevalence will have a high degree of uncertainty. A simple, practical suggestion for selecting a minimum sample size is to sample until at least 5 infected (cases) and 5 uninfected (non-cases) hosts are detected. This approach is effective in most situations, except in cases of extreme prevalence (1% or 99%). The design of a reasonable sample size should be based on a flexible strategy that takes into account the study objectives, available resources and desired precision. This strategy may based on finding the plateau phase within the precision or confidence intervals curves. As the uncertainty in prevalence decreases rapidly with increasing sample up to 110–135 individuals, but not much more with further increasing sample efforts, opting for a sample size exceeding this threshold, could be considered an optional choice within the prevalence range of 5–95%. We advise authors, editors and reviewers to track sample size in conjunction with the actual prevalence of the parasites and other pathogens. If the minimum sample size is unattainable, authors should acknowledge this limitation, as all data contribute to understanding parasite distribution.

估计样本量对患病率研究很重要，因为它直接影响研究结果的有效性。我们的目标是强调患病率评估中的限制，并为最小和合理样本量的划定提供指导。我们还评估了患病率属性作为样本量的函数，将患病率中位数、置信区间、精度和精度变化可视化。约束分析表明，在大多数情况下，少于15个宿主个体的样本量可能导致无法接受的精度。由于患病率估计的准确性取决于样本量和估计本身，当患病率在1%到99%之间时，最小样本量可能相差很大，从16到450多人。16-45个元素的样本量可作为估计10%至90%的真实患病率的最小值，精度可接受。然而，在样本量如此之小的情况下，应谨慎行事，因为患病率将具有高度的不确定性。选择最小样本量的一个简单实用的建议是，抽样到至少发现5个感染（病例）和5个未感染（非病例）宿主为止。这种方法在大多数情况下是有效的，除了极端流行的情况（1%或99%）。合理样本量的设计应基于灵活的策略，考虑到研究目标、可用资源和所需的精度。该策略可能基于在精度或置信区间曲线内找到平台期。由于患病率的不确定性随着样本量的增加而迅速下降至110-135人，但随着样本量的进一步增加而下降不多，因此选择超过该阈值的样本量，在5%至95%的患病率范围内可被视为可选的选择。我们建议作者、编辑和审稿人结合寄生虫和其他病原体的实际流行情况跟踪样本量。如果无法达到最小样本量，作者应承认这一局限性，因为所有数据都有助于了解寄生虫的分布。

{"title":"The sample size matters: evaluating minimum and reasonable values in prevalence studies","authors":"Volodimir Sarabeev , Svitlana Shvydka , Olga Lisitsyna , Mikuláš Oros , Martina Miterpáková , Mária Ždímalová","doi":"10.1016/j.ijpara.2025.05.003","DOIUrl":"10.1016/j.ijpara.2025.05.003","url":null,"abstract":"<div><div>Estimating sample size is important for prevalence studies, as it directly influences the validity of the research outcomes. Our objective was to highlight constraints in the prevalence assessment and to provide guidance on the delineation of minimum and reasonable sample size. We also assess the prevalence properties as a function of sample size visualizing the median prevalence, confidence intervals, precision, and changes in precision. Constraint analysis indicates that a sample size of less than 15 host individuals will likely result in unacceptable precision in the most cases. Because the prevalence estimate accuracy depends on both sample size and the estimate itself, the minimum sample size may vary widely, from 16 to over 450 individuals, when the prevalence is between 1% and 99%. A sample size of 16–45 elements can be used as a minimum for estimating true prevalence between 10% and 90% with an acceptable precision. However, caution should be exercised with a such small sample size as the prevalence will have a high degree of uncertainty. A simple, practical suggestion for selecting a minimum sample size is to sample until at least 5 infected (cases) and 5 uninfected (non-cases) hosts are detected. This approach is effective in most situations, except in cases of extreme prevalence (1% or 99%). The design of a reasonable sample size should be based on a flexible strategy that takes into account the study objectives, available resources and desired precision. This strategy may based on finding the plateau phase within the precision or confidence intervals curves. As the uncertainty in prevalence decreases rapidly with increasing sample up to 110–135 individuals, but not much more with further increasing sample efforts, opting for a sample size exceeding this threshold, could be considered an optional choice within the prevalence range of 5–95%. We advise authors, editors and reviewers to track sample size in conjunction with the actual prevalence of the parasites and other pathogens. If the minimum sample size is unattainable, authors should acknowledge this limitation, as all data contribute to understanding parasite distribution.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 13","pages":"Pages 683-693"},"PeriodicalIF":3.2,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144199020","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}

引用次数: 0