Pub Date : 2025-01-01Epub Date: 2025-08-27DOI: 10.1016/j.crpvbd.2025.100313
Peihang Hong , Sijia Yu , Hau-You Tzeng , Yu-Hsuan Lin , Chao-Min Wang , Chung-Hung Lai , Shyun Chou
Avian haemosporidian parasites are vector-borne apicomplexans that infect bird species globally and pose considerable challenges in detection due to frequent co-infections and morphological convergence. In the present study, we first used Oxford Nanopore Technologies (ONT) to resolve co-infections of haemosporidians in Swinhoe’s pheasant (Lophura swinhoii), an island-endemic galliform. Blood smears revealed two morphologically distinct gametocyte forms: roundish and circumnuclear, and molecular analyses identified three mitochondrial lineages: two novel Haemoproteus lineages (hLOPSWI01 and hLOPSWI02) and one Plasmodium lineage (pNILSUN01). Phylogenetic reconstruction of mitogenomes resolved hLOPSWI01 and hLOPSWI02 within the Parahaemoproteus clade, whereas pNILSUN01 clustered in the Giovannolaia-Haemamoeba clade. Overall, this study revealed the efficacy of ONT in resolving cryptic co-infections through unfragmented mitogenome assembly, overcoming ambiguities inherent to Sanger sequencing. Our findings establish baseline haemosporidian diversity in L. swinhoii and highlight the necessity of combining long-read genomics with morphological scrutiny for accurate parasite taxonomy, particularly in understudied avian hosts facing conservation threats.
{"title":"Characterization of co-infections of haemosporidian parasites in Swinhoe’s pheasant (Lophura swinhoii): Utilizing nanopore sequencing for species-level detection and mitochondrial-genome analysis","authors":"Peihang Hong , Sijia Yu , Hau-You Tzeng , Yu-Hsuan Lin , Chao-Min Wang , Chung-Hung Lai , Shyun Chou","doi":"10.1016/j.crpvbd.2025.100313","DOIUrl":"10.1016/j.crpvbd.2025.100313","url":null,"abstract":"<div><div>Avian haemosporidian parasites are vector-borne apicomplexans that infect bird species globally and pose considerable challenges in detection due to frequent co-infections and morphological convergence. In the present study, we first used Oxford Nanopore Technologies (ONT) to resolve co-infections of haemosporidians in Swinhoe’s pheasant (<em>Lophura swinhoii</em>), an island-endemic galliform. Blood smears revealed two morphologically distinct gametocyte forms: roundish and circumnuclear, and molecular analyses identified three mitochondrial lineages: two novel <em>Haemoproteus</em> lineages (hLOPSWI01 and hLOPSWI02) and one <em>Plasmodium</em> lineage (pNILSUN01). Phylogenetic reconstruction of mitogenomes resolved hLOPSWI01 and hLOPSWI02 within the <em>Parahaemoproteus</em> clade, whereas pNILSUN01 clustered in the <em>Giovannolaia-Haemamoeba</em> clade. Overall, this study revealed the efficacy of ONT in resolving cryptic co-infections through unfragmented mitogenome assembly, overcoming ambiguities inherent to Sanger sequencing. Our findings establish baseline haemosporidian diversity in <em>L. swinhoii</em> and highlight the necessity of combining long-read genomics with morphological scrutiny for accurate parasite taxonomy, particularly in understudied avian hosts facing conservation threats.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100313"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The nematode family Capillariidae represents a taxonomically complex and understudied group of parasitic nematodes infecting a broad range of vertebrate hosts. Despite more than 300 described species, phylogenetic relationships within the family remain unresolved due to limited molecular data and ongoing taxonomic revisions. In this study, we generated new sequences of the 18S ribosomal RNA gene for Amphibiocapillaria tritonispunctati from the Danube crested newt, Triturus dobrogicus, and four additional capillariid species (Aonchotheca annulosa, Baruscapillaria inflexa, Eucoleus sp. 1 from the common starling Sturnus vulgaris, and Eucoleus sp. 2 from the black-headed gull Chroicocephalus ridibundus) from birds and rodents, expanding the molecular dataset for the group. Phylogenetic analyses using Bayesian inference and Maximum Likelihood methods revealed A. tritonispunctati as the earliest-diverging lineage within the Capillariidae, suggesting deep evolutionary divergence. Our results also supported the monophyly of Eucoleus and Capillaria and confirmed the distinctness of Baruscapillaria. Morphological examination of A. tritonispunctati corroborated its identification and highlighted the weight of diagnostic characters of the genus Amphibiocapillaria. Our findings underscore the need for broader molecular sampling and integrative taxonomy to clarify capillariid systematics and host-parasite relationships, particularly among nematodes from cold-blooded vertebrates.
{"title":"An update on the phylogeny of capillariid nematodes based on 18S rDNA sequences of Amphibiocapillaria tritonispunctati (Diesing, 1851) and four other species","authors":"Roman Svitin , Yaroslav Syrota , Yuriy Kuzmin , Valeriia Dupak , Oksana Nekrasova , Oleksii Marushchak , Kateryna Antipova , Oksana Greben , Zuzana Hurníková , Nataliia Brusentsova , Martina Miterpáková","doi":"10.1016/j.crpvbd.2025.100321","DOIUrl":"10.1016/j.crpvbd.2025.100321","url":null,"abstract":"<div><div>The nematode family Capillariidae represents a taxonomically complex and understudied group of parasitic nematodes infecting a broad range of vertebrate hosts. Despite more than 300 described species, phylogenetic relationships within the family remain unresolved due to limited molecular data and ongoing taxonomic revisions. In this study, we generated new sequences of the 18S ribosomal RNA gene for <em>Amphibiocapillaria tritonispunctati</em> from the Danube crested newt, <em>Triturus dobrogicus</em>, and four additional capillariid species (<em>Aonchotheca annulosa</em>, <em>Baruscapillaria inflexa</em>, <em>Eucoleus</em> sp. 1 from the common starling <em>Sturnus vulgaris</em>, and <em>Eucoleus</em> sp. 2 from the black-headed gull <em>Chroicocephalus ridibundus</em>) from birds and rodents, expanding the molecular dataset for the group. Phylogenetic analyses using Bayesian inference and Maximum Likelihood methods revealed <em>A. tritonispunctati</em> as the earliest-diverging lineage within the Capillariidae, suggesting deep evolutionary divergence. Our results also supported the monophyly of <em>Eucoleus</em> and <em>Capillaria</em> and confirmed the distinctness of <em>Baruscapillaria</em>. Morphological examination of <em>A. tritonispunctati</em> corroborated its identification and highlighted the weight of diagnostic characters of the genus <em>Amphibiocapillaria</em>. Our findings underscore the need for broader molecular sampling and integrative taxonomy to clarify capillariid systematics and host-parasite relationships, particularly among nematodes from cold-blooded vertebrates.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100321"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145157106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-04-15DOI: 10.1016/j.crpvbd.2025.100259
Lassane Koala , Achille S. Nikièma , Mathias Ouedraogo , Justin Compaoré , Clarisse Bougouma , Karim Sanon , Aimé G. Adjami , Moussa S. Sanfo , Inaki Tirados , Philip McCall , Paul Bessel , Thomas R. Unnasch , Daniel A. Boakye , Soungalo Traore , Roch K. Dabire
Current guidelines for onchocerciasis elimination rely heavily upon assessment of the presence of Onchocerca volvulus in the vector Simulium damnosum (sensu lato). This entomological study was conducted over four years in several regions of Burkina Faso to determine the progress made towards interrupting onchocerciasis transmission. Larvae and adult blackflies were collected in eight river basins (Comoé, Léraba, Dienkoa, Mouhoun, Bougouriba, Bambassou, Nakambé, Nazinon and Sissili). Larvae were analyzed by cytotaxonomy, and the adult blackflies analyzed for the presence of infective larvae of O. volvulus by PCR. Blackfly infectivity rates were first determined by year for each basin, then compared to the thresholds established by the WHO. The results indicate that the blackflies collected belong to the savannah group species Simulium damnosum (sensu stricto) and Simulium sirbanum. Hybrids of the two species were also identified. Overall, the prevalence of flies carrying infective larvae was below the threshold of 0.05% established by the WHO, indicating important progress towards the interruption of onchocerciasis transmission in Burkina Faso, although hotspots with infectivity rates well above the WHO’s thresholds remain. Onchocerca volvulus continues to be transmitted in six of the nine basins evaluated, all of which border neighboring countries. These data indicate that it will be necessary to maintain entomological surveillance in these hotspot areas until transmission is interrupted throughout the region.
{"title":"Entomological surveillance of onchocerciasis in Burkina Faso: Progress towards interrupting transmission in blackflies in the main river basins of the country","authors":"Lassane Koala , Achille S. Nikièma , Mathias Ouedraogo , Justin Compaoré , Clarisse Bougouma , Karim Sanon , Aimé G. Adjami , Moussa S. Sanfo , Inaki Tirados , Philip McCall , Paul Bessel , Thomas R. Unnasch , Daniel A. Boakye , Soungalo Traore , Roch K. Dabire","doi":"10.1016/j.crpvbd.2025.100259","DOIUrl":"10.1016/j.crpvbd.2025.100259","url":null,"abstract":"<div><div>Current guidelines for onchocerciasis elimination rely heavily upon assessment of the presence of <em>Onchocerca volvulus</em> in the vector <em>Simulium damnosum</em> (<em>sensu lato</em>). This entomological study was conducted over four years in several regions of Burkina Faso to determine the progress made towards interrupting onchocerciasis transmission. Larvae and adult blackflies were collected in eight river basins (Comoé, Léraba, Dienkoa, Mouhoun, Bougouriba, Bambassou, Nakambé, Nazinon and Sissili). Larvae were analyzed by cytotaxonomy, and the adult blackflies analyzed for the presence of infective larvae of <em>O. volvulus</em> by PCR. Blackfly infectivity rates were first determined by year for each basin, then compared to the thresholds established by the WHO. The results indicate that the blackflies collected belong to the savannah group species <em>Simulium damnosum</em> (<em>sensu stricto</em>) and <em>Simulium sirbanum</em>. Hybrids of the two species were also identified. Overall, the prevalence of flies carrying infective larvae was below the threshold of 0.05% established by the WHO, indicating important progress towards the interruption of onchocerciasis transmission in Burkina Faso, although hotspots with infectivity rates well above the WHO’s thresholds remain. <em>Onchocerca volvulus</em> continues to be transmitted in six of the nine basins evaluated, all of which border neighboring countries. These data indicate that it will be necessary to maintain entomological surveillance in these hotspot areas until transmission is interrupted throughout the region.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100259"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-07-06DOI: 10.1016/j.crpvbd.2025.100292
Deborah B. Oladele , Martin Swain , Guy Robinson , Amanda Clare , Rachel M. Chalmers
Cryptosporidium spp. are known to cause gastroenteritis (cryptosporidiosis) in numerous hosts, including humans. Understanding the diversity within this genus of parasites requires accurate subtyping, which is frequently performed by sequencing part of the gp60 (60-kDa glycoprotein) gene. This literature review examines Cryptosporidium hominis and Cryptosporidium parvum gp60 subtypes reported between December 2018 and January 2024 in humans, livestock, and non-human primates (NHPs). The review highlights emerging trends in the subtypes reported and reveals the shifting dominance of subtype families, which can be influenced by factors such as anthroponotic interactions. The C. parvum IIa and IId families remain major contributors to infections across a variety of hosts, with recent reports indicating the continued emergence of the IId family. Furthermore, previously established and newly reported subtypes detected in NHPs highlight the potential for genetic recombination between human-adapted and NHP-adapted subtypes.
{"title":"A review of recent Cryptosporidium hominis and Cryptosporidium parvum gp60 subtypes","authors":"Deborah B. Oladele , Martin Swain , Guy Robinson , Amanda Clare , Rachel M. Chalmers","doi":"10.1016/j.crpvbd.2025.100292","DOIUrl":"10.1016/j.crpvbd.2025.100292","url":null,"abstract":"<div><div><em>Cryptosporidium</em> spp. are known to cause gastroenteritis (cryptosporidiosis) in numerous hosts, including humans. Understanding the diversity within this genus of parasites requires accurate subtyping, which is frequently performed by sequencing part of the <em>gp60</em> (60-kDa glycoprotein) gene. This literature review examines <em>Cryptosporidium hominis</em> and <em>Cryptosporidium parvum gp60</em> subtypes reported between December 2018 and January 2024 in humans, livestock, and non-human primates (NHPs). The review highlights emerging trends in the subtypes reported and reveals the shifting dominance of subtype families, which can be influenced by factors such as anthroponotic interactions. The <em>C. parvum</em> IIa and IId families remain major contributors to infections across a variety of hosts, with recent reports indicating the continued emergence of the IId family. Furthermore, previously established and newly reported subtypes detected in NHPs highlight the potential for genetic recombination between human-adapted and NHP-adapted subtypes.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100292"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144680211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-07-31DOI: 10.1016/j.crpvbd.2025.100302
Anna M. Ciećkiewicz , Julia Ettlin , Eva Veronesi , Andrea Marti , Obdulio Garcia-Nicolas , Jeannine Hauri , Artur Summerfield , Alexander Mathis , Niels O. Verhulst
The Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus endemic to much of Asia and the Western Pacific, both temperate and tropical regions. Globalisation and the expansion of invasive mosquito species raise concerns about their potential establishment in Europe and other currently non-endemic regions. However, limited knowledge exists regarding the vector competence of European mosquitoes, particularly under the region’s characteristic fluctuating temperatures. While Culex species are primary JEV vectors, the role of Aedes mosquitoes remains unclear. This study assessed the vector competence of field-caught or low-generation colony-derived Aedes albopictus, Ae. japonicus, and Ae. vexans from Switzerland under a fluctuating temperature regime (16–28 °C), using Culex quinquefasciatus as a reference. Mosquitoes were exposed to JEV genotype I-b and incubated for 7 and 14 days. RT-qPCR was used to analyse mosquito body parts and saliva to determine infection, dissemination, transmission rates and transmission efficiency. Aedes albopictus, Ae. japonicus, and Cx. quinquefasciatus were competent vectors. Aedes japonicus showed the highest infection rate (13.6%, 9/66) compared to Ae. albopictus (3.0%, 3/101) and Cx. quinquefasciatus (6.9%, 7/101), while Ae. vexans was refractory (0/80). Dissemination was observed in Ae. japonicus already 7 days post-exposure, preceding other species. Aedes japonicus had the highest transmission rate (66.7%, 2/3) and efficiency (6.1%, 2/33). This study demonstrates that European Aedes mosquitoes can serve as JEV vectors under fluctuating temperatures and may contribute to virus transmission despite being considered secondary vectors. The findings emphasise that species-specific assessments under realistic temperatures are essential in evaluating the risk of JEV establishment in temperate regions.
{"title":"Vector competence of European Aedes mosquito species for Japanese encephalitis virus under fluctuating temperature conditions","authors":"Anna M. Ciećkiewicz , Julia Ettlin , Eva Veronesi , Andrea Marti , Obdulio Garcia-Nicolas , Jeannine Hauri , Artur Summerfield , Alexander Mathis , Niels O. Verhulst","doi":"10.1016/j.crpvbd.2025.100302","DOIUrl":"10.1016/j.crpvbd.2025.100302","url":null,"abstract":"<div><div>The Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus endemic to much of Asia and the Western Pacific, both temperate and tropical regions. Globalisation and the expansion of invasive mosquito species raise concerns about their potential establishment in Europe and other currently non-endemic regions. However, limited knowledge exists regarding the vector competence of European mosquitoes, particularly under the region’s characteristic fluctuating temperatures. While <em>Culex</em> species are primary JEV vectors, the role of <em>Aedes</em> mosquitoes remains unclear. This study assessed the vector competence of field-caught or low-generation colony-derived <em>Aedes albopictus</em>, <em>Ae. japonicus</em>, and <em>Ae. vexans</em> from Switzerland under a fluctuating temperature regime (16–28 °C), using <em>Culex quinquefasciatus</em> as a reference. Mosquitoes were exposed to JEV genotype I-b and incubated for 7 and 14 days. RT-qPCR was used to analyse mosquito body parts and saliva to determine infection, dissemination, transmission rates and transmission efficiency. <em>Aedes albopictus</em>, <em>Ae. japonicus</em>, and <em>Cx. quinquefasciatus</em> were competent vectors. <em>Aedes japonicus</em> showed the highest infection rate (13.6%, 9/66) compared to <em>Ae. albopictus</em> (3.0%, 3/101) and <em>Cx. quinquefasciatus</em> (6.9%, 7/101), while <em>Ae. vexans</em> was refractory (0/80). Dissemination was observed in <em>Ae. japonicus</em> already 7 days post-exposure, preceding other species. <em>Aedes japonicus</em> had the highest transmission rate (66.7%, 2/3) and efficiency (6.1%, 2/33). This study demonstrates that European <em>Aedes</em> mosquitoes can serve as JEV vectors under fluctuating temperatures and may contribute to virus transmission despite being considered secondary vectors. The findings emphasise that species-specific assessments under realistic temperatures are essential in evaluating the risk of JEV establishment in temperate regions.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100302"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144771720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent studies have suggested that the tick Ixodes ricinus expresses nAChR subtypes which are activated by acetylcholine. Here, we investigated the potential of the Iricα6 subunit to form a functional receptor when expressed in Xenopus laevis oocytes. Electrophysiological recordings using a two-electrode voltage clamp suggested that the Iricα6 subunit can form a functional homomeric receptor when expressed alone or with chaperone proteins such as RIC-3, UNC-50 and UNC-74. We also found that Iricα6 is a non-selective cation channel. ACh-induced currents were blocked by the nicotinic antagonists methyllicaconitine and dihydro-β-erythroidine. In addition, the nicotinic antagonists α-bungarotoxin and mecamylamine elicited agonist-like responses, with EC50 values of 3.48 nM and 12.60 nM, respectively. These data indicated that Iricα6 homomeric receptors could have different pharmacological properties compared to homomeric receptors expressed in other species.
{"title":"Functional expression and properties of the tick α6 homomeric nicotinic acetylcholine receptor in Xenopus laevis oocytes","authors":"Alison Cartereau , Khalid Boussaine , Emiliane Taillebois , Steeve H. Thany","doi":"10.1016/j.crpvbd.2025.100341","DOIUrl":"10.1016/j.crpvbd.2025.100341","url":null,"abstract":"<div><div>Recent studies have suggested that the tick <em>Ixodes ricinus</em> expresses nAChR subtypes which are activated by acetylcholine. Here, we investigated the potential of the Iricα6 subunit to form a functional receptor when expressed in <em>Xenopus laevis</em> oocytes. Electrophysiological recordings using a two-electrode voltage clamp suggested that the Iricα6 subunit can form a functional homomeric receptor when expressed alone or with chaperone proteins such as RIC-3, UNC-50 and UNC-74. We also found that Iricα6 is a non-selective cation channel. ACh-induced currents were blocked by the nicotinic antagonists methyllicaconitine and dihydro-β-erythroidine. In addition, the nicotinic antagonists α-bungarotoxin and mecamylamine elicited agonist-like responses, with EC<sub>50</sub> values of 3.48 nM and 12.60 nM, respectively. These data indicated that Iricα6 homomeric receptors could have different pharmacological properties compared to homomeric receptors expressed in other species.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100341"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145693428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-08-30DOI: 10.1016/j.crpvbd.2025.100314
Lucia Dinisová , Eva Čisovská Bazsalovicsová , Karl Skírnisson , Ivica Králová-Hromadová
The diphyllobothriid tapeworm Dibothriocephalus ditremus, one of the three Dibothriocephalus species native to Europe, parasitises exclusively piscivorous birds and has not yet been detected in mammals. This is probably the reason why there is much less molecular data on this tapeworm. The aim of our study was to determine the genetic structure of the D. ditremus populations from Europe, namely Iceland, for the first time. To exclude any possible misidentifications between sympatrically occurring D. ditremus and D. dendriticus, D. dendriticus from Iceland was also analysed. Great genetic diversity of D. ditremus, displayed by a large number of cytochrome c oxidase subunit 1 (cox1) haplotypes and three distant clusters, contrasted sharply with the lower genetic variation in D. dendriticus. Previously published cox1 sequences of D. ditremus from different localities in Europe (UK - Scotland), Asia (Russia and Japan) and North America (USA - Oregon) were also included in the analysis in order to determine the genetic architecture of D. ditremus at a broader geographical scale. While the sequences of tapeworms from Scotland and Russia were placed in D. ditremus Clusters 2 and 3, the sample from USA (Oregon) displayed a unique position distant from the Icelandic tapeworms. Japanese samples of D. ditremus and Diphyllobothrium hottai formed a common clade, indicating their conspecificity. The unexpected output of the analysis was a unique position of the currently detected Haplotype 31 of a tapeworm from Iceland, which was distant from all other D. ditremus individuals from Iceland, but showed close relationships with the Japanese D. ditremus/D. hottai cluster. Further studies are needed to reveal if D. ditremus represent a complex of genetically diversified populations, or more species occur in salmonids in the Northern Hemisphere.
{"title":"Dibothriocephalosis in salmonids from Iceland: A more complex taxonomic problem than assumed until now?","authors":"Lucia Dinisová , Eva Čisovská Bazsalovicsová , Karl Skírnisson , Ivica Králová-Hromadová","doi":"10.1016/j.crpvbd.2025.100314","DOIUrl":"10.1016/j.crpvbd.2025.100314","url":null,"abstract":"<div><div>The diphyllobothriid tapeworm <em>Dibothriocephalus ditremus</em>, one of the three <em>Dibothriocephalus</em> species native to Europe, parasitises exclusively piscivorous birds and has not yet been detected in mammals. This is probably the reason why there is much less molecular data on this tapeworm. The aim of our study was to determine the genetic structure of the <em>D. ditremus</em> populations from Europe, namely Iceland, for the first time. To exclude any possible misidentifications between sympatrically occurring <em>D. ditremus</em> and <em>D. dendriticus</em>, <em>D. dendriticus</em> from Iceland was also analysed. Great genetic diversity of <em>D. ditremus</em>, displayed by a large number of cytochrome <em>c</em> oxidase subunit 1 (<em>cox</em>1) haplotypes and three distant clusters, contrasted sharply with the lower genetic variation in <em>D. dendriticus.</em> Previously published <em>cox</em>1 sequences of <em>D. ditremus</em> from different localities in Europe (UK - Scotland), Asia (Russia and Japan) and North America (USA - Oregon) were also included in the analysis in order to determine the genetic architecture of <em>D. ditremus</em> at a broader geographical scale. While the sequences of tapeworms from Scotland and Russia were placed in <em>D. ditremus</em> Clusters 2 and 3, the sample from USA (Oregon) displayed a unique position distant from the Icelandic tapeworms. Japanese samples of <em>D. ditremus</em> and <em>Diphyllobothrium hottai</em> formed a common clade, indicating their conspecificity. The unexpected output of the analysis was a unique position of the currently detected Haplotype 31 of a tapeworm from Iceland, which was distant from all other <em>D. ditremus</em> individuals from Iceland, but showed close relationships with the Japanese <em>D. ditremus</em>/<em>D. hottai</em> cluster. Further studies are needed to reveal if <em>D. ditremus</em> represent a complex of genetically diversified populations, or more species occur in salmonids in the Northern Hemisphere.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100314"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145048753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-10-17DOI: 10.1016/j.crpvbd.2025.100330
Elena Infante González-Mohino , Iván Rodríguez-Escolar , Alfonso Balmori-de la Puente , Manuel Collado-Cuadrado , Elena Carretón , José Alberto Montoya-Alonso , Rodrigo Morchón
Heartworm disease (cardiopulmonary dirofilariosis) is a vector-borne parasitic disease caused by the parasitic nematode Dirofilaria immitis. It is transmitted by different species of culicid mosquitoes, with Culex pipiens being the most important species in the Iberian Peninsula, and Culex theileri in the Canary Islands and Madeira. The development of risk maps using ecological niche models (ENMs) has established itself as a useful tool in the prevention and control of various parasitic infections in different territories. The aim of this study was to produce monthly infection risk maps for all territories in Spain and Portugal, based on ecological modelling of Cx. pipiens in the Iberian Peninsula, the Islands and Madeira, and of Cx. pipiens together with Cx. theileri in the Canary Islands. These models were weighted with the number of generations of D. immitis calculated each month, thus obtaining infection risk maps for each month of the year. Models indicate that the risk of transmission is highest in summer, gradually decreasing in autumn until reaching zero levels in winter in most territories. In the Iberian Peninsula, the most affected areas are the south, the Mediterranean coast and the Balearic Islands. In the Canary Islands, the risk remains moderate during winter due to its thermal stability, especially in densely populated coastal areas. A similar pattern is observed in the Azores Islands and Madeira, where the risk, although lower, persists in winter and is concentrated in low-lying, inhabited areas. This approach allows the dynamics of heartworm infection to be studied throughout the year and constitutes the first time that monthly risk models have been developed in these territories, as well as the first risk maps for D. immitis transmission in the Azores Islands and Madeira.
{"title":"Monthly analysis of the current risk of heartworm transmission in Portugal and Spain through ecological niche modeling as a control measure","authors":"Elena Infante González-Mohino , Iván Rodríguez-Escolar , Alfonso Balmori-de la Puente , Manuel Collado-Cuadrado , Elena Carretón , José Alberto Montoya-Alonso , Rodrigo Morchón","doi":"10.1016/j.crpvbd.2025.100330","DOIUrl":"10.1016/j.crpvbd.2025.100330","url":null,"abstract":"<div><div>Heartworm disease (cardiopulmonary dirofilariosis) is a vector-borne parasitic disease caused by the parasitic nematode <em>Dirofilaria immitis</em>. It is transmitted by different species of culicid mosquitoes, with <em>Culex pipiens</em> being the most important species in the Iberian Peninsula, and <em>Culex theileri</em> in the Canary Islands and Madeira. The development of risk maps using ecological niche models (ENMs) has established itself as a useful tool in the prevention and control of various parasitic infections in different territories. The aim of this study was to produce monthly infection risk maps for all territories in Spain and Portugal, based on ecological modelling of <em>Cx. pipiens</em> in the Iberian Peninsula, the Islands and Madeira, and of <em>Cx. pipiens</em> together with <em>Cx. theileri</em> in the Canary Islands. These models were weighted with the number of generations of <em>D. immitis</em> calculated each month, thus obtaining infection risk maps for each month of the year. Models indicate that the risk of transmission is highest in summer, gradually decreasing in autumn until reaching zero levels in winter in most territories. In the Iberian Peninsula, the most affected areas are the south, the Mediterranean coast and the Balearic Islands. In the Canary Islands, the risk remains moderate during winter due to its thermal stability, especially in densely populated coastal areas. A similar pattern is observed in the Azores Islands and Madeira, where the risk, although lower, persists in winter and is concentrated in low-lying, inhabited areas. This approach allows the dynamics of heartworm infection to be studied throughout the year and constitutes the first time that monthly risk models have been developed in these territories, as well as the first risk maps for <em>D. immitis</em> transmission in the Azores Islands and Madeira.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100330"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145361509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-06-25DOI: 10.1016/j.crpvbd.2025.100288
Juan D. Mosquera , Sonia Zapata , Denis Augot
Bluetongue virus (BTV) is an Orbivirus transmitted by Culicoides biting midges and is the causative agent of bluetongue disease in wild and domestic ruminants. Culicoides insignis is the primary vector of BTV in Florida, Central America, the Caribbean, and South America. In Ecuador, recent investigations have reported the presence of BTV in cattle and identified C. insignis as the dominant species in localities from the Amazon Basin and Andean foothills. Understanding the host-feeding patterns of blood-feeding insects and evaluating their role in pathogen transmission are essential for elucidating the epidemiology of vector-borne diseases. To that end, we investigated the presence of BTV in unengorged C. insignis females collected in two localities: Cotundo, where BTV had previously been reported in cattle, and Paraiso Escondido located near (∼35 km) a site with a known history of BTV circulation. A total of 1773 female Culicoides spp. specimens were collected, of which 326 (18.38 %) were C. insignis. We identified the blood meal sources of engorged C. insignis females from both localities. Our results provide additional evidence to support the role of C. insignis as vector of BTV in Ecuador.
{"title":"Culicoides insignis in Ecuador: Molecular identification of blood meals and detection of bluetongue virus","authors":"Juan D. Mosquera , Sonia Zapata , Denis Augot","doi":"10.1016/j.crpvbd.2025.100288","DOIUrl":"10.1016/j.crpvbd.2025.100288","url":null,"abstract":"<div><div>Bluetongue virus (BTV) is an <em>Orbivirus</em> transmitted by <em>Culicoides</em> biting midges and is the causative agent of bluetongue disease in wild and domestic ruminants. <em>Culicoides insignis</em> is the primary vector of BTV in Florida, Central America, the Caribbean, and South America. In Ecuador, recent investigations have reported the presence of BTV in cattle and identified <em>C. insignis</em> as the dominant species in localities from the Amazon Basin and Andean foothills. Understanding the host-feeding patterns of blood-feeding insects and evaluating their role in pathogen transmission are essential for elucidating the epidemiology of vector-borne diseases. To that end, we investigated the presence of BTV in unengorged <em>C. insignis</em> females collected in two localities: Cotundo, where BTV had previously been reported in cattle, and Paraiso Escondido located near (∼35 km) a site with a known history of BTV circulation. A total of 1773 female <em>Culicoides</em> spp. specimens were collected, of which 326 (18.38 %) were <em>C. insignis</em>. We identified the blood meal sources of engorged <em>C. insignis</em> females from both localities. Our results provide additional evidence to support the role of <em>C. insignis</em> as vector of BTV in Ecuador.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100288"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144534691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-01Epub Date: 2025-01-31DOI: 10.1016/j.crpvbd.2025.100248
Nyanda C. Justine , Humphrey D. Mazigo , Antje Fuss , Bonnie L. Webster , Eveline T. Konje , Klaus Brehm , Andreas Mueller
Urogenital schistosomiasis is a neglected tropical disease of significant public health concern caused by the trematode species Schistosoma haematobium. Its transmission is localised and heterogeneous, with seasonal occurrences in Tanzania primarily facilitated by Bulinus spp. snails, which serve as intermediate hosts. To plan effective, data-driven control measures, it is crucial to understand the epidemiology of schistosomes in these snails. This study aimed to investigate the seasonal distribution, abundance, and Schistosoma spp. infections (assessed via cercarial emergence) in Bulinus spp. snails in two districts, Maswa and Meatu, in the Simiyu Region of Tanzania. Malacological surveys were conducted at 90 sites in total, comprising sites in 35 rivers, 32 ponds, and 23 branching streams. Each study site was sampled once during the rainy season and once during the dry season. Snails were collected using a standard scoop- and handpicking technique by two people for 15 min at each site. The collected snails were morphologically identified and subjected to a cercarial emergence experiment. Water physicochemical characteristics were recorded simultaneously with snail collection using a portable multiparameter water meter. The data were analysed using STATA v. 17. A total of 4997 Bulinus spp. snails were collected from 90 sites in the two districts. Of these, 91.4% (95% CI: 90.5–92.1%) were morphologically identified as Bulinus nasutus and 8.6% (95% CI: 7.8–9.4%) were identified as Bulinus globosus. Bulinus spp. snail abundance was almost evenly distributed across seasons, with 50.4% (95% CI: 48.9–51.7%) collected during the dry season and 49.6% (95% CI: 48.2–51.0%) collected during the rainy season. Water temperature and salinity were significantly negatively correlated with snail abundance (both P < 0.001). Schistosoma spp. cercarial emergence followed a seasonal pattern and was significantly higher during the rainy season (P = 0.005). Our findings underscore that B. nasutus was the most abundant freshwater snail distributed at nearly all the study sites during the rainy and dry seasons. Therefore, appropriate snail control strategies are recommended to complement ongoing schistosomiasis control strategies in the Simiyu Region.
{"title":"Seasonal distribution and cercarial shedding of Bulinus spp. snails: Implications for urogenital schistosomiasis control in the Simiyu Region, northwestern Tanzania","authors":"Nyanda C. Justine , Humphrey D. Mazigo , Antje Fuss , Bonnie L. Webster , Eveline T. Konje , Klaus Brehm , Andreas Mueller","doi":"10.1016/j.crpvbd.2025.100248","DOIUrl":"10.1016/j.crpvbd.2025.100248","url":null,"abstract":"<div><div>Urogenital schistosomiasis is a neglected tropical disease of significant public health concern caused by the trematode species <em>Schistosoma haematobium</em>. Its transmission is localised and heterogeneous, with seasonal occurrences in Tanzania primarily facilitated by <em>Bulinus</em> spp. snails, which serve as intermediate hosts. To plan effective, data-driven control measures, it is crucial to understand the epidemiology of schistosomes in these snails. This study aimed to investigate the seasonal distribution, abundance, and <em>Schistosoma</em> spp. infections (assessed <em>via</em> cercarial emergence) in <em>Bulinus</em> spp. snails in two districts, Maswa and Meatu, in the Simiyu Region of Tanzania. Malacological surveys were conducted at 90 sites in total, comprising sites in 35 rivers, 32 ponds, and 23 branching streams. Each study site was sampled once during the rainy season and once during the dry season. Snails were collected using a standard scoop- and handpicking technique by two people for 15 min at each site. The collected snails were morphologically identified and subjected to a cercarial emergence experiment. Water physicochemical characteristics were recorded simultaneously with snail collection using a portable multiparameter water meter. The data were analysed using STATA v. 17. A total of 4997 <em>Bulinus</em> spp<em>.</em> snails were collected from 90 sites in the two districts. Of these, 91.4% (95% CI: 90.5–92.1%) were morphologically identified as <em>Bulinus nasutus</em> and 8.6% (95% CI: 7.8–9.4%) were identified as <em>Bulinus globosus</em>. <em>Bulinus</em> spp. snail abundance was almost evenly distributed across seasons, with 50.4% (95% CI: 48.9–51.7%) collected during the dry season and 49.6% (95% CI: 48.2–51.0%) collected during the rainy season. Water temperature and salinity were significantly negatively correlated with snail abundance (both <em>P</em> < 0.001). <em>Schistosoma</em> spp. cercarial emergence followed a seasonal pattern and was significantly higher during the rainy season (<em>P</em> = 0.005). Our findings underscore that <em>B. nasutus</em> was the most abundant freshwater snail distributed at nearly all the study sites during the rainy and dry seasons. Therefore, appropriate snail control strategies are recommended to complement ongoing schistosomiasis control strategies in the Simiyu Region.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100248"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号