Current research in parasitology & vector-borne diseases最新文献

{"title":"The spatial heterogeneity of malaria transmission: An entomological investigation in a highly endemic setting of Burkina Faso","authors":"Eleonora Perugini ,&nbsp;Cristiana Poggi ,&nbsp;Martina Micocci ,&nbsp;Verena Pichler ,&nbsp;Luca Nelli ,&nbsp;Alessandra della Torre ,&nbsp;Wamdaogo M. Guelbeogo ,&nbsp;Marco Pombi","doi":"10.1016/j.crpvbd.2025.100300","DOIUrl":"10.1016/j.crpvbd.2025.100300","url":null,"abstract":"<div><div>Malaria hotspots are often observed at multiple spatial scales, shaped by environmental, entomological, and human factors. The dynamics underlying transmission heterogeneity remains poorly understood, limiting the effectiveness of locally tailored control strategies. This study investigates transmission spatial patterns in an ITN-covered Burkina Faso village, exploiting entomological predictors of exposure risk in relation to environmental factors. Pyrethrum spray collections were conducted in 59 houses across the north-west, east, and south areas of Goden village. <em>Anopheles</em> mosquitoes were analysed for species identification, human blood index (HBI), sporozoite rate (SR), and infected human blood meal rate (IHBM). Entomological indices and mosquito abundance were spatially interpolated and then included in GAMLSS models to assess the effects of ecological variables. <em>Anopheles coluzzii</em> was the dominant vector, representing 79% of <em>An. gambiae</em> (<em>s.l.</em>) collected (<em>n</em> = 1492). Blood-meal analysis indicated low anthropophily (HBI = 45%, <em>n</em> = 687), yet SR was high (10%, <em>n</em> = 930), likely sustained by elevated parasite circulation among residents. In fact, the IHBM revealed that 43% of human blood meals contained erythrocytic parasite stages. Statistics highlighted a spatial effect on human-vector contacts and proportionally higher values of HBI, SR, and IHBM clustering in the north-west area. This suggests the presence of a hotspot where inhabitants were more exposed to infectious bites, and vectors had greater chances of acquiring <em>Plasmodium</em> spp. Notably, infective mosquitoes had 1.8-fold higher anthropophily than non-infective ones. Although further investigations are needed, this study unveiled a possible mechanism sustaining local hotspots by linking uneven biting exposure of human reservoir and increased anthropophily of infective mosquitoes.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100300"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766988","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}

{"title":"Design, development, and testing of a new multi-locus sequence typing scheme for the zoonotic pathogen Cryptosporidium parvum","authors":"Karin Troell ,&nbsp;Christen Rune Stensvold ,&nbsp;Anna Rosa Sannella ,&nbsp;Martha Betson ,&nbsp;Emma Östlund ,&nbsp;Rachel M. Chalmers ,&nbsp;Umer Chaudhry ,&nbsp;Rebecca Davidson ,&nbsp;Lauren Davies ,&nbsp;Ralf Ignatius ,&nbsp;Anton de Jong ,&nbsp;Gregory Karadjian ,&nbsp;Karim Adjou ,&nbsp;Christian Klotz ,&nbsp;Sokratis Ptochos ,&nbsp;Guy Robinson ,&nbsp;Jeroen Roelfsema ,&nbsp;Barbara Soba ,&nbsp;Jacek Sroka ,&nbsp;Paolo Vatta ,&nbsp;Simone M. Cacciò","doi":"10.1016/j.crpvbd.2025.100308","DOIUrl":"10.1016/j.crpvbd.2025.100308","url":null,"abstract":"<div><div>The zoonotic parasite <em>Cryptosporidium parvum</em> is an important global cause of diarrheal disease in humans and young ruminants. Molecular typing is essential to track transmission routes and identify clusters of cases. Here, we developed a novel multi-locus sequence typing (MLST) scheme based on single nucleotide polymorphisms (SNPs) in unlinked markers. Coding regions with high variability were identified by comparing whole genome sequences (WGS) from 43 human- and 92 ruminant-derived <em>C. parvum</em> samples collected across Europe. We first selected 18 markers and showed that they provide high discrimination among the samples with WGS data, with 88% of the MLSTs being singletons. Next, we defined a MLST based on eight genetically unlinked markers and generated sequence data from 305 <em>C. parvum</em> samples, collected from four different host species and 13 European countries. We consolidated a set of 365 fully genotyped samples, characterized by the presence of 154 different MLSTs, 105 of which were singletons. Network analyses showed no complete clustering of samples by host species or country of origin at the European scale. We further showed that samples with <em>gp60</em> subtypes that are common in Europe are divided into many MLSTs by the new scheme, highlighting its increased discriminatory ability. However, the applicability of the scheme in public health settings is limited by its cost, turnaround time, and scalability. To achieve discrimination of <em>C. parvum</em> samples based on SNPs, a large number of loci needs to be analysed, and this is feasible using amplicon sequencing technologies.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100308"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144885418","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}

{"title":"Thelaziosis in central Italy: Molecular detection of a variant haplotype in a human case and epidemiological aspects","authors":"Serena Cavallero ,&nbsp;Ilaria Bellini ,&nbsp;Tommaso Ascoli Bartoli ,&nbsp;Eleonora Perugini ,&nbsp;Cristiana Poggi ,&nbsp;Claudia Chiovoloni ,&nbsp;Silvia Rondón ,&nbsp;Stefano D’Amelio ,&nbsp;Simonetta Mattiucci ,&nbsp;Mariaelisa Carbonara ,&nbsp;Domenico Otranto ,&nbsp;Marco Pombi ,&nbsp;Simona Gabrielli","doi":"10.1016/j.crpvbd.2025.100316","DOIUrl":"10.1016/j.crpvbd.2025.100316","url":null,"abstract":"<div><div><em>Thelazia callipaeda</em> is an emerging zoonotic nematode responsible for ocular infection in Europe, transmitted by lachryphagous drosophilid flies of the genus <em>Phortica</em>. In this study, we updated the epidemiological picture of thelaziosis in Italy analysing parasites collected from a human case, in the vector <em>Phortica variegata</em>, and in a single naturally infected definitive host (dog), all from the same geographical area, the Latium region, central Italy. Median joining network and phylogenetic analyses based on the mitochondrial cytochrome <em>c</em> oxidase subunit 1 (<em>cox</em>1) gene of <em>T. callipaeda</em> revealed a novel variant haplotype, named Haplotype 22, for the nematode from the human patient, distinct from the common Haplotype 1, detected for the nematodes from the infected dog and the positive specimens of <em>P. variegata</em> flies. The discovery of the new circulating haplotype variant, besides the dominant Haplotype 1, the so far only known haplotype in Europe, expands the knowledge on the genetic polymorphism of <em>T. callipaeda</em>. The results obtained support the hypothesis that the European population of <em>T. callipaeda</em>, despite its lower level of polymorphism, is genetically differentiated from that occurring in Asia, as previously suggested. These findings highlight the importance of the parasite’s monitoring in Europe, after its first detection in the late 1990s, possibly adopting a One Health approach. The zoonotic role of <em>T. callipaeda</em>, transmitted by <em>Phortica</em> spp. in urban settings of Italy as here demonstrated, evidences the need for increasing medical awareness.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100316"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145018851","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}

{"title":"Hemotropic Mycoplasma in cattle and Asian water buffalo in Thailand: Revealing globally distributed sequence types and regional genetic diversity","authors":"Apinya Arnuphapprasert ,&nbsp;Yudhi Ratna Nugraheni ,&nbsp;Morakot Kaewthamasorn","doi":"10.1016/j.crpvbd.2025.100318","DOIUrl":"10.1016/j.crpvbd.2025.100318","url":null,"abstract":"<div><div>Hemotropic mycoplasmas, particularly <em>Mycoplasma wenyonii</em> and “<em>Candidatus</em> Mycoplasma haematobovis”, are increasingly recognized as emerging vector-borne pathogens of veterinary importance in cattle and buffalo. Due to their complex epidemiology and the limited understanding of their pathogenic mechanisms, hemoplasma infections in large ruminants are often underdiagnosed and underreported, especially in resource-limited settings. This study investigated the genetic diversity and phylogenetic relationships of hemotropic <em>Mycoplasma</em> species in blood samples collected from cattle and buffalo across seven provinces in Thailand between 2016 and 2023. A total of 422 samples (214 from cattle and 208 from buffalo) were analyzed, with 373 testing positive for hemotropic <em>Mycoplasma</em> DNA. Phylogenetic analyses of the 16S and 23S rRNA gene sequences revealed two distinct clades corresponding to <em>M. wenyonii</em> and “<em>Ca</em>. M. haematobovis”. Most sequences clustered with <em>M. wenyonii</em> strains from multiple countries, while a smaller subset grouped with “<em>Ca.</em> M. haematobovis” strains. Intraspecific sequence similarity among <em>M. wenyonii</em> 16S rRNA gene sequences ranged from 97.29% to 100%, whereas “<em>Ca.</em> M. haematobovis” sequences showed similarities ranging from 99.75% to 100%. Interspecific similarity between the two species ranged from 83.48% to 84.34%. For the 23S rRNA gene sequences, <em>M. wenyonii</em> exhibited intraspecific similarity levels ranging from 90.94% to 100%, while “<em>Ca</em>. M. haematobovis” sequences demonstrated 99.53% similarity; interspecific similarity for this gene ranged from 76.69% to 77.34%. We identified 11 nucleotide sequence types (ntSTs) for <em>M. wenyonii</em>, with ntST10 being the most widely distributed, shared among isolates from Cuba, Thailand, Japan, and Brazil. The single “<em>Ca</em>. M. haematobovis” sequence type detected in this study clustered within ntST7, alongside sequences from Cuba, Malaysia, Brazil, Turkey, Kyrgyzstan, and Japan. These findings highlight the substantial genetic diversity and broad geographical distribution of hemotropic <em>Mycoplasma</em> species in Thailand and emphasize the critical importance of molecular screening for managing the risk of pathogen transmission within livestock populations.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100318"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145104524","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}

{"title":"Hidden Plasmodium diversity revealed in southeastern Asian passerines using next-generation amplicon sequencing","authors":"Dragomir Damnjanović ,&nbsp;Masoud Nazarizadeh ,&nbsp;Milena Nováková ,&nbsp;Nguyễn Văn Linh ,&nbsp;Oleg Tolstenkov ,&nbsp;Anvar Kerimov ,&nbsp;Andrey Bushuev ,&nbsp;Jan Štefka","doi":"10.1016/j.crpvbd.2025.100319","DOIUrl":"10.1016/j.crpvbd.2025.100319","url":null,"abstract":"<div><div>Monitoring haemosporidian (Genus <em>Plasmodium</em>) infections in passerine birds is essential for understanding the intricate dynamics of avian malaria and its implications for ecology and evolution of avian populations. In this study, we investigated the prevalence and diversity of malaria infections caused by <em>Plasmodium</em> species in three passerine species in Cat-Tien National Park, Vietnam. Using next-generation amplicon sequencing (NGS) of haemosporidian cytochrome <em>b</em> gene, we identified two known and ten novel <em>Plasmodium</em> lineages. Our genetic analysis revealed a high rate of <em>Plasmodium</em> infections in the little spiderhunter (<em>Arachnothera longirostra</em>; Nectariniidae), the white-rumped shama (<em>Copsychus malabaricus</em>; Muscicapidae) and the blue-winged pitta (<em>Pitta moluccensis</em>; Pittidae). Species delimitation methods identified five distinct operational taxonomic units (OTUs), consistently across the majority of the used methods. Each of the passerine species was infected with a specific subset of the total <em>Plasmodium</em> diversity. Phylogenetic analysis showed that sympatric <em>Plasmodium</em> OTUs are not closely related and possess overlapping host preferences. Our findings may reflect differences in habitat use, such as the vertical strata occupied by different bird species, which contribute to varying exposure levels to suitable vectors, thereby influencing infection rates and parasite diversity. Our findings corroborate the view that avian malaria parasites are not uniformly opportunistic; rather, their distribution is filtered by host identity and ecology. Understanding these dynamics is crucial for avian conservation and broader ecological studies, as avian malaria serves as a model for studying parasite-vector-host co-evolution and the impact of environmental changes on disease dynamics.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100319"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145121015","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}

{"title":"Novel zoonotic Enterocytozoon and Encephalitozoon genotypes in domestic pigeons (Columba livia domestica) in Iran: Public health implications","authors":"Alireza Sazmand ,&nbsp;Monireh Khordadmehr ,&nbsp;Zuhal Önder ,&nbsp;Ahmad Oryan ,&nbsp;Farinaz Jigari-Asl ,&nbsp;Farzad Katiraee ,&nbsp;Mehdi Namavari ,&nbsp;Zahra Bahiraei ,&nbsp;Andrew Hemphill ,&nbsp;Domenico Otranto","doi":"10.1016/j.crpvbd.2024.100232","DOIUrl":"10.1016/j.crpvbd.2024.100232","url":null,"abstract":"<div><div>To determine the occurrence of microsporidiosis in domestic pigeons in Iran, privately-owned pigeons presenting weight loss and diarrhea were tested through molecular and histopathological methods. Multiplex-PCR findings showed 57%, 30%, and 14% positivity for <em>Enterocytozoon</em>, <em>Encephalitozoon</em>, and mixed infection in the fecal samples, respectively. A novel <em>Enterocytozoon bieneusi</em> genotype, named IrnEb1, falling into zoonotic group 1 of <em>E. bieneusi</em>, and a novel genotype of <em>Encephalitozoon hellem</em>, named Irn2E, clustering as a sister taxon to genotype 2B were identified in pigeons for the first time using Sanger sequencing and phylogenetic analyses. Histopathological examination revealed the occurrence of non-suppurative enteritis, nephritis, pneumonia, hepatitis, and encephalitis associated with focal necrosis and inflammatory cell infiltration. Data shown herein present a high prevalence of microsporidiosis in pigeons in Iran. Considering that both detected microsporidian species are zoonotic parasites, these findings suggest that the infected pigeons could pose a risk to public health.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100232"},"PeriodicalIF":1.7,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720880","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}

{"title":"Seasonal dynamics, resting behaviour and insecticide susceptibility of Anopheles mosquitoes across two differentially malaria-endemic regions in Ethiopia","authors":"Delelegn Woyessa ,&nbsp;Delenasaw Yewhalaw","doi":"10.1016/j.crpvbd.2024.100224","DOIUrl":"10.1016/j.crpvbd.2024.100224","url":null,"abstract":"<div><div>Information on bionomics of <em>Anopheles</em> species composition, seasonal dynamics and insecticide susceptibility status is important to understand malaria transmission in any particular eco-epidemiological setting and for the design of effective vector control strategies. Here, adult mosquitoes were collected using CDC light traps (CDC LTs) and human landing catches (HLC) for 17 months between June 2018 and September 2020 from Lare District of Ethiopia. Larvae and pupae of anopheline mosquitoes were collected from breeding sites of Lare District and Jimma and reared to adulthood. Bioassays were conducted on non-blood-fed, 3–5-day-old emerged adult female mosquitoes using WHO insecticide-impregnated papers. <em>Plasmodium</em> spp. infection in <em>Anopheles pharoensis</em> and <em>An. coustani</em> were identified using TaqMan qPCR. Of 11,048 <em>Anopheles</em> mosquitoes collected, <em>An. coustani</em> was the most common (46.20%, <em>n</em> = 5103), followed by <em>An. pharoensis</em> (27.89%, <em>n</em> = 3082), <em>An. gambiae</em> (<em>s.l.</em>) (16.04%, <em>n</em> = 1772) and <em>An. funestus</em> (9.88%, <em>n</em> = 1091). Most of the mosquitoes (73.17%, <em>n</em> = 8084) were collected using CDC LTs and 26.83% (<em>n</em> = 2964) were captured using HLC. The mean density of <em>An. gambiae</em>, <em>An. pharoensis</em> and <em>An. coustani</em> was generally higher in June-November as compared to other months during the study period. However, the mean density of <em>An. funestus</em> was relatively higher through November-January following the peak malaria period in Lare. <em>Anopheles pharoensis</em>, <em>An. gambiae</em> (<em>s.l</em>.) and <em>An. coustani</em> complex were susceptible to pirimiphos-methyl, propoxur and bendiocarb. However, <em>An. pharoensis</em> and <em>An. gambiae</em> (<em>s.l.</em>) were resistant to DDT, deltamethrin, permethrin and malathion, whilst members of the <em>An. coustani</em> complex were resistant to DDT and deltamethrin. No <em>Plasmodium</em> spp. infection was detected from samples of <em>Anopheles coustani</em> and <em>An. pharoensis</em>. There was temporal variation in mean density of <em>Anopheles</em> mosquitoes and higher mean mosquito density was recorded during June-November (except for <em>An. funestus</em>). The higher outdoor mean mosquito density coupled with multiple insecticide resistance of malaria vector populations and occurrence of <em>An. funestus</em> in the dry season call for regular monitoring and intervention considering the behavioural dynamics of <em>Anopheles</em> species across seasons.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"6 ","pages":"Article 100224"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660400","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}

{"title":"Filarial disease in the Brazilian Amazon and emerging opportunities for treatment and control","authors":"Cleudecir Siqueira Portela ,&nbsp;Cláudia Patrícia Mendes de Araújo ,&nbsp;Patrícia Moura Sousa ,&nbsp;Carla Letícia Gomes Simão ,&nbsp;João Carlos Silva de Oliveira ,&nbsp;James Lee Crainey","doi":"10.1016/j.crpvbd.2023.100168","DOIUrl":"10.1016/j.crpvbd.2023.100168","url":null,"abstract":"<div><p>Following the successful eradication of <em>Wuchereria bancrofti</em>, there are now just three species of conventional microfilaremic human filarial parasites endemic to the Brazilian Amazon region: <em>Mansonella ozzardi</em>, <em>Mansonella perstans</em> and <em>Onchocerca volvulus.</em> The zoonotic filarial parasite <em>Dirofilaria immitis</em> is also found in the Amazon region as are several sylvatic filarial parasites, some of which have been recorded causing zoonoses and some of which have never been recorded outside the region. <em>Onchocerca volvulus</em> is only found in the Amazonia onchocerciasis focus in the Brazilian state of Roraima where it affects the people of the Yanomami tribe living around the densely forested Venezuela border region. <em>Mansonella ozzardi</em> is by far the most common filarial parasite in Brazil and has a broad but patchy distribution throughout the western Amazon region. Recorded in the Brazilian states of Acre, Roraima, Matto Grosso, and within almost every municipality of Amazonas state, it is believed that pollution of the urban stream and river systems prevents the development of the simuliid vectors of <em>M. ozzardi</em> and explains the parasiteʼs reduced distribution within urban areas and an absence of recent reports from the state capital Manaus. Decades of WHO-led periodic ivermectin treatment of Yanomami tribeʼs people have resulted in the partial suppression of <em>O. volvulus</em> transmission in this focus and has also probably affected the transmission of <em>M. ozzardi</em> in the region. <em>Mansonella perstans</em>, <em>O. volvulus</em> and very probably <em>M. ozzardi</em> infections can all be treated and most likely cured with a 4–6-week treatment course of doxycycline. The Brazilian Ministry of Health does not, however, presently recommend any treatment for mansonellosis infections and thus parasitic infections outside the Amazonia focus are typically left untreated. While the long treatment courses required for doxycycline-based mansonellosis therapies preclude their use in control programmes, new fast-acting filarial drug treatments are likely to soon become available for the treatment of both onchocerciasis and mansonellosis in the Amazon region. Filarial disease management in the Brazilian Amazon is thus likely to become dramatically more viable at a time when the public health importance of these diseases is increasingly being recognized.</p></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"5 ","pages":"Article 100168"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667114X23000560/pdfft?md5=01131ef8399d2fad5247e4829f450f96&pid=1-s2.0-S2667114X23000560-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139194688","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}

{"title":"Spatial and temporal variation of five different pathogens and symbionts in Ixodes ricinus nymphs in the Netherlands","authors":"Nienke Hartemink ,&nbsp;Gerrit Gort ,&nbsp;Aleksandra I. Krawczyk ,&nbsp;Manoj Fonville ,&nbsp;Arnold J.H. van Vliet ,&nbsp;Willem Takken ,&nbsp;Hein Sprong","doi":"10.1016/j.crpvbd.2024.100209","DOIUrl":"10.1016/j.crpvbd.2024.100209","url":null,"abstract":"<div><p>The incidence of diseases caused by pathogens transmitted by the tick <em>Ixodes ricinus</em> vary over time and space through incompletely understood mechanisms. An important determinant of the disease risk is the density of infected ticks, which is the infection prevalence times the density of questing ticks. We therefore investigated the spatial and temporal variation of four pathogens and one of the most abundant symbionts in <em>Ixodes ricinus</em> in questing nymphs over four years of monthly collections in 12 locations in the Netherlands. The infection prevalence of all microbes showed markedly different patterns with significant spatial variation for <em>Borrelia burgdorferi</em> (<em>s.l.</em>), <em>Neoehrlichia mikurensis</em>, <em>Rickettsia helvetica</em>, and <em>Midichloria mitochondrii</em>, significant seasonal variation of <em>B. burgdorferi</em> (<em>s.l.</em>), <em>N. mikurensis</em>, and <em>M. mitochondrii</em> and a significant interannual variation of <em>R. helvetica</em>. Despite its ubiquitous presence, no spatio-temporal variation was observed for the infection prevalence of <em>B. miyamotoi</em>. The variation in infection prevalence was generally smaller than the variation in the density of nymphs, which fluctuated substantially both seasonally and between locations. This means that the variation in the densities of infected nymphs for all pathogens was mostly the result of the variation in densities of nymphs. We also investigated whether there were positive or negative associations between the symbionts, and more specifically whether ticks infected with vertically transmitted symbionts like <em>M. mitochondrii</em> and <em>R. helvetica</em>, have a higher prevalence of horizontally transmitted symbionts, such as <em>B. burgdorferi</em> (<em>s.l.</em>) and <em>N. mikurensis</em>. We indeed found a clear positive association between <em>M. mitochondrii</em> and <em>B. burgdorferi</em> (<em>s.l.</em>). The positive association between <em>R. helvetica</em> and <em>B. burgdorferi</em> (<em>s.l.</em>) was less clear and was only shown in two locations. Additionally, we found a clear positive association between <em>B. burgdorferi</em> (<em>s.l.</em>) and <em>N. mikurensis</em>, which are both transmitted by rodents. Our longitudinal study indicated strong between-location variation, some seasonal patterns and hardly any differences between years for most symbionts. Positive associations between symbionts were observed, suggesting that infection with a (vertically transmitted) symbiont may influence the probability of infection with other symbionts, or that there is a common underlying mechanism (e.g. feeding on rodents).</p></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"6 ","pages":"Article 100209"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667114X24000402/pdfft?md5=475ce81c057fa00593d2b70de9bd4575&pid=1-s2.0-S2667114X24000402-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142157873","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}

{"title":"Diversity of questing ticks and prevalence of tick-associated pathogens in Khao Kheow-Khao Chomphu Wildlife Sanctuary, Chon Buri, Thailand","authors":"Wittawat Wechtaisong ,&nbsp;Chalida Sri-in ,&nbsp;Kritsada Thongmeesee ,&nbsp;Elizabeth Riana ,&nbsp;Thuong Thi Huyen Bui ,&nbsp;Lyric C. Bartholomay ,&nbsp;Sonthaya Tiawsirisup","doi":"10.1016/j.crpvbd.2024.100220","DOIUrl":"10.1016/j.crpvbd.2024.100220","url":null,"abstract":"<div><div>Ixodid ticks are important vectors for tick-borne diseases distributed worldwide, including Thailand. Recreation areas within wildlife habitats are considered high-risk zones for tick exposure and tick-borne disease in humans. The study aimed to determine seasonal variations in tick diversity and pathogen prevalence in Khao Kheow-Khao Chomphu Wildlife Sanctuary, Chon Buri, Thailand. From November 2021 to March 2023, a total of 1331 immature ticks were collected by dragging. The proportion of collected larvae was highest in February 2022, while the number of collected nymphs peaked in December 2021. Seven tick species were molecularly identified: <em>Haemaphysalis lagrangei</em>, <em>H. wellingtoni</em>, <em>H. shimoga</em>, <em>H. obesa</em>, <em>Dermacentor auratus</em>, <em>Rhipicephalus microplu</em>s, and <em>Amblyomma integrum</em>. Of 80 tick pools, <em>Anaplasma</em>, piroplasms (<em>Babesia</em> and <em>Theileria</em>), <em>Bartonella</em>, and <em>Rickettsia</em> were detected in 10% (8/80), 3.75% (3/80), 1.25% (1/80), and 3.75% (3/80) of tick pools, respectively. Phylogenetic analysis grouped the newly generated sequences in the clades of <em>Anaplasma bovis</em>, <em>Babesia gibsoni</em>, <em>Theileria cervi</em>, <em>Bartonella henselae</em>, and <em>Rickettsia montanensis</em>. A seasonal pattern of pathogen appearance was detected during November to February, the cool season in Thailand. Based on our results indicating the highest peak of immature ticks and prevalence of pathogens, visitors should take precautions to avoid tick exposure during this season.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"6 ","pages":"Article 100220"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540134","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}