Parasites & Vectors最新文献

{"title":"Molecular characterisation of common Culicoides biting midges (Diptera: Ceratopogonidae) in Ireland.","authors":"Elsie Isiye, Angela Valcarcel Olmeda, Thomas Curran, David O'Neill, Theo de Waal, Gerald Barry, Aidan O'Hanlon, James O'Shaughnessy, Nicole Keohane McCarthy, Akke Vellinga, Audrey Jenkinson, Alan Johnson, Damien Barrett, Sarah Costello, Annetta Zintl, Denise O'Meara","doi":"10.1186/s13071-025-06754-7","DOIUrl":"https://doi.org/10.1186/s13071-025-06754-7","url":null,"abstract":"<p><strong>Background: </strong>Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) act as vectors for several arboviruses, including bluetongue virus (BTV) and Schmallenberg virus (SBV), which affect livestock health and productivity. In Ireland, limited genetic data are available regarding the diversity of Culicoides species. This study represents the first attempt to characterise Culicoides in this region using molecular techniques.</p><p><strong>Methods: </strong>Adult Culicoides samples were captured using Onderstepoort Veterinary Institute (OVI) traps across six locations in Ireland. Subsequent molecular analyses involved polymerase chain reaction (PCR) and sequencing of the cytochrome oxidase subunit 1 (CO1) and the internal transcriber spacer (ITS) barcoding regions to obtain species identities. In addition, using both markers, we inferred the population genetic structure and potential colonisation pathways of Culicoides obsoletus sensu stricto (s. str.), the major vector species in Ireland.</p><p><strong>Results: </strong>DNA barcoding facilitated identification of 177 specimens. Eight common Culicoides species were identified through DNA barcoding of CO1 and ITS gene regions. The presence of putative vectors of bluetongue virus (BTV) and Schmallenberg virus (SBV) were also confirmed, including species in the subgenus Avaritia (C. obsoletus s. str., C. scoticus, C. chiopterus, and C. dewulfi) and subgenus Culicoides s. str. (C. pulicaris and C. punctatus). Phylogenetic analysis confirmed the relationship between these vector species and facilitated the placement of Culicoides spp. that could not be identified to species level through DNA barcoding. Haplotype network analysis of C. obsoletus showed that some haplotypes of these species are shared between Continental Europe, the UK, and Ireland, suggesting a possible incursion pathway for this vector.</p><p><strong>Conclusions: </strong>DNA barcoding employing a combination of two barcodes, CO1 and ITS, proved effective in identifying Culicoides, especially species within the obsoletus complex, which are difficult to morphologically distinguish. Our findings also suggest that investigation of the population genetic structure of Culicoides spp. could be used to model the potential introduction routes of midge-borne pathogens into the country.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"149"},"PeriodicalIF":3.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12016113/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144037698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Off-grid field-deployable molecular diagnostic platform for malaria surveillance.","authors":"Madhavinadha Prasad Kona, Armel N Tedjou, Mary Kefi, Francesco Buongiorno, Charles S Wondji, George Dimopoulos","doi":"10.1186/s13071-025-06779-y","DOIUrl":"https://doi.org/10.1186/s13071-025-06779-y","url":null,"abstract":"<p><strong>Background: </strong>Malaria, a major global health concern, continues to cause substantial morbidity and mortality, particularly in tropical regions. Traditional malaria diagnostic methods such as microscopy and quantitative polymerase chain reaction (qPCR) are effective but face challenges in field settings because of their requirement for laboratories with specialized equipment and trained personnel. This study presents the development and validation of a portable, cost-effective, field-deployable real-time qPCR platform for detecting Plasmodium species.</p><p><strong>Methods: </strong>Field-compatible DNA isolation was performed using DNAzol, and TaqMan probes targeting 18S ribosomal RNA (rRNA) were employed to detect five Plasmodium species-P. falciparum, P. vivax, P. malariae, P. ovale, and P. knowlesi-using the bCUBE qPCR platform. In vitro-cultured P. falciparum and experimentally infected Anopheles gambiae were used to quantify P. falciparum infections, with infection prevalence compared to microscopy. The bCUBE qPCR system was also evaluated under field conditions to detect P. falciparum infections in field-collected An. gambiae mosquitoes.</p><p><strong>Results: </strong>The bCUBE qPCR demonstrated a strong linear correlation (R² = 0.993) with a standard laboratory qPCR machine for detecting P. falciparum infections. It successfully detected as few as 0.5 parasites/µl of blood, one oocyst in mosquito guts, and 5-10 sporozoites in salivary glands. It was also capable of discriminating between P. falciparum, P. vivax, P. malariae, P. ovale, and P. knowlesi. Field evaluations in Cameroon confirmed its accuracy in identifying P. falciparum in mosquito samples, with same-day results. The capability of the bCUBE qPCR system to detect infections in both individual and pooled mosquito surveillance further highlights its potential for in-field large-scale malaria monitoring surveillance.</p><p><strong>Conclusions: </strong>The bCUBE qPCR system offers a portable, sensitive, and scalable solution for malaria diagnostics, enabling real-time surveillance in resource-limited settings. Its ability to provide rapid, on-site results reduces the need for centralized laboratory testing, facilitating timely decision-making in malaria control programs.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"150"},"PeriodicalIF":3.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12016468/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144014641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasmodium cynomolgi: potential emergence of new zoonotic malaria in Southeast Asia.","authors":"Nantha Kumar Jeyaprakasam, Wei Kit Phang, Shahhaziq Shahari, Indra Vythilingam","doi":"10.1186/s13071-025-06784-1","DOIUrl":"https://doi.org/10.1186/s13071-025-06784-1","url":null,"abstract":"<p><p>The reported cases of Plasmodium cynomolgi in Southeast Asia pose a significant public health concern. Sporadic reports of human Plasmodium cynomolgi infections have increased in the past few years, raising attention regarding its potential impact on human populations. Further compounding this issue are the morphological similarities between P. cynomolgi and the human malaria parasite Plasmodium vivax, which may lead to misdiagnosis and underreporting of P. cynomolgi infections. Both in vitro and in vivo studies have shown that P. cynomolgi can effectively invade human reticulocytes using mechanisms like those employed by P. vivax, underscoring its capacity to infect human hosts if given the opportunity. These studies collectively highlight the parasite's potential to establish infections in humans and emphasize the need for molecular diagnostic tools to accurately detect P. cynomolgi. Additionally, challenges in accurate diagnosis and surveillance systems may underestimate the true extent of their impact, making it imperative for healthcare authorities to bolster monitoring efforts and deploy targeted interventions. Strengthening surveillance, improving diagnostic capabilities, and developing targeted vector control strategies are crucial to mitigating the risk of P. cynomolgi becoming a major zoonotic disease like its counterpart, Plasmodium knowlesi. Thus, this review aims to highlight the current understanding of P. cynomolgi infections in human, vector, and macaque hosts based on collated data from previous studies while underscoring the urgent need for enhanced surveillance, accurate diagnostic tools, and effective vector control strategies to mitigate its potential as a significant zoonotic threat in Southeast Asia.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"151"},"PeriodicalIF":3.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12020267/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144037118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the 2022 West Nile virus forecasting challenge, USA.","authors":"Ryan D Harp, Karen M Holcomb, Renata Retkute, Alisa Prusokiene, Augustinas Prusokas, Zeynep Ertem, Marco Ajelli, Allisandra G Kummer, Maria Litvinova, Stefano Merler, Ana Pastore Y Piontti, Piero Poletti, Alessandro Vespignani, Andre B B Wilke, Agnese Zardini, Kelly Helm Smith, Philip Armstrong, Nicholas DeFelice, Alexander Keyel, John Shepard, Rebecca Smith, Andrew Tyre, John Humphreys, Lee W Cohnstaedt, Saman Hosseini, Caterina Scoglio, Morgan E Gorris, Martha Barnard, S Kane Moser, Julie A Spencer, Maggie S J McCarter, Christopher Lee, Melissa S Nolan, Christopher M Barker, J Erin Staples, Randall J Nett, Michael A Johansson","doi":"10.1186/s13071-025-06767-2","DOIUrl":"https://doi.org/10.1186/s13071-025-06767-2","url":null,"abstract":"<p><strong>Background: </strong>West Nile virus (WNV) is the most common cause of mosquito-borne disease in the continental USA, with an average of ~1200 severe, neuroinvasive cases reported annually from 2005 to 2021 (range 386-2873). Despite this burden, efforts to forecast WNV disease to inform public health measures to reduce disease incidence have had limited success. Here, we analyze forecasts submitted to the 2022 WNV Forecasting Challenge, a follow-up to the 2020 WNV Forecasting Challenge.</p><p><strong>Methods: </strong>Forecasting teams submitted probabilistic forecasts of annual West Nile virus neuroinvasive disease (WNND) cases for each county in the continental USA for the 2022 WNV season. We assessed the skill of team-specific forecasts, baseline forecasts, and an ensemble created from team-specific forecasts. We then characterized the impact of model characteristics and county-specific contextual factors (e.g., population) on forecast skill.</p><p><strong>Results: </strong>Ensemble forecasts for 2022 anticipated a season at or below median long-term WNND incidence for nearly all (> 99%) counties. More counties reported higher case numbers than anticipated by the ensemble forecast median, but national caseload (826) was well below the 10-year median (1386). Forecast skill was highest for the ensemble forecast, though the historical negative binomial baseline model and several team-submitted forecasts had similar forecast skill. Forecasts utilizing regression-based frameworks tended to have more skill than those that did not and models using climate, mosquito surveillance, demographic, or avian data had less skill than those that did not, potentially due to overfitting. County-contextual analysis showed strong relationships with the number of years that WNND had been reported and permutation entropy (historical variability). Evaluations based on weighted interval score and logarithmic scoring metrics produced similar results.</p><p><strong>Conclusions: </strong>The relative success of the ensemble forecast, the best forecast for 2022, suggests potential gains in community ability to forecast WNV, an improvement from the 2020 Challenge. Similar to the previous challenge, however, our results indicate that skill was still limited with general underprediction despite a relative low incidence year. Potential opportunities for improvement include refining mechanistic approaches, integrating additional data sources, and considering different approaches for areas with and without previous cases.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"152"},"PeriodicalIF":3.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12020065/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144049202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Safety of Credelio Quattro™ (lotilaner, moxidectin, praziquantel, and pyrantel chewable tablets) in homozygous MDR1-mutant collie dogs.","authors":"Kari L Riggs, Xinshuo Wang, Scott Wiseman","doi":"10.1186/s13071-025-06795-y","DOIUrl":"https://doi.org/10.1186/s13071-025-06795-y","url":null,"abstract":"<p><strong>Background: </strong>Multidrug resistance-1 (MDR1) mutant dogs have diminished or lack P-glycoprotein (Pgp) expression at the blood-brain barrier and are therefore more susceptible to neurotoxicity caused by macrocyclic lactones and other Pgp substrates due to increased drug penetration into the brain. Therefore, the safety of products containing macrocyclic lactones are required to be evaluated in this sensitive population. Credelio Quattro (lotilaner, moxidectin, praziquantel, and pyrantel chewable tablets) is a novel endectocide for monthly oral administration in dogs. As moxidectin is a macrocyclic lactone, Credelio Quattro was administered to homozygous MDR1 mutant Collie dogs to evaluate the safety of the product.</p><p><strong>Methods: </strong>The study employed a completely randomized and blinded design, where dogs were allocated to one of four treatment groups. A total of 32 dogs were divided into 4 groups (placebo control, 1×, 2×, or 5×, the maximum recommended labeled dose of Credelio Quattro) each consisting of 8 dogs. Treatment was administered on 3 consecutive occasions, 28 days apart. Dogs were evaluated pre-dose and through 72-h post-treatment using the avermectin sensitive (AVS) categories of seizures or convulsions, ataxia, depression, mydriasis, muscle tremors, and salivation/drooling/vomiting. The assessment of safety was based on AVS scores, general health observations, body weight, and physical examinations.</p><p><strong>Results: </strong>Credelio Quattro was well tolerated with no serious adverse events. There were no incidents of seizures or convulsions, ataxia, mydriasis, or muscle tremors observed. Salivation/drooling/vomiting was the most frequent observation, occurring in all groups, and most frequently in the 5× group. Vomiting is a dose-dependent effect observed for Credelio Quattro in healthy dogs and is therefore unlikely to represent a neurological effect in MDR1 dogs. Depression was observed in one dog in each of the 0×, 2×, and 5× groups. This was likely a spurious result versus true toxicity, as the sign was subtle and occurred singularly including at 0×. For all AVS signs, the events were transient, and dogs recovered without any intervention.</p><p><strong>Conclusions: </strong>Credelio Quattro was well tolerated and is safe in MDR1 mutant dogs up to 5× the maximum recommended dose following three consecutive monthly administrations.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"153"},"PeriodicalIF":3.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12020015/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144030710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The ability of an oral combination of afoxolaner, moxidectin and pyrantel to protect dogs from Borrelia burgdorferi infections transmitted by Ixodes scapularis.","authors":"Joseph Prullage, Pascal Dumont, Arathy Nair, Manyun Liu, Utami DiCosty, Ricarda Süssenberger","doi":"10.1186/s13071-025-06753-8","DOIUrl":"https://doi.org/10.1186/s13071-025-06753-8","url":null,"abstract":"<p><strong>Background: </strong>Two studies were conducted to determine whether treatment with NexGard^® Plus (NP), a combination of afoxolaner, moxidectin, and pyrantel, prevents transmission of Borrelia burgdorferi to dogs by naturally infected Ixodes scapularis.</p><p><strong>Methods: </strong>For each study, 20 dogs were randomly assigned to two groups (n = 10/group): NP and negative control. Twenty-eight days post-treatment, each dog was infested with approximately 50 I. scapularis that had a 60% B. burgdorferi infection rate in study 1 and a 38.5% infection rate in study 2. Five days post-infestation, ticks were counted and removed. The B. burgdorferi-specific C6 antibody was tested for using the SNAP^® 4Dx^® test (IDEXX) and the Lyme Quant C6 test with serum collected before treatment and infestation and 21, 35, 49, 63, and 75 days post-infestation. Skin biopsies were collected 76 days post-infestation and quantitative polymerase chain reaction (qPCR) conducted to detect B. burgdorferi DNA.</p><p><strong>Results: </strong>On the day of count and removal, no ticks were found on treated dogs, while control dogs had an average of 25.1 ticks in study 1 and 19.6 ticks in study 2, for efficacy of 100% (P ≤ 0.0001). All dogs were seronegative before infestation. The first dog in the control groups became seropositive 21 days post-infestation in study 1 and 35 days post-infestation in study 2 by the SNAP 4Dx test and by 21 days post-infestation by the Lyme Quant C6 test in both studies. Ten of 10 dogs in the control group in both studies seroconverted by the end of the study. None of the skin biopsies from treated dogs were positive for B. burgdorferi DNA, while at least three of the four skin biopsies from each of the control dogs tested positive at the end of the studies. No clinical signs of Lyme disease were detected in any of the dogs.</p><p><strong>Conclusions: </strong>The results of these studies indicate that NexGard^® Plus administered at a dose close to the minimum recommended dose of 2.5 mg/kg afoxolaner is effective 28 days after a single treatment in the prevention of B. burgdorferi transmission from naturally infected I. scapularis ticks to dogs.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"147"},"PeriodicalIF":3.0,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12010565/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does washing insecticide-treated nets 20 times for experimental hut evaluations provide a suitable proxy for their end-of-life performance under household conditions?","authors":"Thomas Syme, Abel Agbevo, Josias Fagbohoun, Boris N'dombidjé, Judicael Nounagnon, Juniace Ahoga, Joël Akpi, Corine Ngufor","doi":"10.1186/s13071-025-06743-w","DOIUrl":"https://doi.org/10.1186/s13071-025-06743-w","url":null,"abstract":"<p><strong>Background: </strong>Insecticide-treated nets (ITNs) are washed 20 times as part of experimental hut trials to simulate the loss of active ingredient (AI) occurring over their intended 3-year lifespan and estimate insecticidal durability. The ability of the 20-wash method to predict the end-of-life performance of ITNs has not been empirically validated.</p><p><strong>Methods: </strong>We performed an experimental hut trial to compare the efficacy of new ITNs unwashed and washed 20 times to field-aged ITNs withdrawn from households 3 years post-distribution against a pyrethroid-resistant vector population in Covè, Benin. Four products from pyrethroid-only (Interceptor^®), pyrethroid-piperonyl butoxide (PermaNet^® 3.0), pyrethroid-pyriproxyfen (Royal Guard^®) and pyrethroid-chlorfenapyr (Interceptor^® G2) ITN types were tested. Net pieces were tested in bioassays and sent for chemical analysis to assess differences in surface AI bioavailability and total chemical content between washed and field-aged nets. Susceptibility bioassays were also performed to assess insecticide resistance in the Covè vector population.</p><p><strong>Results: </strong>Mosquito mortality in experimental huts was similar or slightly higher with field-aged nets than washed nets with Interceptor^® (11% vs. 10%, p = 0.339, OR = 1.19, 95% CIs [0.84, 1.69]), PermaNet^® 3.0 (12% vs. 18%, p < 0.001, OR = 1.78, 95% CIs [1.34, 2.38]) and Royal Guard^® (9% vs. 14%, p = 0.076, OR = 1.33, 95% CIs: [0.97, 1.83]). Likewise, field-aged Royal Guard^® induced a similar reduction in fertility to washed Royal Guard^® (22% vs. 29%, p = 0.066). In contrast, mortality was significantly lower with field-aged nets Interceptor^® G2 compared to washed nets (54% vs. 19%, p < 0.001, OR = 0.18, 95% CIs [0.14, 0.24]). Blood-feeding inhibition was higher with field-aged nets than washed nets across all ITN types. Retention of non-pyrethroid AIs was lower than for the pyrethroid, particularly with field-aged nets (PermaNet^® 3.0 (roof): 25% vs. 68%, p < 0.001, Royal Guard^®: 27% vs. 53%, p < 0.001, Interceptor^® G2: 14% vs. 39%, p < 0.001).</p><p><strong>Conclusions: </strong>In this setting, the 20-wash method provided a suitable proxy for the end-of-life killing and sterilising performance of Interceptor^®, PermaNet^® 3.0 and Royal Guard® in experimental huts. In contrast, washing overestimated the end-of-life performance of Interceptor^® G2 for mortality and underestimated the personal protection of all field-aged ITNs.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"148"},"PeriodicalIF":3.0,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12010526/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144005163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling the relationships between midge abundance and incidence, microbial communities, and soil and water properties in a protected natural tallgrass prairie.","authors":"Saraswoti Neupane, Travis Davis, Cassandra Olds, Dana Nayduch, Bethany L McGregor","doi":"10.1186/s13071-025-06780-5","DOIUrl":"https://doi.org/10.1186/s13071-025-06780-5","url":null,"abstract":"<p><strong>Background: </strong>Biting midges (Culicoides spp.) are small blood-feeding flies (Diptera: Ceratopogonidae) that transmit numerous pathogens that impact animal and human health. The larvae of several Culicoides spp., including vectors, are often found in organically enriched, moist soil habitats. However, the influence of biotic (e.g., cohabiting fauna, potential prey taxa) and abiotic factors (e.g., soil or water properties, time) on abundance and incidence of larval Culicoides in natural habitats is not well understood. This study evaluated the relationships between bacterial and protistan communities, soil and water physicochemical properties, and the abundance and incidence of Culicoides species in larval habitats at the Konza Prairie Biological Station in Kansas.</p><p><strong>Methods: </strong>Soil and water samples were collected monthly from March 2021 to February 2022 from four midge larval habitat sites, including three grazed (low-production cattle-grazed (LPCG), high-production cattle-grazed (HPCG), and bison-grazed sites) and one formally ungrazed (i.e., no managed large mammals) site. Midge incidence and abundance were evaluated using emergence assays, which assessed the number of adults emerging from collected soil samples, and bacterial and protistan communities in these samples were characterized through amplicon sequencing of the 16S and 18S rRNA genes. Physicochemical properties of water and soil were also analyzed.</p><p><strong>Results: </strong>Irrespective of site, the highest midge abundance was reported in warmer months between March and September, except June. Moreover, the greatest midge abundance, incidence, and prevalence occurred at the HPCG and bison-grazed sites, which had a persistent water source. Specific lineages of bacterial and protistan communities, soil texture, organic matter, and total dissolved solids in water samples were directly associated with the abundance of Culicoides spp. that emerged from soil samples.</p><p><strong>Conclusions: </strong>Both biotic (bacterial and protistan communities, presence of host animals), and abiotic (soil and water properties, season) factors affected the abundance and incidence of Culicoides spp. in natural habitats. The results presented in this study expand our understanding of the ecological and environmental factors influencing larval ecology of biting midges in natural developmental substrates. These insights have important implications for identifying potential developmental sites, which can be used for targeted management of Culicoides.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"146"},"PeriodicalIF":3.0,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12009528/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are you ready for the tick season? Spring dynamic of tick diversity and density in urban and suburban areas.","authors":"Dagmara Wężyk, Dorota Dwużnik-Szarek, Maciej Kowalec, Szymon Biela, Kajetan Biernacki, Adrian Macion, Zofia Mencwel, Natalia Safarzynska, Liliana Sajnok, Weronika Słomka, Anna Bajer","doi":"10.1186/s13071-025-06793-0","DOIUrl":"https://doi.org/10.1186/s13071-025-06793-0","url":null,"abstract":"<p><strong>Background: </strong>Occurrence of tick-borne diseases (TBD) is often seasonal and associated with seasonal activity of appropriate tick vectors. As seasonal activity of ticks differs, the risk of contracting particular TBD should change between and within seasons. It is of key importance to monitor seasonal dynamic of tick vectors, especially in human-associated habitats. The aim of the current study was to compare activity and density of Ixodes ricinus and Dermacentor reticulatus during spring season in urban and suburban habitats.</p><p><strong>Methods: </strong>Systematic tick collection by dragging was performed every 1-2 weeks between mid-March and mid-June 2021 at 15 sites: 6 in Warsaw (urban areas) and 9 in suburban areas.</p><p><strong>Results: </strong>During 178 field collections of ticks, including 131 collections from urban sites and 47 collections from rural areas, 738 ticks (385 adult D. reticulatus and 353 I. ricinus) were collected. Dermacentor reticulatus ticks are found from the beginning of spring, peaking in April and May, and I. ricinus ticks are present from early April, peaking in April and May as well. I. ricinus were abundant in rural and urban areas, including botanical garden and forest kindergarten area. Dermacentor reticulatus were found in urban fallow lands but were not collected in parks. These ticks were abundant in fallow lands, meadow, and mixed forest. DNA of B. burgdorferi s.l. and Rickettsia spp. was identified in ticks from urban areas.</p><p><strong>Conclusions: </strong>Due to the marked differences in spring dynamic of D. reticulatus and I. ricinus, the sampling effort should be repeated at least three times per season for accurate estimation of tick occurrence (presence/absence) and density. Due to \"exchange\" of tick species, total tick density remains high through the spring season of activity, which may result in high transmission of tick-borne pathogens (TBPs). Tick densities are dependent on the habitat type and may be low in well-managed agricultural habitats (crop fields, pastures, chicken yard), but high in semi-natural habitats (fallow lands, rural forests). Numerous I. ricinus populations can be maintained in urban green areas such as botanical gardens. Ticks from urban areas can serve as vectors of important TBPs (B. burgdorferi s.l., Rickettsia spp.).</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"144"},"PeriodicalIF":3.0,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12009520/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144026779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tick-borne agents in the fowl tick Argas persicus from northwest and northeast China.","authors":"Junhua Tian, Jing Liu, Kun Li, Li Zhong, Miao Lu, Hai Jiang, Runda Jie, Xiao Wang, Bing Zhang","doi":"10.1186/s13071-025-06750-x","DOIUrl":"https://doi.org/10.1186/s13071-025-06750-x","url":null,"abstract":"<p><p>Although tick-borne agents have been extensively studied, etiological investigations on soft ticks are still relatively rare. In this study, we collected 114 Argas persicus ticks from two provinces (Xinjiang and Heilongjiang) located in northwest and northeast China, respectively, and screened them for tick-borne agents. Two Rickettsia species were identified in A. persicus ticks from Heilongjiang Province: Rickettsia hoogstraalii (27.3%, 18/66) and a previously unidentified species (12.2%, 8/66). The 16S rDNA, gltA, groEL, and ompB genes of the latter have 98.8%, 93.1%, 94.3%, and 91.2% nucleotide identities to reported species, suggesting that it represents a novel species. It belongs to the ancient group of Rickettsia and is located in the basal position of the phylogenetic trees. Additionally, Coxiella endosymbiont was detected in A. persicus ticks from both locations with 100% positive rates. Furthermore, the Coxiella endosymbionts from different locations form distinct phylogenetic groups, indicating that one tick species can harbor different Coxiella endosymbionts.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"145"},"PeriodicalIF":3.0,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12009524/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}