Parasites & Vectors最新文献

{"title":"Diagnostic dilemma: application of real-time PCR assays for the detection of Dientamoeba fragilis in medical and veterinary specimens.","authors":"Luke M Hall, John T Ellis, Damien J Stark","doi":"10.1186/s13071-025-06730-1","DOIUrl":"10.1186/s13071-025-06730-1","url":null,"abstract":"<p><strong>Background: </strong>Real-time PCR (qPCR) diagnostics developed for use in human clinical settings have been implemented to identify new animal hosts of the gastrointestinal protozoan Dientamoeba fragilis. The gut microbiome varies between species; unrecognised cross-reactivity could occur when applying these assays to new animal hosts. The use of qPCR diagnostics was assessed for the identification of new animal hosts of the gastrointestinal protozoan Dientamoeba fragilis.</p><p><strong>Methods: </strong>Forty-nine cattle, 84 dogs, 39 cats and 254 humans were screened for D. fragilis using two qPCR assays: EasyScreen (Genetic Signatures) and a laboratory-based assay commonly used in Europe. The reliability of the identifications made by these assays were assessed using melt curve analysis of qPCR products, conventional PCR targeting the SSU rDNA sequencing and NGS amplicon sequencing of qPCR product.</p><p><strong>Results: </strong>PCR products from the D. fragilis identified in cattle had a 9 °C cooler melt curve than when detected in humans. This melt curve discrepancy, indicative of cross-reactivity with an unknown organism, was investigated further. DNA sequencing determined that Simplicimonas sp. was the genera responsible for this cross-reactivity in cattle specimens. Dientamoeba fragilis was not detected in either dogs or cats. There was a discrepancy in the number of positive samples detected using the two qPCR assays when applied to human samples. The EasyScreen assay detected 24 positive samples; the laboratory-based assay detected an additional 34 positive samples. Of the discrepant samples, 5 returned sequence data for D. fragilis, and 29 were unsupported (false) positive samples.</p><p><strong>Conclusions: </strong>Analysis of the melt curve after the qPCR reaction is a valuable technique to help differentiate samples containing D. fragilis compared to cross-reactions with non-target organisms. The identification of new animal hosts requires further evidence from either microscopy or DNA sequencing to confirm the presence of D. fragilis. Additionally, to reduce the risk of false-positive results due to non-specific amplification, we recommend reducing the number of PCR cycles to less than 40. Based on these results, we consider the ramifications of this identified cross-reactivity to the known host species distribution of D. fragilis.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"94"},"PeriodicalIF":3.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11889766/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586532","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":"Bird-tick and human-tick encounters in the Rio Grande Valley (Texas, USA): ecological associations and pathogen detections.","authors":"Julia Gonzalez, Mark Conway, Sarah A Hamer","doi":"10.1186/s13071-025-06725-y","DOIUrl":"10.1186/s13071-025-06725-y","url":null,"abstract":"<p><strong>Background: </strong>The tropical climate and diverse vector community allows the Rio Grande Valley (RGV) of South Texas to support many vector-borne pathogen transmission cycles. It is a key area for monitoring bird ticks, since most of the migratory birds fly through this corridor to move for south tropical latitudes. Some of the tick species that infest birds in Texas can also transmit tick-borne pathogens that concern public health.</p><p><strong>Methods: </strong>During bird banding activities in 2019-2024, ticks were collected opportunistically from local and migrant birds, as well as from outdoor recreationalists, to explore the presence of tick-borne pathogens. Applying a polymerase chain reaction (PCR)-DNA sequencing approach, ticks were tested for Ehrlichia and Rickettsia species.</p><p><strong>Results: </strong>Of 375 ticks, eight tick species were identified, including species regarded as locally established (Amblyomma inornatum, Amblyomma maculatum, Amblyomma mixtum, Amblyomma tenellum, and Dermacentor variabilis), neotropical species imported by migratory birds (Amblyomma geayi and Amblyomma longirostre), and for the first time in Texas, Ixodes keiransi, formerly the North American lineage of Ixodes affinis. Amblyomma tenellum was the most abundant tick species (89.3%). All ticks were screened for Ehrlichia, resulting in Ehrlichia chaffeensis detection in three A. tenellum ticks (one nymph and two adults) found on humans, and one positive for Ehrlichia ewingii in an A. inornatum nymph collected from a Clay-colored Thrush (Turdus grayi). Both bacteria can cause human ehrlichiosis, which is infrequently reported in Texas. The Rickettsia screening of ticks resulted in detection of Rickettsia amblyommatis, a potentially pathogenic spotted fever group Rickettsia, in nine ticks: eight A. inornatum ticks (one larva, five nymphs and two adults), seven of which were collected from Long-billed Thrashers (Toxostoma longirostre); and an A. longirostre engorged nymph from an Acadian Flycatcher (Empidonax virescens).</p><p><strong>Conclusions: </strong>Our results highlight the importance of occupational exposure to ticks and the potential public health impact of the relatively neglected human-biting vector, A. tenellum.. There is also a critical need to investigate the fate of bird-imported A. inornatum and A. longirostre, and the pathogens they carry.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"95"},"PeriodicalIF":3.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11889838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586478","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":"Comparison of unmanned aerial vehicle imaging to ground truth walkthroughs for identifying and classifying trash sites serving as potential Aedes aegypti breeding grounds.","authors":"Morgan S Tarpenning, Juliet T Bramante, Kavita D Coombe, Katherine E Woo, Andrew J Chamberlin, Paul S Mutuku, Giulio A De Leo, Angelle Desiree LaBeaud, Bryson A Ndenga, Francis M Mutuku, Joelle I Rosser","doi":"10.1186/s13071-025-06706-1","DOIUrl":"10.1186/s13071-025-06706-1","url":null,"abstract":"<p><strong>Background: </strong>Trash piles and abandoned tires that are exposed to the elements collect water and create productive breeding grounds for Aedes aegypti mosquitoes, the primary vector for multiple arboviruses. Unmanned aerial vehicle (UAV) imaging provides a novel approach to efficiently and accurately mapping trash, which could facilitate improved prediction of Ae. aegypti habitat and consequent arbovirus transmission. This study evaluates the efficacy of trash identification by UAV imaging analysis compared with the standard practice of walking through a community to count and classify trash piles.</p><p><strong>Methods: </strong>We conducted UAV flights and four types of walkthrough trash surveys in the city of Kisumu and town of Ukunda in western and coastal Kenya, respectively. Trash was classified on the basis of a scheme previously developed to identify high and low risk Aedes aegypti breeding sites. We then compared trash detection between the UAV images and walkthrough surveys.</p><p><strong>Results: </strong>Across all walkthrough methods, UAV image analysis captured 1.8-fold to 4.4-fold more trash than the walkthrough method alone. Ground truth validation of UAV-identified trash showed that 94% of the labeled trash sites were correctly identified with regards to both location and trash classification. In addition, 98% of the visible trash mimics documented during walkthroughs were correctly avoided during UAV image analysis. We identified advantages and limitations to using UAV imaging to identify trash piles. While UAV imaging did miss trash underneath vegetation or buildings and did not show the exact composition of trash piles, this method was efficient, enabled detailed quantitative trash data, and granted access to areas that were not easily accessible by walking.</p><p><strong>Conclusions: </strong>UAVs provide a promising method of trash mapping and classification, which can improve research evaluating trash as a risk factor for infectious diseases or aiming to decrease community trash exposure.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"93"},"PeriodicalIF":3.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883972/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143573595","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":"Morphofunctional characteristics of flight-related traits in deltamethrin-resistant and susceptible Triatoma infestans (Klug, 1834) of the Argentinean Chaco.","authors":"Víctor A Maza, M Victoria Cardinal, Julieta Nattero","doi":"10.1186/s13071-025-06678-2","DOIUrl":"10.1186/s13071-025-06678-2","url":null,"abstract":"<p><strong>Background: </strong>Chagas disease, transmitted by triatomine bugs, is a major vector-borne parasitic disease in Latin America. Triatoma infestans, the principal vector in the Southern Cone, is primarily controlled through residual insecticide spraying. However, resistance to pyrethroids, especially in Northern Argentina and Southern Bolivia, has emerged. Resistant T. infestans populations exhibit reduced fitness, including impacts on reproductive success and dispersal capacity. This study investigates the flight potential and morphological changes in T. infestans populations with varying levels of insecticide resistance, hypothesizing that resistance may induce morphological changes in wing and head structures related to dispersal.</p><p><strong>Methods: </strong>We analyzed three resistance profiles of T. infestans-susceptible (S), moderately resistant (MR), and highly resistant (HR)-collected from ten domestic or peridomestic sites in two municipalities from Chaco province, Argentina. We registered flight muscle development and measured flight-related traits (wings, heads, and the stiff and membranous portions of the wing) using a landmark-based methodology. We also assessed morphological disparity and covariation of these traits across toxicological groups.</p><p><strong>Results: </strong>Significant morphological differences were found between resistant and susceptible populations. The frequency of insects with and without muscle varied across toxicological groups only for females, exhibiting the highest proportion of HR insects with fight muscle (86.21%). MR and HR males exhibited smaller stiff portions of the wing and heads than S males. Shape variation analysis showed that S females had wider forewings than resistant females, while HR females had narrower wings with a wider stiff portion. Susceptible males had wider and longer wings compared with resistant groups. Additionally, resistant populations showed greater morphological disparity and reduced covariation between flight-related traits.</p><p><strong>Conclusions: </strong>Our study shows that pyrethroid resistance in T. infestans is linked to morphological changes in flight-related traits. These changes suggest a tradeoff between resistance and flight capacity, with energy allocated to resistance mechanisms potentially limiting flight. The reduced covariation between flight traits in resistant individuals supports the idea of pleiotropic effects. While resistant individuals may perform better in insecticide treated areas, their reduced flight capacity could limit long-distance dispersal, affecting population dynamics and vector control efforts.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"92"},"PeriodicalIF":3.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883966/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567840","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":"Local investigation into the role of Culicoides species diversity (Diptera: Ceratopogonidae) in recurrent horse dermatitis cases in southwest France.","authors":"Jorian Prudhomme, Clara Bardet, Ignace Rakotoarivony, Claire Garros, Émilie Bouhsira, Emmanuel Lienard","doi":"10.1186/s13071-025-06694-2","DOIUrl":"10.1186/s13071-025-06694-2","url":null,"abstract":"<p><strong>Background: </strong>Insect bite hypersensitivity in horses (\"sweet itch\") is a common pruritic, chronic, seasonal, and recurrent dermatitis affecting approximately 10% of horses in France and is a major concern for the horse industry and private owners. This dermatitis results from an allergic reaction to the saliva of specific biting flies (Diptera: Nematocera), primarily from the Culicoides genus. Given the frequent occurrence of this health problem and the limited investigation in France, we conducted a field survey in the vicinity of a riding stable in southwestern France with a reported chronic case of recurrent horse dermatitis to (i) characterize the Culicoides species associated with horse populations and (ii) estimate the relative abundance of the different species identified based on the trapping site location.</p><p><strong>Methods: </strong>For this purpose, three Onderstepoort Veterinary Institute (OVI) traps were set up for one night once a week, from mid-June to the end of July 2022, the known adult peak activity period. Traps were placed either indoors or outdoors at horse facilities.</p><p><strong>Results: </strong>Culicoides obsoletus/scoticus were more abundant (58.3%), followed by C. circumscriptus (12.1%), C. nubeculosus (11.5%), C. punctatus (5.6%), C. festivipennis (3.8%), C. pulicaris (2.3%), C. riethi (2.3%), C. parroti (2.2%), and the remaining species, C. lupicaris, C. dewulfi, C. brunnicans, C. flavipulicaris, and C. picturatus, collectively representing only 1.4%. Importantly, C. obsoletus/scoticus and C. circumscriptus were found indoors in notable proportions (54% and 11.4% of captures, respectively).</p><p><strong>Conclusions: </strong>The findings highlight the continuous exposure of horses to Culicoides bites during the warm season, including at night and indoors, from C. obsoletus/scoticus, but also including low-impact species like C. punctatus and C. pulicaris. This underlines the need for ongoing research and surveillance.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"86"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11881243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567839","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":"Integrative taxonomy in helminth analysis: protocols and limitations in the twenty-first century.","authors":"Alicia Rojas, Laura G Bass, Josué Campos-Camacho, Fernando A Dittel-Meza, Cristian Fonseca, Ying Yi Huang-Qiu, Roberto W I Olivares, Luis M Romero-Vega, Fabián Villegas-Rojas, Alberto Solano-Barquero","doi":"10.1186/s13071-025-06682-6","DOIUrl":"10.1186/s13071-025-06682-6","url":null,"abstract":"<p><p>The term integrative taxonomy was coined in 2005 for the identification of microorganisms using morphological, molecular, pathological and ecological components. Since then, more than 200 scientific articles have been published using this term in the helminthology field in different geographical regions of the world, leading to accurate identifications of specimens and expanding the known biodiversity by describing novel species. Importantly, the responsible use of this approach has led to balanced results in which molecular data do not overshadow morphological, pathological or ecological information. By having different perspectives, new taxonomic situations have arrived including the definition of cryptic diversity, species complex and genotypes. In the present work, we present the main procedures and principles for conducting an integrative taxonomy study of parasitic helminth including collection and preservation of specimens, fixation and staining of worms for light microscopy and scanning electron microscopy, and histopathological, ecological and DNA analysis. This guide is aimed at researchers in their endeavor to analyze helminth parasites collected from wild or domestic animals with examples provided, but the protocols presented herein may be extrapolated for the analysis of helminths collected from other hosts (e.g. human or fish). One important aspect is that the recommendations presented herein derive from the authors' experiences, which will hopefully be of use to the reader.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"87"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11881375/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567731","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":"A pilot investigation of bovine schistosomiasis on Unguja Island, Zanzibar, raises a new concern for elimination of urogenital schistosomiasis.","authors":"Shaali Ame, Othman Juma, Alexandra Juhász, Mtumweni Ali, Talib S Suleiman, Geoffrey N Gobert, Lucas J Cunningham, Abigail Cawley, Lilly Atkins, Sam Jones, E James LaCourse, Fatma Kabole, J Russell Stothard","doi":"10.1186/s13071-025-06698-y","DOIUrl":"10.1186/s13071-025-06698-y","url":null,"abstract":"<p><p>Our pilot parasitological investigation of cattle, supplemented with molecular DNA characterisation of encountered schistosomes, sheds first light upon bovine schistosomiasis on Unguja Island, Zanzibar. During February 2024, a total of 99 cattle were examined. Of these, 47 were exported animals from the Tanzanian mainland, designated for slaughter at two governmental abattoirs (Kisakasaka and Muwanda), and 52 were free-grazing animals sampled from four grazing locations within the island's North and West-B regions. Upon visual inspection of 31 cattle carcasses at Kisakasaka for adult worms, the prevalence of bovine schistosomiasis was 51.6%; however, upon faecal miracidia hatching test (MHT) it was 80.6%. At Muwanda, only faecal MHT was used, finding a much lower prevalence of 12.5%. In free-grazing animals, the prevalence of bovine schistosomiasis by MHT was 0.0%. At Muwanda, the animal quarantine paddock was in disrepair, inclusive of a large pond now acting as a watering point. Here, numerous Bulinus forskalii sp. were found. Whilst no snails were observed to shed schistosome cercariae, molecular xenomonitoring did detect a pre-patent infection prevalence of 10.8%, with Schistosoma bovis firmly incriminated. Molecular DNA characterisation of adult schistosomes (n = 19) by real-time polymerase chain reaction (PCR) and high-resolution melt profiling, alongside DNA sequencing, also identified S. bovis, although two worms were putative S. bovis-S. mattheei hybrids. Atypical intrauterine eggs of S. bovis were noted upon microscopy of a worm pair. A broader screen of 92 miracidia confirmed S. bovis and three miracidia as S. bovis-S. mattheei hybrids. Contrasting with Pemba Island, Zanzibar, where autochthonous transmission of S. bovis can occur, bovine schistosomiasis on Unguja Island currently appears restricted to imported animals alone. However, the seminal detection of putative S. bovis-mattheei hybrids, alongside the current inadequate quarantine facilities at Muwanda, raises a new concern that such hybrid schistosomes may escape and enter the island's hinterland. Should this happen, surveillance and control of urogenital schistosomiasis on Unguja would be compromised and further complicated. We therefore strongly recommend immediate repair and improved maintenance of governmental animal quarantine facilities. Future epidemiological surveys of imported cattle are now well justified, not only to better understand the full repertoire of hybrid schistosomes present but also to develop appropriate mitigating interventions.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"89"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883948/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567709","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":"Breed-dependent associations of production characteristics with on-farm seropositivity for Ostertagia ostertagi in dairy cows.","authors":"Lisa Kuehne, Martina Hoedemaker, Christina Strube, Gabriela Knubben-Schweizer, Andrea Springer, Andreas W Oehm","doi":"10.1186/s13071-025-06728-9","DOIUrl":"10.1186/s13071-025-06728-9","url":null,"abstract":"<p><strong>Background: </strong>Pasture-borne parasites like Ostertagia ostertagi have a negative effect on dairy cow health and productivity. The aim of the present study was to assess potential breed-dependent associations of O. ostertagi seropositivity with dairy cow production traits, i.e. milk yield, milk fat and milk protein.</p><p><strong>Methods: </strong>We describe these associations in German Holstein (GH) cows, a specialised dairy breed, compared with a dual-purpose breed, i.e. German Simmental (SIM). Data from 560 farms across Germany housing 93,030 dairy cows were included. Of the 560 farms, 383 farms housed GH cows and 177 housed SIM. Potential breed-dependent associations of O. ostertagi seropositivity with production characteristics were explored via a two-way interaction term using quantile regression. Pasture access, farming type (organic vs. conventional), herd size (number of cows) and study year were included as confounders. The relationship of O. ostertagi seropositivity with production traits based on breed was further examined via estimated marginal means.</p><p><strong>Results: </strong>Ostertagia ostertagi bulk tank milk (BTM) seropositivity was associated with lower median milk yield, milk fat and milk protein on GH farms, whereas no differences could be detected between seropositive and seronegative SIM farms. The difference in the production parameters per cow and year at GH farms associated with O. ostertagi seropositivity were 631.6 kg milk yield (P < 0.001), 20.0 kg milk fat (P < 0.001) and 17.0 kg milk protein (P = 0.01).</p><p><strong>Conclusions: </strong>This study indicated differential associations of O. ostertagi seropositivity and production level of cows depending on breed. Our results suggest that seropositivity is associated with lower milk yield, milk fat and milk protein in high-performance dairy breeds, whereas no such association may be present in dual-purpose breeds.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"91"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883928/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567728","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":"Risk assessment of an Aedes flavivirus and its effect on pathogenic flavivirus replication in mosquitoes.","authors":"Yumei Fu, Wan Zhao, Shaohui Wu, Jinqian Li, Qing Liu, Feng Jiang, Hong Lu, Le Kang, Qianfeng Xia, Feng Cui","doi":"10.1186/s13071-025-06711-4","DOIUrl":"10.1186/s13071-025-06711-4","url":null,"abstract":"<p><strong>Background: </strong>Mosquitoes are efficient vectors of medically significant flaviviruses and serve as hosts for insect-specific flaviviruses (ISFs). Aedes flavivirus (AEFV) is a classical ISF. Given the increasing discovery of ISFs, it is urgent to evaluate the potential risk of ISFs to human health as well as their impact on the transmission of pathogenic flaviviruses.</p><p><strong>Methods: </strong>We isolated a strain of AEFV from wild Aedes albopictus populations in Hainan Province, China, using iodixanol density-gradient ultracentrifugation. The infection of the AEFV Hainan strain in Aedes, Culex, and four mammalian cell lines was investigated using fluorescence in situ hybridization (FISH) assays, and relative and absolute quantitative polymerase chain reaction (qPCR). Whether AEFV alters the vector competence of Ae. albopictus for pathogenic arboviruses and the underlying immune mechanisms were explored.</p><p><strong>Results: </strong>The AEFV Hainan strain showed close genetic similarity to strains from Yunnan province of China, Thailand, and Peru. This strain was capable of infecting Ae. albopictus and Ae. aegypti but not Culex quinquefasciatus. Cell entry was the critical barrier for AEFV infection in Cx. quinquefasciatus cells. The infection risk of the AEFV Hainan strain in four mammalian cells (BHK-21, Vero, 293 T, and HeLa) was quite low due to the failure of cell entry or extremely limited replication. Prior infection of AEFV was detrimental to the replication of Zika virus and dengue virus serotype 2 in Ae. albopictus through activation of the Janus kinase/signal transducer and activator of transcription, Toll, or RNA interference pathway.</p><p><strong>Conclusions: </strong>Our work excludes the risk of the AEFV Hainan strain to human health and highlights its potential as an immune inducer to sabotage Aedes mosquito ability for viral transmission.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"88"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11881423/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567841","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":"Asian tiger mosquito in the oil-producing city of Soyo: the first report of Aedes (Stegomyia) albopictus (Skuse, 1894) in Angola.","authors":"José Franco Martins, Arlete Dina Troco, Cátia Marques, Vicente Chipepa, Gonçalo Seixas, João Pinto, Luzala Garcia, Cani Pedro Jorge, Eusébio Manuel, Gonçalo Alves","doi":"10.1186/s13071-025-06741-y","DOIUrl":"10.1186/s13071-025-06741-y","url":null,"abstract":"<p><strong>Background: </strong>The Asian tiger mosquito, Aedes albopictus (Skuse, 1894), is a highly invasive species that has successfully colonized many tropical and temperate regions worldwide. Its rapid global spread is strongly associated with human activities and has created favorable conditions for the emergence of human arboviruses in new geographic areas.</p><p><strong>Methods: </strong>Mosquito larvae were collected by community health workers from different breeding sites and reared to adults in a field insectary. Adult mosquitoes were morphologically identified to species level. Species identification was confirmed by cytochrome oxidase subunit I DNA barcoding.</p><p><strong>Results: </strong>We report the first detection of Aedes albopictus in Angola during an Anopheles stephensi survey conducted in Soyo, Zaire Province. Phylogenetic analysis indicated that the Angolan Ae. albopictus population clusters with sequences from Central African countries, suggesting an introduction from within the continent.</p><p><strong>Conclusions: </strong>The presence of Ae. albopictus in Angola highlights the need for enhanced vector surveillance and control measures to prevent the emergence of arboviral diseases. This finding emphasizes the relevance of collaboration between local health authorities, communities, and international organizations in monitoring the spread of invasive mosquito species.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"90"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11884181/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143567711","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}