Parasites & Vectors最新文献

{"title":"The spread of the invasive mosquito Aedes albopictus (Diptera: Culicidae) in Portugal: a first genetic analysis","authors":"Líbia Zé-Zé, Inês Campos Freitas, Manuel Silva, Patrícia Soares, Maria João Alves, Hugo Costa Osório","doi":"10.1186/s13071-024-06460-w","DOIUrl":"https://doi.org/10.1186/s13071-024-06460-w","url":null,"abstract":"Aedes albopictus, commonly known as the Asian tiger mosquito, has become one of the most invasive mosquito species. Over the last 5 decades, it has been introduced and established in various tropical and temperate regions worldwide. First reported in Europe in 1979 in Albania and later in Italy in 1990, the species is now established in 13 European Union (EU)/European Economic Area (EEA) countries and 337 regions (2023). In Portugal, Ae. albopictus was first detected in the Algarve and Penafiel regions in 2017, followed by Alentejo in 2022 and Lisbon in 2023. This mosquito species poses a significant public health risk as a vector for numerous pathogenic viruses, including dengue, Zika, and chikungunya. Aedes albopictus collected in Lisbon in 2023 were analyzed using cytochrome c oxidase I (COX) gene sequencing to understand their genetic relationships. Our data indicate that the Ae. albopictus mosquito populations detected in three locations in Lisbon in 2023 correspond to recent but distinct introduction events. Although there has been no local transmission of Aedes-transmitted viruses in mainland Portugal to date, the spread of the mosquito and increased international travel increase the risk of Aedes-borne disease outbreaks. The ongoing spread of Ae. albopictus in the country and the confirmed multiple introductions in new locations raise awareness of the need to monitor mosquito vectors to control and prevent autochthonous Aedes-borne disease outbreaks. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of multi-parallel quantitative real-time PCRs targeting different DNA regions and detecting soil-transmitted helminths in stool","authors":"Marina Papaiakovou, Rubén O. Cimino, Nils Pilotte, Julia Dunn, D. Timothy J. Littlewood, Steven A. Williams, Alejandro J. Krolewiecki, Rojelio Mejia","doi":"10.1186/s13071-024-06464-6","DOIUrl":"https://doi.org/10.1186/s13071-024-06464-6","url":null,"abstract":"Soil-transmitted helminths infect an estimated 18% of the world’s population, causing a significant health burden. Microscopy has been the primary tool for diagnosing eggs from fecal samples, but its sensitivity drops in low-prevalence settings. Quantitative real-time polymerase chain reaction (qPCR) is slowly increasing in research and clinical settings. However, there is still no consensus on preferred qPCR targets. We aimed to compare soil-transmitted helminth (STH) DNA detection methods by testing naïve stool samples spiked with known quantities of STH eggs and larvae. DNA extracts from spiked samples were tested using independent quantitative realtime PCR (qPCR) assays targeting ribosomal or putative non-protein coding satellite sequences. For Trichuris trichiura, there was a strong correlation between egg/larvae counts and qPCR results using either qPCR method (0.86 and 0.87, respectively). Strong correlations also existed for A. lumbricoides (0.60 and 0.63, respectively), but weaker correlations were found for Ancylostoma duodenale (0.41 for both assays) and Strongyloides stercoralis (0.48 and 0.65, respectively). No correlation for Necator americanus was observed when testing with either qPCR assay. Both assays had fair-to-moderate agreement across targets when using field-collected stool samples (0.28–0.45, for all STHs), except for S. stercoralis (0.12) with slight agreement. There is a strong correlation between qPCR results and egg/larvae counts. Our study confirms that qPCR is an effective diagnostic tool, even with low-intensity infections, regardless of the DNA-based diagnostic marker used. However, the moderate agreement between the two different qPCR assays when testing field samples highlights the need to understand the role of these targets in the genome so that the parasite burden can be quantified more accurately and consistently by qPCR. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Report of a new species of sand fly, Phlebotomus (Anaphlebotomus) ajithii n. sp. (Diptera: Psychodidae), from Western Ghats, India","authors":"Harish Kumar Shah, P. A. Fathima, Jose Jicksy, Prasanta Saini","doi":"10.1186/s13071-024-06468-2","DOIUrl":"https://doi.org/10.1186/s13071-024-06468-2","url":null,"abstract":"Western Ghats is a biodiversity treasure trove with reports of indigenous leishmaniasis cases. Hence, systematic sand fly surveillance was carried out among the tribal population. The present study reports a novel sand fly species, Phlebotomus (Anaphlebotomus) ajithii n. sp. (Diptera: Psychodidae), discovered in the Western Ghats of India. A comprehensive sand fly survey was conducted across the Kollam, Thrissur, Idukki, Kasaragod and Malappuram districts of Kerala, India. The survey spanned both indoor and outdoor habitats using standard collection methods over a 3-year, 3-month period. DNA barcoding of samples was performed targeting mitochondrial cytochrome c oxidase subunit I (COI) gene, and the sequence generated was subjected to phylogenetic analysis. Phlebotomus (Anaphlebotomus) ajithii, a new sand fly species, is recorded and described in this communication. The morphological relationship of the new species to other members of the subgenus Anaphlebotomus is discussed. Mitochondrial COI barcode followed by phylogenetic analysis confirmed that specimens of Ph. ajithii belong to the same taxonomic group, while a genetic distance of 11.7% from congeners established it as a distinct species. The Western Ghats, known for its rich biodiversity, has lacked systematic entomological surveys focusing on sand flies. This study aims to fill this gap and reports and describes a new species of sand fly. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights from multigene analysis: first report of a Southeast Asian Mosquito, Aedes (Mucidus) laniger (Diptera: Culicidae) on Jeju Island from Korea","authors":"Woo Jun Bang, Ara Seol, Seunggwan Shin","doi":"10.1186/s13071-024-06373-8","DOIUrl":"https://doi.org/10.1186/s13071-024-06373-8","url":null,"abstract":"Certain mosquitoes are known as dominant vectors worldwide, and transmit infectious diseases. The expansion of mosquito habitats due to climate change and increased human activities poses a significant health threat by facilitating the spread of various non-native infectious diseases. This study focused on the detection of the Southeast Asian mosquito species, Aedes (Mucidus) laniger (Wiedemann, 1820) on Jeju Island, the southernmost region of the Republic of Korea (ROK), highlighting the potential risks associated with the spread of vector-borne diseases, particularly emphasizing the elevated likelihood of invasion by Southeast Asian mosquitoes. Field surveys were conducted in August 2023 on Jeju Island. Adult mosquitoes were collected using BG-sentinel traps and identified to the species level using taxonomic keys. Morphological and molecular analyses were employed to confirm species designations. Molecular data, including mitochondrial and nuclear genes, were used for phylogenetic analysis, which was performed to compare and identify among recorded subgenera in ROK. Species distribution modeling for Ae. laniger was performed to predict potential habitats using R package ‘BIOMOD2’. The two specimens of Ae. laniger were collected for the first time on Jeju Island. Morphological and molecular analyses confirmed the identity of this species within the subgenus Mucidus and validated the first record of this species in the ROK. We employed a simple multigene phylogenetic analysis to confirm a new mosquito record at the genus and subgenus levels, finally validating the consistency between morphological identification and molecular phylogenetic outcomes. Furthermore, we have updated the taxonomic keys for the genus Aedes in the ROK, and revised mosquito lists for Jeju Island, incorporating the inclusion of Ae. laniger. On the basis of species distribution modeling, the area of suitable habitat for Ae. laniger is expected to expand due to climate change, but this change did not appear to be meaningful in East Asia. This case offers the first report of the Southeast Asian mosquito, Ae. laniger, in the ROK. The detection of this species on Jeju Island suggests the potential establishment of a breeding population their habitat and raises concerns about further expansion into the Korean Peninsula. Considering the annual occurrence of mosquito-borne disease cases in the Southeast Asia, it is essential to conduct monitoring not only in Jeju Island, where Ae. laniger has been identified, but also across the entire Korean Peninsula. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Baseline gut microbiota diversity and composition and albendazole efficacy in hookworm-infected individuals","authors":"Javier Gandasegui, Pedro E. Fleitas, Paula Petrone, Berta Grau-Pujol, Valdemiro Novela, Elisa Rubio, Osvaldo Muchisse, Anélsio Cossa, José Carlos Jamine, Charfudin Sacoor, Eric A. T. Brienen, Lisette van Lieshout, José Muñoz, Climent Casals-Pascual","doi":"10.1186/s13071-024-06469-1","DOIUrl":"https://doi.org/10.1186/s13071-024-06469-1","url":null,"abstract":"Soil-transmitted helminth (STH) infections account for a significant global health burden, necessitating mass drug administration with benzimidazole-class anthelmintics, such as albendazole (ALB), for morbidity control. However, ALB efficacy shows substantial variability, presenting challenges for achieving consistent treatment outcomes. We have explored the potential impact of the baseline gut microbiota on ALB efficacy in hookworm-infected individuals through microbiota profiling and machine learning (ML) techniques. Our investigation included 89 stool samples collected from hookworm-infected individuals that were analyzed by microscopy and quantitative PCR (qPCR). Of these, 44 were negative by microscopy for STH infection using the Kato-Katz method and qPCR 21 days after treatment, which entails a cure rate of 49.4%. Microbiota characterization was based on amplicon sequencing of the V3–V4 16S ribosomal RNA gene region. Alpha and beta diversity analyses revealed no significant differences between participants who were cured and those who were not cured, suggesting that baseline microbiota diversity does not influence ALB treatment outcomes. Furthermore, differential abundance analysis at the phylum, family and genus levels yielded no statistically significant associations between bacterial communities and ALB efficacy. Utilizing supervised ML models failed to predict treatment response accurately. Our investigation did not provide conclusive insights into the relationship between gut microbiota and ALB efficacy. However, the results highlight the need for future research to incorporate longitudinal studies that monitor changes in the gut microbiota related to the infection and the cure with ALB, as well as functional metagenomics to better understand the interaction of the microbiome with the drug, and its role, if there is any, in modulating anthelmintic treatment outcomes in STH infections. Interdisciplinary approaches integrating microbiology, pharmacology, genetics and data science will be pivotal in advancing our understanding of STH infections and optimizing treatment strategies globally. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study on the diversity of phlebotomine sand flies (Diptera, Psychodidae) in karstic limestone areas in Vientiane Province, Laos, with a description of two new species of Sergentomyia França and & Parrot","authors":"Khamsing Vongphayloth, Fano José Randrianambinintsoa, Khaithong Lakeomany, Nothasine Phommavanh, Tavun Pongsanarm, Veaky Vungkyly, Phonesavanh Luangamath, Somsanith Chonephetsarath, Paul T. Brey, Jérôme Depaquit","doi":"10.1186/s13071-024-06444-w","DOIUrl":"https://doi.org/10.1186/s13071-024-06444-w","url":null,"abstract":"Southeast Asia is well known as a hotspot of biodiversity. However, very little is known about cave-dwelling hematophagous insects that are medically important. Taxonomic knowledge and ecology of phlebotomine sand flies are very poorly studied in Laos, as well as in other countries in the region. Herein, we report species diversity data and some notes on the ecology of the detected species from these karstic limestone areas of Laos. Phlebotomine sand flies were collected using Centers for Disease Control and Prevention (CDC) light traps from limestone cave locations in three districts of Vientiane Province, Laos. Both morphological and molecular techniques were used for sand fly identification. Species diversity and abundance were analyzed according to sites, locations, collection seasons, and trapping positions. A total of 6564 sand flies, of which 5038 were females and 1526 were males, were morphologically identified into 20 species belonging to five genera (Chinius, Idiophlebotomus, Phlebotomus, Sergentomyia, and Grassomyia). The most abundant species were Chinius eunicegalatiae, Phlebotomus stantoni, Sergentomyia hivernus, Se. siamensis, and Idiophlebotomus longiforceps. Cytochrome b analysis results supported the morphological identification and revealed that Se. siamensis was separated from other members of the Se. barraudi group. Two new species, Se. dvoraki n. sp. and Se. marolii n. sp., were described. Sand fly density was generally high except in a cave in Vangvieng, with species richness ranging from 14 to 18 across different caves. Outside caves had higher species richness (R = 20) and diversity (H = 2.50) than cave entrances (R = 18, H = 2.41) and interiors (R = 16, H = 2.13). Seasonal variations showed high sand fly density in Feung and Hinheup during both dry and rainy seasons, while Vangvieng had a notable decrease in density during the dry season (D = 6.29). This study revealed that the diversity of phlebotomine sand fly fauna in Laos, particularly in karstic limestone areas, is greater than previously known. However, the taxonomic status of many species in Laos, as well as Southeast Asia, still needs more in-depth study using both morphological characters and molecular methods. Many species could be found from inside, at the entrance, and outside of caves, indicating a wide range of host-seeking behavior or possible natural breeding in the karstic cave areas. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-time PCR for malaria diagnosis and identification of Plasmodium species in febrile patients in Cubal, Angola","authors":"Alejandro Mediavilla, Aroa Silgado, Begoña Febrer-Sendra, Beatriz Crego-Vicente, Patricia Martínez-Vallejo, Carles Rubio Maturana, Lidia Goterris, Arlette Nindia, Joan Martínez-Campreciós, Sandra Aixut, María Luisa Aznar-Ruiz-de-Alegría, Pedro Fernández-Soto, Antonio Muro, Fernando Salvador, Israel Molina, Pedro Berzosa, Inés Oliveira-Souto, Elena Sulleiro","doi":"10.1186/s13071-024-06467-3","DOIUrl":"https://doi.org/10.1186/s13071-024-06467-3","url":null,"abstract":"Malaria is the parasitic disease with the highest morbimortality worldwide. The World Health Organization (WHO) estimates that there were approximately 249 million cases in 2022, of which 3.4% were in Angola. Diagnosis is based on parasite identification by microscopy examination, antigen detection, and/or molecular tests, such as polymerase chain reaction (PCR). This study aimed to evaluate the usefulness of real-time PCR as a diagnostic method for malaria in an endemic area (Cubal, Angola). A cross-sectional study was carried out at the Hospital Nossa Senhora da Paz in Cubal, Angola, including 200 patients who consulted for febrile syndrome between May and July 2022. From each patient, a capillary blood sample was obtained by finger prick for malaria field diagnosis [microscopy and rapid diagnostic test (RDT)] and venous blood sample for real-time PCR performed at the Hospital Universitario Vall d’Hebron in Barcelona, Spain. Any participant with a positive result from at least one of these three methods was diagnosed with malaria. Of the 200 participants included, 54% were female and the median age was 7 years. Malaria was diagnosed by at least one of the three techniques (microscopy, RDT, and/or real-time PCR) in 58% of the participants, with RDT having the highest percentage of positivity (49%), followed by real-time PCR (39.5%) and microscopy (33.5%). Of the 61 discordant samples, 4 were only positive by microscopy, 13 by real-time PCR, and 26 by RDT. Plasmodium falciparum was the most frequent species detected (90.63%), followed by P. malariae (17.19%) and P. ovale (9.38%). Coinfections were detected in ten participants (15.63%): six (60%) were caused by P. falciparum and P. malariae, three (30%) by P. falciparum and P. ovale, and one (10%) triple infection with these three species. In addition, it was observed that P. falciparum and P. malariae coinfection significantly increased the parasite density of the latter. RDT was the technique with the highest positivity rate, followed by real-time PCR and microscopy. The results of the real-time PCR may have been underestimated due to suboptimal storage conditions during the transportation of the DNA eluates. However, real-time PCR techniques have an important role in the surveillance of circulating Plasmodium species, given the epidemiological importance of the increase in non-falciparum species in the country, and can provide an estimate of the intensity of infection. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mosquito dynamics and their drivers in peri-urban Antananarivo, Madagascar: insights from a longitudinal multi-host single-site survey","authors":"Michaël Luciano Tantely, Hélène Guis, Manou Rominah Raharinirina, Maminirina Fidelis Ambinintsoa, Iavonirina Randriananjantenaina, Haja Johnson Velonirina, Christophe Revillion, Vincent Herbreteau, Annelise Tran, Romain Girod","doi":"10.1186/s13071-024-06393-4","DOIUrl":"https://doi.org/10.1186/s13071-024-06393-4","url":null,"abstract":"Antananarivo, the capital city of Madagascar, is experiencing a steady increase in population growth. Due to the abundance of mosquito vectors in this locality, the population exposed to mosquito-borne diseases is therefore also increasing, as is the risk of epidemic episodes. The aim of the present study was to assess, in a resource-limited setting, the information on mosquito population dynamics and disease transmission risk that can be provided through a longitudinal entomological study carried out in a multi-host single site. Mosquitoes were collected every 15 days over 16 months (from January 2017 to April 2018) using six CDC-light traps in a peri-urban area of Antananarivo. Multivariable generalised linear models were developed using indoor and outdoor densities of the predominant mosquito species as response variables and moon illumination, environmental data and climatic data as the explanatory variables. Overall, 46,737 mosquitoes belonging to at least 20 species were collected, of which Culex antennatus (68.9%), Culex quinquefasciatus (19.8%), Culex poicilipes (3.7%) and Anopheles gambiae sensu lato (2.3%) were the most abundant species. Mosquito densities were observed to be driven by moon illumination and climatic factors interacting at different lag periods. The outdoor models demonstrated biweekly and seasonal patterns of mosquito densities, while the indoor models demonstrated only a seasonal pattern. An important diversity of mosquitoes exists in the peri-urban area of Antananarivo. Some well-known vector species, such as Cx. antennatus, a major vector of West Nile virus (WNV) and Rift-Valley fever virus (RVFV), Cx. quinquefasciatus, a major vector of WNV, Cx. poicilipes, a candidate vector of RVFV and An. gambiae sensu lato, a major vector of Plasmodium spp., are abundant. Importantly, these four mosquito species are present all year round, even though their abundance declines during the cold dry season, with the exception of Cx. quinquefasciatus. The main drivers of their abundance were found to be temperature, relative humidity and precipitation, as well as—for outdoor abundance only—moon illumination. Identifying these drivers is a first step towards the development of pathogen transmission models (R0 models), which are key to inform public health stakeholders on the periods of most risk for vector-borne diseases. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular xenomonitoring as an indicator of microfilaraemia prevalence for lymphatic filariasis in Samoa in 2019","authors":"Maddison Howlett, Helen J. Mayfield, Brady McPherson, Lisa Rigby, Robert Thomsen, Steven A. Williams, Nils Pilotte, Shannon M. Hedtke, Patricia M. Graves, Therese Kearns, Take Naseri, Sarah Sheridan, Angus McLure, Colleen L. Lau","doi":"10.1186/s13071-024-06463-7","DOIUrl":"https://doi.org/10.1186/s13071-024-06463-7","url":null,"abstract":"Lymphatic filariasis (LF) is a globally significant, vector-borne, neglected tropical disease that can result in severe morbidity and disability. As the World Health Organization (WHO) Global Programme to Eliminate Lymphatic Filariasis makes progress towards LF elimination, there is greater need to develop sensitive strategies for post-intervention surveillance. Molecular xenomonitoring (MX), the detection of pathogen DNA in vectors, may provide a sensitive complement to traditional human-based surveillance techniques, including detection of circulating filarial antigen and microfilaraemia (Mf). This study aims to explore the relationship between human Mf prevalence and the prevalence of polymerase chain reaction (PCR)-positive mosquitoes using MX. This study compared Mf and MX results from a 2019 community-based survey conducted in 35 primary sampling units (PSUs) in Samoa. This study also investigated concordance between presence and absence of PCR-positive mosquitoes and Mf-positive participants at the PSU level, and calculated sensitivity and negative predictive values for each indicator using presence of any Mf-positive infection in humans or PCR-positive mosquitoes as a reference. Correlation between prevalence of filarial DNA in mosquitoes and Mf in humans was estimated at the PSU and household/trap level using mixed-effect Bayesian multilevel regression analysis. Mf-positive individuals were identified in less than half of PSUs in which PCR-positive mosquito pools were present (13 of 28 PSUs). Prevalence of PCR-positive mosquitoes (each species separately) was positively correlated with Mf prevalence in humans at the PSU level. Analysed at the species level, only Aedes polynesiensis demonstrated strong evidence of positive correlation (r) with human Mf prevalence at both PSU (r: 0.5, 95% CrI 0.1–0.8) and trap/household levels (r: 0.6, 95% CrI 0.2–0.9). Findings from this study demonstrate that MX can be a sensitive surveillance method for identifying residual infection in low Mf prevalence settings. MX identified more locations with signals of transmission than Mf-testing. Strong correlation between estimated PCR-positive mosquitoes in the primary vector species and Mf in humans at small spatial scales demonstrates the utility of MX as an indicator for LF prevalence in Samoa and similar settings. Further investigation is needed to develop MX guidelines to strengthen the ability of MX to inform operational decisions. ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142202723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trypanosoma cruzi reprograms mitochondrial metabolism within the anterior midgut of its vector Rhodnius prolixus during the early stages of infection.","authors":"Radouane Ouali, Larissa Rezende Vieira, Didier Salmon, Sabrina Bousbata","doi":"10.1186/s13071-024-06415-1","DOIUrl":"10.1186/s13071-024-06415-1","url":null,"abstract":"<p><strong>Background: </strong>Trypanosoma cruzi is transmitted to humans by hematophagous bugs belonging to the Triatominae subfamily. Its intra-vectorial cycle is complex and occurs exclusively in the insect's midgut. Dissecting the elements involved in the cross-talk between the parasite and its vector within the digestive tract should provide novel targets for interrupting the parasitic life cycle and affecting vectorial competence. These interactions are shaped by the strategies that parasites use to infect and exploit their hosts, and the host's responses that are designed to detect and eliminate parasites. The objective of the current study is to characterize the impact of T. cruzi establishment within its vector on the dynamics of its midgut.</p><p><strong>Methods: </strong>In this study, we evaluated the impact of T. cruzi infection on protein expression within the anterior midgut of the model insect Rhodnius prolixus at 6 and 24 h post-infection (hpi) using high-throughput quantitative proteomics.</p><p><strong>Results: </strong>Shortly after its ingestion, the parasite modulates the proteome of the digestive epithelium by upregulating 218 proteins and negatively affecting the expression of 11 proteins involved in a wide array of cellular functions, many of which are pivotal due to their instrumental roles in cellular metabolism and homeostasis. This swift response underscores the intricate manipulation of the vector's cellular machinery by the parasite. Moreover, a more in-depth analysis of proteins immediately induced by the parasite reveals a pronounced predominance of mitochondrial proteins, thereby altering the sub-proteomic landscape of this organelle. This includes various complexes of the respiratory chain involved in ATP generation. In addition to mitochondrial metabolic dysregulation, a significant number of detoxifying proteins, such as antioxidant enzymes and P450 cytochromes, were immediately induced by the parasite, highlighting a stress response.</p><p><strong>Conclusions: </strong>This study is the first to illustrate the response of the digestive epithelium upon contact with T. cruzi, as well as the alteration of mitochondrial sub-proteome by the parasite. This manipulation of the vector's physiology is attributable to the cascade activation of a signaling pathway by the parasite. Understanding the elements of this response, as well as its triggers, could be the foundation for innovative strategies to control the transmission of American trypanosomiasis, such as the development of targeted interventions aimed at disrupting parasite proliferation and transmission within the triatomine vector.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380418/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142146026","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}