Parasites & Vectors最新文献

{"title":"Potential associations between Schistosoma mansoni infection and physico-chemical characteristics and water-related human activities in Côte d'Ivoire: a cross-sectional study.","authors":"Jean-Baptiste K Sékré, Nana R Diakité, Rufin K Assaré, Jules N Kouadio, Gaoussou Coulibaly, Cyrille K Konan, Alain-Claver Kouamin, Aboulaye Méité, Jan Hattendorf, Mamadou Ouattara, Jürg Utzinger, Eliézer K N'Goran","doi":"10.1186/s13071-024-06466-4","DOIUrl":"10.1186/s13071-024-06466-4","url":null,"abstract":"<p><strong>Background: </strong>Schistosomiasis remains a public health problem, particularly in sub-Saharan Africa. The disease is intimately connected to poverty and environmental factors. Our research was readily embedded into a multi-country schistosomiasis oversampling study. The aim of the study presented here was to determine the prevalence of Schistosoma mansoni and to investigate the role of water body characteristics and water-related human activities in disease transmission.</p><p><strong>Methods: </strong>In August and September 2022, a cross-sectional study was conducted in the western part of Côte d'Ivoire. Stool and urine samples were collected from 1602 and 1729 children aged 5-14 years, respectively, in 65 villages in the health districts of Biankouma, Ouaninou and Touba. Additionally, data were collected from direct observation of water-related activities at water bodies and interviews conducted with community leaders and health workers. The prevalence and risk factors for Schistosoma infection were assessed using generalised estimating equation models.</p><p><strong>Results: </strong>The prevalence ofS. mansoni and S. haematobium were 27.4% (95% confidence interval [CI] 21.5-34.3%) and 0.1% (95% CI 0.03-0.5%), respectively. Low prevalence of soil-transmitted helminths was observed with 2.4%, 0.4% and 0.2% for hookworm, Trichuris trichiura and Ascaris lumbricoides, respectively. At the health district level, we found S. mansoni prevalence of 34.4% (95% CI 25.0-45.3%), 34.3% (95% CI 24.0-46.2%) and 16.3% (95% CI 9.5-26.6%) for Biankouma, Ouaninou and Touba, respectively. Female and male participants were at a similar risk of infection (29.0% vs. 26.0%, odds ratio [OR]: 1.18, 95% CI 0.92-1.50). Children aged 9-14 years showed a higher prevalence than their younger counterparts aged 5-8 years (34.5% vs. 22.7%, OR: 1.80, 95% CI 1.42-2.27). High infection prevalence was observed in villages where children were washing clothes and dishes at open surface water sites and pursued recreational activities (e.g. swimming and playing in the water). The temperature, total dissolved solids and pH of water samples showed no significant association with S. mansoni infection at the village unit.</p><p><strong>Conclusions: </strong>Human water-related activities such as washing clothes and playing in the water are risk factors for S. mansoni transmission. Hence, preventive chemotherapy should be combined with information, education and communication to avoid or reduce the frequency of water exposure in children as part of a comprehensive package of interventions towards elimination of schistosomiasis as a public health problem.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"422"},"PeriodicalIF":3.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11462818/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142392252","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 attrition, physical and insecticidal durability of two dual active ingredient nets (Interceptor® G2 and Royal Guard®) in Benin, West Africa: results from a durability study embedded in a cluster randomised controlled trial.","authors":"Corine Ngufor, Josias Fagbohoun, Augustin Fongnikin, Juniace Ahoga, Thomas Syme, Idelphonse Ahogni, Manfred Accrombessi, Natacha Protopopoff, Jackie Cook, Edouard Dangbenon, Arthur Sovi, Marie Baes, Olivier Pigeon, Damien Todjinou, Renaud Govoetchan, Germain Gil Padonou, Martin Akogbeto","doi":"10.1186/s13071-024-06504-1","DOIUrl":"10.1186/s13071-024-06504-1","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Studies evaluating the attrition, physical and insecticidal durability of dual active ingredient (AI) insecticide-treated nets (ITNs) are essential for making programmatic decisions regarding their deployment. We performed a prospective study embedded in a cluster randomised controlled trial (cRCT) to evaluate the attrition, fabric integrity and insecticidal durability of Interceptor® G2 (alpha-cypermethrin-chlorfenapyr) and Royal Guard® (alpha-cypermethrin-pyriproxyfen), compared to Interceptor® (alpha-cypermethrin) in Benin.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;A total of 2428 study nets in 1093 randomly selected households in five clusters per arm of the cRCT were monitored for ITN attrition and fabric integrity every 6-12 months post-distribution. Householders were further surveyed to investigate non-study net use and their preference for ITN fabric types used in the study nets. A second cohort of 120 nets per ITN type were withdrawn every 12 months and assessed for chemical content and insecticidal activity in laboratory bioassays. Alpha-cypermethrin bioefficacy was investigated using the susceptible Anopheles gambiae Kisumu strain, and chlorfenapyr and pyriproxyfen bioefficacy were investigated using the pyrethroid-resistant Anopheles coluzzii Akron strain. Net pieces were tested in WHO cone bioassays and tunnel tests for alpha-cypermethrin and in tunnel tests for chlorfenapyr; pyriproxyfen activity was assessed in cone bioassays as the reduction in fertility of blood-fed survivors using ovary dissection. Bioefficacy was expressed as the proportion of ITNs passing predetermined WHO criteria, namely knock-down ≥ 95% or 24/72 h mortality ≥ 80% or reduction in fertility ≥ 50%.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Overall ITN survivorship was 52% at 24 months and fell to 15% at 36 months. Median ITN survival time was lower with Royal Guard® relative to Interceptor® [1.6 vs 2.3 years; hazard ratio (HR) 1.49, 95% confidence interval (CI) 1.36-1.66; p &lt; 0.001] and Interceptor® G2 (1.6 vs 2.1 years; HR 1.33, 95% CI 1.20-1.47; p &lt; 0.001). Householders overwhelmingly preferred polyester nets over polyethylene nets (96%), and more Royal Guard® nets were replaced with spare polyester nets from previous campaigns. All Royal Guard® nets passed efficacy criteria for alpha-cypermethrin at all time points (100%) while ITN pass rates after 24 months had fallen to &lt; 40% for pyriproxyfen and chlorfenapyr. The chemical content analysis showed a higher loss rate of the non-pyrethroid insecticides relative to the pyrethroids in each dual ingredient AI ITN; 74% vs 47% for Royal Guard® and 85% vs 63% for Interceptor® G2 at 36 months.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;The median ITN survival time for Interceptor® G2 (2.1 years) and Royal Guard® (1.6 years) in Benin is substantially lower than 3 years. Royal Guard® nets were discarded more quickly by householders, partly due to their low preference for polyethylene nets. The insecticidal activ","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"420"},"PeriodicalIF":3.0,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11459981/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142392264","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":"Exploring transmission dynamics of the Sarcoptes scabiei mite in humans by combining molecular typing and epidemiological variables, the Netherlands 2016-2023.","authors":"Martijn Vink, Hester Coppoolse, Anneke Bergmans, Meike Wennekes, Suzan Pas, Jane Pattipeilohy-van Ommen, Marieta Braks, Sylvia Bruisten, Annemie Galimont-Collen, Bas Wintermans, Ewout Fanoy","doi":"10.1186/s13071-024-06488-y","DOIUrl":"https://doi.org/10.1186/s13071-024-06488-y","url":null,"abstract":"<p><strong>Background: </strong>Scabies, an infestation of the mite Sarcoptes scabiei, has seen an increase in clinical diagnoses in the Netherlands since 2011. This study aimed to analyse PCR-positive S. scabiei skin samples through partial genome sequencing and to link findings to patient epidemiological characteristics.</p><p><strong>Methods: </strong>Skin samples were collected from individuals in the Netherlands between January 2016 and January 2023. On the PCR-positive S. scabiei skin samples, partial mitochondrial cytochrome c oxidase subunit 1 gene (cox1) sequencing was performed to assess genetic variability. Epidemiological information was collected through interviews. We examined associations between cox1 subtypes, epidemiological factors and treatment outcomes.</p><p><strong>Results: </strong>Sequencing results were obtained from 128 patients, with epidemiological information available for 55 (43%) of these patients. Fifteen distinct cox1 subtypes were identified. Subtype 01 was most prevalent (45%) and present across all age groups and social settings. The remaining subtypes were less common and not consistently found in all contexts. Five clusters were identified, each with identical cox1 subtypes. Comparative analysis with GenBank sequences revealed genetic similarities with strains from Australia, the USA and China, suggesting the global distribution and transmission of specific subtypes. A substantial proportion (73%) of patients with scabies required multiple treatments to eradicate the infestation, with no subtype-related differences.</p><p><strong>Conclusions: </strong>This is the first study linking S. scabiei sequencing results to patient epidemiological data. Several subtypes clustered in specific geographic regions and social contexts, underscoring localised transmission patterns. Further research with larger sample sizes is needed to enhance our understanding of the transmission of this mite. This study provides valuable insights that will strengthen scabies control efforts.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"419"},"PeriodicalIF":3.0,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11459799/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142392250","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":"Neurobartonelloses: emerging from obscurity!","authors":"Janice C Bush, Cynthia Robveille, Ricardo G Maggi, Edward B Breitschwerdt","doi":"10.1186/s13071-024-06491-3","DOIUrl":"10.1186/s13071-024-06491-3","url":null,"abstract":"<p><strong>Background: </strong>Bartonella species are fastidious, intracellular bacteria responsible for an expanding array of human pathologies. Most are considered to be transmitted by direct inoculation with infected bodily fluids from a mammalian reservoir species or vector-transmitted through a variety of arthropod species and their excrement. However, there are mounting reports of infection in the absence of documented animal or vector contact. A variety of Bartonella species have been documented in conditions affecting both the peripheral and central nervous systems. More common conditions, including neuroretinitis, are often associated with Bartonella henselae. However, Bartonella quintana, the agent of trench fever, as well as emerging pathogens related to rodent reservoir species, B. grahamii and B. elizabethae, have also been documented. Encephalitis and encephalopathy, also most often associated with B. henselae, have been reported with B. quintana, B. washoensis (ground squirrels) and B. vinsonii subsp. vinsonii (voles) infections. Bartonella infections have also been associated with peripheral neuropathies, such as cranial nerve paresis and neuropathic pain, including infection with less commonly encountered species such as Bartonella koehlerae. Recently, molecular diagnostic testing revealed that DNA from Bartonella spp. was found to be more prevalent in blood of patients with neuropsychiatric disorders such as schizophrenia and psychoses compared to healthy controls.</p><p><strong>Methods: </strong>A systematic literature search was conducted on PubMed, Google Scholar and Web of Science. Search terms included Bartonella and specific neurological conditions and focused on peer-reviewed case reports published after 2012 pursuant to a prior review, with limited exceptions for conditions not previously covered. Published diagnostic testing, serology, molecular testing or pathology, were necessary for inclusion, except for one case which had clinical and epidemiological evidence consistent with diagnosis along with follow-up.</p><p><strong>Results: </strong>Neurobartonelloses included neuralgic amyotrophy, complex regional pain syndrome, chronic inflammatory demyelinating polyneuropathy, cranial nerve paralysis, Guillain-Barré syndrome, peripheral vasculitic polyneuropathy, acute transverse myelopathy, neuroretinitis, encephalitis/encephalopathy, cerebral vasculitis/aneurysm and neuropsychiatric conditions.</p><p><strong>Conclusions: </strong>The breadth of reported symptoms and clinical syndromes associated with an increasing number of Bartonella species continues to expand. Increased clinical awareness of this important zoonotic pathogen is necessary to advance One Health among the medical and veterinary communities.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"416"},"PeriodicalIF":3.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11452993/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142378070","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":"Differences in seasonal dynamics and pyrethroid resistance development among Anopheles Hyrcanus group species.","authors":"Do Eun Lee, Jeong Heum Han, Gang Chan Lee, Junhyeong Choi, Wonyong Kwun, Si Hyeock Lee, Ju Hyeon Kim","doi":"10.1186/s13071-024-06462-8","DOIUrl":"10.1186/s13071-024-06462-8","url":null,"abstract":"<p><strong>Background: </strong>The Anopheles Hyrcanus group, which transmits Plasmodium vivax, consists of six confirmed species in South Korea. An epidemiological study revealed differences in the seasonal occurrence patterns of each species. Pyrethroid resistance in An. sinensis dates back to the early 2000s, whereas information on pyrethroid resistance in other species is lacking despite their greater significance in malaria epidemiology.</p><p><strong>Methods: </strong>Anopheles mosquitoes were collected from two malaria-endemic regions in South Korea for 2 years and their knockdown resistance (kdr) mutations were genotyped. The larval susceptibility to λ-cyhalothrin was compared in six Anopheles species and its seasonal changes in three species were investigated. The full-length sequences of the voltage-sensitive sodium channel (VSSC) were compared across six species to evaluate potential target-site insensitivity. The contribution of the kdr mutation to phenotypic resistance was confirmed by comparing median lethal time (LT₅₀) to λ-cyhalothrin between populations of Anopheles belenrae with distinct genotypes.</p><p><strong>Results: </strong>The composition and seasonal occurrence of rare species (Anopheles kleini, Anopheles lestri, and Anopheles sineroides) varied considerably, whereas An. sinensis occurs continuously throughout the season. A kdr mutation in the form of heterozygous allele was newly identified in An. belenrae, An. lesteri, An. pullus, and An. sineroides. The baseline susceptibility to λ-cyhalothrin was the highest in An. belenrae, followed by An. lesteri, An. sineroides, An. kleini, An. pullus, and An. sinensis, with median lethal concentration (LC₅₀) values ranging from 6.0- to 73.5-fold higher than that of An. belenrae. The susceptibility of An. sinensis and An. pullus varied by season, whereas that of An. belenrae remained stable. The kdr-heterozygous An. belenare population exhibited 5.1 times higher LT₅₀ than that of the susceptible population. Species-specific VSSC sequence differences were observed among the six species.</p><p><strong>Conclusions: </strong>Our findings suggest that the status and extent of pyrethroid resistance vary among Anopheles Hyrcanus group species. While An. sinensis, the predominant species, developed a considerable level of pyrethroid resistance through kdr mutation, the resistance levels of other species appeared to be less pronounced. Large-scale monitoring is crucial to fully understand species-specific seasonal occurrence and resistance status for effective management strategies, considering the ongoing impact of climate change on their vectorial capacity.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"417"},"PeriodicalIF":3.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11456232/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142378068","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":"Evaluating the effects of short-term low temperature on the growth and development of Trichopria drosophilae based on the age-stage two-sex life table.","authors":"Qiang Chen, Jinlong Zhang, Ye Tian, Juan Li, Weizhi Ning, Guohua Chen, Xiaoming Zhang","doi":"10.1186/s13071-024-06480-6","DOIUrl":"10.1186/s13071-024-06480-6","url":null,"abstract":"<p><strong>Background: </strong>The effects of low temperatures on parasitic wasps are crucial for maintaining farmland biodiversity and enhancing biological control, especially given the implications of global warming and frequent extreme cold events.</p><p><strong>Methods: </strong>We studied the effects of different low temperatures (-8 ± 1 °C, -4 ± 1 °C, 0 ± 1 °C, 4 ± 1 °C, and 8 ± 1 °C) on the mating frequency and duration of male adults of Trichopria drosophilae and the number of pupae beaten by female adults, and constructed the age-stage two-sex life table of T. drosophilae.</p><p><strong>Results: </strong>This study found that male T. drosophilae adults exposed to low temperatures for 12 h significantly altered their mating behavior, peaking between 15:00 and 17:00. As the temperature dropped during the exposure, both the mating frequency of T. drosophilae and the duration of pupal beating were affected. The survival rate of female adults dropped from 39.55% at 8 °C to just 21.17% at -8 °C. Low-temperature treatment shortened the development period and lifespan for T. drosophilae adults. They developed 4.71 days faster and had a total lifespan that was 10.66 days shorter than those in the control group after being exposed to -8 °C. Furthermore, the average number of eggs laid by females at -8 °C was 4.46 less than that at 8 °C and 6.16 less than that in the control group, which laid an average of 21.55 eggs. The net reproductive rate (R₀) of T. drosophilae decreased with lower temperatures, reaching a low of 23.64 at -8 °C. Conversely, the intrinsic growth rate (r_m) actually increased as temperatures dropped, with the lowest value being 0.21 at -8 °C.</p><p><strong>Conclusions: </strong>The findings indicate that short-term exposure to low temperatures hampers the growth and population increase of T. drosophilae, thereby reducing their effectiveness as biological control agents.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"418"},"PeriodicalIF":3.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11456240/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142378069","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":"Dihydroartemisinin suppresses the susceptibility of Anopheles stephensi to Plasmodium yoelii by activating the Toll signaling pathway.","authors":"Tingting Liu, Dan Zheng, Jing Wang, Xin Li, Shasha Yu, Zhilong Liu, Feifei Zheng, Caizhi Zhao, Xuesen Yang, Ying Wang","doi":"10.1186/s13071-024-06497-x","DOIUrl":"10.1186/s13071-024-06497-x","url":null,"abstract":"<p><strong>Background: </strong>Malaria is a serious public health concern. Artemisinin and its derivatives are first-line drugs for the treatment of Plasmodium falciparum malaria. In mammals, artemisinin exhibits potent anti-inflammatory and immunoregulatory properties. However, it is unclear whether artemisinin plays a regulatory role in the innate immunity of mosquitoes, thereby affecting the development of Plasmodium in Anopheles when artemisinin and its metabolites enter mosquitoes. This study aims to determine the effect of dihydroartemisinin (DHA), a first-generation semisynthetic derivative of artemisinin, on innate immunity and malaria vector competence of Anopheles stephensi.</p><p><strong>Methods: </strong>Anopheles stephensi was fed Plasmodium-infected mice treated with DHA via gavage, Plasmodium-infected blood containing DHA in vitro, or DHA-containing sugar, followed by Plasmodium yoelii infection. The engorged female mosquitoes were separated and dissected 8 and 17 days after infection. Plasmodium oocysts and sporozoites were counted and compared between the control and DHA-treated groups. Additionally, total RNA and proteins were extracted from engorged mosquitoes 24 and 72 h post infection (hpi). Real-time polymerase chain reaction (PCR) and western blotting were performed to detect the transcriptional levels and protein expression of immune molecules in mosquitoes. Finally, the Toll signaling pathway was inhibited via RNA interference and the infection density was analyzed to confirm the role of the Toll signaling pathway in the effect of DHA on the vector competence of mosquitoes.</p><p><strong>Results: </strong>DHA treatment via different approaches significantly reduced the number of Plasmodium oocysts and sporozoites in mosquitoes. The transcriptional levels of anti-Plasmodium immune genes (including TEP1, LRIM1, and APL1C), Toll pathway genes (including Tube, MyD88, and Rel1), and the effector defensin 1 were upregulated by DHA treatment at 24 and 72 hpi. TEP1 and Rel1 protein expression was significantly induced under DHA treatment. However, Rel1 knockdown in DHA-treated mosquitoes abrogated DHA-mediated refractoriness to Plasmodium infection.</p><p><strong>Conclusions: </strong>DHA treatment effectively inhibited the development of P. yoelii in A. stephensi by upregulating mosquitoes' Toll signaling pathway, thereby influencing the susceptibility of Anopheles to Plasmodium.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"414"},"PeriodicalIF":3.0,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11451267/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372529","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":"Human-to-Anopheles dirus mosquito transmission of the anthropozoonotic malaria parasite, Plasmodium knowlesi.","authors":"Chalermpon Kumpitak, Apisak Duangmanee, Waraporn Thongyod, Nattawan Rachaphaew, Chayanut Suansomjit, Khajohnpong Manopwisedjaroen, Pyae Linn Aung, Hisham Ahmed Imad, Liwang Cui, Jetsumon Sattabongkot, Wang Nguitragool, Sirasate Bantuchai","doi":"10.1186/s13071-024-06500-5","DOIUrl":"10.1186/s13071-024-06500-5","url":null,"abstract":"<p><strong>Background: </strong>Plasmodium knowlesi, identified as the fifth human malaria parasite, has rapidly spread across various Southeast Asian countries, yet uncertainties persist regarding its human-mosquito-human transmission. Therefore, this study aims to explore the transmission potential of P. knowlesi from human blood to mosquitoes.</p><p><strong>Methods: </strong>A direct membrane-feeding assay was conducted by infecting laboratory-reared female Anopheles dirus mosquitoes with P. knowlesi-infected human blood from a single patient presenting with febrile malaria. Mosquitoes were dissected 7 days post-infection under a stereomicroscope to detect oocysts in the midgut, stained with mercurochrome. Salivary glands were examined 14 days post-infection for the presence of sporozoites. Malaria diagnosis employed microscopy by expert microscopists and nested PCR assays.</p><p><strong>Results: </strong>Upon dissecting 745 out of 1439 blood-fed An. dirus mosquitoes on day 7 post-infection, two oocysts were identified in the midguts of two mosquitoes (0.27%). An additional 694 mosquitoes were dissected for salivary glands on day 14 post-infection, with three mosquitoes (0.43%) exhibiting sporozoites. Further confirmation by nested-PCR assay verified these sporozoites as belonging to the P. knowlesi species.</p><p><strong>Conclusions: </strong>The findings underscore the potential transmission of P. knowlesi from human blood to mosquitoes. The significance of these findings necessitates further investigation, such as repeating similar experiments among natural vectors, to gain deeper insights into the transmission dynamics of P. knowlesi in Southeast Asia.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"415"},"PeriodicalIF":3.0,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11451161/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142375714","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":"Feeding habits and malaria parasite infection of Anopheles mosquitoes in selected agroecological areas of Northwestern Ethiopia.","authors":"Aklilu K Belay, Abebe Asale, Catherine L Sole, Abdullahi A Yusuf, Baldwyn Torto, Clifford M Mutero, David P Tchouassi","doi":"10.1186/s13071-024-06496-y","DOIUrl":"10.1186/s13071-024-06496-y","url":null,"abstract":"<p><strong>Background: </strong>Surveillance of the host-anopheline mosquitoes' interaction is important for assessing malaria transmission risk and guiding vector control. We assume that changes in malaria vector species' feeding habits, as well as the surrounding environment, have a substantial impact on varied malaria transmission. In this study, we determined the vertebrate host feeding patterns of anopheline mosquitoes to characterize entomologic risk factors for malaria in Jabi Tehnan, Northwestern Ethiopia.</p><p><strong>Methods: </strong>Blood-fed anophelines surveyed during malaria surveillance in Jabi Tehnan district of northwestern Ethiopia were utilized in this study. They were collected using Centers for Disease Control and Prevention (CDC) light traps deployed in selected households per village, placed indoors and outdoors, spanning three agroecological settings (dry mountain, plateau, and semiarid highlands) between June 2020 and May 2021. The engorged mosquitoes were analyzed for host blood meal sources and Plasmodium infection via polymerase chain reaction (PCR) and/or sequencing. Infection rates and bovine and human blood indices were calculated and compared for abundant species; between indoors and outdoors and between agroecology using a chi-squared test for equality of proportion in R package at a significant level of p ≤ 0.05.</p><p><strong>Results: </strong>A total of 246 mosquitoes were successfully typed (indoor, 121; outdoor, 125), with greater relative abundance indoors in mountain and plateau highlands, and outdoors in semiarid areas. Despite ecological differences in blood-fed capture rates, cattle served as the most utilized blood meal source by 11 anopheline species with an overall bovine blood index (BBI) of 74.4%. This trend was dictated by Anopheles gambiae s.l. (198/246; BBI = 73.7%), which exhibited the most plastic feeding habits that included humans (human blood index = 15.7%) and other livestock and rodents. A total of five anopheline species (An. gambiae s.l., An. funestus s.l., An. coustani s.l., An. pretoriensis, and An. pharoensis) fed on humans, of which the first three were found infected with Plasmodium parasites. Most of the infected specimens were An. arabiensis (5.6%, 11/198) and had recently fed mainly on cattle (72.7%, 8/11); one each of infected An. funestus s.l. and An. coustani s.l. had fed on humans and cattle, respectively.</p><p><strong>Conclusions: </strong>The results demonstrate communal feeding on cattle by anophelines including primary and secondary malaria vectors. This study also indicates the importance of cattle-targeted interventions for sustainable control of malaria vectors in the study areas.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"412"},"PeriodicalIF":3.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11451063/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372530","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":"Schistosoma japonicum infection-mediated downregulation of lncRNA Malat1 contributes to schistosomiasis hepatic fibrosis by the Malat1/miR-96/Smad7 pathway.","authors":"Pengyue Jiang, Shengyu Ye, Xiaobin Fan, Yini Tian, Dongmei Zhang, Weiqing Pan","doi":"10.1186/s13071-024-06499-9","DOIUrl":"10.1186/s13071-024-06499-9","url":null,"abstract":"<p><strong>Background: </strong>Schistosoma japonicum infection causes hepatic fibrosis, a primary cause of morbidity and mortality associated with the disease, and effective treatments are still lacking. Long non-coding RNAs (lncRNAs) have been implicated in the pathogenic process of various tissue fibroses. However, the role of lncRNAs in schistosomiasis hepatic fibrosis (HF) is poorly understood. Understanding the role of lncRNAs in schistosomiasis HF will enhance knowledge of disease processes and aid in the discovery of therapeutic targets and diagnostic biomarkers.</p><p><strong>Methods: </strong>Differentially expressed lncRNA profiles in primary hepatic stellate cells (HSCs) of mice infected with S. japonicum were identified using high-throughput lncRNA sequencing. Primary HSCs were isolated from infected mice using collagenase digestion and density-gradient centrifugation, cultured in DMEM with 10% fetal bovine serum. Dual-luciferase reporter assays, nuclear cytoplasm fractionation and RIP assays were employed to assess the relationship between Malat1 and miRNA-96. Malat1 lentivirus and ASO-Malat1 were constructed for forced expression and downregulated expression of Malat1. The Malat1-KO mouse was constructed by CRISPR/Cas9 technology. Pathological features of the liver were evaluated by hematoxylin-eosin (HE), Masson's trichrome staining and immunohistochemistry (IHC). The expression levels of fibrosis-related genes were determined by quantitative real-time PCR (qRT-PCR) and Western blot.</p><p><strong>Results: </strong>A total of 1561 differentially expressed lncRNAs were identified between infected and uninfected primary HSCs. Among the top altered lncRNAs, the downregulated Malat1 was observed in infected HSCs and verified by qPCR. Treatment of infected mice with praziquantel (PZQ) significantly increased the Malat1 expression. Elevated Malat1 expression in infected primary HSC reduced the expressions of profibrogenic genes, whereas Malat1 knockdown had the opposite effect. Moreover, Malat1 was found to interact with miR-96, a profibrotic miRNA, by targeting Smad7. Forced Malat1 expression reduced miR-96 levels in infected primary HSCs, attenuating fibrogenesis and showing negative correlation between Malat1 expression and the expression levels of miR-96 and profibrogenic genes α-SMA and Col1α1. Notably, in Malat1-KO mice, knockout of Malat1 aggravates schistosomiasis HF, while restored Malat1 expression in the infected HSCs reduced the expression of profibrogenic genes.</p><p><strong>Conclusions: </strong>We demonstrate that lncRNA is involved in regulation of schistosomiasis HF. Elevated lncRNA Malat1 expression in infected HSCs reduces fibrosis via the Malat1/miR-96/Smad7 pathway, thus providing a novel therapeutic target for schistosomiasis HF. Furthermore, Malat1 expression is sensitive to PZQ treatment, thus offering a potential biomarker for assessing the response to chemotherapy.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"17 1","pages":"413"},"PeriodicalIF":3.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11451255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372532","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}