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

{"title":"Larvicidal activity of Bacillus thuringiensis strains against Aedes aegypti and Culex quinquefasciatus mosquitoes","authors":"Prakai Rajchanuwong ,&nbsp;Sawaporn Peaboon ,&nbsp;Ratchadawan Ngoen-Klan ,&nbsp;Atsalek Rattanawannee ,&nbsp;Atirat Noosidum ,&nbsp;Boonhiang Promdonkoy ,&nbsp;Jariya Chanpaisaeng ,&nbsp;Theeraphap Chareonviriyaphap","doi":"10.1016/j.crpvbd.2025.100245","DOIUrl":"10.1016/j.crpvbd.2025.100245","url":null,"abstract":"<div><div>Organophosphates, carbamates and synthetic pyrethroids are commonly used in Thailand to control mosquito vectors; however, long-term use of insecticides in vector control has led to the rapid development of insecticide resistance. In this study, we screened <em>Bacillus thuringiensis</em> strains as biological control agents for potential toxins against mosquito larvae as an additional control tool. Preliminary bioassays conducted on 434 strains demonstrated that 41 strains (11.64%) and 14 strains (3.97%) achieved 100% mortality against <em>Ae. aegypti</em> and <em>Cx. quinquefasciatus</em> larvae, respectively. Three strains (JC690, JC691, and JC699) showed toxicity to both mosquito species, compared with the reference Bti strain. Strains JC691 demonstrated the highest efficacy against <em>Ae. aegypti</em> and <em>Cx. quinquefasciatus</em>, with an LC₅₀ value of 6.96 × 10⁴ CFU/ml and 1.16 × 10³ CFU/ml, respectively. A comparison of LC₅₀ values revealed that JC691 exhibited higher efficacy against <em>Cx. quinquefasciatus</em> than that by Bti (Bti LC₅₀: 8.89 × 10⁴ CFU/ml) but lower efficacy against <em>Ae. aegypti</em> (Bti LC₅₀: 1.99 × 10³ CFU/ml). Scanning electron microscopy revealed that JC690, JC691, and JC699 are rod-shaped, have oval spores, and produce bi-pyramidal crystal proteins. Protein profile analysis using SDS-PAGE demonstrated distinct differences between these Thailand strains (JC690, JC691, and JC699) and the reference Bti strain. All three Thailand strains contained <em>cry</em>1I and <em>cry</em>2A genes, and only JC691 harbored the <em>cry</em>32 gene. Bayesian inference and maximum likelihood phylogenetic analyses of <em>cry</em>32 indicated that the partial sequences of <em>cry</em>32 in JC691 from Thailand were distinct from those of other <em>B. thuringiensis</em> strains from different countries. This study demonstrates the potential of JC690, JC691, and JC699 as biocontrol agents for <em>Ae. aegypti</em> and <em>Cx. quinquefasciatus</em>.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100245"},"PeriodicalIF":1.7,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into the transmission cycle of cutaneous leishmaniasis from an endemic community in rural Guatemala","authors":"Yaimie Lopez ,&nbsp;Aitor Casas-Sanchez ,&nbsp;Byron Arana ,&nbsp;Nidia Rizzo ,&nbsp;Erick Duran ,&nbsp;Norma Padilla ,&nbsp;Andrea de la Vega ,&nbsp;Esteban Bustamante ,&nbsp;Álvaro Acosta-Serrano ,&nbsp;Renata Mendizabal-Cabrera","doi":"10.1016/j.crpvbd.2025.100244","DOIUrl":"10.1016/j.crpvbd.2025.100244","url":null,"abstract":"<div><div>Cutaneous leishmaniasis (CL) is a parasitic vector-borne disease prevalent in 90 countries. Despite its endemicity in Guatemala, key transmission factors are still unknown. To address this, we characterized sand fly populations and <em>Leishmania</em> parasites in a Guatemalan community in 2022. We visited the households of 23 patients with lesions compatible with CL, sampled for sand flies and analysed <em>Leishmania</em> spp. presence in patients’ skin scrapings and in collected sand flies. We collected 93 sand flies, predominantly females including the vector species <em>Nyssomyia ylephiletor</em>, <em>Bichromomyia olmeca</em> and <em>Lutzomyia cruciata</em>. <em>Nyssomyia ylephiletor</em> was the most abundant species indoors. Four <em>Leishmania</em> spp. were identified including <em>L. panamensis</em>, <em>L. guyanensis</em>, <em>L. braziliensis</em> and <em>L. infantum</em> in CL lesions, <em>L. guyanensis</em> complex species (<em>L. guyanensis</em> or <em>L. panamensis</em>) and <em>Leishmania</em> sp. in sand flies. Sand fly species positive for <em>Leishmania</em> spp. were <em>Ny. ylephiletor</em>, <em>Dampfomyia deleoni</em>, <em>Dampfomyia</em> sp<em>.</em> and <em>Brumptomyia</em> sp. Blood-meal analysis revealed human and pig blood in engorged <em>Ny. ylephiletor</em> collected inside and in the proximity of the households. This is the first report of <em>L. guyanensis</em> in Guatemalan patients and provides insights into CL transmission dynamics, suggesting potential indoor transmission, pending more studies.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100244"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143360315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid review: Recent advances in in vitro models for the study of Cryptosporidium parvum","authors":"Mathilde S. Varegg,&nbsp;Ian D. Woolsey,&nbsp;Lucy J. Robertson,&nbsp;Alejandro Jiménez-Meléndez","doi":"10.1016/j.crpvbd.2025.100269","DOIUrl":"10.1016/j.crpvbd.2025.100269","url":null,"abstract":"<div><div><em>Cryptosporidium</em> research has been hampered by the lack of <em>in vitro</em> models that can recapitulate the life cycle of the parasite, thus relying on repeated animal infections. Traditional <em>in vitro</em> systems, employing cancerous cell lines, have been unable to support sexual reproduction, but have been widely employed for drug screening assays and allowed transcriptome mapping of the parasite, but extrapolation of those results to <em>in vivo</em> infections is limited. In recent years, intestinal organoids (enteroids), grown as 3D structures, have come to be recognized as more physiologically relevant, complex systems, since they more accurately reproduce the cell populations present in the small intestine. A key advantage of these systems is their ability to fulfil the life cycle of the parasite. However, studies employing bovine organoids, the target species of the major zoonotic species <em>Cryptosporidium parvum</em>, are lacking. Future research should emphasize bioengineered systems, with heterogeneous populations of intestinal epithelial and mesenchymal cells, to advance the <em>in vitro</em> field closer to <em>in vivo</em> infection models. The present review summarizes the history of cell line use in <em>Cryptosporidium</em> research and the most recent advances in organoids, bio-engineered and organ-on-a-chip platforms, including methodological approaches used to facilitate exposure of the apical side of the target cells to the parasite, and the influence of mechanical forces and microenvironment.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100269"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144116551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial and metabolic signatures among Blastocystis subtypes ST1-ST9 in xenic cultures","authors":"Daisy Shaw ,&nbsp;William J.S. Edwards ,&nbsp;Gary S. Thompson ,&nbsp;Martin Kolisko ,&nbsp;Eleni Gentekaki ,&nbsp;Anastasios D. Tsaousis","doi":"10.1016/j.crpvbd.2025.100317","DOIUrl":"10.1016/j.crpvbd.2025.100317","url":null,"abstract":"<div><div><em>Blastocystis</em> is the most prevalent intestinal protist in humans, yet its role in gut health remains poorly understood. Increasing evidence suggests subtype-specific interactions with the gut microbiome and metabolome may underlie its variable associations with health and disease. In this pilot study, we performed an integrated analysis of the microbiota and metabolite profiles of nine <em>Blastocystis</em> subtypes (ST1-ST9) grown <em>in vitro</em> using xenic cultures. Using 16S rRNA amplicon sequencing and proton nuclear magnetic resonance (¹H-NMR) metabolomics, we characterised the microbial communities and extracellular metabolites across subtypes. ST3 exhibited the most distinct microbiome and metabolomic profile, characterised by a significant enrichment of short-chain fatty acids (SCFAs) and amino-acid derivatives. Benzoate, a known antimicrobial, was uniquely downregulated in ST3. Linear discriminant analysis identified several bacterial genera, such as <em>Methanobrevibacter</em> and <em>Enterobacter</em>, as biomarkers for ST3. Correlations between key metabolites and microbial taxa suggest potential syntrophic interactions. These findings suggest that individual <em>Blastocystis</em> subtypes establish distinct microenvironments <em>in vitro</em>, with implications for their ecological roles <em>in vivo</em>. Our study provides a foundational framework for understanding subtype-specific biology and offers a platform for improving culture conditions and investigating host-microbe interactions.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100317"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145048752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Location intelligence unveils seasonal spatiotemporal pattern shifts of habitat use and selection by cattle across a South Texas coastal landscape infested with Rhipicephalus microplus","authors":"Taylor G. Donaldson ,&nbsp;Brian T. Rich ,&nbsp;Miranda R. Peterson ,&nbsp;Hsiao-Hsuan Wang ,&nbsp;William E. Grant ,&nbsp;Donald B. Thomas ,&nbsp;Kimberly H. Lohmeyer ,&nbsp;Adalberto Á. Pérez de León ,&nbsp;Pete D. Teel","doi":"10.1016/j.crpvbd.2025.100322","DOIUrl":"10.1016/j.crpvbd.2025.100322","url":null,"abstract":"<div><div>Knowledge gaps on the dynamics of cattle fever tick-cattle-habitat-climate interactions in South Texas and their influence on the efficacy of treatments to eliminate infestations with the <em>Rhipicephalus</em> (<em>Boophilus</em>) <em>microplus</em> prevent optimal interventions by the Cattle Fever Tick Eradication Program (CFTEP). The CFTEP has been operating in the USA since 1907. This study applied the concept of location intelligence to examine movement, habitat use and selection by cattle in a highly heterogeneous coastal landscape infested with <em>R. microplus</em>. Cattle interface with white-tailed deer and nilgai, which are alternate wildlife hosts of <em>R</em>. <em>microplus</em>, in this unique South Texas landscape. Location intelligence data obtained from GPS collars placed on steers between August and December 2019 that were treated as part of the protocol to eradicate <em>R. microplus</em> were used to track their movement in the tick-infested rangeland of the Laguna Atascosa National Wildlife Refuge. GIS spatial analyses were conducted to determine time-of-day (morning, midday, evening, midnight), and seasonal differences in: (i) distance of cattle movements; (ii) cattle habitat use and selection; (iii) spatial spread of cattle; and (iv) distance to closest watering site. Cattle movement patterns, habitat use and selection, spatial spread, and distance to closest watering sites were significantly different between the summer and autumn periods. These variables were also significantly different by time-of-day periods within and between seasonal periods. Habitat use and selection by steers are discussed in the context of range sites and vegetation types. Nine ixodid tick species were documented through the inspection of hosts (cattle, nilgai, and white-tailed deer). <em>Rhipicephalus microplus</em> was collected from white-tailed deer and nilgai during cull hunts, as well as from project cattle that missed one anti-tick treatment due to adverse weather conditions. Tick-host-habitat-climate interactions involving cattle and wildlife, future grazing strategies for anti-tick treated cattle, and potential impacts of tick-refugia are discussed in the context of location intelligence. Spatiotemporal patterns of cattle habitat use and selection across an infested coastal landscape in South Texas revealed by location intelligence could inform adaptive operations of the CFTEP to keep the USA free of <em>R</em>. <em>microplus</em>.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100322"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145219168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Species distribution and screening of Trypanosoma DNA in phlebotomine sand flies from four southern provinces of Thailand","authors":"Nantatchaporn Klaiklueng ,&nbsp;Rawadee Kumlert ,&nbsp;Sopavadee Moonmake ,&nbsp;Toon Ruang-areerate ,&nbsp;Padet Siriyasatien ,&nbsp;Sakone Sunantaraporn ,&nbsp;Darawan Wanachiwanawin ,&nbsp;Pichet Ruenchit ,&nbsp;Sirichit Wongkamchai","doi":"10.1016/j.crpvbd.2025.100263","DOIUrl":"10.1016/j.crpvbd.2025.100263","url":null,"abstract":"<div><div>Sand flies are principal vectors of <em>Leishmania</em> spp. and <em>Trypanosoma</em> spp. Identifying precise vector species is crucial for effective control. We conducted a study on the species distribution of phlebotomine sand flies in cave-dwelling and non-cave-dwelling in four southern provinces of Thailand. In this study, we collected 621 sand flies (346 females and 275 males) and identified all specimens based on morphology and DNA barcoding, employing cytochrome <em>c</em> oxidase subunit 1 (<em>cox</em>1) and cytochrome <em>b</em> (<em>cytb</em>) genes. In female specimens, we also screened the small subunit 18S ribosomal RNA (18S rRNA) gene for <em>Leishmania</em> spp. and <em>Trypanosoma</em> spp. Morphologically, 467 (75.2%) sand flies were identified to species level, 47 (7.57%) to subgenus level, and 107 (17.23%) to genus level. These included <em>Idiophlebotomus asperulus</em> (43.48%), <em>Sergentomyia khawi</em> (26.73%), <em>S. anodontis</em> (2.25%), <em>S. brevicaulis</em> (2.25%), <em>Grassomyia indica</em> (0.48%), <em>Phlebotomus</em> (<em>Euphlebotomus</em>) spp. (4.83%), <em>Phlebotomus</em> (<em>Lewisius</em>) spp. (2.74%), <em>Sergentomyia</em> spp. (9.18%), and <em>Phlebotomus</em> spp. (8.05%). Among the 107 specimens identified to genus level, DNA barcoding further identified 49 (45.79%) as <em>Sergentomyia barraudi</em> (1.61%), <em>S. bailyi</em> (0.16%), <em>Phlebotomus kiangsuensis</em> (2.9%), and <em>Ph. stantoni</em> (1.61%). No <em>Leishmania</em> DNA was detected, but <em>Trypanosoma</em> DNA was found in females of <em>S. khawi</em> from Narathiwat Province. Expanding genetic reference databases of sand flies located in four provinces of southern Thailand will improve barcoding accuracy. Understanding sand fly species composition and distribution is imperative for vector control and disease prevention in Thailand.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100263"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The BiteBarrier perimeter: A passive spatial device for tick control and bite prevention","authors":"Maria V. Murgia ,&nbsp;Laurie Widder ,&nbsp;Catherine A. Hill","doi":"10.1016/j.crpvbd.2025.100246","DOIUrl":"10.1016/j.crpvbd.2025.100246","url":null,"abstract":"<div><div>Tick-borne diseases (TBDs) impact human and animal health on a global scale. Prevention of TBDs relies primarily on prevention of tick bites. New bite-prevention technologies are needed as an alternative to current approaches such as topical repellents and treated clothing which suffer low user compliance. To date, no passive spatial devices have been commercialized for area protection against ticks. The BiteBarrier (formerly the Personal Insect Repellent Kit, PIRK), a passive, lightweight device that emits transfluthrin, offers to fill this gap. In a previous study, we demonstrated contact toxicity of the BiteBarrier substrate to three tick species, <em>Ixodes scapularis</em>, <em>Dermacentor variabilis</em> and <em>Amblyomma americanum</em>, and reported differences in efficacy depending on species and short-range spatial efficacy against <em>I. scapularis</em> adult females. Here, we extended analyses and demonstrated modest spatial activity of the BiteBarrier substrate against <em>A. americanum</em> and <em>D. variabilis</em> adult females. Using a dual-choice behavioral assay, we showed that the three tick species preferred an area of untreated substrate. Lastly, we present a novel perimeter assay, developed to assess the efficacy of the BiteBarrier ground-based prototype against ticks. At short-range in a Peet Grady-style chamber, the BiteBarrier perimeter induced greater than 90% knockdown of <em>I. scapularis</em> adult females at 1 and 2 h post-exposure and 90% mortality at 48 h post-exposure. Taken together, study findings indicate the potential of the BiteBarrier perimeter to control ticks at near range and potentially, to protect against tick bites.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100246"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring of questing tick species distribution in Galicia, north-western Spain, over a period of 5.5 years","authors":"María Vilá Pena ,&nbsp;Inês Abreu Ramos ,&nbsp;Génesis Bautista García ,&nbsp;Elvira Íñiguez Pichel ,&nbsp;Cristiana Cazapal Monteiro ,&nbsp;José Ángel Hernández Malagón ,&nbsp;Adolfo Paz Silva ,&nbsp;Rita Sánchez-Andrade Fernández ,&nbsp;María Sol Arias Vázquez","doi":"10.1016/j.crpvbd.2025.100254","DOIUrl":"10.1016/j.crpvbd.2025.100254","url":null,"abstract":"<div><div>An active survey was performed by the Galician Vector Surveillance Network (ReGaViVec) to determine the distribution of questing tick species in the Autonomous Community of Galicia Galicia, north-western Spain. Monitoring of tick populations involved drag/flag sampling at 533 locations over a period of 5.5 years. The identification of tick species, sex, and stage was carried out according to morphological keys, and the results were analyzed considering three Köppen climate regions, i.e. Cfb (marine west coast climate), Csb (warm-summer Mediterranean climate), and Csa (hot-summer Mediterranean climate), season, environment (forest, rural, or urban), vegetation height (≤ 15 cm, 16–40 cm, and &gt; 40 cm); and altitude (&lt; 300 m, 301–500 m, 501–1000 m, and &gt;1000 m). A total of 1378 ticks were collected at 260 locations: 62.92% in Csb, 24.38% in Cfb, and 12.70% in Csa. Of these, 2% were larvae, 45.2% were nymphs, and 52.8% were adults (58.3% females and 41.7% males). Six species were recorded, i.e. <em>Ixodes ricinus</em> (57.90%), <em>Rhipicephalus sanguineus</em> (<em>sensu lato</em>) (26.05%), <em>Dermacentor reticulatus</em> (10.95%), <em>Dermacentor marginatus</em> (2.10%), <em>Haemaphysalis</em> sp. (2.61%), and <em>Rhipicephalus bursa</em> (0.36%). A seasonal pattern was recorded, with the relative abundance of <em>I. ricinus</em> and <em>R. sanguineus</em> (<em>s.l</em>.) peaking in spring-summer, and that of <em>Dermacentor</em> spp. and <em>Haemaphysalis</em> sp. peaking in autumn-winter. Significant differences were demonstrated in the species abundance distribution according to climate region, season, environment, and altitude. The highest tick abundance was recorded in summer, in rural areas, and at altitudes of &lt; 300 m. Because most of the tick species present in the environment of Galicia have vectorial competence for emerging tick-borne pathogens, it is important to maintain research and coordination of tick surveillance practices in the region.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100254"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of seasonal change on virus-rodent dynamics in Nigeria’s Edo-Ondo hotspot for Lassa fever","authors":"Akinlabi Oyeyiola ,&nbsp;Adetunji Samuel Adesina ,&nbsp;Adeoba Obadare ,&nbsp;Joseph Igbokwe ,&nbsp;Samuel Ayobami Fasogbon ,&nbsp;Chukwuyem Abejegah ,&nbsp;Patience Akhilomen ,&nbsp;Danny Asogun ,&nbsp;Ekaete Tobin ,&nbsp;Olufemi Ayodeji ,&nbsp;Omolaja Osoniyi ,&nbsp;Meike Pahlmann ,&nbsp;Stephan Günther ,&nbsp;Elisabeth Fichet-Calvet ,&nbsp;Ayodeji Olayemi","doi":"10.1016/j.crpvbd.2025.100271","DOIUrl":"10.1016/j.crpvbd.2025.100271","url":null,"abstract":"<div><div>The zoonotic Lassa virus (LASV) is naturally maintained in rodents but commonly virulent in humans, killing thousands across West Africa annually. Human cases of Lassa fever surge during the dry season. In a hotspot for this disease, involving seven localities from Edo and Ondo states within Nigeria, we sought to depict how fluctuation patterns of LASV prevalence in rodents and levels of rodent infestation culminate in particularly heightened points of potential rodent-to-human transmission. We also explored how this variability may be driven by environmental and demographic factors. We determined active LASV infection by PCR and previous infection using an indirect immunofluorescence assay for IgG antibodies. Six out of the seven localities had active LASV infections, ranging between 3.7% (1/27) and 75.5% (37/49). In Ebudin and Ekpoma, where longitudinal sampling was conducted, prevalence differences were not statistically significant across locality, habitat, season, or year. Conversely, abundance peaked significantly indoors for <em>Mastomys natalensis</em> (the major LASV reservoir) and <em>Praomys daltoni</em> either during the dry or rainy season, depending on whether each of these rodent species occupied Ebudin or Ekpoma. Our results suggest that, since LASV occurrence is usually widespread in its natural reservoir within highly endemic areas, a more immediate component of zoonotic risk to prioritize for control would be the targeting of rodent infestation peaks when they occur inside human habitations. Over our two-year survey, these peaks in abundance were consistent in the months they occurred yearly for <em>M. natalensis</em> and <em>P. daltoni</em> per locality.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"7 ","pages":"Article 100271"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Midichloria mitochondrii stimulates the sylvatic cycle of Borrelia burgdorferi (sensu lato) in Ixodes ricinus and contributes to Lyme disease risk","authors":"Clara F. Köhler ,&nbsp;Maya L. Holding ,&nbsp;Manoj Fonville ,&nbsp;Ron P. Dirks ,&nbsp;Hans J. Jansen ,&nbsp;Sara Moutailler ,&nbsp;Aurélie Heckmann ,&nbsp;Jens Zarka ,&nbsp;Erik Matthysen ,&nbsp;Hein Sprong ,&nbsp;Aleksandra I. Krawczyk","doi":"10.1016/j.crpvbd.2025.100290","DOIUrl":"10.1016/j.crpvbd.2025.100290","url":null,"abstract":"<div><div>Sex and symbionts of arthropod vectors are potential modulators of infection with vector-borne pathogens. Here, we investigated the involvement of sex and presence of the bacterial symbiont <em>Midichloria mitochondrii</em> in immature stages of <em>Ixodes ricinus</em> ticks on the acquisition and abundance of the tick-borne spirochete <em>Borrelia burgdorferi</em> (<em>sensu lato</em>). There was no difference in the infection rate of <em>M. mitochondrii</em> between male and female larvae. The infection with <em>M. mitochondrii</em> but not tick sex increased the acquisition of <em>B. burgdorferi</em> (<em>s.l.</em>) by <em>I. ricinus</em> larvae feeding on naturally infected birds. The infection with <em>B. burgdorferi</em> (<em>s.l.</em>) in questing nymphs was positively associated with <em>M. mitochondrii</em>, but not with their sex. The infection rates of <em>M. mitochondrii</em> in field-collected ticks showed substantial spatial variation. In our field study, we observed that locations exhibiting higher <em>M. mitochondrii</em> prevalence in nymphs also have significantly higher infection rates with <em>B. burgdorferi</em> (<em>s.l.</em>). Thus, the <em>M. mitochondrii</em> symbiont appears to enhance the ability of immature <em>I. ricinus</em> ticks to acquire and/or maintain <em>B. burgdorferi</em> (<em>s.l.</em>) in nature and is therefore an additional factor that contributes to the spatial variation in Lyme disease risk.</div></div>","PeriodicalId":94311,"journal":{"name":"Current research in parasitology & vector-borne diseases","volume":"8 ","pages":"Article 100290"},"PeriodicalIF":1.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144581268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}