Publications by authors named "Bonnie Webster"

Background: Intestinal schistosomiasis was confirmed endemic in Mangochi District, Malawi, in May of 2018 following an unexpected encounter with discreet populations of Biomphalaria spp. freshwater snails during routine malacological surveillance activities. Since then, only limited malacological surveillance of Biomphalaria has been carried out, and so the distribution of Biomphalaria populations in this area is currently unclear.

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  • Researchers studied intestinal schistosomiasis caused by Schistosoma mansoni in children living along the southern shoreline of Lake Malawi, five years after a disease outbreak, using advanced diagnostic techniques.
  • They utilized various methods including microscopy and real-time PCR on fecal and urine samples to assess infection rates and found that the prevalence of S. mansoni varied greatly based on the diagnostic tool used.
  • The study highlighted that while fecal-egg microscopy had very low sensitivity, the point-of-care test showed moderate sensitivity depending on how results were interpreted, also revealing notable DNA presence of another species, S. haematobium, in the samples.
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Mass-drug administration (MDA) of human populations using praziquantel monotherapy has become the primary strategy for controlling and potentially eliminating the major neglected tropical disease schistosomiasis. To understand how long-term MDA impacts schistosome populations, we analysed whole-genome sequence data of 570 samples (and the closely related outgroup species, from eight countries incorporating both publicly-available sequence data and new parasite material. This revealed broad-scale genetic structure across countries but with extensive transmission over hundreds of kilometres.

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  • Researchers hybridized a human parasitic fluke with a livestock parasite in a lab setting, but the ecological extent of this hybridization is still uncertain in the wild.
  • Analysis of 34.6 million genetic variations from 162 samples across 18 African countries showed a significant genetic divide between northern and southern populations, with no recent hybridization evidence but signs of past admixture events.
  • The study found that while gene flow barriers exist, 15 introgressed genes are becoming fixed in northern populations, and certain genomic regions, especially on sex chromosomes, resist hybridization, highlighting the importance of interspecific hybridization in shaping the genetics of these medically and agriculturally significant parasites.
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Background: Urogenital schistosomiasis is caused by the parasitic trematode Schistosoma haematobium. Sensitive and specific point-of-care diagnostics are needed for elimination of this disease. Recombinase polymerase amplification (RPA) assays meet these criteria, and an assay to diagnose S.

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Background: Lymnaeid snails of the genus Austropeplea are an important vector of the liver fluke (Fasciola hepatica), contributing to livestock production losses in Australia and New Zealand. However, the species status within Austropeplea is ambiguous due to heavy reliance on morphological analysis and a relative lack of genetic data. This study aimed to characterise the mitochondrial genome of A.

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Introduction: Multiplathogen home-based self-sampling offers an opportunity to increase access to screening and treatment in endemic settings with high coinfection prevalence of sexually transmitted (HIV, human papillomavirus (HPV)) and non-sexually transmitted pathogens ()). Chronic coinfections may lead to disability (female genital schistosomiasis) and death (cervical cancer). The Zipime-Weka-Schista (Do self-testing sister!) study aims to evaluate the validity, acceptability, uptake, impact and cost-effectiveness of multipathogen self-sampling for genital infections among women in Zambia.

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Schistosomiasis is a neglected tropical disease (NTD) caused by infection with parasitic trematodes of the genus that can lead to debilitating morbidity and mortality. The World Health Organization recommend molecular xenomonitoring of spp. freshwater snail intermediate hosts of to identify highly focal intestinal schistosomiasis transmission sites and monitor disease transmission, particularly in low-endemicity areas.

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Improvements in diagnostics for schistosomiasis in both humans and snail hosts are priorities to be able to reach the World Health Organization (WHO) goal of eliminating the disease as a public health problem by 2030. In this context, molecular isothermal amplification tests, such as Recombinase Polymerase Amplification (RPA), are promising for use in endemic areas at the point-of-need for their accuracy, robustness, simplicity, and time-effectiveness. The developed recombinase polymerase amplification assay targeting the Schistosoma mansoni mitochondrial minisatellite region (SmMIT-RPA) was used to detect S.

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  • Zanzibar has made significant progress in schistosomiasis control, achieving a reduction in Schistosoma haematobium prevalence from over 50% to below 5% in 2020, improving the health of its population.
  • The systematic review of 153 records from 1928 to 2022 highlights key milestones, remaining challenges, and the importance of integrated interventions for the elimination of urogenital schistosomiasis.
  • With ongoing commitments and focused strategies, achieving the interruption of S. haematobium transmission by 2030 is a realistic goal, potentially influencing broader efforts across sub-Saharan Africa.
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Background: The use of applications involving single nucleotide polymorphisms (SNPs) has greatly increased since the beginning of the 2000s, with the number of associated techniques expanding rapidly in the field of molecular research. Tetra-primer amplification refractory mutation system-PCR (T-ARMS-PCR) is one such technique involving SNP genotyping. It has the advantage of amplifying multiple alleles in a single reaction with the inclusion of an internal molecular control.

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Schistosomiasis is a major neglected tropical disease targeted for elimination as a public health issue by 2030, however there is an urgent need for more sensitive and specific diagnostic tests suitable to resource-limited settings. Here we developed CATSH, a CRISPR-assisted diagnostic test for Schistosoma haematobium, utilising recombinase polymerase amplification, Cas12a-targeted cleavage and portable real-time fluorescence detection. CATSH showed high analytical sensitivity, consistent detection of a single parasitic egg and specificity for urogenital Schistosoma species.

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and , two sympatric freshwater snails found in temporal ponds in Senegal, were thought to be involved in the transmission of and/or . To better understand the role of these species in the transmission of human and animal species, and were collected in 2015, during a malacological survey, from a temporal pond in Niakhar, central Senegal. Snails were induced to shed cercariae on two consecutive days.

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Background: Accurate diagnosis followed by timely treatment is an effective strategy for the prevention of complications together with reducing schistosomiasis transmission. Recombinase Polymerase Amplification (RPA) is a simple, rapid, sensitive, and specific isothermal method with low resource needs. This research aimed at the development and optimisation of a real-time (RT) and a lateral flow (LF) RPA assay for the detection of .

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  • * A study conducted on two islands in Zanzibar (Pemba and Unguja) evaluated the effects of mass drug administration (MDA) alone and with additional interventions on Schistosoma haematobium genetic diversity over several years.
  • * Results showed limited differences in genetic diversity across different treatments, but considerable variation was noted between the islands, with Pemba exhibiting higher infection rates and fecundity rates than Unguja.
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Background: The Zanzibar Archipelago (Pemba and Unguja islands) is targeted for the elimination of human urogenital schistosomiasis caused by infection with Schistosoma haematobium where the intermediate snail host is Bulinus globosus. Following multiple studies, it has remained unclear if B. nasutus (a snail species that occupies geographically distinct regions on the Archipelago) is involved in S.

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Background: Female genital schistosomiasis (FGS) is a neglected and disabling gynecological disease that can result from infection with the parasitic trematode Schistosoma haematobium. Accurate diagnosis of FGS is crucial for effective case management, surveillance and control. However, current methods for diagnosis and morbidity assessment can be inaccessible to those at need, labour intensive, costly and unreliable.

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  • A parasitic trematode that infects ungulates is causing significant health issues and economic losses in Sub-Saharan Africa, particularly affecting cattle with bovine intestinal schistosomiasis.
  • The recent discovery of this infection on Pemba Island, Tanzania, raises concerns about livestock and wildlife health in the region.
  • Research involving fresh faecal samples from local cattle confirmed the presence of the parasite, indicating that transmission is established, likely due to livestock trade with East Africa, and highlights the need for better diagnostic methods to monitor the situation.
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The last decades have brought important insight and updates in the diagnosis, management and immunopathology of female genital schistosomiasis (FGS) and male genital schistosomiasis (MGS). Despite sharing a common parasitic aetiological agent, FGS and MGS have typically been studied separately. Infection with Schistosoma haematobium manifests with gender-specific clinical manifestations and consequences of infection, albeit having a similar pathogenesis within the human genital tract.

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Urogenital schistosomiasis is caused by the blood fluke Schistosoma haematobium and is one of the most neglected tropical diseases worldwide, afflicting > 100 million people. It is characterised by granulomata, fibrosis and calcification in urogenital tissues, and can lead to increased susceptibility to HIV/AIDS and squamous cell carcinoma of the bladder. To complement available treatment programs and break the transmission of disease, sound knowledge and understanding of the biology and ecology of S.

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  • - Schistosoma mansoni, a blood fluke transmitted by snails, was brought to the Americas from Africa during the Trans-Atlantic slave trade, leading researchers to study its adaptation to local snail hosts and the effects on its population genetics.
  • - Analysis of genetic variants from S. mansoni in both regions revealed a significant reduction in genetic diversity during colonization, yet no strong population bottleneck, indicating that S. mansoni adapted well to the new environment.
  • - The study identified regions of the genome undergoing selection in the Americas, suggesting adaptations occurred during colonization, and inferred that unsampled central African populations were likely major sources for the S. mansoni found in Brazil.
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  • Schistosomiasis is a significant public health issue in sub-Saharan Africa, with control programs depending on effective mapping and widespread drug distribution, while hybridization between certain schistosoma species complicates these efforts.
  • Research in Cameroon shows that urogenital schistosomiasis, mostly caused by Schistosoma haematobium and its hybrids, has become more common than intestinal schistosomiasis, which is linked to Schistosoma guineensis.
  • A genome-wide study using RADseq revealed hybrid populations of S. guineensis and S. haematobium in Cameroon but not on São Tomé, suggesting varying dynamics in hybridization across regions, while also indicating
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  • - Mass drug administration with praziquantel (PZQ) is the primary method used to control schistosomiasis, but many parasites show reduced sensitivity to the drug, leading researchers to study the genetic factors behind this resistance in a specific PZQ-selected population.
  • - The study identified a gene related to a transient receptor potential (TRPM) channel that influences how schistosomiasis parasites respond to PZQ, revealing a significant difference in PZQ resistance levels between resistant and sensitive parasite populations.
  • - By analyzing genetic variations in the TRPM channel across different global parasite samples, researchers discovered a mutation that prevents PZQ from binding, highlighting the need for monitoring these resistant strains in efforts to eliminate schistos
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Long non-coding, tandem-repetitive regions in mitochondrial (mt) genomes of many metazoans have been notoriously difficult to characterise accurately using conventional sequencing methods. Here, we show how the use of a third-generation (long-read) sequencing and informatic approach can overcome this problem. We employed Oxford Nanopore technology to sequence genomic DNAs from a pool of adult worms of the carcinogenic parasite, , and used an informatic workflow to define the complete mt non-coding region(s).

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