scholarly journals Ancient hybridization and introgression of an invadolysin gene in schistosome parasites

2019 ◽  
Author(s):  
Roy N. Platt ◽  
Marina McDew-White ◽  
Winka Le Clec’h ◽  
Frederic D. Chevalier ◽  
Fiona Allan ◽  
...  
Keyword(s):  
Life History ◽  
Schistosoma Haematobium ◽  
Life History Traits ◽  
Single Gene ◽  
Sub Saharan Africa ◽  
Urogenital Schistosomiasis ◽  
Introgression Event ◽  
Sub Saharan ◽  
Hybridization And Introgression ◽  
Ancient Hybridization

The parasitic blood fluke Schistosoma haematobium causes urogenital schistosomiasis in humans and is a major cause of morbidity and mortality across sub-Saharan Africa. S. haematobium hybridizes with livestock schistosomes, including S. bovis, however the frequency, direction, age and genomic consequences of hybridization are unknown. We sequenced 96 S. haematobium exomes from Niger and the Zanzibar archipelago. and found evidence of an ancient, introgression event between Nigerien S. haematobium and S. bovis occurring 108-613 generations ago. Between 3.3-8.2% of Nigerien S. haematobium genomes are derived from S. bovis alleles, some of which show signatures of directional selection; the strongest signal spans a single gene in the invadolysin gene family, an M8 metalloprotease associated with parasitic life-history traits.

scholarly journals Ancient Hybridization and Adaptive Introgression of an Invadolysin Gene in Schistosome Parasites

2019 ◽  
Vol 36 (10) ◽  
pp. 2127-2142 ◽  
Author(s):  
Roy N Platt ◽  
Marina McDew-White ◽  
Winka Le Clec’h ◽  
Frédéric D Chevalier ◽  
Fiona Allan ◽  
...  
Keyword(s):  
High Frequency ◽  
Parasite Species ◽  
Single Gene ◽  
Sub Saharan Africa ◽  
Species Boundaries ◽  
Urogenital Schistosomiasis ◽  
Adaptive Introgression ◽  
Introgression Event ◽  
Sub Saharan ◽  
Ancient Hybridization

Abstract Introgression among parasite species has the potential to transfer traits of biomedical importance across species boundaries. The parasitic blood fluke Schistosoma haematobium causes urogenital schistosomiasis in humans across sub-Saharan Africa. Hybridization with other schistosome species is assumed to occur commonly, because genetic crosses between S. haematobium and livestock schistosomes, including S. bovis, can be staged in the laboratory, and sequencing of mtDNA and rDNA amplified from microscopic miracidia larvae frequently reveals markers from different species. However, the frequency, direction, age, and genomic consequences of hybridization are unknown. We hatched miracidia from eggs and sequenced the exomes from 96 individual S. haematobium miracidia from infected patients from Niger and the Zanzibar archipelago. These data revealed no evidence for contemporary hybridization between S. bovis and S. haematobium in our samples. However, all Nigerien S. haematobium genomes sampled show hybrid ancestry, with 3.3–8.2% of their nuclear genomes derived from S. bovis, providing evidence of an ancient introgression event that occurred at least 108–613 generations ago. Some S. bovis-derived alleles have spread to high frequency or reached fixation and show strong signatures of directional selection; the strongest signal spans a single gene in the invadolysin gene family (Chr. 4). Our results suggest that S. bovis/S. haematobium hybridization occurs rarely but demonstrate profound consequences of ancient introgression from a livestock parasite into the genome of S. haematobium, the most prevalent schistosome species infecting humans.

scholarly journals Cytological and Wet Mount Microscopic Observations Made in Urine of Schistosoma haematobium-Infected Children: Hint of the Implication in Bladder Cancer

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Patience B. Tetteh-Quarcoo ◽  
Benjamin K. Akuetteh ◽  
Irene A. Owusu ◽  
Solomon E. Quayson ◽  
Simon K. Attah ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Schistosoma Haematobium ◽  
Inflammatory Cells ◽  
Sub Saharan Africa ◽  
Urine Samples ◽  
Urogenital Schistosomiasis ◽  
Cytological Abnormalities ◽  
Sub Saharan ◽  
Carcinoma Of The Bladder ◽  
Infected Urine

Background. Schistosomiasis is the second major human parasitic disease next to malaria, in terms of socioeconomic and public health consequences, especially in sub-Saharan Africa. Schistosoma haematobium (S. haematobium) is a trematode and one of the species of Schistosoma that cause urogenital schistosomiasis (urinary schistosomiasis). Although the knowledge of this disease has improved over the years, there are still endemic areas, with most of the reported cases in Africa, including Ghana. Not much has been done in Ghana to investigate cytological abnormalities in individuals within endemic communities, although there are epidemiologic evidences linking S. haematobium infection with carcinoma of the bladder. Aim. The aim of this study was to identify microscopic and cytological abnormalities in the urine deposits of S. haematobium-infected children. Methodology. Three hundred and sixty-seven (367) urine samples were collected from school children in Zenu and Weija communities. All the samples were examined microscopically for the presence of S. haematobium eggs, after which the infected samples and controls were processed for cytological investigation. Results. S. haematobium ova were present in 66 (18.0%) out of the 367 urine samples. Inflammatory cells (82%, 54/66), hyperkeratosis (47%, 31/66), and squamous cell metaplasia (24%, 16/66) were the main observations made during the cytological examination of the S. haematobium-infected urine samples. Conclusion. Cytological abnormalities in S. haematobium-infected children may play an important role in the severity of the disease, leading to the possible development of bladder cancer in later years, if early attention is not given. Therefore, routine cytological screening for urogenital schistosomiasis patients (especially children) at hospitals in S. haematobium-endemic locations is recommended.

scholarly journals High prevalence of Schistosoma haematobium × Schistosoma bovis hybrids in schoolchildren in Côte d'Ivoire

Parasitology ◽  
2019 ◽  
Vol 147 (3) ◽  
pp. 287-294 ◽  
Author(s):  
Etienne K. Angora ◽  
Jean-François Allienne ◽  
Olivier Rey ◽  
Hervé Menan ◽  
André O. Touré ◽  
...  
Keyword(s):  
Cote D'ivoire ◽  
Schistosoma Haematobium ◽  
Côte D’Ivoire ◽  
Sub Saharan Africa ◽  
Cote D’Ivoire ◽  
Mitochondrial Cox1 ◽  
Fta Cards ◽  
Côte D'ivoire ◽  
High Prevalence ◽  
Sub Saharan

AbstractSchistosomiasis is a neglected tropical disease, though it is highly prevalent in many parts of sub-Saharan Africa. While Schistosoma haematobium-bovis hybrids have been reported in West Africa, no data about Schistosoma hybrids in humans are available from Côte d'Ivoire. This study aimed to identify and quantify S. haematobium-bovis hybrids among schoolchildren in four localities of Côte d'Ivoire. Urine samples were collected and examined by filtration to detect Schistosoma eggs. Eggs were hatched and 503 miracidia were individually collected and stored on Whatman® FTA cards for molecular analysis. Individual miracidia were molecularly characterized by analysis of mitochondrial cox1 and nuclear internal transcribed spacer 2 (ITS 2) DNA regions. A mitochondrial cox1-based diagnostic polymerase chain reaction was performed on 459 miracidia, with 239 (52.1%) exhibiting the typical band for S. haematobium and 220 (47.9%) the S. bovis band. The cox1 and ITS 2 amplicons were Sanger sequenced from 40 randomly selected miracidia to confirm species and hybrids status. Among the 33 cox1 sequences analysed, we identified 15 S. haematobium sequences (45.5%) belonging to seven haplotypes and 18 S. bovis sequences (54.5%) belonging to 12 haplotypes. Of 40 ITS 2 sequences analysed, 31 (77.5%) were assigned to pure S. haematobium, four (10.0%) to pure S. bovis and five (12.5%) to S. haematobium-bovis hybrids. Our findings suggest that S. haematobium-bovis hybrids are common in Côte d'Ivoire. Hence, intense prospection of domestic and wild animals is warranted to determine whether zoonotic transmission occurs.

scholarly journals Evaluating survey designs for targeting preventive chemotherapy against Schistosoma haematobium and Schistosoma mansoni across Sub-Saharan Africa: a geostatistical analysis and modelling study

2020 ◽  
Author(s):  
Kimberly Fornace ◽  
Claudio Fronterrè ◽  
Fiona M Fleming ◽  
Hope Simpson ◽  
Honorat Zoure ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Schistosoma Haematobium ◽  
Sampling Strategy ◽  
Sub Saharan Africa ◽  
Spatial Distributions ◽  
Preventive Chemotherapy ◽  
School Based ◽  
Control Programmes ◽  
Sub Saharan ◽  
Survey Designs

Abstract Background: Schistosomiasis control programmes primarily use school-based surveys to identify areas for mass drug administration of preventive chemotherapy. However, as the spatial distribution of schistosomiasis can be highly focal, transmission may not be detected by surveys implemented at districts or larger spatial units. Improved mapping strategies are required to accurately and cost-effectively target preventive chemotherapy to remaining foci across all possible spatial distributions of schistosomiasis. Methods: Here, we use geostatistical models to quantify the spatial heterogeneity of Schistosoma haematobium and S. mansoni across sub-Saharan Africa using the most comprehensive dataset available on school-based surveys. Applying this information to parameterise simulations, we assess the accuracy and cost of targeting alternative implementation unit sizes across the range of plausible schistosomiasis distributions. We evaluate the consequences of decisions based on survey designs implemented at district and subdistrict levels sampling different numbers of schools. Cost data were obtained from field surveys conducted across multiple countries and years, with cost effectiveness evaluated as the cost per correctly identified school. Results: Models identified marked differences in prevalence and spatial distributions between countries and species; however, results suggest implementing surveys at subdistrict level increase the accuracy of treatment classifications across most scenarios. While sampling intensively at the subdistrict level resulted in the highest classification accuracy, this sampling strategy resulted in the highest costs. Alternatively, sampling the same numbers of schools currently recommended at the district level but stratifying by subdistrict increased cost effectiveness.Conclusions: This study provides a new tool to evaluate schistosomiasis survey designs across a range of transmission settings. Results highlight the importance of considering spatial structure when designing sampling strategies, illustrating that a substantial proportion of children may be undertreated even when an implementation unit is correctly classified. Control programmes need to weigh the increased accuracy of more detailed mapping strategies against the survey costs and treatment priorities.

scholarly journals Life History of the Golden Puddle Frog, Phrynobatrachus auritus Boulenger 1900 (Anura: Phrynobatrachidae)

2016 ◽  
Vol 8 (3) ◽  
pp. 77
Author(s):  
Geraud Canis Tasse Taboue ◽  
Eric Bertrand Fokam
Keyword(s):  
Life History ◽  
Development Time ◽  
Captive Breeding ◽  
Sub Saharan Africa ◽  
Advertisement Call ◽  
Calling Behaviour ◽  
Number Of Factors ◽  
History Of ◽  
Sub Saharan

Frogs of the genus <em>Phrynobatrachus </em>Günther, 1862 are endemic to sub-Saharan Africa. These are increasingly threatened by a number of factors and are believed to be declining. We report on captive breeding experiments involving <em>Phrynobatrachus auritus</em> Boulenger, 1900. We provide a comprehensive life history for this frog with emphasize on tadpole development time, as well as a description of both the advertisement call and calling behaviour of the adult.

Determinants of genetic structure of the Sub-Saharan parasitic wasp Cotesia sesamiae

2017 ◽  
Author(s):  
Antoine Branca ◽  
Bruno Le Ru ◽  
Paul-André Calatayud ◽  
Julius Obonyo ◽  
Boaz Muzyoka ◽  
...  
Keyword(s):  
Biological Control ◽  
Life History ◽  
Genetic Structure ◽  
Parasitic Wasp ◽  
Sub Saharan Africa ◽  
Host Specialization ◽  
Life History Strategies ◽  
Cotesia Sesamiae ◽  
Sub Saharan ◽  
Different Strains

AbstractParasitoid life style represents one of the most diversified life history strategies on earth. There are however very few studies on the variables associated with intraspecific diversity of parasitoid insects, especially regarding the relationship with spatial, biotic and abiotic ecological factors. Cotesia sesamiae is a Sub-Saharan stenophagous parasitic wasp that parasitizes several African stemborer species with variable developmental success. The different host-specialized populations are infected with different strains of Wolbachia, an endosymbiotic bacterium widespread in arthropods that is known for impacting life history traits notably reproduction, and consequently species distribution. In this study, first we analyzed the genetic structure of C. sesamiae across Sub-Saharan Africa, using 8 microsatellite markers, and 3 clustering software. We identified five major population clusters across Sub-Saharan Africa, which probably originated in East African Rift region and expanded throughout Africa in relation to host genus and abiotic factors such as climatic classifications. Using laboratory lines, we estimated the incompatibility between the different strains of Wolbachia infecting C. sesamiae. We observed an incompatibility between Wolbachia strains was asymmetric; expressed in one direction only. Based on these results, we assessed the relationships between direction of gene flow and Wolbachia infections in the genetic clusters. We found that Wolbachia-induced reproductive incompatibility was less influential than host specialization in the genetic structure. Both Wolbachia and host were more influential than geography and current climatic conditions. These results are discussed in the context of African biogeography, and co-evolution between Wolbachia, virus parasitoid and host, in the perspective of improving biological control efficiency through a better knowledge of the biodiversity of biological control agents.

scholarly journals Correction to: The diagnosis and treatment of urogenital schistosomiasis in Italy in a retrospective cohort of immigrants from Sub-Saharan Africa

Infection ◽  
2019 ◽  
Vol 47 (3) ◽  
pp. 461-462
Author(s):  
Marta Tilli ◽  
Federico Gobbi ◽  
Francesca Rinaldi ◽  
Jacopo Testa ◽  
Silvio Caligaris ◽  
...  
Keyword(s):  
Retrospective Cohort ◽  
Sub Saharan Africa ◽  
Diagnosis And Treatment ◽  
Urogenital Schistosomiasis ◽  
Sub Saharan

scholarly journals Spatially varying selection shapes life history clines among populations of Drosophila melanogaster from sub-Saharan Africa

2015 ◽  
Vol 28 (4) ◽  
pp. 826-840 ◽  
Author(s):  
D. K. Fabian ◽  
J. B. Lack ◽  
V. Mathur ◽  
C. Schlötterer ◽  
P. S. Schmidt ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Life History ◽  
Sub Saharan Africa ◽  
Sub Saharan ◽  
Spatially Varying ◽  
Spatially Varying Selection

scholarly journals Switch between Life History Strategies Due to Changes in Glycolytic Enzyme Gene Dosage inSaccharomyces cerevisiae

2010 ◽  
Vol 77 (2) ◽  
pp. 452-459 ◽  
Author(s):  
Shaoxiao Wang ◽  
Aymé Spor ◽  
Thibault Nidelet ◽  
Pierre Montalent ◽  
Christine Dillmann ◽  
...  
Keyword(s):  
Life History ◽  
Cell Size ◽  
Carrying Capacity ◽  
Life History Traits ◽  
Gene Dosage ◽  
Single Gene ◽  
Glycolytic Enzyme ◽  
Life History Strategies ◽  
Glucose Consumption Rate ◽  
Glycolytic Gene

ABSTRACTAdaptation is the process whereby a population or species becomes better fitted to its habitat through modifications of various life history traits which can be positively or negatively correlated. The molecular factors underlying these covariations remain to be elucidated. UsingSaccharomyces cerevisiaeas a model system, we have investigated the effects on life history traits of varying the dosage of genes involved in the transformation of resources into energy. Changing gene dosage for each of three glycolytic enzyme genes (hexokinase 2, phosphoglucose isomerase, and fructose-1,6-bisphosphate aldolase) resulted in variation in enzyme activities, glucose consumption rate, and life history traits (growth rate, carrying capacity, and cell size). However, the range of effects depended on which enzyme was expressed differently. Most interestingly, these changes revealed a genetic trade-off between carrying capacity and cell size, supporting the discovery of two extreme life history strategies already described in yeast populations: the “ants,” which have lower glycolytic gene dosage, take up glucose slowly, and have a small cell size but reach a high carrying capacity, and the “grasshoppers,” which have higher glycolytic gene dosage, consume glucose more rapidly, and allocate it to a larger cell size but reach a lower carrying capacity. These results demonstrate antagonist pleiotropy for glycolytic genes and show that altered dosage of a single gene drives a switch between two life history strategies in yeast.

scholarly journals Three monthly doses of 60 mg/kg praziquantel for Schistosoma haematobium infection is a safe and effective treatment regimen.

2020 ◽  
Author(s):  
Samuel Nkansah Darko ◽  
Henry Hanson ◽  
Sampson Twumasi Ankrah ◽  
Sandra Baffour ◽  
Priscilla Adjei-Kusi ◽  
...  
Keyword(s):  
Renal Function ◽  
Schistosoma Haematobium ◽  
Post Treatment ◽  
Sub Saharan Africa ◽  
Gamma Glutamyl Transferase ◽  
Disease Epidemiology ◽  
Sub Saharan ◽  
Pre Treatment ◽  
And Gender ◽  
Glutamyl Transferase

Abstract Background Praziquantel (PZQ) is the standard treatment for Schistosomiasis in sub-Saharan Africa. However, there is evidence suggesting praziquantel treatment failure in Schistosome infections with associated potential renal impairment. The objective of this study was to determine the effect of three monthly doses of 60 mg/kg/day PZQ on schistosome egg count, liver and renal function during the treatment of urinary schistosomiasis in Ghana. Methods A nested case-control study was designed from a cohort screened for schistosomiasis; 28 schistosomiasis positive cases by microscopy matched with 53 healthy controls by age and gender. The study population was urban dwellers from the Asokwa sub-metropolitan area, Kumasi in Ghana. Participants were within the age range of 6 to 30 years. We assessed Schistosoma haematobium egg counts in urine and its associated impact on liver and renal function at baseline, treatment and post-treatment phases using serum. Results Of the 28 cases and 53 controls, 78.6% and (81.1% were males respectively. Globulin levels before treatment was higher in cases [36.7 (32.8, 40.1) vrs 30.5 (22.4, 33.8) , p=0.005] at pre-treatment but not at post-treatment [35.8 (31.2, 39.1)vrs 37.4 (29.7, 43.0), p= 0.767]. Estimated cure rate was 42.9%, 46.4% and 96.4% after first, second and third dose respectively. Schistosome egg counts dropped significantly (p= 0.001) from before second dose to post-treatment. Similarly, levels of alanine aminotransferase (p=0.001), aspartate aminotransferase (p=0.028) and gamma glutamyl transferase (p=0.001) significantly declined towards post-treatment. Estimated glomerular filtration rate significantly improved from before second dose to post-treatment using both the Chronic Kidney Disease Epidemiology Program (p=0.001) and 4-variable Modification of Diet in Renal Disease (p=0.002) equations. Conclusion Treatment of urinary Schistosoma hematobium infections with a repeated high monthly dose of 60 mg/kg of praziquantel for 3 months is safe and effective.

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