Bulinus truncatus

About: Bulinus truncatus is a research topic. Over the lifetime, 414 publications have been published within this topic receiving 5640 citations.

Effect of water plants and non-target snails on the infectivity of Bulinus truncatus with Schistosoma haematobium.

Abstract: The application of the water plant (Ceratophyllum demersum, Eichhornia crassipes and Lemna gibba) and/or non-target snails (Planorbis planorbis, Physa acuta and Melanoides tuberculata) gave a significant degree of reduction in the infection rate of B. truncatus subjected to S. haematobium miracidia. The data also indicated a reduction in mean total number of cercarial production/snail. However, no significant difference was detected in the prepatent period and duration of cercarial shedding of the parasite when compared with the control group. So, the results revealed that the snails exhibited a competitive ability against B. truncatus. Both survival rate and egg production of B. truncatus were greatly reduced when existed in mixed cultures with non-target snails and the magnitude of this reduction increased by increasing the number of the non-target snails.

Schistosomiasis in the Finchaa River Valley, Wellega Region, western Ethiopia

Abstract: : Parasitological and malacological surveys were carried out in the Finchaa Valley, Wellega Region, western Ethiopia Stool examination of 960 persons in the 10 communities surveyed showed an average human prevalence of 124% for Schistosoma mansoni Infected individuals were present in 6 communities, but prevalence was greater than 10% in only three of them, reaching 40% among school children in one community In endemic localities, the intensity of infection in terms of eggs per gram of faeces were 200 and 199 among school children and farm labours respectively The age specific prevalence and intensity of infection were highest among the 5-14 year age group The intermediate host of S mansoni, Biomphalaria pfeifferi were collected from three sites, but transmission was identified at only one site located in the lower portion of the valley Bulinus truncatus, the potential intermediate host of S haematobium in Ethiopia, was also present in the area The occurrence of infected human subjects and snail intermediate host confirm that Schistosoma mansoni is well established in the valley, particularly in the lower portion where a large irrigation development is under way In this report, the threat posed by both S Mansoni and S haematobium is discussed and the preventive/control measures to be taken are suggested [Ethiop J Health Dev 1993; 7(1):9-15]

The freshwater snail Bulinus tropicus (Planorbidae) in Namibia, characterised according to chromosome number, enzymes and morphology

Abstract: Freshwater snails collected in central Namibia, south-western Africa, from 15 populations belonging to the Bulinus truncatus/tropicus complex (Planorbidae) are characterised in respect of their chromosome number, morphology, egg proteins and enzymes. The population samples were all consistently diploid and euphallic. The findings are compared with observations on this group of snails in other areas of Africa. It is concluded that the Namibian populations belong to a single species, B. tropicus (Krauss, 1848), of which B. parietalis (Mousson, 1887) is probably a synonym. No evidence was found of any occurrence of the tetraploid species B. truncatus or of snails belonging to the B. africanus group; lack of a potential intermediate host therefore precludes transmission of Schistosoma haematobium in this area.

Molecular diversity of Bulinus species in Madziwa area, Shamva district in Zimbabwe: implications for urogenital schistosomiasis transmission

Abstract: Bulinus species are freshwater snails that transmit the parasitic trematode Schistosoma haematobium. Despite their importance, the diversity of these intermediate host snails and their evolutionary history is still unclear in Zimbabwe. Bulinus globosus and B. truncatus collected from a urogenital schistosomiasis endemic region in the Madziwa area of Zimbabwe were characterized using molecular methods. Malacological survey sites were mapped and snails were collected from water contact sites in four communities in the Madziwa area, Shamva district for a period of one year, at three-month intervals. Schistosoma haematobium infections in snails were determined by cercarial shedding and the partial mitochondrial cytochrome c oxidase subunit 1 gene (cox1) was used to investigate the phylogeny and genetic variability of the Bulinus spp. collected. Among the 1570 Bulinus spp. snails collected, 30 (1.9%) B. globosus were shedding morphologically identified schistosomes. None of the B. truncatus snails were shedding. The mitochondrial cox1 data from 166 and 16 samples for B. globosus and B. truncatus, respectively, showed genetically diverse populations within the two species. Twelve cox1 haplotypes were found from the 166 B. globosus samples and three from the 16 B. truncatus samples with phylogenetic analysis showing that the haplotypes fall into well-supported clusters within their species groups. Both B. truncatus and B. globosus clustered into two distinct lineages. Overall, significant negative values for both Tajima’s D statistic and the Fu’s Fs statistic were observed for B. globosus and B. truncatus. The study provided new insights into the levels of genetic diversity within B. globosus and additional information on B. truncatus collected from a small geographical area in Zimbabwe. Low prevalence levels of infection observed in the snails may reflect the low transmission level of urogenital schistosomiasis in the area. Our results contribute towards the understanding of the distribution and population genetic structure of Bulinus spp. supporting the mapping of the transmission or risk of transmission of urogenital schistosomiasis, particularly in Zimbabwe.