scholarly journals Effect of Mass Chemotherapy and Piped Water on Numbers of Schistosoma Haematobium and Prevalence in Bulinus Globosus in Kwale, Kenya

1988 ◽  
Vol 38 (3) ◽  
pp. 487-495 ◽  
Author(s):  
Shinichi Noda ◽  
Yoshiki Aoki ◽  
Atsuo Sato ◽  
Ngethe D. Muhoho ◽  
John H. Ouma ◽  
...  
Keyword(s):  
Schistosoma Haematobium ◽  
Piped Water ◽  
Bulinus Globosus

scholarly journals Mastomys natalensis (Smith, 1834) as a natural host for Schistosoma haematobium (Bilharz, 1852) Weinland, 1858 x Schistosoma bovis Sonsino, 1876 introgressive hybrids

2021 ◽  
Author(s):  
Boris A.E.S. Savassi ◽  
Gauthier Dobigny ◽  
Jonas R. Etougbétché ◽  
Thalasse T. Avocegan ◽  
François T. Quinsou ◽  
...  
Keyword(s):  
Definitive Host ◽  
Schistosoma Haematobium ◽  
Rattus Rattus ◽  
Introgressive Hybridization ◽  
Mastomys Natalensis ◽  
New Host ◽  
Time Period ◽  
Schistosoma Bovis ◽  
Bulinus Globosus ◽  
Internal Transcribed Spacer Rdna

AbstractCercarial emission of schistosomes is a determinant in the transmission to the definitive host and constitutes a good marker to identify which definitive host is responsible for transmission, mainly in introgressive hybridization situations. Our goal was to test the hypothesis that micro-mammals play a role in Schistosoma haematobium, S. bovis, and/or S. haematobium x S. bovis transmission. Small mammal sampling was conducted in seven semi-lacustrine villages of southern Benin. Among the 62 animals trapped, 50 individuals were investigated for Schistosoma adults and eggs: 37 Rattus rattus, 3 Rattus norvegicus, 9 Mastomys natalensis, and 1 Crocidura olivieri. Schistosoma adults were found in four R. rattus and two M. natalensis, with a local prevalence reaching 80% and 50%, respectively. Two cercarial chronotypes were found from Bulinus globosus experimentally infected with miracidia extracted from naturally infected M. natalensis: a late diurnal and nocturnal chronotype, and an early diurnal, late diurnal, and nocturnal chronotype. The cytochrome C oxidase subunit I mtDNA gene of the collected schistosomes (adults, miracidia, and cercariae) belonged to the S. bovis clade. Eleven internal transcribed spacer rDNA profiles were found; four belonged to S. bovis and seven to S. haematobium x S. bovis. These molecular results together with the observed multi-peak chronotypes add M. natalensis as a new host implicated in S. haematobium x S. bovis transmission. We discuss the origin of the new chronotypes which have become more complex with the appearance of several peaks in a 24-h day. We also discuss how the new populations of offspring may optimize intra-host ecological niche, host spectrum, and transmission time period.

scholarly journals Simulation of population dynamics of Bulinus globosus: Effects of environmental temperature on production of Schistosoma haematobium cercariae

2018 ◽  
Vol 12 (8) ◽  
pp. e0006651 ◽  
Author(s):  
Chester Kalinda ◽  
Moses J. Chimbari ◽  
William E. Grant ◽  
Hsiao-Hsuan Wang ◽  
Julius N. Odhiambo ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Schistosoma Haematobium ◽  
Environmental Temperature ◽  
Bulinus Globosus

scholarly journals Schistosoma haematobiumin Lake Malaŵi: susceptibility and molecular diversity of the snail hostsBulinus globosusandB. nyassanus

2008 ◽  
Vol 82 (4) ◽  
pp. 377-382 ◽  
Author(s):  
J.R. Stauffer ◽  
H. Madsen ◽  
B. Webster ◽  
K. Black ◽  
D. Rollinson ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Causative Agent ◽  
Schistosoma Haematobium ◽  
Species Complex ◽  
Molecular Diversity ◽  
Lake Malawi ◽  
Intermediate Hosts ◽  
Urinary Schistosomiasis ◽  
Bulinus Globosus ◽  
Mitochondrial Sequences

AbstractIntermediate hosts ofSchistosoma haematobium, the causative agent of urinary schistosomiasis, in Lake Malaŵi include:Bulinus globosus, a member of theB. africanusgroup andB. nyassanus, a diploid member of theB. truncatus/tropicusspecies complex. We compared genetic variability between isolates ofS. haematobiumfrom the southern part of the lake (Cape Maclear), where bothB. globosusandB. nyassanusplay a role as intermediate hosts, and isolates from the northern part, where onlyB. globosusis host. Data show that theS. haematobiumisolates from these two areas of Lake Malaŵi cannot be distinguished using nuclear or mitochondrial sequences and are capable of cross-infections.

Factors affecting the intensity of reinfection with Schistosoma haematobium following treatment with praziquantel

Parasitology ◽  
1991 ◽  
Vol 102 (1) ◽  
pp. 73-83 ◽  
Author(s):  
S. K. Chandiwana ◽  
M. E. J. Woolhouse ◽  
M. Bradley
Keyword(s):  
Rural Community ◽  
Schistosoma Haematobium ◽  
Time Of Day ◽  
Reinfection Rate ◽  
Water Contact ◽  
Factors Affecting ◽  
Quantitative Estimates ◽  
Index Of Exposure ◽  
Bulinus Globosus ◽  
Independent Effects

SUMMARYInfection with Schistosoma haematobium was studied in a rural community of approximately 500 persons in eastern Zimbabwe. The overall prevalence of infection, as determined by urine egg counts, was 40·1%, and of heavy infections (≥ 50 eggs/10 ml urine) was 11·0%. The prevalence of both heavy and all infections was highest in the 8 to 10-year-old age class. During 1987–88 data were obtained from 102 individuals on intensity of reinfection 14 weeks after treatment with praziquantel, the efficacy of treatment having been determined after 4 weeks. The water contact made by these individuals during 2-week periods immediately following treatment was recorded. The relative abundance of patent infected intermediate host snails, Bulinus globosus, was also monitored. An index of exposure was developed which weighted each water contact by its duration, the type of activity, the time of day, and the abundance of infected snails at the site used. The relationships between rates of reinfection, rates of exposure, and age were examined. Although only 13 individuals showed positive rates of reinfection, there were statistically significant and independent effects of both exposure and age on reinfection rate. Quantitative estimates of reinfection rates suggested that individuals aged 12 years or less acquired substantially more infection (measured as egg output) than individuals more than 12 years old.

Investigation into the prevalence of urinary schistosomiasis in the Agulu Lake area of Anambra State, Nigeria

1994 ◽  
Vol 68 (2) ◽  
pp. 119-123 ◽  
Author(s):  
A.C. Emejulu ◽  
F.F. Alabaronye ◽  
H.M.G. Ezenwaji ◽  
F.C. Okafor
Keyword(s):  
Schistosoma Haematobium ◽  
Lake Area ◽  
Host Age ◽  
Prevalence Rates ◽  
Intensity Of Infection ◽  
Urinary Schistosomiasis ◽  
Anambra State ◽  
Epidemiological Surveys ◽  
Significant Difference ◽  
Bulinus Globosus

AbstractIn epidemiological surveys for urinary schistosomiasis caused by Schistosoma haematobium in communities around Agulu Lake, Anambra State, Nigeria, between 1990 and 1992, the infection was found to be endemic in the area, especially in three towns: Nri, Agulu, and Adazi Nnukwu. The prevalence rates varied between these communities and with the year. Inter-town prevalence rates ranged from 5.96% to 54.00%. Intravillage prevalence rates ranged between 5.50% to 96.43%. Prevalence rates were highest in villages very close to Agulu lake. There was no significant difference in prevalence between the schools. Host age, but not sex, was found to play a significant role in prevalence and intensity of infection. There was also a strong correlation between visible haematuria and egg count per 10 ml urine, but eggs could be isolated in urine samples of different shades of coloration. Analysis of incidence of infection in these communities shows that Schistosoma haematobium incidence is high in Nri (55.17%) and low at Adazi Nnukwu (5.26%). Both Bulinus globosus and B. truncatus were found in the lake and both shed mammalian bifid schistosome cercariae.

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

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Masceline Jenipher Mutsaka-Makuvaza ◽  
Xiao-Nong Zhou ◽  
Cremance Tshuma ◽  
Eniola Abe ◽  
Justen Manasa ◽  
...  
Keyword(s):  
Schistosoma Haematobium ◽  
Geographical Area ◽  
Endemic Region ◽  
Urogenital Schistosomiasis ◽  
Water Contact ◽  
Additional Information ◽  
Bulinus Globosus ◽  
Species Groups ◽  
One Year ◽  
Low Prevalence

Abstract Background 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. 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. Results 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. Conclusions 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.

The effect of light and darkness on the production of cercariae of Schistosoma haematobium from Bulinus globosus

1987 ◽  
Vol 61 (4) ◽  
pp. 291-296 ◽  
Author(s):  
K. M. Raymond ◽  
A. J. Probert
Keyword(s):  
Schistosoma Haematobium ◽  
Continuous Illumination ◽  
Light Conditions ◽  
Dark Treatment ◽  
Bulinus Globosus ◽  
Normal Light ◽  
Peak Emission ◽  
Evening Peak ◽  
Second Peak ◽  
Effect Of Light

ABSTRACTThe cercariae of Schistosoma haematobium showed a diurnal periodicity of emergence from Bulinus globosus in a twelve hour light/dark cycle. Peak emission occurred at 11.00 hrs with a smaller peak at 20.00 hrs, following the start of the period of darkness. In continuous illumination this second peak was not seen, indicating that only the morning peak is circadian in origin. The evening peak occurs in response to dark treatment and can be produced by periods of darkness ranging from eight seconds to one hour. The longer the period of dark treatment the longer the rise in output is maintained on return to light conditions. Subjection of snails to periods of dark treatment during the normal light period caused a reduction in the evening peak with the largest effect seen following the longest period of darkness. An increased output of cercariae was seen following fifteen minutes exposure to a range of light intensities, the largest increase occurring at 10 000 and 7000 lux and complete darkness. The rapidity of this reaction to variations in light intensity suggests that the cercariae of S. haematobium are showing emergence in response to shadows.

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