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Journal of Korean Medical Science Aug 2018which causes urogenital schistosomiasis (UGS) is highly prevalent in African countries. Urine microscopy (UM) is the first-line diagnostic method of UGS. Enzyme-linked...
BACKGROUND
which causes urogenital schistosomiasis (UGS) is highly prevalent in African countries. Urine microscopy (UM) is the first-line diagnostic method of UGS. Enzyme-linked immunosorbent assay (ELISA) is a common method for screening many parasite infections primarily or alternatively. The present study established an in-house diagnostic system by ELISA and evaluated its diagnostic efficacy in comparison with UM for screening UGS in White Nile State, Republic of Sudan, 2011-2013.
METHODS
A total of 490 participants were screened by UM or ELISA, and 149 by both. The in-house ELISA system was established employing soluble egg antigen of and the cut-off absorbance was set at 0.270.
RESULTS
Of the 149 subjects, 58 participants (38.9%) were positive by UM, 119 (79.9%) were positive by ELISA and 82 (55.0%) showed consistently positive or negative results by both methods. The diagnostic sensitivity of ELISA was 94.8% and specificity was 29.7% based on UM results. The ELISA positive serum samples also cross-reacted with egg antigens of and .
CONCLUSION
We have established in-house ELISA for screening serum immunoglobulin (Ig) G antibodies by employing soluble egg antigen of for diagnosis of UGS with 94.8% sensitivity and 29.7% specificity. The ELISA system can supplement the conventional diagnosis by UM.
Topics: Adolescent; Animals; Antigens, Helminth; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Microscopy; Schistosoma haematobium; Schistosomiasis haematobia; Schistosomiasis mansoni; Urinalysis
PubMed: 30093850
DOI: 10.3346/jkms.2018.33.e238 -
International Journal of Molecular... Jul 2015The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma...
The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1) gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct) values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01). In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays.
Topics: Animals; DNA Primers; Nucleic Acid Denaturation; Real-Time Polymerase Chain Reaction; Schistosoma haematobium; Schistosoma mansoni; Schistosomiasis; Sensitivity and Specificity; Temperature
PubMed: 26193254
DOI: 10.3390/ijms160716085 -
Break Out: urogenital schistosomiasis and Schistosoma haematobium infection in the post-genomic era.PLoS Neglected Tropical Diseases 2013
Topics: Africa; Animals; Anthelmintics; Genome, Helminth; Humans; Praziquantel; Schistosoma haematobium; Schistosomiasis haematobia
PubMed: 23556007
DOI: 10.1371/journal.pntd.0001961 -
PLoS Neglected Tropical Diseases Sep 2017Large-scale schistosomiasis control programs are implemented in regions with diverse social and economic environments. A key epidemiological feature of schistosomiasis...
BACKGROUND
Large-scale schistosomiasis control programs are implemented in regions with diverse social and economic environments. A key epidemiological feature of schistosomiasis is its small-scale heterogeneity. Locally profiling disease dynamics including risk factors associated with its transmission is essential for designing appropriate control programs. To determine spatial distribution of schistosomiasis and its drivers, we examined schoolchildren in Kwale, Kenya.
METHODOLOGY/PRINCIPAL FINDINGS
We conducted a cross-sectional study of 368 schoolchildren from six primary schools. Soil-transmitted helminths and Schistosoma mansoni eggs in stool were evaluated by the Kato-Katz method. We measured the intensity of Schistosoma haematobium infection by urine filtration. The geometrical mean intensity of S. haematobium was 3.1 eggs/10 ml urine (school range, 1.4-9.2). The hookworm geometric mean intensity was 3.2 eggs/g feces (school range, 0-17.4). Heterogeneity in the intensity of S. haematobium and hookworm infections was evident in the study area. To identify factors associated with the intensity of helminth infections, we utilized negative binomial generalized linear mixed models. The intensity of S. haematobium infection was associated with religion and socioeconomic status (SES), while that of hookworm infection was related to SES, sex, distance to river and history of anthelmintic treatment.
CONCLUSIONS/SIGNIFICANCE
Both S. haematobium and hookworm infections showed micro-geographical heterogeneities in this Kwale community. To confirm and explain our observation of high S. haematobium risk among Muslims, further extensive investigations are necessary. The observed small scale clustering of the S. haematobium and hookworm infections might imply less uniform strategies even at finer scale for efficient utilization of limited resources.
Topics: Adolescent; Ancylostomatoidea; Animals; Child; Cross-Sectional Studies; Demography; Feces; Female; Hookworm Infections; Humans; Islam; Kenya; Linear Models; Male; Parasite Egg Count; Risk Factors; Schistosoma haematobium; Schistosomiasis haematobia; Schools; Social Class; Soil; Students
PubMed: 28863133
DOI: 10.1371/journal.pntd.0005872 -
BMC Public Health Oct 2020Individuals living in Schistosoma haematobium endemic areas are often at risk of having other communicable diseases simultaneously. This usually creates diagnostic...
BACKGROUND
Individuals living in Schistosoma haematobium endemic areas are often at risk of having other communicable diseases simultaneously. This usually creates diagnostic difficulties leading to misdiagnosis and overlooking of schistosomiasis infection. In this study we investigated the prevalence and severity of coinfections in pre-school age children and further investigated associations between S. haematobium prevalence and under 5 mortality.
METHODS
A community based cross-sectional survey was conducted in Shamva District, Zimbabwe. Using random selection, 465 preschool age children (1-5 years of age) were enrolled through clinical examination by two independent clinicians for the following top morbidity causing conditions: respiratory tract infections, dermatophytosis, malaria and fever of unknown origin. The conditions and their severe sequels were diagnosed as per approved WHO standards. S. haematobium infection was diagnosed by urine filtration and the children were screened for conditions common in the study area which included HIV, tuberculosis, malnutrition and typhoid. Data was analysed using univariate and multinomial regression analysis and relative risk (RR) calculated.
RESULTS
Prevalence of S. haematobium was 35% (145). The clinical conditions assessed had the following prevalence in the study population: upper respiratory tract infection 40% (229), fever of unknown origin 45% (189), dermatophytosis 18% and malaria 18% (75). The odds of co-infections observed with S. haematobium infection were: upper respiratory tract infection aOR = 1.22 (95% CI 0.80 to 1.87), dermatophytosis aOR = 4.79 (95% CI 2.78 to 8.25), fever of unknown origin aOR = 10.63 (95% CI 6.48-17.45) and malaria aOR = 0.91 (95% CI 0.51 to1.58). Effect of schistosomiasis coinfection on disease progression based on the odds of the diseases progressing to severe sequalae were: Severe pneumonia aOR = 8.41 (95% CI 3.09-22.93), p < 0.0001, complicated malaria aOR = 7.09 (95% CI 1.51-33.39), p = 0.02, severe dermatophytosis aOR = 20.3 (95% CI 4.78-83.20):p = 0.03, and fever of unknown origin aOR = 1.62 (95%CI 1.56-4.73), p = 0.02.
CONCLUSION
This study revealed an association between schistosomiasis and the comorbidity conditions of URTI, dermatophytosis, malaria and FUO in PSAC living in a schistosomiasis endemic area. A possible detrimental effect where coinfection led to severe sequels of the comorbidity conditions was demonstrated. Appropriate clinical diagnostic methods are required to identify associated infectious diseases and initiate early treatment of schistosomiasis and co-infections in PSAC.
Topics: Animals; Child; Child, Preschool; Coinfection; Cross-Sectional Studies; Humans; Infant; Prevalence; Schistosoma haematobium; Schistosomiasis haematobia; Zimbabwe
PubMed: 33076903
DOI: 10.1186/s12889-020-09634-0 -
Antimicrobial Agents and Chemotherapy Aug 2018There is a growing consensus to include preschool-aged children in preventive chemotherapy programs with praziquantel to improve schistosomiasis control. However,...
There is a growing consensus to include preschool-aged children in preventive chemotherapy programs with praziquantel to improve schistosomiasis control. However, pharmacokinetic data, crucial to establish a safe and effective dose for this age group, are sparse. The objective of this study was to establish and compare the pharmacokinetic parameters of praziquantel in preschool- and school-aged children with schistosomiasis. Two pharmacokinetic trials in school- and preschool-aged children infected with or were conducted in Côte d'Ivoire. Dried blood spot samples were taken from 492 children at 10 time points following a single oral dose of 20, 40, or 60 mg/kg of body weight of praziquantel and analyzed using liquid chromatography-mass spectrometry. Noncompartmental analysis (NCA) was performed to obtain the pharmacokinetic parameters of -praziquantel (RPZQ), -praziquantel (SPZQ), and -4-hydroxy-praziquantel. No significant differences in pharmacokinetic parameters between species-specific infections were observed. While pharmacokinetic parameters differed significantly between age groups for , this trend was not observed with Neither the area under the curve (AUC) nor the maximal blood concentration () presented clear dose proportionality for R- and SPZQ. Logistic regression indicated a relationship between the RPZQ AUC and and the probability of cure. Praziquantel is subject to complex metabolic processes following erratic absorption. While the results of NCA are a very informative base for a better understanding of the drug, a more targeted approach in the form of population modeling is needed to quantify the factors influencing metabolic processes and draw conclusions.
Topics: Adolescent; Animals; Child; Child, Preschool; Chromatography, Liquid; Humans; Praziquantel; Schistosoma haematobium; Schistosoma mansoni; Schistosomiasis mansoni; Tandem Mass Spectrometry
PubMed: 29866859
DOI: 10.1128/AAC.02253-17 -
International Journal of Environmental... Jan 2022The epidemiology of schistosomiasis transmission varies depending on the circumstances of the surrounding water bodies and human behaviors. We aimed to explore cercarial...
BACKGROUND
The epidemiology of schistosomiasis transmission varies depending on the circumstances of the surrounding water bodies and human behaviors. We aimed to explore cercarial emergence patterns from snails that are naturally affected by human schistosomiasis and non-human trematodes. In addition, this study aimed to explore how schistosomiasis infection affects snail survival, reproduction, and growth.
METHODS
We measured the survival rate, fecundity, and size of snails and the cercarial rhythmicity of and . The number of egg masses, eggs per egg mass, and snail deaths were counted for 7 weeks. The survival rate and cumulative hazard were assessed for infected and non-infected snails.
RESULTS
and cercariae peaked at 9:00-11:00 a.m. Infection significantly reduced the survival rate of , which was 35% and 51% for infected and non-infected snails, respectively ( = 0.02), at 7 weeks after infection. The hazard ratio of death for infected snails compared to non-infected snails was 1.65 (95% confidence interval: 1.35-1.99; = 0.01).
CONCLUSIONS
An understanding of the dynamics of schistosomiasis transmission will be helpful for formulating schistosomiasis control and elimination strategies. Cercarial rhythmicity can be reflected in health education, and the reproduction and survival rate of infected snails can be used as parameters for developing disease modeling.
Topics: Animals; Biomphalaria; Parasites; Rivers; Schistosoma haematobium; Schistosoma mansoni; Sudan
PubMed: 35162527
DOI: 10.3390/ijerph19031508 -
The Korean Journal of Parasitology Feb 2015Schistosoma haematobium is one of the most prevalent parasitic flatworms, infecting over 112 million people in Africa. However, little is known about the genetic...
Schistosoma haematobium is one of the most prevalent parasitic flatworms, infecting over 112 million people in Africa. However, little is known about the genetic diversity of natural S. haematobium populations from the human host because of the inaccessible location of adult worms in the host. We used 4 microsatellite loci to genotype individually pooled S. haematobium eggs directly from each patient sampled at 4 endemic locations in Africa. We found that the average allele number of individuals from Mali was significantly higher than that from Nigeria. In addition, no significant difference in allelic composition was detected among the populations within Nigeria; however, the allelic composition was significantly different between Mali and Nigeria populations. This study demonstrated a high level of genetic variability of S. haematobium in the populations from Mali and Nigeria, the 2 major African endemic countries, suggesting that geographical population differentiation may occur in the regions.
Topics: Adolescent; Animals; Child; Female; Genetic Variation; Genotype; Humans; Male; Mali; Microsatellite Repeats; Nigeria; Schistosoma haematobium; Schistosomiasis haematobia
PubMed: 25748721
DOI: 10.3347/kjp.2015.53.1.129 -
Journal of Clinical Microbiology May 2018
Topics: Acquired Immunodeficiency Syndrome; Animals; Hematuria; Male; Schistosoma haematobium; Schistosomiasis haematobia
PubMed: 29695541
DOI: 10.1128/JCM.00737-16 -
PLoS Neglected Tropical Diseases Aug 2021Prompt diagnosis of acute schistosomiasis benefits the individual and provides opportunities for early public health intervention. In endemic areas schistosomiasis is...
INTRODUCTION
Prompt diagnosis of acute schistosomiasis benefits the individual and provides opportunities for early public health intervention. In endemic areas schistosomiasis is usually contracted during the first 5 years of life, thus it is critical to look at how the infection manifests in this age group. The aim of this study was to describe the prodromal signs and symptoms of early schistosomiasis infection, correlate these with early disease progression and risk score to develop an easy to use clinical algorithm to identify early Schistosoma haematobium infection cases in resource limited settings.
METHODOLOGY
Two hundred and four, preschool age children who were lifelong residence of a schistosomiasis endemic district and at high risk of acquiring schistosomiasis were followed up from July 2019 to December 2019, during high transmission season. The children received interval and standard full clinical evaluations and laboratory investigations for schistosomiasis by clinicians blinded from their schistosomiasis infection status. Diagnosis of S. haematobium was by urine filtration collected over three consecutive days. Signs and symptoms of schistosomiasis at first examination visit were compared to follow-up visits. Signs and symptoms common on the last schistosomiasis negative visit (before a subsequent positive) were assigned as early schistosomiasis infection (ESI), after possible alternative causes were ruled out. Logistic regression identified clinical predictors. A model based score was assigned to each predictor to create a risk for every child. An algorithm was created based on the predictor risk scores and validated on a separate cohort of 537 preschool age children.
RESULTS
Twenty-one percent (42) of the participants were negative for S. haematobium infection at baseline but turned positive at follow-up. The ESI participants at the preceding S. haematobium negative visit had the following prodromal signs and symptoms in comparison to non-ESI participants; pruritic rash adjusted odds ratio (AOR) = 21.52 (95% CI 6.38-72.66), fever AOR = 82 (95% CI 10.98-612), abdominal pain AOR = 2.6 (95% CI 1.25-5.43), pallor AOR = 4 (95% CI 1.44-11.12) and a history of facial/body swelling within the previous month AOR = 7.31 (95% CI 3.49-15.33). Furthermore 16% of the ESI group had mild normocytic anaemia, whilst 2% had moderate normocytic anaemia. A risk score model was created using a rounded integer from the relative risks ratios. The diagnostic algorithm created had a sensitivity of 81% and a specificity of 96.9%, Positive predictive value = 87.2% and NPV was 95.2%. The area under the curve for the algorithm was 0.93 (0.90-0.97) in comparison with the urine dipstick AUC = 0.58 (0.48-0.69). There was a similar appearance in the validation cohort as in the derivative cohort.
CONCLUSION
This study demonstrates for the first time prodromal signs and symptoms associated with early S. haematobium infection in pre-school age children. These prodromal signs and symptoms pave way for early intervention and management, thus decreasing the harm of late diagnosis. Our algorithm has the potential to assist in risk-stratifying pre-school age children for early S. haematobium infection. Independent validation of the algorithm on another cohort is needed to assess the utility further.
Topics: Algorithms; Anemia; Animals; Child, Preschool; Cross-Sectional Studies; Female; Humans; Logistic Models; Male; Prevalence; Prodromal Symptoms; Risk Factors; Rural Population; Schistosoma haematobium; Schistosomiasis haematobia; Zimbabwe
PubMed: 34339415
DOI: 10.1371/journal.pntd.0009599