Schistosomiasis Endemic Areas Research Articles

Application of a Genus-Specific LAMP Assay for Schistosome Species to Detect Schistosoma haematobium x Schistosoma bovis Hybrids.

Schistosomiasis is a disease of great medical and veterinary importance in tropical and subtropical regions caused by different species of parasitic flatworms of the genus Schistosoma. The emergence of natural hybrids of schistosomes indicate the risk of possible infection to humans and their zoonotic potential, specifically for Schistosoma haematobium and S. bovis. Hybrid schistosomes have the potential to replace existing species, generate new resistances, pathologies and extending host ranges. Hybrids may also confuse the serological, molecular and parasitological diagnosis. Currently, LAMP technology based on detection of nucleic acids is used for detection of many agents, including schistosomes. Here, we evaluate our previously developed species-specific LAMP assays for S. haematobium, S. mansoni, S. bovis and also the genus-specific LAMP for the simultaneous detection of several Schistosoma species against both DNA from pure and, for the first time, S. haematobium x S. bovis hybrids. Proper operation was evaluated with DNA from hybrid schistosomes and with human urine samples artificially contaminated with parasites’ DNA. LAMP was performed with and without prior DNA extraction. The genus-specific LAMP properly amplified pure Schistosoma species and different S. haematobium-S. bovis hybrids with different sensitivity. The Schistosoma spp.-LAMP method is potentially adaptable for field diagnosis and disease surveillance in schistosomiasis endemic areas where human infections by schistosome hybrids are increasingly common.

Schistosoma mansoni Heterochromatin Protein 1 (HP1) nuclear interactome in cercariae

Schistosoma mansoni causes schistosomiasis, which affects 240 million people, and 700 million people are living at risk of infection. Epigenetic mechanisms are important for transcriptional control and are well-known conserved transcriptional co-regulators in evolution, already described in mammal, yeast, protozoa and S. mansoni, responsible for heterochromatization and gene silence mechanisms through the formation of complexes of transcriptional repression in chromatin. Previous results from another group have shown that HP1 (SmCBX) proteins form chromatin complexes with SmMDB2/3 proteins and regulate stem cells and oviposition in parasite adult worms. In addition, results from other groups have shown that cercariae are transcriptionally silent and epigenetic mechanisms are involved in the regulation of gene expression in this stage. In this work, our aim was to give insights into SmHP1 and proteins involved in transcriptional regulation in the cercariae stage. Using monoclonal anti-HP1 antibody for Western blotting, immunoprecipitation, and mass spectrometry, we preliminarily determined nuclear proteins that putatively interact with HP1 to form complexes to regulate gene expression, heterochromatin formation, and translational complexes in the cercariae stage. So far, our data is to give some insights into nuclear interactors in S. mansoni cercariae. SignificanceThe significance of this original paper is the evidence for Heterochromatin Protein (HP1), interaction with nuclear proteins in the cercariae stage. Schistosoma mansoni cercariae are the infective stage of the human beings in endemic areas of schistosomiasis, a neglected disease, most prevalent in Brazil and Africa. While cercariae are waiting for a host, it does not feed, gene expression is silent and protein synthesis is stopped. These biochemical mechanisms are recovered when cercariae find a human host, but all proteins and mechanisms are not still elucidated. Until now, literature shows that these phenomena are regulated by epigenetics mechanisms, dependent of histone posttranslational modifications. But we have few pieces of evidence about the other proteins that participates in these processes and which are the co-regulators of expression.

Impact of Coinfection with Schistosoma mansoni on the Antibody Response to Helicobacter pylori.

In many tropical areas, the coinfection of Schistosoma spp. and other pathogens is frequent. The impact of schistosomiasis on other infections has been demonstrated for several organisms. Infection with the widely spread bacterium, Helicobacter pylori, has been linked to ulcers and tumors of the digestive system with the humoral immune response playing possible modulatory roles. The present study investigated the impact of patent S. mansoni infection on the antibody response to H. pylori. A total of 100 participants from a schistosomiasis endemic area in Egypt were enrolled in the study. Based on the detection of S. mansoni eggs and H. pylori coproantigen in fecal samples, they were equally divided into four groups: schistosomiasis, concomitant S. mansoni and H. pylori infection, H. pylori infection alone, and healthy controls. Anti-H. pylori IgG and IgA were determined in serum samples using ELISA. A significantly lower IgA seropositivity rate and significantly lower IgG levels were found in patients with concomitant schistosomiasis (Gp2) compared to those infected only with H. pylori (Gp1). Concomitant S. mansoni infection with light to moderate intensity alters serological responses to H. pylori. In schistosomiasis endemic areas, the routine examination for H. pylori infection should, therefore, rely on coproantigen level rather than antibody levels. Further studies should investigate histopathological changes and other immunological parameters in coinfection.

A systematic review of handheld tools in lieu of colposcopy for cervical neoplasia and female genital schistosomiasis.

BackgroundVisualization of the lesions in the lower genital tract is the mainstay for diagnosis of the four lesions found in female genital schistosomiasis (FGS), but colposcopes are generally not available in low‐resource settings.ObjectiveWe sought to review handheld devices that could potentially be used for FGS diagnosis.Search strategyWe searched Medline and Embase 2015–2019 for handheld devices used in cervical cancer screening and FGS diagnosis.Selection criteriaWe excluded studies that did not compare the device to standard‐of‐care colposcopes or histopathology.Main results and conclusionIn 11 studies, four handheld colposcopes, two smartphones, and one compact digital camera were evaluated. Two handheld colposcopes were found to be potentially adequate for FGS diagnosis, namely Gynocular and Mobile ODT. The smartphones and digital camera did not have sufficient magnification to diagnose grainy sandy patches, one of the FGS lesion types. Customized software should be made to support the diagnosis of both FGS and cervical neoplasia. Real‐time postgraduate training and quality control should be considered in future studies of handheld colposcopes. For patients from schistosomiasis endemic areas, we recommend that handheld devices are used for FGS. Studies are needed to determine which of the two devices is most adequate for FGS diagnosis in schistosomiasis endemic areas.

Rapid Assessment on Potential Risks of Schistosomiasis Transmission - 7 PLADs, China, 2019 and 2021.

What is already known about this topic?Oncomelania hupensis(O. hupensis) and livestock are main infection sources of schistosomiasis. The schistosome infected O. hupensis and livestock’s feces are important risk factors in the transmission of schistosomiasis. What is added by this report?The potential risks of schistosomiasis transmission remain prevalent, giving an early warning to local government with information on existing transmission risks. It is expected that the effectiveness and efficiency of schistosomiasis surveillance could be improved by conducting rapid risk assessment at the beginning of transmission season.What are the implications for public health practice?Rapid risk assessment is essential in early detection and the active monitoring of indicators of the transmission risks of schistosomiasis in endemic areas. This could work synergistically with surveillance system to minimize infections and prevent rebounds of endemic schistosomiasis outbreaks.

Assessment of the Transmission Risk of Schistosomiasis after Flooding — North Poyang Lake, Jiangxi Province, China, 2020

What is already known about this topic? Over 90% of Oncomelania snails, the only intermediate host of Schistosoma japonicum, are distributed in the middle and low reaches of Yangtze River. Flooding can extend the distribution of Oncomelania snails and hence accelerate the transmission of schistosomiasis. What is added by this report? Although the dispersal of Oncomelania snails was negligible in north Poyang Lake after flooding in 2020, 2 samples of cattle feces with Schistosoma egg and 2 infected snails samples were indeed found. All four risk sites were distributed in Lushan County. Cattle feces were observed in the six out of seven field sites in Lushan County. What are the implications for public health practice? The present national control strategy focusing on control of infection source should be reinforced in Lushan and other schistosomiasis endemic areas. Overlaps of infected snails and cattle feces with Schistosoma egg were not observed, which called for intensive surveillance in Lushan County.

Reappearance of Risk of Schistosomiasis Transmission and the Response After 27 Years of Interrupted Transmission - Guangdong Province, China, 2019.

What is already known about this topic?No live specimens of the snail Oncomelania hupensis (O. hupensis) and indigenous infected cases of schistosomiasis japonicum have been found in Guangdong Province since 1993, but live O. hupensis was found again in 2019. This study conducted O. hupensis identification and elimination. What is added by this report?In 2019, live O. hupensis specimens were detected by routine surveillance in areas in Qujiang of Shaoguan City and Yingde of Qingyuan City, and an emergency response was launched immediately. What are the implications for public health practice?The suspected habitat of O. hupensis in originally endemic areas of schistosomiasis in Guangdong is still complicated, so it is necessary to record suspected habitats comprehensively and carry out scientific routine surveillance for O. hupensis.

Schistosomiasis Associated Glomerulopathy (Glomerulonephristis / Nephrotic Syndrome): A review and Update of the Literature

Schistosomiasis may affect a number of organs within the human body. Schistosomiasis may also be associated with glomerular disease of the kidney in the form of glomerulonephritis and nephrotic syndrome. The association between Schistosomiasis and glomerulopathy may not be well known by a number of practitioners and its pathophysiology may not be very well understood and this could be due to the underdiagnosis of the disease due to the possibility of lack of facilities within the Schistosomiasis endemic areas of the world especially within tropical Africa. Nevertheless, there are a number of patterns of renal involvement in Schistosomiasis which include (a) upper urinary tract sequelae of lower urinary tract Schistosomiasis pathology, (b) immune-related glomerulonephritis, (c) as well as oxidant-stress-mediated renal tubular glomerulonephritis. The renal involvement by Schistosomiasis does tend to be ensued by the development of Schistosomiasis-associated Glomerulopathy (Glomerulonephritis / Nephrotic Syndrome) of varying severity. Individuals affected by Schistosomiasis-associated kidney disease may develop (a) asymptomatic disease which tends to related to self-limited and asymptomatic glomerular disease (b) symptomatic disease which most commonly would tend to present with nephrotic syndrome most often in patients who develop hepato-splenic schistosomiasis with liver fibrosis associated with Schistosoma mansoni infection. Symptomatic patients tend to develop severe hypo-proteinemia, half of the patients tend to have elevated blood pressure. In the absence of nephrotic syndrome, patients who have Schistosomiasis-associated glomerulopathy may manifest with: (a) isolated non-nephrotic syndrome proteinuria (b) acute glomerulonephritis associated with haematuria and heavy proteinuria, (c) Nephrotic syndrome together with systemic manifestations of co-infection with salmonella (class II) or hepatitis C virus (Class I), (d) End stage renal disease (ESRD). Some of the patients who have Schistosomiasis of the kidney may present with Haematuria, Hypertension, Hepato-splenic Schistosomiasis. The diagnosis should be suspected with regard to the following scenarios: (a) clinical suspicion in a patient with kidney disease who is known or has been known to have Schistosoma mansoni; (b) exposure to an endemic area, (c) clinical evidence / demonstration of chronic hepatosplenic schistosomiasis, (d) if the patient has not been diagnosed as having been afflicted with schistosomiasis, then schistosomal infection should be documented, (e) majority of patients with schistosomiasis and kidney disease should have kidney biopsy. (f) The patients should be evaluated for co-infection with salmonella, hepatitis C virus, and hepatitis B virus in order to ensure adequate treatment of the disease. Schistosomiasis is the second most devastating tropical parasitic disease globally which tends to be responsible for many urological complications. Nevertheless, glomerular injury is an uncommon complication which has mainly or most often described with Schistosoma Mansoni. When patients who have Schistosomiasis-associated Kidney disease are managed and followed-up on long-term basis with renal end points, one third of the patients independent of the histopathology examination features of the kidney biopsies would tend to progress dialysis. Membranoproliferative glomerulonephritis (MPGN) is an uncommon complication associated with Schistosoma Haematobium infection which tends to be associated with potentially poor prognosis. MPGN could lead quickly to End Stage Renal Disease (ESRD). Anti-helminthic and immunosuppressive medicaments tend not to be effective at advanced stages of the disease and hence efforts need to be focused upon the prevention, early detection, as well as treatment of Schistosoma infections among at-risk groups of individuals. In order to reduce morbidity related to Schistosoma-associated nephropathy, public health policy, should be concentrated upon the prevention of the disease by the control of snail, improved sanitation, and health education, as well as by the implementation, and sustenance of chemotherapy-based control strategies. Considering that many individuals are found yearly to be inflicted by Schistosomiasis who tend to dwell in more rural parts of their countries where facilities for the undertaking of renal function tests and biopsies of the kidney tend not to be readily available, there is the likelihood that Schistosomiasis-associated nephropathies may be highly underdiagnosed globally.

Endemic status of schistosomiasis in People's Republic of China in 2019

This report presented the endemic status of schistosomiasis in the People's Republic of China at a national level in 2019, and analyzed the data collected from the national schistosomiasis prevention and control system and 455 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) endemic for schistosomiasis in China, Shanghai, Zhejiang, Fujian, Guangdong and Guangxi continued to consolidate the achievements of schistosomiasis elimination, Sichuan Province achieved transmission interruption, Jiangsu newly achieved the standard of transmission interruption and 5 provinces of Yunnan, Hubei, Anhui, Jiangxi and Hunan maintained transmission control by the end of 2019. There were 450 endemic counties (cities, districts) endemic for schistosomiasis, including 28 500 endemic villages covering 70 667 800 people at risk of infections. Among the 450 endemic counties (citis, districts), 66.89% (301/450), 28.44% (128/450) and 4.67% (21/450) kept the criteria of elimination, transmission interruption and transmission control of schistosomiasis, respectively. By the end of 2019, a total of 30 170 advanced schistosomiasis cases were documented in China. In 2019, a total of 12 090 712 individuals received inquiry examinations and 1 740 764 were positive; 5 158 369 individuals received serological tests and 89 753 were seropositive. A total of 327 475 individuals received stool examinations and 5 were positive, including one case of acute schistosomiasis. In 2019, snail survey was performed in 19 726 endemic villages in China and Oncomelania snails were found in 7 322 villages, accounting for 37.12% of all surveyed villages, with 6 villages with emerging snail habitats. Snail survey covered an area of 585 286.24 hm2 and 174 270.42 hm2 snail habitats were found, including emerging snail habitats of 64.20 hm2; however, no infected snails were identified. In 2019, a total of 605 965 bovines were raised in the schistosomiasis endemic areas of China, and 183 313 received serological examinations, with 1 176 positives detected, while 134 978 bovines received stool examinations, with 7 positives identified. In 2019, there were 28 557 patients with schistosomiasis receiving praziquantel chemotherapy, and expanded chemotherapy was given to 1 008 083 person-times; there were 7 bovines with schistosomiasis receiving praziquantel chemotherapy, and 296 053 herd-times expanded chemotherapy was given to bovines. In 2019, snail habitats at an area of 128 754.26 hm2 were given chemical treatment, and the actual area of chemical treatment was 69 605.55 hm2, while environmental improvements were performed in snail habitats covering an area of 2 847.00 hm2. Data from the 455 national schistosomiasis surveillance sites of China showed that the mean Schistosoma japonicum infection rates were both zero in humans and bovines in 2019, and no infected snails were found. The results demonstrate that the overall endemic situation of schistosomiasis remains at a lower infection level in China; however, there is still a risk of schistosomiasis transmission. To achieve the target set in the National Thirteenth Five-Year Plan for Schistosomiasis Control and consolidate the achievements of schistosomiasis control, precision control on schistosomiasis still needs to be reinforced in China.

Association of Schistosoma haematobium infection morbidity and severity on co-infections in pre-school age children living in a rural endemic area in Zimbabwe

BackgroundIndividuals 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.MethodsA 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.ResultsPrevalence 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.ConclusionThis 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.

Anthelminthic treatment receipt and its predictors in Lake Victoria fishing communities, Uganda: Intervention coverage results from the LaVIISWA cluster randomised trial.

BackgroundMass drug administration (MDA) is a cornerstone of control of parasitic helminths. In schistosomiasis-endemic areas with >50% of school-aged children infected, community-wide MDA with praziquantel is recommended by the World Health Organisation (WHO), with target coverage of >75%. Using data from a cluster-randomised trial of MDA treatment strategies, we aimed to describe the proportion of eligible residents who received MDA and predictors of treatment receipt, and to assess associations with helminth prevalence.MethodsIn the Koome islands of Lake Victoria, Uganda, where baseline schistosomiasis prevalence (by single stool sample, Kato Katz) was 52% overall (all ages) and 67% among school-aged children, we conducted a cluster-randomised trial of community-wide, intensive MDA (quarterly single-dose praziquantel 40mg/kg; triple-dose albendazole 400mg) versus standard, Uganda government intervention (annual single-dose praziquantel 40mg/kg; 6-monthly single-dose albendazole). Twenty-six fishing villages were randomised, 13 per trial arm, for four years. At each treatment round, praziquantel treatment and the first dose of albendazole treatment were directly observed by the study team, registers of village residents were updated and the proportion receiving treatment among those eligible recorded.ResultsDuring the four-year MDA, at each treatment round an average of 13,382 people were registered in the 26 villages (7,153 and 6,229 in standard and intensive intervention villages, respectively). Overall, the proportion of those eligible receiving praziquantel was lower than for albendazole (60% versus 65%), particularly in the standard arm (61% versus 71%) compared to the intensive arm (60% versus 62%). Albendazole receipt was lower when given concurrently with praziquantel. Absence was the commonest reason for non-receipt of treatment (81% albendazole, 77% praziquantel), followed by refusal (14% albendazole, 18% praziquantel). Proportions receiving treatment were lowest among school-aged children, but did not differ by sex. Longitudinal analysis of a subgroup of residents who did not move during the study period found that persistent non-receipt of treatment in this subgroup was rare. Refusal to receive treatment was highest among adults and more common among females.ConclusionIn schistosomiasis high-risk communities, a combination of approaches to increasing treatment coverage, such as extended periods of treatment delivery, and the provision of incentives, may be required to achieve WHO targets.

Human water contact patterns in active schistosomiasis endemic areas.

One major risk factor common to individuals in schistosomiasis endemic areas is water contact patterns. Effort to determine the dynamics in water contact patterns in different regions needs utmost attention in order to suggest a better control strategy for schistosome infection. Quantitative observations on human water contact activities were recorded in Yewa North Local Government Area of Ogun State for a period of two years. Frequency and duration of observed water contact activities were recorded. Males had the highest water contact during the rainy season with 51.1% compared to females with 48.9%. Females had the highest water contact with 51.0% while males had 49.0% during the dry season. The age group 10-19 years had the highest water contact with 27.1%, this was followed by 20-29 years and 30-39 years age groups with 23.6% and 22.1%, respectively, during the rainy season. Our results showed that water contact activities differ with respect to different communities, sex and age groups. Previous high prevalence of schistosome infection in the study areas could be attributed to high water contact activities. Therefore, provision of adequate pipe-borne water, good sanitation and improved knowledge on schistosome life cycle among the community members will reduce the high rate of human water contacts.

Village Response to Mass Drug Administration for Schistosomiasis in Mwanza Region, Northwestern Tanzania: Are We Missing Socioeconomic, Cultural, and Political Dimensions?

.Praziquantel (PZQ)-based mass drug administration (MDA) is the main approach for controlling schistosomiasis in endemic areas. Interventions such as provision and use of clean and safe water, minimizing contacts with infested water, disposal of human waste in latrines, and snail control provide additional key interventions to break the transmission cycle and could complement and perhaps sustain the benefits of MDA. However, all interventions deployed need to be accepted by the targeted communities. A qualitative study was conducted to examine factors that might differentiate villages which did not show a substantial decrease in Schistosoma mansoni prevalence despite repeated, high treatment coverage referred to as “persistent hotspot (PHS) villages” from villages which showed a substantial decrease in prevalence referred to as “responding (RES) villages.” A convenient sample of adults was drawn from eight villages. Thirty-nine key informants were interviewed and 16 focus groups were held with a total of 123 participants. Data were analyzed manually using a thematic content approach. In both PHS and RES villages, schistosomiasis was not considered to be a priority health problem because of its chronic nature, lack of knowledge and awareness, and poverty among study communities. Persistent hotspot villages exhibited poor leadership style, lack of or insufficient social engagement, little or lack of genuine community participation, little motivation, and commitment to schistosomiasis control compared with RES villages where there were commitment and motivation to fight schistosomiasis. We support the view of scholars who advocate for the adoption of a biosocial approach for effective and sustainable PZQ-based MDA for schistosomiasis control.

Interleukin-10 and tumour necrosis factor alpha promoter region polymorphisms and susceptibility to urogenital schistosomiasis in young Zimbabwean children living in Schistosoma haematobium endemic regions.

BackgroundHost genetic factors can influence susceptibility, morbidity and mortality from schistosomiasis. The study explored the association between single nucleotide polymorphisms (SNPs) in interleukin-10 (IL-10) and tumour necrosis factor alpha (TNF-α) promoter regions and susceptibility to Schistosoma haematobium infection.MethodsUrine specimens were collected from 361 primary school children aged 5–15 years from schistosomiasis endemic areas of Manicaland and Mashonaland central provinces. Schistosoma haematobium was diagnosed using the urine filtration method. Only 272 participants provided adequate blood for genotyping. Genotyping was performed using the amplification refractory mutation system-polymerase chain reaction. The association between IL-10 and TNF-α SNPs and S. haematobium infection was analysed using the chi-square test.ResultsSchistosoma haematobium infection was confirmed in 26.8% of the participants. No significant difference in S. haematobium prevalence between men (51.6% of those infected) and women (48.4%) (χ2 = 0.008, df = 1, p = 0.928) was observed. The total IL-10 -1082 G, IL-10 -819 C and TNF-α -308G allele distribution between S. haematobium infected and uninfected participants was 50.7% and 51.5% (χ2 = 0.025, df = 1, p = 0.87), 54.3% and 60.6% (χ2 = 1.187, df = 1, p = 0.187) and 82.1% and 80.9% (χ2 = 0.099, df = 1, p = 0.753), respectively, and the differences were not significant.ConclusionInterleukin-10 -1082 G/A, IL-10 -819 C/T and TNF-α -308 G/A SNPs were not significantly associated with susceptibility to S. haematobium infection. The prevalence of schistosomiasis is still in the moderate range and is similar in boys and girls.

Acceptability and feasibility of genital self-sampling for the diagnosis of female genital schistosomiasis: a cross-sectional study in Zambia.

Background: Female genital schistosomiasis (FGS) is a neglected and disabling gynaecological disorder that is difficult to diagnose and is part of the wider spectrum of urogenital disease caused by the waterborne parasite Schistosoma haematobium.Over90%ofhumanschistosomiasis cases are found in sub-Saharan Africa with 3.8 million people infected with schistosomes in Zambia. Reported FGS prevalence ranges from 33-75% of those with urinary schistosomiasis in endemic areas, suggesting a potentially high FGS burden in Zambia alone. The Bilharzia and HIV (BILHIV) study evaluated home self-sampling genital collection methods for the diagnosis of FGS. Methods: Eligible participants included non-pregnant, sexually active women aged 18-31 who were previously recruited for the HPTN 071 (PopART) trial in Livingstone, Zambia. Household demographic and symptom questionnaires were administered by community workers. Participants were offered vaginal and cervical self-swabs and a urine cup. Cervicovaginal lavage (CVL) was performed in clinic by midwives. Information was collected from participants on the acceptability and feasibility of genital self-sampling. Results: From January-August 2018, 603 women were enrolled, and 87.3% (527/603) completed clinic follow up. A high proportion of participants indicated that self-collection of specimens was "easy" or "very easy" on a 5-point Likert scale. A high proportion of women would be willing to self-collect all three specimens again in future: vaginal swab 96.7% (583/603), cervical swab 96.5% (582/603), and urine 96.2% (580/603). Overall, 90.0% (543/603) preferred to self-collect samples at home, compared with sampling in the clinic Home-based self-sampling was preferred over provider-based sampling in the clinic due to greater privacy 65.0% (353/543), convenience 51.4% (279/543) and lack of needed transportation 17.7% (96/543). Conclusions: Home based genital self-sampling for FGS diagnosis is highly acceptable. This scalable method may inform future efforts for community-based diagnosis of FGS.

Acceptability and feasibility of genital self-sampling for the diagnosis of female genital schistosomiasis: a cross-sectional study in Zambia

Background: Female genital schistosomiasis (FGS) is a neglected and disabling gynaecological disorder that is difficult to diagnose and is part of the wider spectrum of urogenital disease caused by the waterborne parasite Schistosoma haematobium. Over 90% of human schistosomiasis cases are found in sub-Saharan Africa with 3.8 million people infected with schistosomes in Zambia. Reported FGS prevalence ranges from 33-75% of those with urinary schistosomiasis in endemic areas, suggesting a potentially high FGS burden in Zambia alone. The Bilharzia and HIV (BILHIV) study evaluated home self-sampling genital collection methods for the diagnosis of FGS. Methods: Eligible participants included non-pregnant, sexually active women aged 18-31 who were previously recruited for the HPTN 071 (PopART) trial in Livingstone, Zambia. Household demographic and symptom questionnaires were administered by community workers. Participants were offered vaginal and cervical self-swabs and a urine cup. Cervicovaginal lavage (CVL) was performed in clinic by midwives. Information was collected from participants on the acceptability and feasibility of genital self-sampling. Results: From January-August 2018, 603 women were enrolled, and 87.3% (527/603) completed clinic follow up. A high proportion of participants indicated that self-collection of specimens was “easy” or “very easy” on a 5-point Likert scale. A high proportion of women would be willing to self-collect all three specimens again in future: vaginal swab 96.7% (583/603), cervical swab 96.5% (582/603), and urine 96.2% (580/603). Overall, 90.0% (543/603) preferred to self-collect samples at home, compared with sampling in the clinic Home-based self-sampling was preferred over provider-based sampling in the clinic due to greater privacy 65.0% (353/543), convenience 51.4% (279/543) and lack of needed transportation 17.7% (96/543). Conclusions: Home based genital self-sampling for FGS diagnosis is highly acceptable. This scalable method may inform future efforts for community-based diagnosis of FGS

Effect of integrated schistosomiasis control measures on Oncomelania snails in river channels connecting the Yangtze River in Nanjing City

To evaluate the effectiveness of Oncomelania snails control following the implementation of integrated schistosomiasis control measures in river channels connecting the Yangtze River in endemic areas of Nanjing City. The river channels connecting the Yangtze River with snails in Nanjing City were selected as the study pilots. The integrated schistosomiasis control measures implemented in the study pilots were investigated by means of retrospective analyses and field surveys from 1998 to 2019, and the effectiveness of snail control was evaluated. Integrated control measures with emphases on environmental improvements including water resource projects for schistosomiasis control were implemented in the study pilots during the period from 1998 to 2019, including river bank concretion with 84.51 km in length, marshland cutting and dredging with 50.41 km in length, building 2 sluices and 3 overflow dams, digging one floodway and snail control with chemical treatment that covered an area of 3 370.80 hm2. No Schistosoma japonicum infection had been detected in snails since the completion of the integrated control measures. In addition, snails had been eliminated in 6 river channels connecting the Yangtze River until 2019, with the snail habitats reducing from 214.33 hm2 to 52.22 hm2 in 10 river channels connecting the Yangtze River and the snail density reducing to below 0.1 snails/0.1 m2 in snail-breeding river channels connecting the Yangtze River. The integrated schistosomiasis control measures with emphases on environmental improvements may effectively control snail breeding and spread in rivers connecting the Yangtze River in endemic areas of schistosomiasis; however, the maintenance of the project and snail surveillance and control should be intensified following the completion of the integrated schistosomiasis control measures.

The effect of ecological environmental changes and mollusciciding on snail intermediate host of Schistosoma in Qianjiang city of China from 1985 to 2015

BackgroundSchistosomiasis remains prevalent in Africa, Asia and South America with an estimated burden of 1.9 million disability-adjusted life years in 2016. Targeting snails as a key to success for schistosomiasis control has been widely approved, but the long-term quantitative effects of interventions on snail control that would inform and improve future control programmes are unclear. Over the last six decades, schistosomiasis in China had been brought largely under control, and snail control as supplementary methods or part of integrated multisectoral approaches in different historical periods has played an essential role.MethodsEcological environment factors, prevalence and control data on Oncomelania hupensis between 1985 and 2015 at 5-year intervals in Qianjiang city, China, were collected. A multilevel growth model approach was used to examine the long-term effects of ecological environmental changes and mollusciciding on snail-infested area (SIA) and living snail density (LSD) during the 30 years.ResultsThe variation of SIA was 68.4% in spatial distribution, while the variation of LSD was 68.4% in temporal distribution. Continuous mollusciciding could result in significant LSD reduction, but may not lead to significant SIA reduction. The normalized difference vegetation index (NDVI), patch size coefficient of variation (PSCoV) and mean patch size (MPS) reduction, slightly due to eco-environmental changes decreased SIA, while mean perimeter-area ratio (MPAR) and dry farm-land proportion (DFLP) reduction might increase SIA. Only NDVI and MPAR reduction led to a lower LSD.ConclusionsMollusciciding was more effective in reducing snail density, but it is not easy to eliminate snails completely. Environmental modifications could completely change the snail breeding environment and reduce its infestation area. Due to difficulty of scaling-up the current environmental modifications in waterway network regions, more effective snail control methods are needed. The experience in China could thereby provide guidance for other schistosomiasis endemic areas with a high snail prevalence.

Chronic urticaria associated with schistosomiasis

Schistosomiasis is a tropical disease caused by fluke worms of genus Schistosoma. It can present as acute schistosomiasis and present as fever, cough, headaches, urticaria and cercarial dermatitis and this vary according to the infecting Schistosoma species (Jaureguiberry et al. 2010). Twenty-seven (27) year old female presented to the allergy clinic in Kuala Lumpur Hospital with chronic urticaria for past one year. She presented with persistent severe itchy maculopapular skin eruptions, mostly at the trunk and lower limbs, sparing the face and neck and not associated with angioedema. She had sought treatment from several general practitioners and dermatologists. She was treated with antihistamines, montelukast, and corticosteroid cream but she had temporary relief of her symptoms. She worked as an executive officer in a firm, and she has history of travelling to Cambodia and Thailand regularly for work. She gave history of eating raw salad and seafood in both places. Total Immunoglobulin E (IgE) was elevated (232ku/l). Low specific IgE to seafood. Parasitologic enzyme-linked immunosorbent assay (ELISA) test showed positive titer Immunoglobulin G (IgG) 0.311 to schistosomiasis. Urine microscopy and direct stool microscopy showed negative schistosomiosis eggs. Full blood picture was normal. Ultrasound of abdomen showed normal liver, spleen, kidney, and urinary system. She was given one dose of oral Praziquantel and antihistamines. For about a month, her urticaria and pruritus were less. After 6 months of treatment with praziquantel, a repeat parasitologic ELISA test to IgG was negative to schistosomiasis. Repeated urine microscopy and direct stool microscopy were negative to schistosomiosis. In summary, this woman had presented with chronic urticaria, with history of travelling to endemic areas for schistosomiasis and eating raw food perhaps with contaminated water, it is worthwhile to do some parasitic screening test for common parasitic helminthes, even though it is rarely associated with urticaria. However, cercarial dermatitis due to schistosomiasis have been reported by Folster-Holst R, et al (2001), S.J. Fraser et al (2008), and Kolarova L, et al (1999). To date, schistosomiasis is still considered as one of the main neglected tropical diseases by World Health Organization (WHO).

Evaluation of Praziquantel EffectivenssAfter Decades of Prolonged Use in an Endemic Area in Egypt.

Praziquantel (PZQ) is the preferred drug for schistomiasis treatment because of its safety. As PZQ is used for mass drug administration (MDA) in schistosomiasis endemic areas, the effectiveness of the drug, used solely for decades, should be continuously monitored to detect drug resistance. We aimed to assess the effectiveness of PZQ to cure Schistosoma mansoni infection and to reduce the intensity of infection in an endemic area by estimating the cure rate (CR), egg reduction rate (ERR), and comparing these estimates to the levelsrecommended by the World Health Organization (WHO). A total of 342 children aged 5-15years living in Kafr-El-Sheikh were screened for S. mansoni infection. Stool samples were examined microscopically using Kato-Katz (KK) technique. Among the screened children,106 children had S. mansoni ova in stool, 100 of them received the first dose of PZQ (40mg/kg). Four weeks later, 96 of 100 children received the second dose of PZQ. Stool samples, collected 4 weeks after each dose of PZQ, were examined using KK. The effectiveness of PZQ was assessed based on ERR and CR. CR after the first dose of PZQ was 66.7%, increased to 79.12% after second dose (X2 = 3.05, P = 0.08). Median egg count before treatment was 30.00 (6.00-744), that significantly decreased after two doses of PZQ to 0.00 (0.00-221.33) (Z = 8.29, P = 0.001). Children aged 10-15years showed higher CR (91.3%) than those aged 5-9years (OR = 5.25, CI 1.58-17.40). PZQ is still an effective agent against S. mansoni in endemic areas, achieving a high CR and ERR with predominantly low intensity of infection. Age is a main predictor of response to PZQ.