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1.
BMC Infect Dis ; 24(1): 661, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956479

ABSTRACT

BACKGROUND: After decades of praziquantel mass drug administration (MDA), several countries approach schistosomiasis elimination. Continuing MDA in largely uninfected populations no longer seems justified. Alternative interventions to maintain the gains or accelerate interruption of transmission are needed. We report results, strengths, and shortcomings of novel test-treat-track-test-treat (5T) interventions in low Schistosoma haematobium prevalence areas on Pemba, Tanzania. METHODS: School- and household-based surveys were conducted in 2021 and 2022 to monitor the S. haematobium and microhematuria prevalence and assess the impact of interventions. In 2021, 5T interventions were implemented in 15 low-prevalence areas and included: (i) testing schoolchildren in primary and Islamic schools for microhematuria as a proxy for S. haematobium, (ii) treating positive children, (iii) tracking them to their households and to water bodies they frequented, (iv) testing individuals at households and water bodies, and (v) treating positive individuals. Additionally, test-and-treat interventions were implemented in the 22 health facilities of the study area. RESULTS: The S. haematobium prevalence in the school-based survey in 15 low-prevalence implementation units was 0.5% (7/1560) in 2021 and 0.4% (6/1645) in 2022. In the household-based survey, 0.5% (14/2975) and 0.7% (19/2920) of participants were infected with S. haematobium in 2021 and 2022, respectively. The microhematuria prevalence, excluding trace results, in the school-based survey was 1.4% (21/1560) in 2021 and 1.5% (24/1645) in 2022. In the household-based survey, it was 3.3% (98/2975) in 2021 and 5.4% (159/2920) in 2022. During the 5T interventions, the microhaematuria prevalence was 3.8% (140/3700) and 5.8% (34/594) in children in primary and Islamic schools, respectively, 17.1% (44/258) in household members, and 16.7% (10/60) in people at water bodies. In health facilities, 19.8% (70/354) of patients tested microhematuria-positive. CONCLUSIONS: The targeted 5T interventions maintained the very low S. haematobium prevalence and proved straightforward and feasible to identify and treat many of the few S. haematobium-infected individuals. Future research will show whether 5T interventions can maintain gains in the longer-term and expedite elimination. TRIAL REGISTRATION: ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493 .


Subject(s)
Anthelmintics , Mass Drug Administration , Praziquantel , Schistosoma haematobium , Schistosomiasis haematobia , Tanzania/epidemiology , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/prevention & control , Humans , Child , Animals , Schistosoma haematobium/drug effects , Adolescent , Male , Praziquantel/therapeutic use , Praziquantel/administration & dosage , Female , Prevalence , Mass Drug Administration/methods , Anthelmintics/therapeutic use , Anthelmintics/administration & dosage , Disease Eradication/methods , Schools , Adult , Family Characteristics , Hematuria , Young Adult
2.
Parasit Vectors ; 17(1): 279, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38943214

ABSTRACT

BACKGROUND: Reliance on praziquantel for the treatment and control of schistosomiasis is likely to facilitate the emergence of drug resistance. Combination therapy targeting adult and juvenile schistosome worms is urgently needed to improve praziquantel efficacy and delay the potential development of drug resistance. We assessed the efficacy and safety of single-dose praziquantel combined with single-dose artesunate plus sulfalene-pyrimethamine in the treatment of Kenyan children with schistosomiasis. METHODS: This was an open-label, randomised clinical trial involving 426 school-aged children (7-15 years old) diagnosed with Schistosoma mansoni (by Kato-Katz) or S. haematobium (by urine filtration). They were randomly assigned (1:1:1) to receive a single dose of praziquantel (40 mg/kg), a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate) or combination therapy using a single dose of praziquantel (40 mg/kg) combined with a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate). The primary outcome was cure and egg reduction rates at 6 weeks post-treatment in the available case population. Adverse events were assessed within 3 h after treatment. RESULTS: Of the 426 children enrolled, 135 received praziquantel, 150 received artesunate plus sulfalene-pyrimethamine, and 141 received combination therapy. Outcome data were available for 348 (81.7%) children. For S. mansoni-infected children (n = 335), the cure rates were 75.6%, 60.7%, and 77.8%, and the egg reduction rates were 80.1%, 85.0%, and 88.4% for praziquantel, artesunate plus sulfalene-pyrimethamine, and combination therapy, respectively. For S. haematobium-infected children (n = 145), the corresponding cure rates were 81.4%, 71.1%, and 82.2%, and the egg reduction rates were 95.6%, 97.1%, and 97.7%, respectively. Seventy-one (16.7%) children reported mild-intensity adverse events. The drugs were well tolerated and no serious adverse events were reported. CONCLUSIONS: A single oral dose of praziquantel combined with artesunate plus sulfalene-pyrimethamine cured a high proportion of children with S. haematobium but did not significantly improve the treatment efficacy for either urinary or intestinal schistosomiasis. Sequential administration of praziquantel and artesunate plus sulfalene-pyrimethamine may enhance the efficacy and safety outcomes.


Subject(s)
Anthelmintics , Artemisinins , Artesunate , Drug Therapy, Combination , Praziquantel , Pyrimethamine , Schistosoma haematobium , Schistosoma mansoni , Schistosomiasis haematobia , Schistosomiasis mansoni , Humans , Child , Praziquantel/administration & dosage , Praziquantel/adverse effects , Praziquantel/therapeutic use , Pyrimethamine/administration & dosage , Pyrimethamine/therapeutic use , Pyrimethamine/adverse effects , Animals , Adolescent , Artesunate/administration & dosage , Artesunate/therapeutic use , Female , Male , Schistosomiasis mansoni/drug therapy , Schistosoma haematobium/drug effects , Schistosomiasis haematobia/drug therapy , Schistosoma mansoni/drug effects , Kenya , Artemisinins/administration & dosage , Artemisinins/therapeutic use , Artemisinins/adverse effects , Treatment Outcome , Anthelmintics/administration & dosage , Anthelmintics/adverse effects , Anthelmintics/therapeutic use , Sulfalene/administration & dosage , Sulfalene/therapeutic use , Sulfalene/adverse effects , Drug Combinations , Parasite Egg Count
3.
PLoS Negl Trop Dis ; 18(6): e0011836, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38857289

ABSTRACT

The geographical range of schistosomiasis is affected by the ecology of schistosome parasites and their obligate host snails, including their response to temperature. Previous models predicted schistosomiasis' thermal optimum at 21.7°C, which is not compatible with the temperature in sub-Saharan Africa (SSA) regions where schistosomiasis is hyperendemic. We performed an extensive literature search for empirical data on the effect of temperature on physiological and epidemiological parameters regulating the free-living stages of S. mansoni and S. haematobium and their obligate host snails, i.e., Biomphalaria spp. and Bulinus spp., respectively. We derived nonlinear thermal responses fitted on these data to parameterize a mechanistic, process-based model of schistosomiasis. We then re-cast the basic reproduction number and the prevalence of schistosome infection as functions of temperature. We found that the thermal optima for transmission of S. mansoni and S. haematobium range between 23.1-27.3°C and 23.6-27.9°C (95% CI) respectively. We also found that the thermal optimum shifts toward higher temperatures as the human water contact rate increases with temperature. Our findings align with an extensive dataset of schistosomiasis prevalence in SSA. The refined nonlinear thermal-response model developed here suggests a more suitable current climate and a greater risk of increased transmission with future warming for more than half of the schistosomiasis suitable regions with mean annual temperature below the thermal optimum.


Subject(s)
Schistosoma haematobium , Schistosoma mansoni , Temperature , Animals , Humans , Schistosoma haematobium/physiology , Schistosoma mansoni/physiology , Africa South of the Sahara/epidemiology , Biomphalaria/parasitology , Schistosomiasis/transmission , Schistosomiasis/epidemiology , Schistosomiasis mansoni/transmission , Schistosomiasis mansoni/epidemiology , Bulinus/parasitology , Schistosomiasis haematobia/transmission , Schistosomiasis haematobia/epidemiology , Prevalence
4.
Parasit Vectors ; 17(1): 263, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886811

ABSTRACT

BACKGROUND: Schistosomiasis is a debilitating neglected tropical disease endemic in sub-Saharan Africa. The role of health facilities in the prevention, diagnosis, control, and elimination of schistosomiasis is poorly documented. In a setting targeted for schistosomiasis elimination in Zanzibar, we assessed the prevalence of Schistosoma haematobium among patients seeking care in a health facility and investigated schistosomiasis-related knowledge of staff, and health facilities' capacities and needs for schistosomiasis diagnosis and management. METHODS: We conducted a health facility-based mixed-method study on Pemba Island from June to August 2023. Patients aged ≥ 4 years seeking care in four health facilities were screened for S. haematobium infection using urine filtration and reagent strips. Those patients aged ≥ 10 years were additionally interviewed about signs and symptoms. Staff from 23 health facilities responded to a questionnaire assessing knowledge and practices. Ten staff participated in a focus group discussion (FGD) about capacities and needs for schistosomiasis diagnosis and management. RESULTS: The prevalence of S. haematobium infection in patients attending the health facilities, as determined by the presence of eggs in urine, was 1.1% (8/712). Microhaematuria was detected in 13.3% (95/712) of the patients using reagent strips. Among patients responding to the questionnaire, pelvic pain, pain during sex, and painful urination were reported by 38.0% (237/623), 6.3% (39/623), and 3.2% (20/623), respectively. Among the health facility staff, 90.0% (44/49) and 87.8% (43/49) identified blood in urine and pelvic pain, respectively, as symptoms of urogenital schistosomiasis, 81.6% (40/49) and 93.9% (46/49) reported collecting a urine sample and pursuing a reagent strip test, respectively, for diagnosis, and 87.8% (43/49) administered praziquantel for treatment. The most reoccurring themes in the FGD were the need for more staff training about schistosomiasis, requests for diagnostic equipment, and the need to improve community response to schistosomiasis services in health facilities. CONCLUSIONS: The prevalence of S. haematobium infection in patients seeking care in health facilities in Pemba is very low and similar to what has been reported from recent community-based cross-sectional surveys. The health facility staff had good schistosomiasis-related knowledge and practices. However, to integrate schistosomiasis patient management more durably into routine health facility activities, scalable screening pathways need to be identified and capacities need to be improved by regular staff training, and an unbroken supply of accurate point-of-care diagnostics and praziquantel for the treatment of cases.


Subject(s)
Health Facilities , Schistosoma haematobium , Schistosomiasis haematobia , Humans , Female , Male , Child , Prevalence , Schistosomiasis haematobia/diagnosis , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/prevention & control , Adult , Schistosoma haematobium/isolation & purification , Animals , Adolescent , Disease Eradication , Young Adult , Child, Preschool , Middle Aged , Tanzania/epidemiology , Surveys and Questionnaires , Schistosomiasis/diagnosis , Schistosomiasis/epidemiology , Schistosomiasis/drug therapy , Schistosomiasis/prevention & control , Health Knowledge, Attitudes, Practice , Aged , Health Personnel
5.
BMJ Open ; 14(6): e080395, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38858160

ABSTRACT

INTRODUCTION: Multiplathogen home-based self-sampling offers an opportunity to increase access to screening and treatment in endemic settings with high coinfection prevalence of sexually transmitted (HIV, Trichomonas vaginalis (Tv), human papillomavirus (HPV)) and non-sexually transmitted pathogens (Schistosoma haematobium (Sh)). Chronic coinfections may lead to disability (female genital schistosomiasis) and death (cervical cancer). The Zipime-Weka-Schista (Do self-testing sister!) study aims to evaluate the validity, acceptability, uptake, impact and cost-effectiveness of multipathogen self-sampling for genital infections among women in Zambia. METHODS AND ANALYSIS: This is a longitudinal cohort study aiming to enrol 2500 non-pregnant, sexually active and non-menstruating women aged 15-50 years from two districts in Zambia with 2-year follow-up. During home visits, community health workers offer HIV and Tv self-testing and cervicovaginal self-swabs for (1) HPV by GeneXpert and, (2) Sh DNA detection by conventional (PCR)and isothermal (recombinase polymerase assay) molecular methods. Schistosoma ova and circulating anodic antigen are detected in urine. At a clinic follow-up, midwives perform the same procedures and obtain hand-held colposcopic images. High-risk HPV positive women are referred for a two-quadrant cervical biopsy according to age and HIV status. A cost-effectiveness analysis is conducted in parallel. ETHICS AND DISSEMINATION: The University of Zambia Biomedical Research Ethics Committee (UNZABREC) (reference: 1858-2021), the London School of Hygiene and Tropical Medicine (reference: 25258), Ministry of Health and local superintendents approved the study in September 2021.Written informed consent was obtained from all participants prior to enrolment. Identifiable data collected are stored securely and their confidentiality is protected in accordance with the Data Protection Act 1998.


Subject(s)
Cost-Benefit Analysis , HIV Infections , Mass Screening , Papillomavirus Infections , Humans , Female , Zambia/epidemiology , Longitudinal Studies , Adult , Adolescent , Young Adult , Middle Aged , Papillomavirus Infections/diagnosis , Papillomavirus Infections/epidemiology , HIV Infections/diagnosis , HIV Infections/epidemiology , Mass Screening/methods , Mass Screening/economics , Coinfection/diagnosis , Self-Testing , Animals , Schistosomiasis haematobia/diagnosis , Schistosomiasis haematobia/epidemiology , Trichomonas Vaginitis/diagnosis , Trichomonas Vaginitis/epidemiology , Trichomonas vaginalis/isolation & purification , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/virology , Human Papillomavirus Viruses
6.
BMJ Open ; 14(6): e079690, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38889945

ABSTRACT

BACKGROUND: Urogenital schistosomiasis (UGS) caused by Schistosoma haematobium is endemic in Southern Tanzania. The disease has significant implications for both socioeconomic and public health. Because infections with S. haematobium usually peak in childhood, the majority of studies have concentrated on school-aged children leaving other groups such as males which might be continuous reservoir of infection transmission. However, despite its chronic consequences in the male population, the disease has received insufficient attention, especially in sub-Saharan Africa. This study was conducted to describe the previous and current schistosomiasis status among adult males living in high-endemic areas of southern Tanzania DESIGN, SETTING AND PARTICIPANTS: A descriptive cross-sectional study was employed to gather data on the prevalence of UGS among adult men residing at schistosomiasis endemic in the Mtama District Council. Quantitative methods of data collection which included questionnaire and laboratory procedures were used. RESULTS: Out of 245 participants, macrohaematuria and microhaematuria were found in 12 (4.9%, 95% CI 2.4% to 7.8%) and 66 (26.9%, 95% CI 21.6% to 32.7%) participants, respectively. S. haematobium ova were recovered from the urine samples of 54 (22.0%, 95% CI 16.7% to 27.3%) participants. The median intensity of infection was 20 eggs per 10 mL of urine ranging from 1 to 201 eggs per 10 mL of urine (IQR) 60.5). Out of 245 participants 33 (13.5% 95% CI 9.0% to 17.6%) had light intensity of infection and 21 (38.9%, 95% CI; 25.0% to 52.5%) had heavy intensity of infection. Overall, the prevalence of heavy intensity of infection was 8.6% (95% CI 4.9% to 12.6%). The prevalence and intensity of UGS varied significantly by age, marital status and village of residence. CONCLUSION: This study sheds light on the prevalence of UGS among adult males in endemic areas of southern Tanzania. The results highlight the urgent need for comprehensive intervention strategies to address the burden of the disease.


Subject(s)
Endemic Diseases , Schistosoma haematobium , Schistosomiasis haematobia , Humans , Male , Tanzania/epidemiology , Cross-Sectional Studies , Schistosomiasis haematobia/epidemiology , Adult , Prevalence , Young Adult , Schistosoma haematobium/isolation & purification , Middle Aged , Animals , Adolescent , Hematuria/epidemiology
7.
Am J Trop Med Hyg ; 111(1): 73-79, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38772355

ABSTRACT

The World Health Organization (WHO) 2030 Roadmap aims to eliminate schistosomiasis as a public health issue, targeting reductions in the heavy intensity of infections. Previous studies, however, have predominantly used prevalence as the primary indicator of schistosomiasis. We introduce several machine learning (ML) algorithms to predict infection intensity categories, using morbidity prevalence, with the aim of assessing the elimination of schistosomiasis in Africa, as outlined by the WHO. We obtained morbidity prevalence and infection intensity data from the Expanded Special Project to Eliminate Neglected Tropical Diseases, which spans 12 countries in sub-Saharan Africa. We then used a series of ML algorithms to predict the prevalence of infection intensity categories for Schistosoma haematobium and Schistosoma mansoni, with morbidity prevalence and several relevant environmental and demographic covariates from remote-sensing sources. The optimal model had high accuracy and stability; it achieved a mean absolute error (MAE) of 0.02, a root mean square error (RMSE) of 0.05, and a coefficient of determination (R2) of 0.84 in predicting heavy-intensity prevalence for S. mansoni; and an MAE of 0.02, an RMSE of 0.04, and an R2 value of 0.81 for S. haematobium. Based on this optimal model, we found that most areas in the surveyed countries have not achieved the target of the WHO road map for 2030. The ML algorithms used in our analysis showed a high overall predictive power in estimating infection intensity for each species, and our methods provided a low-cost, effective approach to evaluating the disease target in Africa set in the WHO road map for 2030.


Subject(s)
Machine Learning , Schistosoma haematobium , Schistosoma mansoni , Schistosomiasis mansoni , World Health Organization , Humans , Prevalence , Animals , Schistosomiasis mansoni/epidemiology , Schistosomiasis mansoni/prevention & control , Schistosomiasis mansoni/diagnosis , Schistosoma mansoni/isolation & purification , Africa South of the Sahara/epidemiology , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/prevention & control , Schistosomiasis haematobia/diagnosis , Algorithms , Schistosomiasis/epidemiology , Schistosomiasis/prevention & control , Schistosomiasis/diagnosis , Africa/epidemiology
8.
Trends Parasitol ; 40(7): 546-548, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38821840

ABSTRACT

Highlighting recent literature, we review the epidemiological and clinical importance of male genital schistosomiasis (MGS) in Malawi. We then discuss why individual disease management is an unmet public health challenge and outline how future interventions should be better set within routine services of HIV and men's sexual and reproductive health clinics.


Subject(s)
Schistosomiasis haematobia , Malawi/epidemiology , Humans , Male , Schistosomiasis haematobia/epidemiology , Animals
9.
PLoS One ; 19(5): e0302554, 2024.
Article in English | MEDLINE | ID: mdl-38696499

ABSTRACT

BACKGROUND: Female genital schistosomiasis (FGS) is a gynaecological complication of urinary schistosomiasis (US) with an estimated burden of 20-120 million cases in endemic areas. A neglected sexual and reproductive health disease in sub-Saharan Africa, FGS increases susceptibility to sexually transmitted infections including cervical cancer and infertility among other morbidities. However, there appears to be limited FGS knowledge among practicing and pre-service health providers with implications for control. We assessed FGS awareness among final-year midwifery students who would soon be delivering primary maternal and reproductive health care. METHODS: A cross-sectional study was conducted among 193 randomly selected final-year students from all three midwifery training institutions in the Volta region of Ghana in August/September, 2022. Data on participants' demographics and knowledge of the transmission, signs and symptoms, complications, treatment and prevention of both FGS and US were collected using structured questionnaires. Summary statistics were presented as frequencies, proportions and percentages. RESULTS: Only 23.3% (44/189) of participants had heard about FGS compared to 64% (123/192) for US. Of the former, 42 (95%), 40 (91%) and 36 (81.8%) respectively identified genital itching/burning sensation, bloody vaginal discharge and pelvic pain/pain during intercourse as part of the symptoms of FGS. Less than a third (13/44) and about half (25/44) of those who indicated hearing about FGS knew it can be a risk for ectopic pregnancies and infertility respectively. Majority of these participants, 40 (91%), wrongly selected antibiotics as treatment for FGS while 9 indicated it is prevented by sleeping in insecticide-treated nets. CONCLUSION: Awareness of FGS was limited among the study participants. The high prevalence of knowledge of some FGS symptoms related to the genitalia needs cautious interpretation. Health care training institutions must make deliberate efforts to highlight FGS in the training of midwives as the condition has diagnostic and management implications for some sexual and reproductive health conditions.


Subject(s)
Clinical Competence , Genital Diseases, Female , Midwifery , Neglected Diseases , Schistosomiasis haematobia , Students, Nursing , Genital Diseases, Female/diagnosis , Genital Diseases, Female/parasitology , Schistosomiasis haematobia/complications , Schistosomiasis haematobia/diagnosis , Female , Ghana , Cross-Sectional Studies , Neglected Diseases/diagnosis , Neglected Diseases/parasitology , Adolescent , Young Adult , Adult
10.
Acta Trop ; 256: 107232, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38729329

ABSTRACT

The World Health Organization calls for schistosomiasis endemic countries to regularly monitor the efficacy of Praziquantel (PZQ) drug, the only antischistosomal drug used for four decades in Tanzania. In response to that call, the current study investigated the efficacy of single dose of PZQ against Schistosoma haematobium during the high transmission season and further assessed, the sensitivity and specificity of urine reagent strips before and after treatment. The study recruited a total of 2,498 -children aged (4 -17 years old) who provided a single urine sample that was visually examined for macro-haematuria, then using urine dipstick and urine filtration technique for microhaematuria and the presence of S. haematobium eggs. The baseline prevalence of S. haematobium eggs positive based on urine filtration test was 29.2 % (95 %CI:27.5-31.0) and that of microhaematuria was 43.1 % (95 %CI:41.1-45.0). Of the infected participants, 40.9 % (95 %CI:37.4-44.6) had a heavy intensity of infection and the geometrical mean intensity (GMI) of infection was 33.7 eggs/10mls of urine. A single dose of PZQ reduced the prevalence of infection to 16.2 %, the GMI of infection to 18.8eggs/10mls of urine and that of microhaematuria to 27.9 %. Cure rate and egg reduction rates (ERR) were 83.8 % and 44.3 % respectively. At baseline, the sensitivity and specificity of the urine reagent strips were 59.7 % and 93.8 %, whereas at post-treatment they were 16.7 % and 93.6 %. When PZQ drug is administered during the high transmission season, its efficacy in term of ERR is poor. The urine reagent strips had low sensitivity but high specificity at pre-and-post PZQ treatment.


Subject(s)
Anthelmintics , Praziquantel , Reagent Strips , Schistosoma haematobium , Schistosomiasis haematobia , Sensitivity and Specificity , Praziquantel/therapeutic use , Praziquantel/administration & dosage , Tanzania/epidemiology , Humans , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/urine , Schistosomiasis haematobia/epidemiology , Child , Animals , Child, Preschool , Female , Male , Anthelmintics/therapeutic use , Anthelmintics/administration & dosage , Schistosoma haematobium/drug effects , Adolescent , Prevalence , Urine/parasitology , Urine/chemistry , Treatment Outcome , Parasite Egg Count
11.
PLoS Negl Trop Dis ; 18(5): e0012102, 2024 May.
Article in English | MEDLINE | ID: mdl-38718065

ABSTRACT

BACKGROUND: Female genital schistosomiasis (FGS), caused by the parasite Schistosoma haematobium (Sh), is prevalent in Sub-Saharan Africa. FGS is associated with sexual dysfunction and reproductive morbidity, and increased prevalence of HIV and cervical precancerous lesions. Lack of approved guidelines for FGS screening and diagnosis hinder accurate disease burden estimation. This study evaluated FGS burden in two Sh-endemic areas in Southern Malawi by visual and molecular diagnostic methods. METHODOLOGY/PRINCIPAL FINDINGS: Women aged 15-65, sexually active, not menstruating, or pregnant, were enrolled from the MORBID study. A midwife completed a questionnaire, obtained cervicovaginal swab and lavage, and assessed FGS-associated genital lesions using hand-held colposcopy. 'Visual-FGS' was defined as specific genital lesions. 'Molecular-FGS' was defined as Sh DNA detected by real-time PCR from swabs. Microscopy detected urinary Sh egg-patent infection. In total, 950 women completed the questionnaire (median age 27, [IQR] 20-38). Visual-and molecular-FGS prevalence were 26·9% (260/967) and 8·2% (78/942), respectively. 6·5% of women with available genital and urinary samples (38/584) had egg-patent Sh infection. There was a positive significant association between molecular- and visual-FGS (AOR = 2·9, 95%CI 1·7-5·0). 'Molecular-FGS' was associated with egg-patent Sh infection (AOR = 7·5, 95% CI 3·27-17·2). Some villages had high 'molecular-FGS' prevalence, despite <10% prevalence of urinary Sh among school-age children. CONCLUSIONS/SIGNIFICANCE: Southern Malawi carries an under-recognized FGS burden. FGS was detectable in villages not eligible for schistosomiasis control strategies, potentially leaving girls and women untreated under current WHO guidelines. Validated field-deployable methods could be considered for new control strategies.


Subject(s)
Schistosoma haematobium , Schistosomiasis haematobia , Humans , Female , Malawi/epidemiology , Adult , Cross-Sectional Studies , Adolescent , Schistosomiasis haematobia/epidemiology , Young Adult , Middle Aged , Risk Factors , Schistosoma haematobium/isolation & purification , Schistosoma haematobium/genetics , Animals , Aged , Prevalence , Surveys and Questionnaires , Endemic Diseases
12.
Acta Parasitol ; 69(2): 1267-1274, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38753102

ABSTRACT

PURPOSE: This study aimed to develop and evaluate a lateral flow card for the detection of active Schistosoma haematobium infection. METHODS: In order to prepare the immunochromatography lateral flow strip (ICLFS), antibodies purified from schistosomiasis were conjugated passively with gold nanoparticles using a potassium carbonate buffer. RESULTS: The novel ICLFS was able to correctly identify 64 out of 67 samples of schistosomiasis, 6 out of 90 samples of other parasites, and 0 out of 27 control samples. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were 95.5%, 93.3%, 90%, and 91.4% respectively. Comparatively, the sensitivity, specificity, NPV, and PPV of sandwich enzyme-linked immunosorbent assays (ELISA) conjugated with gold nanoparticles (AuNPs) were 91.1%, 88.8%, 85.9%, and 84.4% respectively. The increased sensitivity and specificity of ICLFS produced superior results to those of sandwich ELISA. CONCLUSION: In conclusion, ICLFS is more beneficial and precise than sandwich ELISA for detection of S. haematobium infection at early stage.


Subject(s)
Antigens, Helminth , Chromatography, Affinity , Gold , Metal Nanoparticles , Schistosoma haematobium , Schistosomiasis haematobia , Sensitivity and Specificity , Gold/chemistry , Humans , Schistosoma haematobium/immunology , Metal Nanoparticles/chemistry , Animals , Schistosomiasis haematobia/diagnosis , Chromatography, Affinity/methods , Enzyme-Linked Immunosorbent Assay/methods , Antibodies, Helminth/blood , Reagent Strips
13.
Parasite Immunol ; 46(4): e13027, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38587985

ABSTRACT

Malaria in pregnancy has severe consequences for the mother and foetus. Antibody response to specific malaria vaccine candidates (MVC) has been associated with a decreased risk of clinical malaria and its outcomes. We studied Plasmodium falciparum (Pf) and Schistosoma haematobium (Sh) infections and factors that could influence antibody responses to MVC in pregnant women. A total of 337 pregnant women receiving antenatal care (ANC) and 139 for delivery participated in this study. Pf infection was detected by qPCR and Sh infection using urine filtration method. Antibody levels against CSP, AMA-1, GLURP-R0, VAR2CSA and Pfs48/45 MVC were quantified by ELISA. Multivariable linear regression models identified factors associated with the modulation of antibody responses. The prevalence of Pf and Sh infections was 27% and 4% at ANC and 7% and 4% at delivery. Pf infection, residing in Adidome and multigravidae were positively associated with specific IgG response to CSP, AMA-1, GLURP-R0 and VAR2CSA. ITN use and IPTp were negatively associated with specific IgG response to GLURP-R0 and Pfs48/45. There was no association between Sh infection and antibody response to MVC at ANC or delivery. Pf infections in pregnant women were positively associated with antibody response to CSP, GLURP-R0 and AMA-1. Antibody response to GLURP-R0 and Pfs48/45 was low for IPTp and ITN users. This could indicate a lower exposure to Pf infection and low malaria prevalence observed at delivery.


Subject(s)
Malaria Vaccines , Malaria, Falciparum , Schistosomiasis haematobia , Animals , Humans , Female , Pregnancy , Plasmodium falciparum , Schistosoma haematobium , Antibody Formation , Pregnant Women , Antigens, Protozoan , Antibodies, Protozoan , Malaria, Falciparum/epidemiology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/complications , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/prevention & control , Schistosomiasis haematobia/complications , Immunoglobulin G
14.
BMC Public Health ; 24(1): 952, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38566137

ABSTRACT

BACKGROUND: Urogenital schistosomiasis (UgS) remains a persistent health challenge among adolescents in Anambra State, Nigeria, despite ongoing control efforts. Mass praziquantel treatment programs, initiated in 2013, primarily target primary school-aged children (5-14 years old), leaving adolescents (10-19 years old) enrolled in secondary schools vulnerable to urogenital schistosomiaisis. Additionally, the extent of female genital schistosomiasis (FGS), a neglected gynaecological manifestation of UgS remains unclear. METHODOLOGY: To address these gaps, a cross-sectional study was conducted in Anaocha Local Government Area from February to May 2023. Four hundred and seventy consenting adolescents aged 10-19 years were enrolled. Urinalysis including urine filtration was employed to confirm haematuria and detect urogenital schistosomiasis (UGS) among the participants. For females with heavy infections (≥ 50 eggs/10 ml urine), a gynaecologist performed colposcopy examinations, complemented by acetic acid and Lugol's iodine staining to assess for female genital schistosomiasis (FGS) lesions or other related reproductive health conditions. Socio-demographic data, including information on potential risk factors, were systematically collected using the Kobo ToolBox software, following gender-sensitive data collection guidelines. Data were analysed using SPSS version 25, incorporating descriptive statistics, multinomial logistic regression, odds ratios, and significance testing. RESULTS: Among the 470 adolescents (52.8% females, 47.2% males) examined, an overall UgS prevalence of 14.5% was observed, with an average of 5.25 eggs per 10 ml of urine. Females had a slightly higher prevalence (16.1%), and 7.5% had heavy infections. Although gender differences in infection rates were not statistically significant, males had slightly higher odds of infection (OR: 1.332; 95% CI: 0.791-2.244; p-value: 0.280). Adolescents aged 10-14 had the highest prevalence, with significantly increased odds of infection (OR: 1.720; 95% CI: 1.012-2.923; p-value: 0.045). Colposcopy examinations of females with heavy infections revealed FGS lesions and co-infections with Trichomonas vaginalis. Haematuria, though prevalent (24.6%), was not the sole indicator, as those without it faced significantly higher odds of infection (OR: 2.924; 95% CI: 1.731-4.941; p-value: 0.000). Dysuria and genital itching/burning sensation were other UgS and FGS associated symptoms. Direct water contact was associated with higher infection odds (OR: 2.601; 95% CI: 1.007-6.716; p-value: 0.048). Various risk factors were associated with UgS. CONCLUSION: The study highlights the need for a comprehensive Urogenital Schistosomiasis (UGS) control strategy that includes secondary school adolescents, emphasizes risk factor management, promotes safe water practices, and raises awareness about UGS and Female Genital Schistosomiasis (FGS) among adolescents, thus improving control efforts and mitigating this health challenge in the region.


Subject(s)
Schistosomiasis haematobia , Male , Child , Humans , Female , Adolescent , Child, Preschool , Young Adult , Adult , Animals , Schistosomiasis haematobia/diagnosis , Schistosomiasis haematobia/epidemiology , Cross-Sectional Studies , Hematuria/epidemiology , Nigeria/epidemiology , Genitalia, Female , Prevalence , Water , Schistosoma haematobium
15.
J Infect Dis ; 229(6): 1904-1908, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38669235

ABSTRACT

We are currently witnessing the endemization of urogenital schistosomiasis in southern Europe. The incriminated parasite is a hybrid between a human parasite and a livestock parasite. Using an experimental evolutionary protocol, we created hybrid lines from pure strains of both parasite species. We showed that the host spectrum of the human parasite is enlarged to the livestock parasite after genomic introgression. We also evidenced that the tropism of the parasites within the host changes and that some hybrid lines are more virulent than the parental strains. These results engage a paradigm shift from human to zoonotic transmission of urogenital schistosomiasis.


Subject(s)
Hybridization, Genetic , Zoonoses , Animals , Humans , Zoonoses/transmission , Zoonoses/parasitology , Schistosomiasis haematobia/transmission , Schistosomiasis haematobia/parasitology , Schistosoma haematobium/genetics , Mice
16.
PLoS Negl Trop Dis ; 18(4): e0011472, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38620029

ABSTRACT

BACKGROUND: Natural interspecific hybridization between the human parasite (Schistosoma haematobium [Sh]) and bovine parasites (Schistosoma bovis [Sb], Schistosoma curassoni [Sc]) is increasingly reported in Africa. We developed a multi-locus PCR DNA-Seq strategy that amplifies two unlinked nuclear (transITS, BF) and two linked organellar genome markers (CO1, ND5) to genotype S. haematobium eggs collected from infected people in Ile Oluji/Oke Igbo, Ondo State (an agrarian community) and Kachi, Jigawa State (a pastoral community) in Southwestern and Northern Nigeria, respectively. PRINCIPAL FINDINGS: Out of a total of 219 urine samples collected, 57 were positive for schistosomes. All patients from Jigawa state possessed an Sh mitochondrial genome and were infected with a genetic profile consistent with an Sh x Sb hybrid based on sequences obtained at CO1, ND5, transITS and BF nuclear markers. Whereas samples collected from Ondo state were more varied. Mitonuclear discordance was observed in all 17 patients, worms possessed an Sb mitochondrial genome but one of four different genetic profiles at the nuclear markers, either admixed (heterozygous between Sh x Sc or Sh x Sb) at both markers (n = 10), Sh at BF and admixed at transITS (Sh x Sc) (n = 5), admixed (Sh x Sc) at BF and homozygous Sc at transITS (n = 1) or homozygous Sh at BF and homozygous Sc at transITS (n = 1). SIGNIFICANCE: Previous work suggested that zoonotic transmission of S. bovis in pastoral communities, where humans and animals share a common water source, is a driving factor facilitating interspecific hybridization. However, our data showed that all samples were hybrids, with greater diversity identified in Southwestern Nigeria, a non-pastoral site. Further, one patient possessed an S. bovis mitochondrial genome but was homozygous for S. haematobium at BF and homozygous for S. curassoni at transITS supporting at least two separate backcrosses in its origin, suggesting that interspecific hybridization may be an ongoing process.


Subject(s)
Hybridization, Genetic , Schistosoma haematobium , Schistosomiasis haematobia , Animals , Nigeria/epidemiology , Humans , Schistosoma haematobium/genetics , Schistosoma haematobium/isolation & purification , Schistosoma haematobium/classification , Schistosomiasis haematobia/parasitology , Schistosomiasis haematobia/epidemiology , Male , Female , Genotype , DNA, Helminth/genetics , Genome, Mitochondrial , Adult
17.
PLoS Negl Trop Dis ; 18(4): e0012101, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38620032

ABSTRACT

BACKGROUND: Schistosomiasis is endemic in Nigeria, and the treatment is largely concentrated on children enrolled in schools. Consequently, the coverage of non-enrolled school-aged children is often neglected. Ajagba and Awosan are two communities in Nigeria that have never had any control intervention. Hence, this survey was designed to determine the endemicity of urogenital schistosomiasis and to evaluate the efficacy of a single-dose praziquantel in the communities. METHODS: Urine sample (10 mL) of each participant from Ajagba and Awosan communities was filtered through 12µm polycarbonate filter. The filter was placed on a microscope slide, and stained with a drop of 1% Lugol iodine solution. The stained slides were examined under the microscope and the numbers of S. haematobium eggs were counted. Water contact sites were searched for snail hosts and the snails collected were shed for Schistosoma cercariae. Data were analyzed using SPSS version 24.0 and the significance level was set at 95%. RESULTS: The overall prevalence of infection in the Ajagba community was 45.6% with a mean intensity of 61.1 ± 144.5 eggs/10 mL of urine, while the prevalence of infection in the Awosan community was 5.7% with a mean intensity of 1.4 ± 6.8 eggs/10 mL of urine. The school-aged children had a prevalence and mean intensity of infection of 73.1% and 111.6 ± 177.9 eggs/10 mL of urine, respectively. Following treatment, women had a higher egg reduction rate than men (p = 0.0283). Bulinus globosus were found in Ajagba but not in Awosan, with 5.7% shedding Schistosoma spp, cercariae. CONCLUSION: Urogenital schistosomiasis was hyperendemic in the Ajagba community, and hypoendemic in the Awosan community. The presence of Bulinus globosus supported the transmission of the schistosomiasis in the Ajagba community. Communities where schistosomiasis is still actively transmitted in Nigeria should be identified for effective intervention through the MDA programs.


Subject(s)
Anthelmintics , Praziquantel , Rural Population , Schistosoma haematobium , Schistosomiasis haematobia , Nigeria/epidemiology , Humans , Praziquantel/administration & dosage , Praziquantel/therapeutic use , Child , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Animals , Female , Male , Adolescent , Schistosoma haematobium/drug effects , Anthelmintics/administration & dosage , Anthelmintics/therapeutic use , Adult , Young Adult , Prevalence , Snails/parasitology , Child, Preschool , Middle Aged , Endemic Diseases , Parasite Egg Count
18.
PLoS Negl Trop Dis ; 18(3): e0011798, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38536861

ABSTRACT

OBJECTIVE: Female Genital Schistosomiasis (FGS) causes intravaginal lesions and symptoms that could be mistaken for sexually transmitted diseases or cancer. In adults, FGS lesions [grainy sandy patches (GSP), homogenous yellow patches (HYP), abnormal blood vessels and rubbery papules] are refractory to treatment. The effect of treatment has never been explored in young women; it is unclear if gynaecological investigation will be possible in this young age group (16-23 years). We explored the predictors for accepting anti-schistosomal treatment and/or gynaecological reinvestigation in young women, and the effects of anti-schistosomal mass-treatment (praziquantel) on the clinical manifestations of FGS at an adolescent age. METHOD: The study was conducted between 2011 and 2013 in randomly selected, rural, high schools in Ilembe, uThungulu and Ugu Districts, KwaZulu-Natal Province, East Coast of South Africa. At baseline, gynaecological investigations were conducted in female learners in grades 8 to 12, aged 16-23 years (n = 2293). Mass-treatment was offered in the low-transmission season between May and August (a few in September, n = 48), in accordance with WHO recommendations. Reinvestigation was offered after a median of 9 months (range 5-14 months). Univariate, multivariable and logistic regression analysis were used to measure the association between variables. RESULTS: Prevalence: Of the 2293 learners who came for baseline gynaecological investigations, 1045 (46%) had FGS lesions and/or schistosomiasis, 209/1045 (20%) had GSP; 208/1045 (20%) HYP; 772/1045 (74%) had abnormal blood vessels; and 404/1045 (39%) were urine positive. Overall participation rate for mass treatment and gynaecological investigation: Only 26% (587/2293) learners participated in the mass treatment and 17% (401/2293) participated in the follow up gynaecological reinvestigations. Loss to follow-up among those with FGS: More than 70% of learners with FGS lesions at baseline were lost to follow-up for gynaecological investigations: 156/209 (75%) GSP; 154/208 (74%) HYP; 539/722 (75%) abnormal blood vessels; 238/404 (59%) urine positive. The grade 12 pupil had left school and did not participate in the reinvestigations (n = 375; 16%). Follow-up findings: Amongst those with lesions who came for both treatment and reinvestigation, 12/19 still had GSP, 8/28 had HYP, and 54/90 had abnormal blood vessels. Only 3/55 remained positive for S. haematobium ova. Factors influencing treatment and follow-up gynaecological investigation: HIV, current water contact, water contact as a toddler and urinary schistosomiasis influenced participation in mass treatment. Grainy sandy patches, abnormal blood vessels, HYP, previous pregnancy, current water contact, water contact as a toddler and father present in the family were strongly associated with coming back for follow-up gynaecological investigation. Challenges in sample size for follow-up analysis of the effect of treatment: The low mass treatment uptake and loss to follow up among those who had baseline FGS reduced the chances of a larger sample size at follow up investigation. However, multivariable analysis showed that treatment had effect on the abnormal blood vessels (adjusted odds ratio = 2.1, 95% CI 1.1-3.9 and p = 0.018). CONCLUSION: Compliance to treatment and gynaecological reinvestigation was very low. There is need to embark on large scale awareness and advocacy in schools and communities before implementing mass-treatment and investigation studies. Despite challenges in sample size and significant loss to follow-up, limiting the ability to fully understand the treatment's effect, multivariable analysis demonstrated a significant treatment effect on abnormal blood vessels.


Subject(s)
Genital Diseases, Female , Schistosomiasis haematobia , Adult , Pregnancy , Animals , Female , Adolescent , Humans , Praziquantel/therapeutic use , South Africa , Schistosoma haematobium , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/diagnosis , Genitalia, Female , Water
19.
Lancet Microbe ; 5(4): e366-e378, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38467130

ABSTRACT

BACKGROUND: Accurate diagnosis is pivotal for implementing strategies for surveillance, control, and elimination of schistosomiasis. Despite their low sensitivity in low-endemicity areas, microscopy-based urine filtration and the Kato-Katz technique are considered as reference diagnostic tests for Schistosoma haematobium and Schistosoma mansoni infections, respectively. We aimed to collate all available evidence on the accuracy of other proposed diagnostic techniques. METHODS: In this systematic review and meta-analysis, we searched PubMed, Embase, the Cochrane Library, and LILACS for studies published from database inception to Dec 31, 2022, investigating the sensitivity and specificity of diagnostic tests for S haematobium and S mansoni infections against Kato-Katz thick smears or urine microscopy (reference tests) involving adults (aged ≥18 years), school-aged children (aged 7 to 18 years), or preschool-aged children (aged 1 month to 7 years). We extracted raw data on true positives, true negatives, false positives, and false negatives for the diagnostic tests and data on the number of participants, study authors, publication year, journal, study design, participants' age and sex, prevalence of Schistosoma infection, and treatment status. To account for imperfect reference tests, we used a hierarchical Bayesian latent class meta-analysis to model test accuracy. FINDINGS: Overall, we included 121 studies, assessing 28 different diagnostic techniques. Most studies (103 [85%] of 121) were done in Africa, 14 (12%) in South America, one (1%) in Asia, and one (1%) in an unknown country. Compared with the reference test, Kato-Katz thick smears, circulating cathodic antigen urine cassette assay version 1 (CCA1, 36 test comparisons) had excellent sensitivity (95% [95% credible interval 88-99]) and reasonable specificity (74% [63-83]) for S mansoni. ELISA-based tests had a performance comparable to circulating cathodic antigen, but there were few available test comparisons. For S haematobium, proteinuria (42 test comparisons, sensitivity 73% [62-82]; specificity 94% [89-98]) and haematuria (75 test comparisons, sensitivity 85% [80-90]; specificity 96% [92-99]) reagent strips showed high specificity, with haematuria reagent strips having better sensitivity. Despite limited data, nucleic acid amplification tests (NAATs; eg, PCR or loop-mediated isothermal amplification [LAMP]) showed promising results with sensitivity estimates above 90%. We found an unclear risk of bias of about 70% in the use of the reference or index tests and of 50% in patient selection. All analyses showed substantial heterogeneity (I2>80%). INTERPRETATION: Although NAATs and immunological diagnostics show promise, the limited information available precludes drawing definitive conclusions. Additional research on diagnostic accuracy and cost-effectiveness is needed before the replacement of conventional tests can be considered. FUNDING: WHO and Luxembourg Institute of Health.


Subject(s)
Schistosoma mansoni , Schistosomiasis haematobia , Child , Child, Preschool , Adult , Animals , Humans , Adolescent , Schistosoma haematobium , Hematuria/diagnosis , Reagent Strips , Microscopy , Bayes Theorem , Feces , Antigens, Helminth/urine , Urinalysis , Schistosomiasis haematobia/diagnosis , Diagnostic Tests, Routine/methods
20.
PLoS Negl Trop Dis ; 18(3): e0011954, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38466660

ABSTRACT

Schistosoma haematobium, the parasite that causes urogenital schistosomiasis, is widely prevalent in Tanzania. In addition to well-known effects on the urinary tract, S. haematobium also causes clinically- evident damage to the reproductive tract in approximately half of infected women, which is known as female genital schistosomiasis (FGS). FGS has major gynecologic and social consequences on women's reproductive health, yet little information is available regarding FGS in Tanzania. To cover that gap, we conducted the present scoping review to examine the epidemiology of FGS in Tanzania (both in the mainland and Zanzibar island) and to make recommendations for future work in this area. The available evidence from community-based and hospital-based retrospective studies indicates that FGS is a significant health problem in the country. Very few community-based studies have been reported from mainland Tanzania, and Zanzibar. Our review highlights the scarcity of efforts to address FGS in Tanzania and the need for additional community-based studies. The studies will help us understand the true burden of the disease nationwide, to assess the impact of praziquantel on FGS lesions, and to address social and mental health in relation to FGS. This review emphasizes integration of delivery of FGS related services in primary health care systems through the reproductive health clinics which covers sexually transmitted infections, HIV and cervical cancer screening. These actions are essential if this neglected gynecological disease is to be addressed in Tanzania.


Subject(s)
Genital Diseases, Female , Schistosomiasis haematobia , Uterine Cervical Neoplasms , Animals , Female , Humans , Tanzania/epidemiology , Public Health , Retrospective Studies , Early Detection of Cancer , Genitalia, Female/parasitology , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/diagnosis , Schistosoma haematobium , Genital Diseases, Female/parasitology
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