Social science perspectives on schistosomiasis control in Africa: past trends and future directions

Communities' knowledge, perceptions and preventive practices on soil-transmitted helminthes in Jimma, Oromia, Ethiopia: Formative mixed study

BACKGROUND

Soil-transmitted helminthes (STH) infections are one of the most common neglected tropical diseases. It has become one of a significant public health problem programmatically aimed for prevention and control in Ethiopia. Limited evidence is available on communities' knowledge, perceptions, and practices regarding STH particularly in rural settings of Jimma, Ethiopia.

METHODS

A community-based cross-sectional study triangulated with the qualitative method was conducted. The survey included 732 sampled rural households. Linear regression was used to assess association between predictors of knowledge and preventive practices of STH; likewise logistic regression was used to identify the predictors of hand washing practice at critical times. Kruskal-Wallis and Mann-Whitney tests were done to test differences in median risk perception score by socio-demographic factors. Qualitative data were collected through 7 key informant interviews, 6 focus group discussions and 7 expert group discussions then transcribed verbatim. Then, the data were coded, categorized and thematized using the Atlas ti.7.1.4 software package.

RESULTS

Almost all of the respondents (99.6%) had heard of STH. The prevalence of comprehensive knowledge, risk perception and preventive practices towards STH were 46.7%:(95%CI:43.2, 50.4), 55.2%: (95%CI:51.2,59) and 44.4%:(95%CI:40.8, 48.2) respectively. Likewise, the magnitude of knowledge and practice of hand washing at critical times were 42.5%: (95%CI: 38.7,45.9) and 43.9%: (95%CI: 40, 47.5) respectively. Risk perception and comprehensive knowledge towards STH varied significantly across districts and by respondents' educational status. Ownership of improved latrine was associated to comprehensive knowledge of STH. The STH preventive practice that varied across districts was predicted by the overall and knowledge specific to washing hands at critical times. The practice of washing hands at critical times was significantly associated to knowledge of hand washing, owning improved latrine, and age from 15 to 34 year compared to >45 year. Moreover, qualitative findings were supportive of the findings.

CONCLUSION

Despite reported exposures to STH communication opportunities, the study found modest levels of knowledge, perceptions, and preventive practices related to STH among rural communities where the burden of STH was the programmatic concern. These levels of knowledge, perceptions, and practices varied across the districts. Educational and latrine status predicted overall knowledge, whereas knowledge specific to hand washing and overall knowledge were predictors of STH preventive practice. Furthermore, washing hands during critical times was moderately improved among the young-aged, ownership of improved latrine and knowledgeable on hand washing. This study underscores the need for locally tailored and contextualized community behavioral change interventions needs to be strengthened toward improved STH preventive practices.

Epidemiology of malaria, schistosomiasis, and geohelminthiasis amongst children 3-15 years of age during the dry season in Northern Cameroon

BACKGROUND

The double burden of malaria and helminthiasis in children poses an obvious public health challenge, particularly in terms of anemia morbidity. While both diseases frequently geographically overlap, most studies focus on mono-infection and general prevalence surveys without molecular analysis. The current study investigated the epidemiological determinants of malaria, schistosomiasis, and geohelminthiasis transmission among children in the North Region of Cameroon.

METHODOLOGY

School and pre-school children aged 3-15 year-of-age were enrolled from three communities in March 2021 using a community cross-sectional design. Capillary-blood samples were obtained, and each was examined for malaria parasites using rapid-diagnostic-test (RDT), microscopy, and PCR while hemoglobin level was measured using a hemoglobinometer. Stool samples were analyzed for Schistosoma mansoni, S. guineensis, and soil-transmitted-helminthiasis (STH) infections using the Kato Katz method, and urine samples were assessed for the presence of S. haematobium eggs (including hybrids) using the standard urine filtration technique.

RESULT

A malaria prevalence of 56% (277/495) was recorded by PCR as opposed to 31.5% (156/495) by microscopy and 37.8% (186/495) by RDT. Similarly, schistosomiasis was observed at prevalence levels of up to 13.3% (66/495) overall [S. haematobium (8.7%); S. mansoni (3.8%); mixed Sh/Sm (0.6%); mixed Sh/Sm/Sg (0.2%). Both infections were higher in males and the 3-9 year-of-age groups. A high frequency of PCR reported P. falciparum mono-infection of 81.9% (227/277) and mixed P. falciparum/P. malariae infection of 17.3% (48/277) was observed. Malaria-helminths co-infections were observed at 13.1% (65/495) with marked variation between P. falciparum/S. haematobium (50.8%, 33/65); P. falciparum/S. mansoni (16.9%, 11/65) and P. falciparum/Ascaris (9.2%, 6/65) (χ2 = 17.5, p = 0.00003). Anemia prevalence was 32.9% (163/495), categorically associated with P. falciparum (45.8%, 104/227), Pf/Sh (11.5%, 26/227), and Pf/Sm (3.9%, 9/227) polyparasitism.

CONCLUSION

Polyparasitism with malaria and helminth infections is common in school-aged children despite periodic long-lasting insecticide-treated nets (LLINs) distribution and regular school-based praziquantel (for schistosomiasis) and albendazole (for STH) campaigns. Co-existence of Plasmodium parasites and helminths infections notably Schistosoma species among children may concurrently lead to an increase in Plasmodium infection with an enhanced risk of anemia, highlighting the necessity of an integrated approach for disease control interventions.

Behaviour change interventions for the control and elimination of schistosomiasis: A systematic review of evidence from low- and middle-income countries

BACKGROUND

For the last two decades, schistosomiasis control efforts have focussed on preventive treatment. The disease, however, still affects over 200 million people worldwide. Behaviour change (BC) interventions can strengthen control by interrupting transmission through modifying exposure behaviour (water contact) or transmission practices (open urination/defaecation); or through fostering treatment seeking or acceptance. This review examines these interventions to assess their effectiveness in modifying risk practices and affecting epidemiological trends.

METHODOLOGY/PRINCIPAL FINDINGS

A systematic multi-database literature search (PROSPERO CRD42021252368) was conducted for peer-reviewed publications released at any time before June 2021 assessing BC interventions for schistosomiasis control in low- and middle-income countries. 2,593 unique abstracts were identified, 66 were assigned to full text review, and 32 met all inclusion criteria. A typology of intervention models was outlined according to their use of behaviour change techniques and overarching rationale: health education (HEIs), social-environmental (SEIs), physical-environmental (PEIs), and incentives-centred interventions (ICIs). Available evidence does not allow to identify which BC approach is most effective in controlling risk behaviour to prevent schistosomiasis transmission. HEIs' impacts were observed to be limited by structural considerations, like infrastructure underdevelopment, economic obligations, socio-cultural traditions, and the natural environment. SEIs may address those challenges through participatory planning and implementation activities, which enable social structures, like governance and norms, to support BC. Their effects, however, appear context-sensitive. The importance of infrastructure investments was highlighted by intervention models. To adequately support BC, however, they require users' inputs and complementary services. Whilst ICIs reported positive impacts on treatment uptake, there are cost-effectiveness and sustainability concerns. Evaluation studies yielded limited evidence of independent epidemiological impacts from BC, due to limited use of suitable indicators and comparators. There was indicative evidence, however, that BC projects could sustain gains through treatment campaigns.

CONCLUSIONS/SIGNIFICANCE

There is a need for integrated interventions combining information provision, community-based planning, and infrastructure investments to support BC for schistosomiasis control. Programmes should carefully assess local conditions before implementation and consider that long-term support is likely needed. Available evidence indicates that BC interventions may contribute towards schistosomiasis control when accompanied by treatment activities. Further methodologically robust evidence is needed to ascertain the direct epidemiological benefits of BC.

Water, sanitation and schistosomiasis mansoni: a study based on the Brazilian National Prevalence Survey (2011-2015)

This study aimed to explore the association between water, sanitation, and the prevalence of schistosomiasis mansoni in students aged 7 to 17 years from all 27 federative units in Brazil. It was a cross-sectional study conducted based on data on the prevalence of schistosomiasis mansoni referring to 197,567 students from 521 Brazilian municipalities, who participated in the National Survey on the Prevalence of Schistosomiasis Mansoni and Soil-transmitted Helminth Infections (2011-2015). Univariable and multivariable generalized linear models of the negative binomial type were adjusted using 25 and 5% significance levels, respectively, considering municipalities as the unit of analysis. While a protective association was found between access to filtered water in schools and schistosomiasis mansoni prevalence, sanitation in schools was indicated as a risk factor. The collection of wastewater through a network is not universal in Brazil, and even when present, it is not necessarily carried out by the treatment of collected effluents, thus often resulting in the direct discharge of raw sewage into water resources. Regarding septic tanks, only the presence of infrastructure alone does not guarantee its correct use by the population.

Novel tools and strategies for breaking schistosomiasis transmission: study protocol for an intervention study

Background

Global elimination of schistosomiasis as a public health problem is set as target in the new World Health Organization’s Neglected Tropical Diseases Roadmap for 2030. Due to a long history of interventions, the Zanzibar islands of Tanzania have reached this goal since 2017. However, challenges occur on the last mile towards interruption of transmission. Our study will investigate new tools and strategies for breaking schistosomiasis transmission.

Methods

The study is designed as an intervention study, documented through repeated cross-sectional surveys (2020–2024). The primary endpoint will be the sensitivity of a surveillance-response approach to detect and react to outbreaks of urogenital schistosomiasis over three years of implementation. The surveys and multi-disciplinary interventions will be implemented in 20 communities in the north of Pemba island. In low-prevalence areas, surveillance-response will consist of active, passive and reactive case detection, treatment of positive individuals, and focal snail control. In hotspot areas, mass drug administration, snail control and behaviour change interventions will be implemented. Parasitological cross-sectional surveys in 20 communities and their main primary schools will serve to adapt the intervention approach annually and to monitor the performance of the surveillance-response approach and impact of interventions. Schistosoma haematobium infections will be diagnosed using reagent strips and urine filtration microscopy, and by exploring novel point-of-care diagnostic tests.

Discussion

Our study will shed light on the field applicability and performance of novel adaptive intervention strategies, and standard and new diagnostic tools for schistosomiasis elimination. The evidence and experiences generated by micro-mapping of S. haematobium infections at community level, micro-targeting of new adaptive intervention approaches, and application of novel diagnostic tools can guide future strategic plans for schistosomiasis elimination in Zanzibar and inform other countries aiming for interruption of transmission.

Trial registration ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493

Evaluation of a urogenital schistosomiasis behavioural intervention among students from rural schools in Unguja and Pemba islands, Zanzibar

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Children self-reported changes in urogenital schistosomiasis risk taking behaviours.

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Children self-reported an increase in swallowing anthelmintic drugs during MDA.

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Rebranding the concept of “worm” to “blood fluke” created a critical perceived health threat.

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The Health Belief Model was a viable foundation for the behavioural intervention.

Urogenital schistosomiasis is a common experience among children in Zanzibar. There is a paucity of behavioural science-based, health education and behaviour change (HEBC) interventions for school-aged children, those at greatest risk for urogenital schistosomiasis. We assessed the influence of a HEBC intervention, guided by the Health Belief model, among rural schoolchildren on Pemba and Unguja islands in Zanzibar, Tanzania. From 2012 to 2016, a cluster-randomized trial to assess three different interventions against urogenital schistosomiasis was conducted in 90 schools and shehias across Zanzibar. The HEBC intervention was implemented in 15 schools per island. In 2017, at the trial conclusion, we administered written questionnaires to schoolchildren from 4 HEBC intervention schools and 4 not HEBC exposed schools on each island, respectively. Responses were compared between students that were exposed or not exposed to the HEBC intervention using a Fisher's exact test. A total of 1451 students, 708 from intervention and 743 from non-intervention schools completed the questionnaire. Noting some between island differences, students who had received the HEBC interventions reported significant improvements in knowledge about Schistosoma haematobium transmission and personal risk, strategies for schistosomiasis prevention, and self-reported changes in risk behaviours: stopped washing laundry/dishes 49.4% (350/708) versus 5.8% (43/743), stopped bathing in streams/ponds 49.4% (350/708) versus 4.2% (31/743), and stopped playing in streams/ponds 40.8% (289/708) versus 10.8% (80/743). HEBC exposed children also reported a significant increase in swallowing tablets during mass drug administration (MDA) campaigns (when they had not before) 30.2% (214/708) versus 4.6% (34/743). The school based HEBC interventions were associated with desirable positive behaviour change among students. Data suggest that scaling up HEBC interventions to all schools in high-risk areas, augmented with bi-annual MDA, can help to reduce prevalence of urogenital schistosomiasis in Zanzibar, strengthening the possibility for future disease elimination.

Schistosomiasis with a Focus on Africa

Schistosomiasis is a common neglected tropical disease of impoverished people and livestock in many developing countries in tropical Africa, the Middle East, Asia, and Latin America. Substantial progress has been made in controlling schistosomiasis in some African countries, but the disease still prevails in most parts of sub-Saharan Africa with an estimated 800 million people at risk of infection. Current control strategies rely primarily on treatment with praziquantel, as no vaccine is available; however, treatment alone does not prevent reinfection. There has been emphasis on the use of integrated approaches in the control and elimination of the disease in recent years with the development of health infrastructure and health education. However, there is a need to evaluate the present status of African schistosomiasis, primarily caused by Schistosoma mansoni and S. haematobium, and the factors affecting the disease as the basis for developing more effective control and elimination strategies in the future. This review provides an historical perspective of schistosomiasis in Africa and discusses the current status of control efforts in those countries where the disease is endemic.

Factors influencing uptake of schistosomiasis research findings in ingwavuma area, uMkhanyakude District, Kwazulu-Natal, South Africa

Background

Research uptake is concerned with spreading ideas across multiple levels of the community. Barriers such as poverty, lack of infrastructure, illiteracy and culture prevent information sharing in arid rural areas of sub-Saharan Africa.

Objective

This study explores the factors influencing schistosomiasis research uptake and the available channels for the uptake of research findings from a transdisciplinary and eco-health research project on schistosomiasis in Ingwavuma area, uMkhanyakude district, KwaZulu-Natal province in South Africa.

Methods

This case study conducted in 2017 involved 78 primary school children and 73 heads of household recruited through convenience and purposive sampling. Data were collected through focus group discussions, then transcribed and analysed by the researcher using thematic analysis.

Results

Factors such as poor knowledge, water and sanitation problems, and lack of sufficient health workers hindered the uptake of schistosomiasis research findings. Participants recommended several platforms to share schistosomiasis research findings with the community, including: door to door visits; social gatherings such as sports events, talent shows, and religious gatherings; mass media platforms such as radio and television; social media platforms such as WhatsApp, Facebook and Twitter; and printed media such as posters, booklets and pamphlets.

Conclusions

There is a need to train health workers and peer educators in this area of South Africa to educate people about schistosomiasis infection, screening and treatment through home visits or social events. Schistosomiasis research findings must be synthesised and packaged in different forms for dissemination via multimedia media-based communication channels.

The epidemiological status of urogenital schistosomiasis among reproductive aged individuals in the Tiko Health Area- a semi-urban setting in the Mount Cameroon area

BACKGROUND

Urogenital schistosomiasis (UGS) caused by S. haematobium has enormous reproductive health consequences including infertility. Reproductive aged individuals are a neglected group and not included in control programs in Cameroon. This study investigated the prevalence and severity of S. haematobium infection in the context of gender and socio-economic structures that shape behaviour among reproductive aged individuals living in Tiko, a semi-urban setting, Cameroon.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study was carried out in the Tiko Health District (THD) between May to September 2019. Consenting individuals were enrolled using a convenient sampling technique and administered a semi-structured questionnaire to document data on socio-demographic and stream contact behaviour. A urine sample was collected and screened for the presence of S. haematobium ova using reagent strips, filtration and microscopy. The overall prevalence of S. haematobium infection was 22.8% (95% CL: 19.27-26.73) with geometric mean egg load of 18.74 (range: 1-1600) per 10ml of urine. Younger age group (15 - 20years) (OR: 5.13; 95% CL: 1.35-19.42), male (OR: 2.60 3.07; 95% CL: 1.54-4.40) and awareness of UGS (OR: 1.73; 95% CL: 1.02-2.95) were associated with higher odds of exposure to infection. Significantly higher intensity of infection was seen in males, singles and in the age group 15-30 years. It is worth noting that males carried out more activities which entailed longer duration in streams.

CONCLUSION/SIGNIFICANCE

The prevalence obtained shows that Tiko is a moderate-risk area for UGS with underlying morbidity-inducing infection intensity. The severity of the infection is more in males. Awareness of the disease is not enough to protect these communities from infection, but provision of public infrastructures and health education will limit contact with infested water and thus curtail the infection. There is an urgent need to involve all age groups in control programs.

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.

Core components, concepts and strategies for parasitic and vector-borne disease elimination with a focus on schistosomiasis: A landscape analysis

Efforts to control and eliminate human schistosomiasis have accelerated over the past decade. In a number of endemic countries and settings, interruption of schistosome transmission has been achieved. In others, Schistosoma infections continue to challenge program managers at different levels, from the complexity of the transmission cycle, over limited treatment options and lack of field-friendly accurate diagnostics, to controversy around adequate intervention strategies. We conducted a landscape analysis on parasitic and vector-borne disease elimination approaches with the aim to identify evidence-based strategies, core components and key concepts for achieving and sustaining schistosomiasis control and for progressing elimination efforts towards interruption of transmission in sub-Saharan Africa. A total of 118 relevant publications were identified from Web of Science, Pubmed and the grey literature and reviewed for their content. In addition, we conducted in-depth interviews with 23 epidemiologists, program managers, policymakers, donors and field researchers. Available evidence emphasizes the need for comprehensive, multipronged and long-term strategies consisting of multiple complementary interventions that must be sustained over time by political commitment and adequate funding in order to reach interruption of transmission. Based on the findings of this landscape analysis, we propose a comprehensive set of intervention strategies for schistosomiasis control and elimination. Before deployment, the proposed interventions will require review, evaluation and validation in the frame of an expert consultation as a step towards adaptation to specific contexts, conditions and settings. Field testing to ensure local relevance and effectiveness is paramount given the diversity of socio-ecological and epidemiological contexts.

This landscape analysis explored successful concepts, approaches and interventions of past and ongoing parasitic and vector-borne disease elimination efforts and programs with regard to relevance for progress in the elimination of human schistosome infections. Schistosomiasis is a disabling, water borne parasitic disease of public health concern with an estimated 250 million people infected worldwide. The long-term morbidity of this neglected tropical disease significantly impacts growth, cognition and socioeconomic development at all ages. Despite increased global efforts to control morbidity and advance elimination, challenges in view of the complex life cycle which involves freshwater sources, intermediate snail hosts and humans, remain. This calls for targeted interventions and concerted programs. According to the evidence from the literature and as proposed by a wide range of key informants, comprehensive, multipronged and long-term strategies supported by strong political commitment and adequate funding are required in order to achieve and sustain the set goals. Based on the findings, we propose here a comprehensive set of intervention strategies for schistosomiasis control and elimination for review and evaluation to inform implementation research needs and elimination program design.

T. F, Olusi TA. Will Nigerians Win the War Against Urinary Schistosomiasis? Prevalence, Intensity, Risk Factors and Knowledge Assessment among Some Rural Communities in Southwestern Nigeria

Urinary schistosomiasis is a devastating parasitic disease in Nigeria. This study was carried out to investigate the current prevalence, intensity, risk factors and knowledge assessment among some rural communities in southwestern Nigeria. A cross-sectional study was carried out in which a standard urine filtrations technique was used to determine the prevalence and intensity of infection. A well-designed questionnaire was used to collect subject's data on demographic and socioeconomic characteristics. Of the total 620 urine samples examined, overall 346 (55.81%) were positive with a mean egg intensity (S.D) of 65.60 (59.33) egg/10 mL of urine. Significant differences occurred in the analysis. Males had the highest prevalence and intensity of 224 (61.9%) and 69.20 egg/10 mL of urine, respectively. The 10-14 years age group had the highest prevalence of 65.9% while mean intensity of infection among the age group decreases with increasing age, with the highest mean intensity of infection (80.14 egg/10 mL) recorded among the age group ≤ 4 years. Bivariate logistic regression analysis showed that being age group 10-14 (COR 0.27, 95% CI: 0.09-0.79) and dependent on river (COR 0.67, 95% CI: 0.33-1.33) increased the odd of contracting an infection. Similarly, the knowledge of respondents on urinary schistosomiasis was low. Conclusively, urinary schistosomiasis is still persistent at a very high rate in the study area and appropriate control measure should be deployed.

Gender-related factors affecting health seeking for neglected tropical diseases: findings from a qualitative study in Ethiopia

BACKGROUND

Despite known gender-specific differences in terms of prevalence, transmission and exposure to neglected tropical diseases (NTDs), there is limited discussion of the influence of gender in NTD programmes and interventions. There is a paucity of research on how gender interacts with NTD service provision and uptake. This study, part of broader implementation research in Ethiopia, applied a gender lens to health seeking for five NTDs: lymphatic filariasis, podoconiosis, schistosomiasis, soil-transmitted helminth infection and trachoma.

METHODOLOGY/PRINCIPAL FINDINGS

The study was conducted in a district of the Southern Nations, Nationalities, and Peoples' Region of Ethiopia where the five NTDs are prevalent. A qualitative methodology was adopted to explore participants' perspectives and experiences. Data generation methods included 20 interviews and four focus group discussions. Community members, volunteer Health Development Army leaders, Health Extension Workers and a range of health workers at the health post, health centre and hospital level (n = 59) were purposively sampled. Interviews and focus group discussions were audio recorded, transcribed verbatim into English then analysed through open coding, drawing on constant comparative methods. Gender related factors affected care seeking for NTDs and were described as reasons for not seeking care, delayed care seeking and treating NTDs with natural remedies. Women faced additional challenges in seeking health care due to gender inequalities and power dynamics in their domestic partnerships. Participants recommended raising community awareness about NTDs, however this remains problematic due to gender and social norms around appropriate discourse with members of the opposite gender.

CONCLUSIONS/SIGNIFICANCE

The findings from this study provide crucial insights into how gender interacts with accessing health services, at different levels of the health system. If we are committed to leaving no one behind and achieving universal health coverage, it is essential to address gender disparities to access and utilisation of interventions delivered by national NTD programmes.

Prevalence and Risk Factors for Schistosomiasis among Schoolchildren in two Settings of Côte d'Ivoire

Schistosomiasis is a parasitic disease affecting more than 250 million people, primarily in sub-Saharan Africa. In Côte d’Ivoire both Schistosoma haematobium (causing urogenital schistosomiasis) and Schistosoma mansoni (causing intestinal schistosomiasis) co-exist. This study aimed to determine the prevalence of S. haematobium and S. mansoni and to identify risk factors among schoolchildren in the western and southern parts of Côte d’Ivoire. From January to April 2018, a cross-sectional study was carried out including 1187 schoolchildren aged 5–14 years. Urine samples were examined by a filtration method to identify and count S. haematobium eggs, while stool samples were subjected to duplicate Kato-Katz thick smears to quantify eggs of S.mansoni and soil-transmitted helminths. Data on sociodemographic, socioeconomic, and environmental factors were obtained using a pretested questionnaire. Multivariate logistic regression was employed to test for associations between variables. We found a prevalence of S. haematobium of 14.0% (166 of 1187 schoolchildren infected) and a prevalence of S. mansoni of 6.1% (66 of 1089 schoolchildren infected). In the southern part of Côte d’Ivoire, the prevalence of S. haematobium was 16.1% with a particularly high prevalence observed in Sikensi (35.6%), while S. mansoni was most prevalent in Agboville (11.2%). Swimming in open freshwater bodies was the main risk factor for S. haematobium infection (adjusted odds ratio (AOR) = 127.0, 95% confidence interval (CI): 25.0–634.0, p < 0.001). Fishing and washing clothes in open freshwater bodies were positively associated with S. haematobium and S. mansoni infection, respectively. Preventive chemotherapy using praziquantel should be combined with setting-specific information, education, and communication strategies in order to change children’s behavior, thus avoiding contact with unprotected open freshwater.

Addressing vulnerability, building resilience: community-based adaptation to vector-borne diseases in the context of global change

Background

The threat of a rapidly changing planet – of coupled social, environmental and climatic change – pose new conceptual and practical challenges in responding to vector-borne diseases. These include non-linear and uncertain spatial-temporal change dynamics associated with climate, animals, land, water, food, settlement, conflict, ecology and human socio-cultural, economic and political-institutional systems. To date, research efforts have been dominated by disease modeling, which has provided limited practical advice to policymakers and practitioners in developing policies and programmes on the ground.

Main body

In this paper, we provide an alternative biosocial perspective grounded in social science insights, drawing upon concepts of vulnerability, resilience, participation and community-based adaptation. Our analysis was informed by a realist review (provided in the Additional file 2) focused on seven major climate-sensitive vector-borne diseases: malaria, schistosomiasis, dengue, leishmaniasis, sleeping sickness, chagas disease, and rift valley fever. Here, we situate our analysis of existing community-based interventions within the context of global change processes and the wider social science literature. We identify and discuss best practices and conceptual principles that should guide future community-based efforts to mitigate human vulnerability to vector-borne diseases. We argue that more focused attention and investments are needed in meaningful public participation, appropriate technologies, the strengthening of health systems, sustainable development, wider institutional changes and attention to the social determinants of health, including the drivers of co-infection.

Conclusion

In order to respond effectively to uncertain future scenarios for vector-borne disease in a changing world, more attention needs to be given to building resilient and equitable systems in the present.

Electronic supplementary material

The online version of this article (doi: 10.1186/s40249-017-0375-2) contains supplementary material, which is available to authorized users.

Risk factors for schistosomiasis transmission among school children in Gwanda district, Zimbabwe

INTRODUCTION

A nationwide cross sectional schistosomiasis survey conducted in 2011 in 280 primary schools found a prevalence rate of 22.7%. This warranted an intervention with Mass Drug Administration at all schools in line with WHO guidelines. This study aimed to identify risk factors for schistosomiasis transmission among Grade 3 children at two primary schools in Gwanda district.

METHODS

A descriptive cross sectional survey which was part of a larger study on Malaria and Bilharzia in Southern Africa (MABISA) was conducted. Grade 3 children (n=120) attending two purposively selected rural primary schools in Dombo and Ntalale in Gwanda were respondents. Data on socio-demographic characteristics and risk factors which included knowledge and practices were collected using a pretested interviewer administered questionnaire.

RESULTS

Of the 120 children, 98 (81.7%) of the children indicated that they did not consistently use the toilet. The other risk factors for schistosomiasis were bathing and swimming in rivers and dams 80 (66.7%), watering the vegetable gardens using unprotected water sources 77 (64.7%) and crossing rivers on their way to school barefooted 31.7%. History of schistosomiasis cases based on self-reporting indicated that of the 9 children 7 were girls. There was poor knowledge of schistosomiasis among the children with 54% of the children indicating that they had never heard about the disease. Misconceptions on the causes of schistosomiasis which included drinking dirty water, mosquitoes and flies as the causes of schistosomiasis were reported by the children. Parents were cited as the least disseminators of information on schistosomiasis with only 4 out of the 120 children having received information from their parents.

CONCLUSION

Frequent contact with unprotected water sources, non-use of the toilet, and lack of information on schistosomiasis could predispose the children to infection. There is need to raise awareness about schistosomiasis in schools and the community to reduce the risk of contracting schistosomiasis due to risky behaviour.

HEALTH EDUCATION AND THE CONTROL OF UROGENITAL SCHISTOSOMIASIS: ASSESSING THE IMPACT OF THE JUMA NA KICHOCHO COMIC-STRIP MEDICAL BOOKLET IN ZANZIBAR

Endeavours to control urogenital schistosomiasis on Unguja Island (Zanzibar) have focused on school-aged children. To assess the impact of an associated health education campaign, the supervised use of the comic-strip medical booklet Juma na Kichocho by Class V pupils attending eighteen primary schools was investigated. A validated knowledge and attitudes questionnaire was completed at baseline and repeated one year later following the regular use of the booklet during the calendar year. A scoring system (ranging from 0.0 to 5.0) measured children's understandings of schistosomiasis and malaria, with the latter being a neutral comparator against specific changes for schistosomiasis. In 2006, the average score from 751 children (328 boys and 423 girls) was 2.39 for schistosomiasis and 3.03 for malaria. One year later, the score was 2.43 for schistosomiasis and 2.70 for malaria from 779 children (351 boys and 428 girls). As might be expected, knowledge and attitudes scores for schistosomiasis increased (+0.05), but not as much as originally hoped, while the score for malaria decreased (-0.33). According to a Kolmogorov-Smirnov test, neither change was statistically significant. Analysis also revealed that 75% of school children misunderstood the importance of reinfection after treatment with praziquantel. These results are disappointing. They demonstrate that it is mistaken to assume that knowledge conveyed in child-friendly booklets will necessarily be interpreted, and acted upon, in the way intended. If long-term sustained behavioural change is to be achieved, health education materials need to engage more closely with local understandings and responses to urogenital schistosomiasis. This, in turn, needs to be part of the development of a more holistic, biosocial approach to the control of schistosomiasis.

Development and testing of Schisto and Ladders™, an innovative health educational game for control of schistosomiasis in schoolchildren

Background

Schistosomiasis remains a public health problem in many regions of the world, including Nigeria. Current control strategy involves mass drug administration with praziquantel to the endemic population. To complement and sustain on-going preventive chemotherapy, we developed a health educational game named Schisto and Ladders™ and tested its potential for the control of schistosomiasis among schoolchildren living in Imala-Odo, a highly endemic community near Abeokuta, Nigeria.

Methods

One hundred school children were randomly selected and divided into intervention and control groups through balloting. Their knowledge, attitudes and practices (KAP) concerning schistosomiasis transmission, control and prevention were assessed using structured questionnaires. Schisto and Ladders™ game were given to the intervention group and the popular Snake and Ladders™ game to the control group. Both games were played for 2 months under the supervision of their class teachers. A post-KAP assessment was carried out in both groups, including focus group discussions (FGDs) to investigate knowledge and the impact of the games.

Results

Knowledge about urinary schistosomiasis and its transmission significantly improved (P = 0.000) in the intervention group (68.0%) compared to the control group (8.0%). FGDs showed that the frequency of visits to dam water also significantly reduced (P = 0.048) in the intervention group (18.0%) compared to the control group (40.0%). There was a significant increase in knowledge regarding risk behaviours, prevention and control of schistosomiasis among the intervention group, but no new knowledge gained in the control group.

Conclusions

This study demonstrates the potential of the health education game Schisto and Ladders™ for teaching basic health education and promoting behavioural changes among schoolchildren in endemic communities.

Dynamics of freshwater snails and Schistosoma infection prevalence in schoolchildren during the construction and operation of a multipurpose dam in central Côte d'Ivoire

Background

The construction and operation of small multipurpose dams in Africa have a history of altering the transmission of water-based diseases, including schistosomiasis. The current study was designed to investigate the abundance and dynamics of schistosomiasis intermediate host snails and Schistosoma infections in humans during the construction and the first years of operation of a small multipurpose dam in Côte d’Ivoire.

Methods

The study was carried out in Raffierkro and four neighbouring villages in central Côte d’Ivoire between 2007 and 2012. Snails were collected by two experienced investigators using scoops and forceps for 15 min at each site. Snails were identified at genera and, whenever possible, species level, and subjected to testing for cercarial shedding. Schoolchildren aged 6–15 years were examined once every year for Schistosoma haematobium and S. mansoni infection, using urine filtration and duplication Kato-Katz thick smears, respectively. Additionally, 551 adults were examined for Schistosoma infection before (June 2007) and 359 individuals 2 years after dam construction (June 2009).

Results

Overall, 1 700 snails belonging to nine different genera were collected from 19 sampling sites. Bulinus (potential intermediate host snails of S. haematobium) and Pila were the most common genera, whereas Biomphalaria (potential intermediate host snail of S. mansoni), Lymnaea, Physa and Melanoides were found in two villages. During the first-year sampling period, 65 snails were collected, of which 13 (20%) were schistosomiasis intermediate hosts. In subsequent years, out of 1 635 snails collected, 1 079 (66%) were identified as potential intermediate host for schistosomiasis, but none were shedding cercariae. The prevalence of S. mansoni among adults in the study area was low (0.4% in 2007 and 0.3% in 2009), whereas the prevalence of S. haematobium declined from 13.9% to 2.9% in this two-year period.

Conclusions

The low prevalence of schistosomiasis in humans and the absence of infected intermediate host snails during the construction and early phase of operation of a small multipurpose dam suggest that there was no or only very little local transmission. However, the considerable increase in the number of intermediate host snails and their dispersion in irrigation canals call for rigorous surveillance, so that adequate public health measures can be taken in case of early signs of an outbreak.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0305-3) contains supplementary material, which is available to authorized users.

Knowledge, practices and perceptions of geo-helminthes infection among parents of pre-school age children of coastal region, Kenya

BACKGROUND

Soil-transmitted helminthes (STHs) are common human parasitic diseases in most of the developing world particularly in Kenya. The ongoing National School-Based Deworming Programme (NSBDP) was launched in 2012 and is currently targeting 28 of the 47 endemic Counties. In an effort to improve treatment intervention strategies among Pre-School Age Children (PSAC) attending Early Childhood Development Centres (ECDC), we sought to assess parents' knowledge, perceptions and practices on worm infection.

METHODOLOGY

We conducted a qualitative cross-sectional study in four endemic sub-counties of two counties of coastal region of Kenya. A total of 20 focus group discussions (FGDs) categorized by gender were conducted among parents of pre-school age children. Participants were purposively selected based on homogenous characteristics with the saturation model determining the number of focus group discussions conducted. The data collected was analyzed manually by study themes.

FINDINGS

The majority of the parents had knowledge on worms and modes of transmission of the parasitic infections among the pre-school children. Also, most of the participants knew the causes of worm infection and the pre- disposing factors mentioned included poor hygiene and sanitation practices. Due to poor knowledge of signs and symptoms, misconceptions about the drugs administered during the NSBDP were common with a large majority of the parents indicating that the drugs were ineffective in worm control. The findings also indicated that most of the participants sought medical care on the onset of the signs and symptoms of worm infestation and preferred services provided at public health facilities as opposed to private health facilities or buying drugs from the local market citing mistrust of such services. Cultural beliefs, high cost of building and availability of vast pieces of land for human waste disposal were factors that contributed to low or lack of latrine ownership and usage by a large majority of the respondents.

CONCLUSIONS

Our results show that to a large extent the parents of the pre-school age children have information on worm infections. However, some cultural beliefs and practices on the pathology and mode of transmission mentioned could be a hindrance to prevention and control efforts. There is need to implement health promotion campaigns to strengthen the impact of control strategies and reduce infection.

Community Knowledge, Perceptions, and Practices Associated with Urogenital Schistosomiasis among School-Aged Children in Zanzibar, United Republic of Tanzania

BACKGROUND

On the Zanzibar islands, United Republic of Tanzania, elimination of urogenital schistosomiasis is strived for in the coming years. This qualitative study aimed to better understand community knowledge, perceptions, and practices associated with schistosomiasis among school-aged children on Unguja and Pemba islands, in order to inform the development of behavior change interventions contributing to eliminate urogenital schistosomiasis.

METHODOLOGY

In 2011, we conducted 35 children's discussion groups, 41 in-depth interviews with parents and teachers, and 5 focus group discussions with community members in Zanzibar. Using a modified-grounded theory approach, we transcribed and coded the narrative data followed by thematic analysis of the emergent themes.

PRINCIPAL FINDINGS

Urogenital schistosomiasis is a common experience among children in Zanzibar and typically considered a boys' disease. Children engage in multiple high-risk behaviors for acquiring schistosomiasis because of poor knowledge on disease transmission, lack of understanding on severity of disease-associated consequences, and lack of alternative options for water related activities of daily living and recreational play. Local primary school teachers had little to no training about the disease and no teaching tools or materials for students.

CONCLUSIONS/SIGNIFICANCE

Conducting activities in open natural freshwater contaminated by S. haematobium larvae compromises the health of school-aged children in Zanzibar. The perception of urogenital schistosomiasis as a minor illness rather than a serious threat to a child's well-being contributes to the spread of disease. Understanding community perceptions of disease along with the barriers and facilitators to risk reduction behaviors among children can inform health promotion activities, campaigns, and programs for the prevention, control, and elimination of urogenital schistosomiasis in Zanzibar.

Gaining and sustaining schistosomiasis control: study protocol and baseline data prior to different treatment strategies in five African countries

BACKGROUND

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study.

METHODS

Beginning in 2009, SCORE held a series of meetings to specify empirical questions and design studies related to different schedules of PCT for schistosomiasis control in communities with high (gaining control studies) and moderate (sustaining control studies) prevalence of Schistosoma infection among school-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention strategies.

RESULTS

These studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control.

CONCLUSIONS

We expect that the study outcomes will provide data for decision-making for country programme managers and a rich resource of information to the schistosomiasis research community.

TRIAL REGISTRATION

The trials are registered at International Standard Randomised Controlled Trial registry (identifiers: ISRCTN99401114 , ISRCTN14849830 , ISRCTN16755535 , ISRCTN14117624 , ISRCTN95819193 and ISRCTN32045736 ).

A mixed-methods approach to understanding water use and water infrastructure in a schistosomiasis-endemic community: case study of Asamama, Ghana

Background

Surface water contaminated with human waste may transmit urogenital schistosomiasis (UGS). Water-related activities that allow skin exposure place people at risk, but public health practitioners know little about why some communities with access to improved water infrastructure have substantial surface water contact with infectious water bodies. Community-based mixed-methods research can provide critical information about water use and water infrastructure improvements.

Methods

Our mixed-methods study assessed the context of water use in a rural community endemic for schistosomiasis.

Results

Eighty-seven (35.2 %) households reported using river water but not borehole water; 26 (10.5 %) reported using borehole water but not river water; and 133 (53.8 %) households reported using both water sources. All households are within 1 km of borehole wells, but tested water quality was poor in most wells. Schistosomiasis is perceived by study households (89.3 %) to be a widespread problem in the community, but perceived schistosomiasis risk fails to deter households from river water usage. Hematuria prevalence among schoolchildren does not differ by household water use preference. Focus group data provides context for water preferences. Demand for improvements to water infrastructure was a persistent theme; however, roles and responsibilities with respect to addressing community water and health concerns are ill-defined.

Conclusions

Collectively, our study illustrates how complex attitudes towards water resources can affect which methods will be appropriate to address schistosomiasis.

China-Africa and China-Asia Collaboration on Schistosomiasis Control: A SWOT Analysis

Schistosomiasis, a disease caused by a trematode, parasitic worm, is a worldwide public health problem. In spite of great progress with regard to morbidity control, even elimination of this infection in recent decades, there are still challenges to overcome in sub-Saharan Africa and endemic areas in Southeast Asia. Regarded as one of the most successful countries with respect to schistosomiasis control, The People's Republic of China has accumulated considerable experience and learnt important lessons in various local settings that could benefit schistosomiasis control in other endemic countries. Based on an analysis of conceived strengths, weaknesses, opportunities and threats (SWOT) of potential collaborative activities with regard to schistosomiasis in Africa and Asia, this article addresses the importance of collaborative efforts and explores the priorities that would be expected to facilitate the transfer of Chinese experience to low- and middle-income countries in Africa and Asia.

CONTROL OF SCHISTOSOMIASIS IN THE GEZIRA IRRIGATION SCHEME, SUDAN

This paper analyses the changing patterns of infection with Schistosoma mansoni and S. haematobium in the Gezira Irrigation Scheme, Sudan. Taking a historical perspective, it shows the way in which factors such as ecology, biology, social and economic variables and politics have shaped patterns of infection, and how different kinds of strategies have been developed to control schistosomal infection over time. Wider political and economic issues at both national and international levels have shaped these strategies, influencing the prevalence and intensity of schistosomal infection at a local level. By highlighting the inter-play between the above-mentioned factors, the article reflects on the wisdom of prioritizing community-directed mass drug administration for the control of schistosomiasis in Gezira and elsewhere. The review demonstrates that not all efforts to control schistosomiasis are sustainable. A comprehensive control strategy involving political commitment, community participation and socioeconomic development is important for sustainable control of schistosomal infection.

Improved Perceptions and Practices Related to Schistosomiasis and Intestinal Worm Infections Following PHAST Intervention on Kome Island, North-Western Tanzania

Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ≥15 years. We found significant increases in respondents’ knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents’ knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections.

Spatial distribution of schistosomiasis and treatment needs in sub-Saharan Africa: a systematic review and geostatistical analysis

BACKGROUND

Schistosomiasis affects more than 200 million individuals, mostly in sub-Saharan Africa, but empirical estimates of the disease burden in this region are unavailable. We used geostatistical modelling to produce high-resolution risk estimates of infection with Schistosoma spp and of the number of doses of praziquantel treatment needed to prevent morbidity at different administrative levels in 44 countries.

METHODS

We did a systematic review to identify surveys including schistosomiasis prevalence data in sub-Saharan Africa via PubMed, ISI Web of Science, and African Journals Online, from inception to May 2, 2014, with no restriction of language, survey date, or study design. We used Bayesian geostatistical meta-analysis and rigorous variable selection to predict infection risk over a grid of 1 155 818 pixels at 5 × 5 km, on the basis of environmental and socioeconomic predictors and to calculate the number of doses of praziquantel needed for prevention of morbidity.

FINDINGS

The literature search identified Schistosoma haematobium and Schistosoma mansoni surveys done in, respectively, 9318 and 9140 unique locations. Infection risk decreased from 2000 onwards, yet estimates suggest that 163 million (95% Bayesian credible interval [CrI] 155 million to 172 million; 18·5%, 17·6-19·5) of the sub-Saharan African population was infected in 2012. Mozambique had the highest prevalence of schistosomiasis in school-aged children (52·8%, 95% CrI 48·7-57·8). Low-risk countries (prevalence among school-aged children lower than 10%) included Burundi, Equatorial Guinea, Eritrea, and Rwanda. The numbers of doses of praziquantel needed per year were estimated to be 123 million (95% CrI 121 million to 125 million) for school-aged children and 247 million (239 million to 256 million) for the entire population.

INTERPRETATION

Our results will inform policy makers about the number of treatments needed at different levels and will guide the spatial targeting of schistosomiasis control interventions.

FUNDING

European Research Council, China Scholarship Council, UBS Optimus Foundation, and Swiss National Science Foundation.

Risk profiling of schistosomiasis using remote sensing: approaches, challenges and outlook

BACKGROUND

Schistosomiasis is a water-based disease that affects an estimated 250 million people, mainly in sub-Saharan Africa. The transmission of schistosomiasis is spatially and temporally restricted to freshwater bodies that contain schistosome cercariae released from specific snails that act as intermediate hosts. Our objective was to assess the contribution of remote sensing applications and to identify remaining challenges in its optimal application for schistosomiasis risk profiling in order to support public health authorities to better target control interventions.

METHODS

We reviewed the literature (i) to deepen our understanding of the ecology and the epidemiology of schistosomiasis, placing particular emphasis on remote sensing; and (ii) to fill an identified gap, namely interdisciplinary research that bridges different strands of scientific inquiry to enhance spatially explicit risk profiling. As a first step, we reviewed key factors that govern schistosomiasis risk. Secondly, we examined remote sensing data and variables that have been used for risk profiling of schistosomiasis. Thirdly, the linkage between the ecological consequence of environmental conditions and the respective measure of remote sensing data were synthesised.

RESULTS

We found that the potential of remote sensing data for spatial risk profiling of schistosomiasis is - in principle - far greater than explored thus far. Importantly though, the application of remote sensing data requires a tailored approach that must be optimised by selecting specific remote sensing variables, considering the appropriate scale of observation and modelling within ecozones. Interestingly, prior studies that linked prevalence of Schistosoma infection to remotely sensed data did not reflect that there is a spatial gap between the parasite and intermediate host snail habitats where disease transmission occurs, and the location (community or school) where prevalence measures are usually derived from.

CONCLUSIONS

Our findings imply that the potential of remote sensing data for risk profiling of schistosomiasis and other neglected tropical diseases has yet to be fully exploited.

Community perceptions, attitude, practices and treatment seeking behaviour for schistosomiasis in L. Victoria islands in Uganda

BACKGROUND

Over 200,000 people, most of them infected with Schistosoma mansoni inhabit 150 islands in Lake Victoria in Uganda. Although a programme to control the disease has been ongoing since 2003, its implementation in islands is inadequate due to high transport costs on water. In 2011 and 2012, the Global Network for Neglected Tropical Diseases (GNNTD) through Schistosomiasis Control Initiative (SCI) provided financial support to ease treatment delivery on the islands and over the period, therapeutic coverage has been increasing. We conducted a study with an objective to assess community awareness of existence of the disease, its signs, symptoms, causes and transmission as well as attitude, practice and health seeking behavior.

METHODS

This was a cross sectional descriptive study which used pre-tested interviewer administered questionnaire among purposively selected individuals in schools, health facilities and communities. Frequency distribution tables, graphs and cross tabulations were the main forms of data presentation.

RESULTS

Our results showed that there are numerous challenges that must be overcome to achieve effective control of schistosomiasis in the islands. Many people especially young men are constantly on the move from island to island in search for richer fishing grounds and such groups are commonly known to miss treatment by mass chemotherapy. Unfortunately case management in health facilities is very poor; health facilities are few and understaffed mainly with unskilled personnel who are overburdened by other illnesses such as malaria and HIV and the supply of praziquantel in health facilities is inadequate. Furthermore, sanitation is appalling, no clean water and community knowledge about schistosomiasis is low even among biomedical staff.

CONCLUSION

Rather than elimination, our results indicate that the programme should continue to target morbidity control beyond the 2020s until preventive measures have been instituted. The government should provide adequate trained health workers and stock praziquantel in all island health facilities.

Global aspirations, local realities: the role of social science research in controlling neglected tropical diseases

Neglected Tropical Diseases (NTDs) are both drivers and manifestations of poverty and social inequality. Increased advocacy efforts since the mid-2000s have led to ambitious new control and elimination targets set for 2020 by the World Health Organisation. While these global aspirations represent significant policy momentum, there are multifaceted challenges in controlling infectious diseases in resource-poor local contexts that need to be acknowledged, understood and engaged. However a number of recent publications have emphasised the “neglected” status of applied social science research on NTDs. In light of the 2020 targets, this paper explores the social science/NTD literature and unpacks some of the ways in which social inquiry can help support effective and sustainable interventions. Five priority areas are discussed, including on policy processes, health systems capacity, compliance and resistance to interventions, education and behaviour change, and community participation. The paper shows that despite the multifaceted value of having anthropological and sociological perspectives integrated into NTD programmes, contemporary efforts underutilise this potential. This is reflective of the dominance of top-down information flows and technocratic approaches in global health. To counter this tendency, social research needs to be more than an afterthought; integrating social inquiry into the planning, monitoring and evaluating process will help ensure that flexibility and adaptability to local realities are built into interventions. More emphasis on social science perspectives can also help link NTD control to broader social determinants of health, especially important given the major social and economic inequalities that continue to underpin transmission in endemic countries.

The effect of a health communication campaign on compliance with mass drug administration for schistosomiasis control in western Kenya--the SCORE project

Compliance with mass drug administration (MDA) can be affected by rumors and mistrust about the drug. Communication campaigns are an effective way to influence attitudes and health behaviors in diverse public health contexts, but there is very little documentation about experiences using health communications in schistosomiasis control programs. A qualitative study was conducted with community health workers (CHWs) as informants to explore the effect of a health communication campaign on their experiences during subsequent praziquantel MDA for schistosomiasis. Discussions were audio-recorded, transcribed verbatim, translated into English where applicable, and analyzed thematically using ATLAS.ti software. According to the CHWs, exposure to mass media messages improved awareness of the MDA, which in turn, led to better treatment compliance. Our findings suggest that communication campaigns influence health behaviors and create awareness of schistosomiasis control interventions, which may ultimately improve praziquantel MDA.

Schistosomiasis transmission; socio-demographic, knowledge and practices as transmission risk factors in pregnant women

Schistosoma transmission is influenced by the interplay between various factors ranging from parasite to host associated factors. While many studies have focused on mass chemotherapy to reduce transmission in other populations, no study has examined the impact of social factors that favour transmission in pregnant women in Nigeria. The study was conducted to assess the impact of knowledge, attitudes and sociodemographic factors on schistosomiasis burden in pregnant women of rural communities of Nigeria. A cross sectional community-based field study was conducted to assess the association between Schistosoma haematobium burden and the associated risk factors among pregnant women in rural endemic communities of Nigeria. Structured questionnaire was used to gather information on participants' socio-demographic data, knowledge on schistosomiasis and water contact activities. Of the 237 respondents examined microscopically for infection, 50 (21.1 %) were infected with overall mean infection intensity of 69.6 ± 165.2 eggs/10 mL urine. Multivariate logistic analysis showed occupation of the women to be associated with infection with the artisans having the highest risk (OR 3.34, CI 1.67-6.69, P = 0.022). Contact with water and water usage patterns are also associated with prevalence of disease with fetching (OR 2.04, CI 0.19-3.51, P = 0.003) and multipurpose water usage (OR 4.31, CI 2.17-8.57, P = 0.0002) being the most predisposing variables respectively. Awareness about water borne diseases showed no association with infection (P = 0.382) with typhoid (23.7 %) and fever (2.6 %) constituting the most and least common water borne diseases mentioned by the women. Health education and provision of good water supply should be integrated into the control strategies in order reduce transmission in endemic areas.

Vesical schistosomiasis with terminal hematuria in sub-Saharan patients

OBJECTIVES

To know the characteristics of vesical schistosomiasis caused by schistosoma hematobium in immigrant patients.

MATERIAL AND METHODS

The retrospective study of 41 cases microbiologically diagnosed in our hospital over the last 16 years is presented. Data was collected on origin, age, presentation form, diagnostic tests and treatment.

RESULTS

All were African patients whose ages ranged from 4 to 32 years and who had terminal macroscopic hematuria. Most of the patients (85%) were men. In all of the cases, diagnosis was by a urinary microbiological study and in one case, cystoscopy with a biopsy of a typical vesical lesion. Terminal hematuria is the most representative clinical sign. They were treated with praziquantel.

CONCLUSIONS

The epidemiology and intermittent terminal hematuria in African patients should lead to the suspicion of vesical schistosomiasis as the first diagnostic option. Urinary microbiological study is a rapid, non-invasive, test with high diagnostic yield that would avoid performing invasive studies. Its simple treatment assures high level of compliance and consequent efficacy.

Health-seeking behaviour for schistosomiasis: a systematic review of qualitative and quantitative literature

Schistosomiasis is a chronic and debilitating parasitic disease acquired through contact with infested freshwater. An essential component of its control is passive case finding, which, in order to be effective, requires a detailed understanding of health-seeking behaviour. This study aimed to systematically review evidence on health-seeking behaviour for schistosomiasis, in order to determine factors influencing use or non-use of modern health services for the infection. Quantitative, qualitative and mixed method studies reporting on factors related to seeking treatment from modern health services for schistosomiasis were obtained, combining electronic and hand searching. Data extraction and quality assessment of the included articles were performed, with all studies qualitatively analysed using thematic synthesis. A total of 19 studies were included in the review. Six themes were identified from the analysis: biomedical knowledge on schistosomiasis, perceptions of modern treatment and health services, financial considerations of treatment, perceptions on the symptoms, stigma of the infection, and physical location and community. These findings were consistent across studies of different design, setting and quality. Many of the themes identified echo existing literature on health-seeking behaviour. The synthesis also highlighted the role of stigma, and aspects of the physical location and community that may affect treatment-seeking for schistosomiasis. Health education programmes that intend to improve the utilisation of modern health services for the infection need to acknowledge the multiple determinants influencing their use. Future research should move beyond describing health-seeking behaviour to identifying the factors that underlay such behaviour.

Statistical methodological issues in mapping historical schistosomiasis survey data

For schistosomiasis and other neglected tropical diseases for which resources for control are still limited, model-based maps are needed for prioritising spatial targeting of control interventions and surveillance of control programmes. Bayesian geostatistical modelling has been widely and effectively used to generate smooth empirical risk maps. In this paper, we review important issues related to the modelling of schistosomiasis risk, including Bayesian computation of large datasets, heterogeneity of historical survey data, stationary and isotropy assumptions and novel approaches for Bayesian geostatistical variable selection. We provide an example of advanced Bayesian geostatistical variable selection based on historical prevalence data of Schistosoma mansoni in Côte d'Ivoire. We include a "parameter expanded normal mixture of inverse-gamma" prior for the regression coefficients, which in turn allows selection of blocks of covariates, particularly categorical variables. The implemented Bayesian geostatistical variable selection provided a rigorous approach for the selection of predictors within a Bayesian geostatistical framework, identified the most important predictors of S. mansoni infection risk and led to a more parsimonious model compared to traditional selection approaches that ignore the spatial structure in the data. In conclusion, statistical advances in Bayesian geostatistical modelling offer unique opportunities to account for important inherent characteristics of the Schistosoma infection, and hence Bayesian geostatistical models can guide the spatial targeting of control interventions.

Pre- and post-intervention perceptions and water contact behaviour related to schistosomiasis in north-western Tanzania

Schistosomiasis is a widespread disease of public health importance in Tanzania requiring concerted efforts to control it. A study on schistosomiasis-related perceptions and water contact behaviour was undertaken in one community population of Hamuyebe village in Ukerewe district, north-western Tanzania, where intestinal schistosomiasis is endemic before and 2 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention. Data were obtained from baseline and post-intervention knowledge, attitudes and practices (KAP) questionnaire surveys conducted between 2008 and 2010 among 157 individuals aged 15 years and above. The surveys were further complemented by structured observations of human-water contact activities. We found significant increases in respondents' knowledge of the cause, transmission, symptoms and health consequences of schistosomiasis after the intervention. The reported treatment seeking and preventive practices were congruous with the actual (observed) behaviour. Frequency, duration and timing of water contacts also decreased significantly after the intervention and took into consideration the fact that those activities which need larger body surface exposure, for a long period and at an appropriate time when cercarial densities are high (i.e. around noon) are important for the transmission of schistosomiasis. We conclude that PHAST intervention has succeeded in effecting positive changes in peoples' perceptions and attitudes towards water. As a result, knowledge obtained from the said intervention was translated into actions to prevent schistosomiasis. Studies on knowledge, attitudes and practices coupled with structured observations should be part of the integrated approach for the control of schistosomiasis.

Schistosomiasis research in Africa: how the CONTRAST alliance made it happen

In May 2012, the World Health Assembly passed resolution WHA 65.21, calling upon member states to intensify schistosomiasis control and, wherever possible, to attempt transmission interruption and initiate interventions towards local elimination. It is now clear that CONTRAST--a multidisciplinary alliance to optimize schistosomiasis control and transmission surveillance in sub-Saharan Africa--was ahead of the game. Indeed, launched in October 2006, this 4-year project funded by the European Commission made important contributions for sustainable schistosomiasis control in the selected African countries through innovation, validation and application of new tools and locally adapted intervention strategies complementary to preventive chemotherapy. Moreover, CONTRAST articulated a research agenda for schistosomiasis elimination, framed by 10 key questions. Here, we provide a rationale for CONTRAST and discuss its overarching goal, the interrelated objectives, establishment and running of a research node network across Africa, partnership configuration and modus operandi of the project. A collection of 25 articles is presented that are grouped into five main themes: molecular, biological, spatial, social and cross-cutting issues pertaining to the epidemiology and control of schistosomiasis. We summarize key achievements made by CONTRAST, many of which are featured in this special issue of Acta Tropica. Together with an independent view put forth by an eminent schistosomiasis researcher, the current piece provides an umbrella for the 25-article collection, including current gaps and remaining research needs. Finally, post-CONTRAST initiatives are discussed and a speculative viewpoint is given on how schistosomiasis control/elimination will have evolved over the next several years.

Time to set the agenda for schistosomiasis elimination

It is time to raise global awareness to the possibility of schistosomiasis elimination and to support endemic countries in their quest to determine the most appropriate approaches to eliminate this persistent and debilitating disease. The main interventions for schistosomiasis control are reviewed, including preventive chemotherapy using praziquantel, snail control, sanitation, safe water supplies, and behaviour change strategies supported by information, education and communication (IEC) materials. Differences in the biology and transmission of the three main Schistosoma species (i.e. Schistosoma haematobium, S. mansoni and S. japonicum), which impact on control interventions, are considered. Sensitive diagnostic procedures to ensure adequate surveillance in areas attaining low endemicity are required. The importance of capacity building is highlighted. To achieve elimination, an intersectoral approach is necessary, with advocacy and action from local communities and the health community to foster cooperative ventures with engineers, the private sector, governments and non-governmental organizations specialized in water supply and sanitation. Examples of successful schistosomiasis control programmes are reviewed to highlight what has been learnt in terms of strategy for control and elimination. These include St. Lucia and other Caribbean islands, Brazil and Venezuela for S. mansoni; Saudi Arabia and Egypt for both S. mansoni and S. haematobium; Morocco, Tunisia, Algeria, Mauritius and the Islamic Republic of Iran for S. haematobium; Japan and the People's Republic of China for S. japonicum. Additional targets for elimination or even eradication could be the two minor human schistosome species S. guineenisis and S. intercalatum, which have a restricted distribution in West and Central Africa. The examples show that elimination of schistosomiasis is an achievable and desirable goal requiring full integration of preventive chemotherapy with the tools of transmission control. An agenda for the elimination of schistosomiasis would aim to identify the gaps in knowledge, and define the tools, strategies and guidelines that will help national control programmes move towards elimination, including an internationally accepted mechanism that allows verification/confirmation of elimination.

Schistosomiasis in African infants and preschool children: let them now be treated!

The occurrence of schistosomiasis within African infants and preschool children has been much better documented in recent years, revealing an important burden of disease previously overlooked. Despite mounting evidence showing that treatment with praziquantel is safe, beneficial, and could be delivered within ongoing public health interventions, young children still do not have satisfactory access to this drug, and a significant treatment gap exists. Progress towards resolution of this unfortunate health inequity is highlighted, including the development of an appropriate paediatric praziquantel formulation, and present blocks are identified on securing this issue within the international health agenda.

Study and implementation of urogenital schistosomiasis elimination in Zanzibar (Unguja and Pemba islands) using an integrated multidisciplinary approach

Background

Schistosomiasis is a parasitic infection that continues to be a major public health problem in many developing countries being responsible for an estimated burden of at least 1.4 million disability-adjusted life years (DALYs) in Africa alone. Importantly, morbidity due to schistosomiasis has been greatly reduced in some parts of the world, including Zanzibar. The Zanzibar government is now committed to eliminate urogenital schistosomiasis. Over the next 3–5 years, the whole at-risk population will be administered praziquantel (40 mg/kg) biannually. Additionally, snail control and behaviour change interventions will be implemented in selected communities and the outcomes and impact measured in a randomized intervention trial.

Methods/Design

In this 5-year research study, on both Unguja and Pemba islands, urogenital schistosomiasis will be assessed in 45 communities with urine filtration and reagent strips in 4,500 schoolchildren aged 9–12 years annually, and in 4,500 first-year schoolchildren and 2,250 adults in years 1 and 5. Additionally, from first-year schoolchildren, a finger-prick blood sample will be collected and examined for Schistosoma haematobium infection biomarkers. Changes in prevalence and infection intensity will be assessed annually. Among the 45 communities, 15 were randomized for biannual snail control with niclosamide, in concordance with preventive chemotherapy campaigns. The reduction of Bulinus globosus snail populations and S. haematobium-infected snails will be investigated. In 15 other communities, interventions triggering behaviour change have been designed and will be implemented in collaboration with the community. A change in knowledge, attitudes and practices will be assessed annually through focus group discussions and in-depth interviews with schoolchildren, teachers, parents and community leaders. In all 45 communities, changes in the health system, water and sanitation infrastructure will be annually tracked by standardized questionnaire-interviews with community leaders. Additional issues potentially impacting on study outcomes and all incurring costs will be recordedand monitored longitudinally.

Discussion

Elimination of schistosomiasis has become a priority on the agenda of the Zanzibar government and the international community. Our study will contribute to identifying what, in addition to preventive chemotherapy, needs to be done to prevent, control, and ultimately eliminate schistosomiasis, and to draw lessons for current and future schistosomiasis elimination programmes in Africa and elsewhere.

Trial registration

ISRCTN48837681

Intestinal parasitic infections in schoolchildren in different settings of Côte d'Ivoire: effect of diagnostic approach and implications for control

Background

Social-ecological systems govern parasitic infections in humans. Within the frame of assessing the accuracy of a rapid diagnostic test for Schistosoma mansoni in Côte d’Ivoire, three different endemicity settings had to be identified and schoolchildren’s intestinal parasitic infection profiles were characterized.

Methods

In September 2010, a rapid screening was conducted in 11 schools in the Azaguié district, south Côte d’Ivoire. In each school, 25 children were examined for S. mansoni and S. haematobium. Based on predefined schistosome endemicity levels, three settings were selected, where schoolchildren aged 8–12 years were asked to provide three stool and three urine samples for an in-depth appraisal of parasitic infections. Triplicate Kato-Katz thick smears were prepared from each stool sample for S. mansoni and soil-transmitted helminth diagnosis, whereas urine samples were subjected to a filtration method for S. haematobium diagnosis. Additionally, a formol-ether concentration method was used on one stool sample for the diagnosis of helminths and intestinal protozoa. Multivariable logistic regression models were employed to analyse associations between schoolchildren’s parasitic infections, age, sex and study setting.

Results

The prevalences of S. mansoni and S. haematobium infections in the initial screening ranged from nil to 88% and from nil to 56%, respectively. The rapid screening in the three selected areas revealed prevalences of S. mansoni of 16%, 33% and 78%. Based on a more rigorous diagnostic approach, the respective prevalences increased to 33%, 53% and 92% S. haematobium prevalences were 0.8%, 4% and 65% (rapid screening results: 0.0%, 0.0% and 54%). Prevalence and intensity of Schistosoma spp., soil-transmitted helminths and intestinal protozoan infections showed setting-specific patterns. Infections with two or more species concurrently were most common in the rural setting (84%), followed by the peri-urban (28%) and urban setting (18%).

Conclusions

More sensitive diagnostic tools or rigorous sampling approaches are needed to select endemicity settings with high fidelity. The observed small-scale heterogeneity of helminths and intestinal protozoan infections has important implications for control.

Enhancing schistosomiasis control strategy for zimbabwe: building on past experiences

Schistosoma haematobium and Schistosoma mansoni are prevalent in Zimbabwe to levels that make schistosomiasis a public health problem. Following three national surveys to map the disease prevalence, a national policy on control of schistosomiasis and soil transmitted helminths is being developed. This paper reviews the experiences that Zimbabwe has in the area of schistosomiasis control with a view to influence policy. A case study approach to highlight key experiences and outcomes was adopted. The benefits derived from intersectoral collaboration that led to the development of a model irrigation scheme that incorporates schistosomiasis control measures are highlighted. Similarly, the benefits of using plant molluscicides and fish and duck biological agents (Sargochromis codringtonii and Cairina moschata) are highlighted. Emphasis was also placed on the importance of utilizing locally developed water and sanitation technologies and the critical human resource base in the area of schistosomiasis developed over years. After synthesis of the case studies presented, it was concluded that while there is a need to follow the WHO recommended guidelines for schistosomiasis control it is important to develop a control strategy that is informed by work already done in the country. The importance of having a policy and local guidelines for schistosomiasis control is emphasized.

From innovation to application: social-ecological context, diagnostics, drugs and integrated control of schistosomiasis

Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs.

Factors associated with urinary schistosomiasis in two peri-urban communities in south-western Nigeria

In Nigeria, there is only very limited epidemiological information on which the control of human urinary schistosomiasis could be based. In a cross-sectional study, therefore, the prevalences and intensities of, and risk factors for, human infection with Schistosoma haematobium infection were explored in two endemic peri-urban villages in the south-western state of Osun. The villagers' knowledge about the infection and demographic, socio-economic and environmental variables were recorded using a structured questionnaire. Of the 1023 individuals who were investigated, 634 (62.0%) were found infected, with a mean (S.D.) overall intensity of 114.2 (327.7) eggs/10 ml urine. The subjects aged 10-14 years had both the highest prevalence (83.6%) and the highest mean (S.D.) intensity of infection [196.67 (411.7) eggs/10 ml urine]. Most (70.0%) of the subjects appeared to have no knowledge of the transmission of S. haematobium. The results of multivariate regression analysis indicated that infection and moderate-heavy infection (i.e. >50 eggs/10 ml urine) were both associated with: a low family income, of <U.S.$500/month [with adjusted odds ratios (aOR) of 3.72 and 3.35, respectively], the number of children aged 10-15 years living in the household (with aOR of 1.60 and 1.99, respectively), not living with biological parents (with aOR of 1.93 and 5.21, respectively), and living close to (i.e. within a 30-min walk of) the local river (with aOR of 1.38 and 1.61, respectively). Literacy of the family head was, however, a protective factor (with corresponding aOR of 0.28 and 0.30, respectively). Human urinary schistosomiasis appears to be highly endemic in peri-urban/rural Nigeria and closely associated with poverty. To reduce the transmission of S. haematobium in endemic communities, health education that is not only of high quality but also culturally sensitive is needed.

Parasitic worms: knowledge, attitudes, and practices in Western Côte d'Ivoire with implications for integrated control

Background

In the developing world where parasitic worm infections are pervasive, preventive chemotherapy is the key strategy for morbidity control. However, local knowledge, attitudes, and practices (KAP) of parasitic worms are poorly understood, although such information is required for prevention and sustainable control.

Methods

We carried out KAP surveys in two rural communities of Côte d'Ivoire that were subjected to school-based and community-based research and control activities. We used qualitative and quantitative methods. The former included observations, in-depth interviews with key informants, and focus group discussions with school children and adults. Quantitative methods consisted of a structured questionnaire administered to household heads.

Principal Findings

Access to clean water was lacking in both communities and only a quarter of the households had functioning latrines. There was a better understanding of soil-transmitted helminthiasis than intestinal schistosomiasis, but community-based rather than school-based interventions appeared to improve knowledge of schistosomiasis. In the villages with community-based interventions, three-quarters of household interviewees knew about intestinal schistosomiasis compared to 14% in the village where school-based interventions were implemented (P<0.001). Whereas two-thirds of respondents from the community-based intervention village indicated that the research and control project was the main source of information, only a quarter of the respondents cited the project as the main source.

Conclusions/Significance

Preventive chemotherapy targeting school-aged children has limitations, as older population segments are neglected, and hence lack knowledge about how to prevent and control parasitic worm infections. Improved access to clean water and sanitation is necessary, along with health education to make a durable impact against helminth infections.

There is a need to better understand communities' knowledge, attitudes, and practices (KAP) of neglected tropical diseases to improve prevention and control efforts. We studied the socio-cultural aspects of parasitic worm infections in two villages (Mélapleu and Zouatta II) of western Côte d'Ivoire, where research and control activities have been implemented. Zouatta II was exposed to a community-based approach, while school-based interventions were implemented in Mélapleu. KAP surveys were carried out using qualitative and quantitative methods. Although there was some knowledge of parasitic worm infections in both villages, we found important differences between the two villages regarding intestinal schistosomiasis: there was a better understanding of this disease in Zouatta II. However, even the community-based research and control efforts implemented in Zouatta II were ineffective in transforming the information conveyed into preventive behavior related to water contact. Our results suggest that KAP of parasitic worm infections conveyed by research and control activities targeting only school-aged children have shortcomings as older population groups are left out. Hence, for effective control of parasitic worms, children and adults must be educated and interventions should include access to deworming drugs, clean water and sanitation.

Important helminth infections in Southeast Asia diversity, potential for control and prospects for elimination

Besides the 'big three'-HIV/AIDS, malaria and tuberculosis-there are a host of diseases that, by comparison, are truly neglected. These so-called neglected tropical diseases (NTDs), many of which caused by helminths, are intimately linked with poverty and are rampant where housing is poor; access to clean water and adequate sanitation is lacking; hygiene and nutrition is substandard and populations are marginalized and vulnerable. More than a billion people are affected by NTDs, mainly in remote rural and deprived urban settings of the developing world. An overview of papers published in two special thematic volumes of the Advances in Parasitology is provided here under the umbrella of current status of research and control of important helminth infections. A total of 25 comprehensive reviews are presented, which summarise the latest available data pertaining to the diagnosis, epidemiology, pathogenesis, prevention, treatment, control and eventual elimination of NTDs in Southeast Asia and neighbourhood countries. The focus of the first volume provides the current regional status of schistosomiasis, lymphatic filariasis, food-borne trematodiases, echinococcosis and cysticercosis/taeniasis, less common parasitic diseases that can cause epidemic outbreaks and helminth infections affecting the central nervous system. The second volume deals with the tools and strategies for control, including diagnostics, drugs, vaccines and cutting-edge basic research (e.g. the '-omics' sciences). Moreover, cross-cutting themes such as multiparasitism, social sciences, capacity strengthening, geospatial health technologies, health metrics and modelling the potential impact of climate change on helminthic diseases are discussed. Hopefully, these two volumes will become useful for researchers and, most importantly, disease control managers for integrated and sustainable control, rigorous monitoring and eventual elimination of NTDs in Southeast Asia and elsewhere.

Social science implications for control of helminth infections in Southeast Asia

Social science perspectives can inform helminth disease control in Southeast Asia. The social science literature offers theoretical and conceptual models; research methods; recommendations for training and capacity building, health education and health care professional training; and practice guidelines, including implementation of evidence-based interventions. Priority themes include poverty, gender differences, health inequities and access to social resources. Implications for helminth control include broadening disease monitoring and surveillance to include social and economic variables and subjective measures of well-being; training for health professionals and researchers in the social determinants of health; and application of social science models, specifically the expanded 'Chronic Care Model', to the planning and evaluation of interventions. The chapter posits that helminth diseases meet the World Health Organization's expanded definition of chronic conditions, and that integrated delivery of multiple interventions is needed to address the full range of risks and outcomes due to helminth infection.

Control of schistosomiasis in sub-Saharan Africa: progress made, new opportunities and remaining challenges

Several other journal supplements have documented progress made in the control of schistosomiasis in Egypt, China and Brazil, however, with more than 97% of the schistosome infections now estimated to occur in Africa, the relevance of this special issue in Parasitology cannot be overemphasized. In total, 18 articles are presented, inclusive of a lead-editorial from the WHO highlighting a seminal resolution at the 54th World Health Assembly in 2001 that advocated de-worming. Facilitated by a US$ 30 million grant from the Bill and Melinda Gates Foundation in 2002, the Schistosomiasis Control Initiative subsequently fostered implementation of large-scale schistosomiasis (and soil-transmitted helminthiasis) control programmes in six selected African countries. From 2005, CONTRAST, a European union-funded consortium, was formed to conduct multi-disciplinary research pertaining to optimisation of schistosomiasis control. Progress made in schistosomiasis control across sub-Saharan Africa since the turn of the new millennium is reviewed, shedding light on the latest findings stemming from clinical, epidemiological, molecular and social sciences research, inclusive of public health interventions with monitoring and evaluation activities. New opportunities for integrating the control of schistosomiasis and other so-called neglected tropical diseases are highlighted, but more importantly, several opportune questions that arise from it frame the remaining challenges ahead for an enduring solution.