A research agenda for helminth diseases of humans: social ecology, environmental determinants, and health systems

A review of health education activities targeting schoolchildren for the control of soil-transmitted helminthiasis in Southeast Asia, with emphasis upon the Magic Glasses approach

Soil-transmitted helminths continue to be a serious problem causing disease and morbidity globally. Children, mostly school-aged, are more at risk of these infections. The main strategy for control remains to be the mass drug administration (MDA) of antihelminthic drugs. With the limitation of MDA to prevent re-infection, the need for additional approaches such as hygiene education and improvements in water, sanitation and hygiene (WASH) infrastructure are required. Although the importance of health education as a crucial component of an integrated approaches to STH control is highlighted, this component has often been disregarded because the other more complex solutions have been the focus of most studies and programmes. We performed literature searches from four bibliographic databases - Scopus, PubMed, Web of Science and Cochrane Library - to determine availability of studies on the impact of health education interventions targeting STH infections on schoolchildren in Southeast Asia. Our review found only three studies that evaluated health education interventions targeting children. The current lack of evidence in this area suggests the need for more studies assessing the impact of health education intervention for STH control. A successful health education programme for STH called "The Magic Glasses" has been developed targeting schoolchildren in China and the Philippines. This public health intervention displayed significant impact in terms of improving knowledge, attitude and practices, reducing prevalence of STH infections in schoolchildren and encouraging compliance to MDA. This article details the successes and benefits of the Magic Glasses programme as a promising control tool for STH in the Southeast Asian region.

Perceptions and practices of urban slum-dwelling women concerning soil-transmitted helminths infections in Bangladesh: A cross-sectional study

Introduction

Soil-transmitted helminths (STH) infections are still attributed to a significant part of mortality and disabilities in developing nations. This study aimed at exploring the perceptions and practices concerning STH and to assess the associated risk of infections among slum-dwelling women of Dhaka South City Corporations (DSCC), Bangladesh.

Materials and methods

A cross-sectional study was conducted in two selected slums (Malibagh and Lalbagh) of DSCC, Bangladesh, from September 2020 to February 2021. A total of 206 women participants were requested to provide stool samples, followed by a semi-structured questionnaire survey. Parasitological assessment was done by the formol-ether concentration (FEC) technique. Data were analyzed using descriptive statistics, and p-value < 0.05 was considered as statistically significant. An adjusted odds ratio (AOR) with a 95% confidence interval (95% CI) was estimated using logistic regression analysis to examine the association between explanatory and outcome factors.

Results

In total, 36 (17.5%) STH infections were observed out of 206 examined participants. Among the STH, Trichuris trichiura showed the highest prevalence (10.7%), followed by Ascaris lumbricoides (5.3%). Lack of formal education, overcrowded living, large family sizes, and using shared toilets were significantly associated with STH infections. Irregular nail cutting (AOR = 3.12), irregular soap usage after toilet (AOR = 2.98), wearing no shoes (AOR = 4.64), and failing to teach kids to wash their hands (AOR = 3.87) were revealed as practice concerns linked to high STH prevalence. Women, who had never heard about STH (AOR = 2.42) and had no misconceptions regarding STH (AOR = 1.94) were positively related to STH infection in this study.

Conclusion

Slum-dwelling women in Bangladesh still had a substantial infection of STH. Most of the communities under study were unaware of parasite infection and its negative effects on health. Revision of the policy of ongoing anthelmintic distribution programs and widespread health education programs are recommended aimed at controlling STH.

Soil-transmitted helminth infection among school-age children in Ogoja, Nigeria: implication for control

The study aimed at assessing the prevalence and risk factors of soil-transmitted helminthiases among school-aged children in Ogoja Local Government Area, Cross River State. Fecal samples were collected from 504 participants and analyzed using the Kato-Katz technique and modified Baermann technique for identifying larvae of Strongyloides. A total of 232 (46.0%) samples were positive for soil-transmitted helminths. The overall prevalence of Ascaris lumbricoides, hookworm, Trichuris trichiura, and Strongyloides stercoralis were 14.1%, 16.5%, 2.6%, and 12.9% respectively. The prevalence of infections were higher among males (46.6%) than females (45.4%). Overall, parasitic infection was higher in the 5-7-year age group (65.6%) than in the other age groups (p = 0.000). Infection intensities of A. lumbricoides (84.00 EPG) (p = 0.044) and T. trichiura (96.00 EPG) (p = 0.041) were higher in school-age children aged 14-16 years. A. lumbricoides and hookworm co-infection (8.7%) was the most common mixed infection and was significantly higher in males than females. School-aged children who did not have prior knowledge about soil-transmitted helminth infections, the habit of drinking water without boiling, open defecation, use of pit latrine, and children who did not have toilet facilities in school were significantly associated with soil-transmitted helminthiases. There was a significant relationship between washing hands after using the toilet, the habit of putting on footwear outside the house, and soil-transmitted helminth infection. In addition to preventive chemotherapy, control measures should focus on health education, providing clean drinking water, proper disposal of human excreta and sewage, and environmental hygiene.

Participation in health in the Americas: Bibliometric mapping of production, impact, visibility and collaboration

Abstract Participation in health has generated a large number of publications around the world. In order to know the specificities of this production in the Americas, a bibliometric analysis of articles in English, Spanish and Portuguese was carried out. Searches were carried out in the VHL, PubMed, SCOPUS, WOS and SciELO, consolidating a database with 641 references. With the help of the VOSviewer software, we analyzed citation patterns, co-authorship and the chronological distribution by countries and languages. It was possible to verify the growth of production, the quantitative relevance and the impact of the different countries. The analysis indicated that the USA concentrates the largest number of citations and Brazil, despite being the first in number of publications, is the third in number of citations. The same occurs with Brazilian journals that, with the largest number of articles, fall in the ranking of the most cited. The co-authorship analysis indicated that the University of Toronto, Fiocruz and Harvard University have the most formal collaborations with other organizations. We conclude that there are inequalities of impact, visibility and internationalization in this field, indicating obstacles to scientific development and health policies.

Participation in health in the Americas: Bibliometric mapping of production, impact, visibility and collaboration

Participation in health has generated a large number of publications around the world. In order to know the specificities of this production in the Americas, a bibliometric analysis of articles in English, Spanish and Portuguese was carried out. Searches were carried out in the VHL, PubMed, SCOPUS, WOS and SciELO, consolidating a database with 641 references. With the help of the VOSviewer software, we analyzed citation patterns, co-authorship and the chronological distribution by countries and languages. It was possible to verify the growth of production, the quantitative relevance and the impact of the different countries. The analysis indicated that the USA concentrates the largest number of citations and Brazil, despite being the first in number of publications, is the third in number of citations. The same occurs with Brazilian journals that, with the largest number of articles, fall in the ranking of the most cited. The co-authorship analysis indicated that the University of Toronto, Fiocruz and Harvard University have the most formal collaborations with other organizations. We conclude that there are inequalities of impact, visibility and internationalization in this field, indicating obstacles to scientific development and health policies.

Participación en salud em las Américas: mapeo bibliométrico de producción, impacto, isibilidade y colaboración

Resumen La participación en salud ha generado una gran cantidad de publicaciones alrededor del mundo. Para conocer las especificidades de esta producción en las Américas, se realizó un análisis bibliométrico de artículos en inglés, español y portugués. Se realizaron búsquedas en la BVS, Pubmed, SCOPUS, WOS y SciELO, consolidando una base de datos con 641 referencias. Con la ayuda del software VOSviewer, analizamos los patrones de citación, la coautoría y la distribución cronológica por países e idiomas. Se pudo verificar el crecimiento de la producción, la relevancia cuantitativa y el impacto de los diferentes países. El análisis indicó que EE.UU. concentra el mayor número de citas y Brasil, a pesar de ser el primero en número de publicaciones, es el tercero en número de citas. En los diez artículos más citados se descartan trabajos desarrollados en EE.UU. y Canadá. El análisis de coautoría indicó que la Universidad de Toronto, Fiocruz y la Universidad de Harvard tienen las colaboraciones más formales con otras organizaciones. Concluimos que existen desigualdades de impacto, visibilidad e internacionalización en este campo, indicando obstáculos para el desarrollo científico y las políticas de salud.

Current Research of Phytochemical, Medicinal and Non-Medicinal Uses of Uncaria gambir Roxb.: A Review

Uncaria gambir Roxb. is a plant from Southeast Asia and is widely used as an alternative medicine with various applications. This plant has been widely used in traditional medicine. This paper aims to provide information on U. gambir, a summary of data on phytochemicals and on medical and nonmedical activities. Phytochemical studies reveal biologically active constituents such as flavonoids, phenolics, and alkaloids. Various studies have shown that extracts and compounds obtained from U. gambir have medical uses for their antioxidant, antibacterial, anti-helminthic, anticancer, antifungal, anti-inflammatory, anti-hyperglycemic, anti-hyperuricemic, anti-lipid peroxidation, antihyperlipidemic and other properties. In addition, this extract has other uses, such as adsorbent for dyes and metal ions, as well as corrosion inhibition. Thus, U. gambir, which is commonly used in traditional medicine, is a potential plant for many therapeutic applications and prospects for drug development as well as other applications such as adsorbent and corrosion inhibition.

Exposure, hazard, and vulnerability all contribute to Schistosoma haematobium re-infection in northern Senegal

Background

Infectious disease risk is driven by three interrelated components: exposure, hazard, and vulnerability. For schistosomiasis, exposure occurs through contact with water, which is often tied to daily activities. Water contact, however, does not imply risk unless the environmental hazard of snails and parasites is also present in the water. By increasing reliance on hazardous activities and environments, socio-economic vulnerability can hinder reductions in exposure to a hazard. We aimed to quantify the contributions of exposure, hazard, and vulnerability to the presence and intensity of Schistosoma haematobium re-infection.

Methodology/Principal findings

In 13 villages along the Senegal River, we collected parasitological data from 821 school-aged children, survey data from 411 households where those children resided, and ecological data from all 24 village water access sites. We fit mixed-effects logistic and negative binomial regressions with indices of exposure, hazard, and vulnerability as explanatory variables of Schistosoma haematobium presence and intensity, respectively, controlling for demographic variables. Using multi-model inference to calculate the relative importance of each component of risk, we found that hazard (Ʃw_{i =} 0.95) was the most important component of S. haematobium presence, followed by vulnerability (Ʃw_i = 0.91). Exposure (Ʃw_i = 1.00) was the most important component of S. haematobium intensity, followed by hazard (Ʃw_i = 0.77). Model averaging quantified associations between each infection outcome and indices of exposure, hazard, and vulnerability, revealing a positive association between hazard and infection presence (OR = 1.49, 95% CI 1.12, 1.97), and a positive association between exposure and infection intensity (RR 2.59–3.86, depending on the category; all 95% CIs above 1)

Conclusions/Significance

Our findings underscore the linkages between social (exposure and vulnerability) and environmental (hazard) processes in the acquisition and accumulation of S. haematobium infection. This approach highlights the importance of implementing both social and environmental interventions to complement mass drug administration.

While the impacts of natural hazards tend to be described in terms of social determinants such as exposure and vulnerability, the risk for infectious disease is often expressed in terms of environmental determinants without fully considering the socio-ecological processes that put people in contact with infective agents of disease. In the case of schistosomiasis, risk is determined by human interactions with freshwater environments where schistosome parasites circulate between people and aquatic snails. In this study, we quantified the relative contributions of exposure, hazard, and vulnerability to schistosome re-infection among schoolchildren in an endemic region of northern Senegal. We find that hazard and vulnerability influence whether a child becomes infected, while exposure and hazard influence the burden of worms once infection is acquired. Increasing numbers of worms is known to be positively associated with increasing severity of disease. Our findings underscore the importance of evaluating social and environmental determinants of disease simultaneously; omitting measures of exposure, hazard or vulnerability may limit our understanding of risk.

Eliminating onchocerciasis within the Meme River Basin of Cameroon: A social-ecological approach to understanding everyday realities and health systems

BACKGROUND

Onchocerciasis affects some of the world's most marginalized people, perpetuating poverty and inequalities. Mass Drug Administration (MDA) with Ivermectin has taken place within the Meme River basin region in Cameroon for over 15 years. Despite this, onchocerciasis is still prevalent in the region due to existing and emerging contextual challenges. Using a social-ecological approach we explore the everyday realities of communities, highlighting the challenges and potential solutions that could support Neglected Tropical Disease (NTD) programmes when transitioning from control to elimination of onchocerciasis in this highly endemic area and other similar communities.

METHODOLOGY/PRINCIPAL FINDING

In-depth interviews (71) with community members and Community Drug Distributors (CDDs) were conducted to understand current knowledge, attitudes, and behaviours in relation to transmission, prevention and treatment of onchocerciasis. Through application of the social-ecological model, four key themes were identified: 1. Contextual factors on health promotion interventions (Onchocerciasis history and understanding of the disease, prevention and mitigation strategies and MDA experience); 2. Social determinants (poverty and livelihoods, economic and social impacts on CDD volunteers and stigma); 3. Environmental determinants (exposure, housing, occupation and poverty); and 4. health seeking pathways and decision making for treatment (access, cost and preferable treatment routes). We discuss these core and cross cutting themes (gender differences and community participation/ownership) in relation to intersectoral collaboration, gender equity and health systems support, making recommendations for NTD programmes within the context of integrated and interdisciplinary approaches. These include the need for; intersectional and gender analysis at the local level, addressing environmental dimensions of onchocerciasis through integrated and regular health promotion, vector control strategies and access to safe water sources; reflection and action that embeds responses to social and economic barriers to MDA; integrated case detection and management that is responsive to onchocerciasis symptoms and related stigma and a fair and just support network for CDDs.

CONCLUSION/SIGNIFICANCE

NTD programmes need to respond to diverse community circumstances and behaviours. Communities are not a homogeneous risk group and treating them in this way will delay elimination. A deeper understanding of individual needs and their capacity to seek prevention and treatment must be considered if onchocerciasis is to be eliminated and the remaining impacts managed.

Lymphatic filariasis elimination endgame in an urban Indian setting: the roles of surveillance and residual microfilaremia after mass drug administration

BACKGROUND

To secure the gains of lymphatic filariasis (LF) elimination programs, attention is needed to the 'residual microfilaremia phase', in which high-risk populations may be crucial. The present study documents the impact of mass drug administration (MDA) in the urban Indian setting of Surat City, with high rates of in-migration.

METHODS

Epidemiological assessment included National Filaria Control Program (NFCP) and World Health Organization recommended routine and pre-MDA microfilaremia surveys respectively. Routine filaria surveys were conducted around the year in approximately 2000-4000 people per month, while pre-MDA surveys were carried out annually among approximately 4000 people from four fixed and four random sites. In 2016, Transmission Assessment Survey (TAS) was done in primary school children. The outcomes were microfilaremia (Mf) and antigen prevalence; more specifically, microfilaremia according to place of birth, in pre-MDA and routine night blood smears (NBS) collected from 2008 to 2015. Prevalence ratios and confidence intervals were calculated.

RESULTS

A total of 25 480 pre-MDA and 306 198 routine NBS were examined during the study. In 2008, the Mf prevalence in the routine survey was 63/18 814 (0.33%), declining to 23/39 717 (0.06%) in 2016. Pre-MDA surveys showed a similar decrease from 47/4184 (1.1%) in 2008 to 12/4042 (0.3%) in 2015. In those born outside Surat, microfilaremia decreased below transmission thresholds, but remained more than treble that of the remainder of the population, in both the pre-MDA surveys [prevalence ratio: 3.17, 95% confidence interval (CI): 1.15-8.72], and the routine surveys (3.31, 95% CI: 1.47-7.48). Though the TAS results indicated that MDA endpoints had been reached, sub-group analysis identified that 90% of antigenemic children were from families of high-risk groups.

CONCLUSIONS

Extensive long-term epidemiological monitoring suggests that all the urban population, including high-risk groups, have benefitted from the ELF program. To prevent re-establishment of infection in large urban areas with unsanitary conditions conducive to filarial vector breeding, there is need to identify residual microfilaremia by customized surveys in addition to pre-MDA monitoring and TAS. The present findings can be used to develop strategies to prioritize screening, surveillance and plan treatment of high-risk groups after achieving MDA endpoints.

Characterization of Moxidectin against Strongyloides ratti: In Vitro and In Vivo Activity and Pharmacokinetics in the Rat Model

Strongyloides stercoralis is a soil-transmitted helminth affecting an estimated 30-100 million people. Since the infection may be severe and life-threatening, accessible and effective treatment is pivotal. Currently, ivermectin is the drug of choice but has limitations. Moxidectin, a veterinary anthelminthic approved for use in human onchocerciasis, is a promising drug alternative against strongyloidiasis. In this study, we evaluated the in vitro activity of moxidectin on Strongyloides ratti larvae (L₃) and adult females and the activity as well as the pharmacokinetics of moxidectin in S. ratti infected rats. In vitro, moxidectin had an activity that was similar to that of ivermectin, with median lethal concentration values for L₃ and adults in the range of 0.08-1.44 μM, after 72 h of exposure. In vivo, doses of 250, 500, and 750 μg/kg of moxidectin resulted in a reduction of the worm burden ranging from 48.5 to 75%. At the highest dose (750 μg/kg) we observed a maximal blood concentration of 50.3 ng/mL and an area under the curve of 895.2 ng × h/mL. The half-life in rats was 9 h, and moxidectin was cleared to undetectable blood levels within 7 d (<10 ng/mL). No exposure-response relationship was observed. This work contributes to the characterization of moxidectin in the treatment of S. ratti as a model of Strongyloides spp. and, as such, supports moving moxidectin further along the drug development pipeline in the treatment of human strongyloidiasis.

Masculinity and misinformation: Social dynamics of liver fluke infection risk in Thailand

Liver fluke infection through the consumption of raw or undercooked freshwater fish is a major public health problem in the Mekong Region. Despite the extensive efforts of liver fluke health campaigns, Northeast Thailand still reports high human infection prevalence as consumption of raw fish dishes has diminished but not ceased. This study examines the roles of social-cultural factors, particularly the influences of masculinity and misinformation, on liver fluke infection risk. Participant observation, questionnaire surveys and semi-structured interviews were conducted in four villages in Kalasin Province, Thailand, to scrutinize reasons for raw fish consumption, gender differences in raw fish culture, processes of liver fluke information dissemination, and the extent of information mismatch. Our results show that one of the key reasons (76.9%) underlying continued raw fish consumption are deeply embedded cultural practices associated with ways of rural life. About 30% of the participants indicated that they would not avoid eating raw fish, regardless of knowing the health consequences. Gender difference is evident, with 75.6% of males consuming raw fish salad (koi pla), compared to 42.7% of females. Some male participants associate raw meat consumption with virility and strength. Such beliefs underscore the cultural linkage of koi pla consumption with masculinity. Misconceptions of liver fluke life cycle and risk of infection remain, as only 15.3% of the participants correctly selected raw fish as the food source for liver fluke infection while 84.2% misunderstood that other raw foods could lead to infection. The multi-layered and hierarchical structure of public health information dissemination from medical professionals to health officers and village health volunteers to villagers has contributed to information mismatch between different layers. Our study builds on others which call for multi-pronged scientific and social strategies, as well as culturally attuned approaches to public health messaging. The study raises masculinity and misinformation as relevant considerations in disease prevention. Incorporating grounded research and gendered perspectives are part of appreciating the cultural roots of raw fish consumption. Realizing the significant role of village health volunteers in information dissemination and in supplying coherent public health messages is vital for effective health campaigns.

The Impact of Neglected Tropical Diseases (NTDs) on Women's Health and Wellbeing in Sub-Saharan Africa (SSA): A Case Study of Kenya

Neglected Tropical Diseases (NTDs) trap individuals in a cycle of poverty through their devastating effects on health, wellbeing and social–economic capabilities that extend to other axes of inequity such as gender and/or ethnicity. Despite NTDs being regarded as equity tracers, little attention has been paid toward gender dynamics and relationships for gender-equitable access to NTD programs in sub-Saharan Africa (SSA). This paper examines the impact of NTDs on women’s health and wellbeing in SSA using Kenya as a case study. This research is part of a larger research program designed to examine the impact of NTDs on the health and wellbeing of populations in Kenya. Thematic analysis of key informants’ interviews (n = 21) and focus groups (n = 5) reveals first that NTDs disproportionately affect women and girls due to their assigned gender roles and responsibilities. Second, women face financial and time constraints when accessing health care due to diminished economic power and autonomy. Third, women suffer more from the related social consequences of NTDs (that is, stigma, discrimination and/or abandonment), which affects their health-seeking behavior. As such, we strongly suggest a gender lens when addressing NTD specific exposure, socio-economic inequities, and other gender dynamics that may hinder the successful delivery of NTD programs at the local and national levels.

Assessment of the prevalence of intestinal parasitic infections and associated habit and culture-related risk factors among primary schoolchildren in Debre Berhan town, Northeast Ethiopia

Background

Intestinal parasitic infections (IPIs) are still among the major public health issues in developing countries. Assessing the prevalence of IPIs and potential risk factors in different localities is essential to enhance control strategies. To date, no prevalence assessment study was conducted in Debre Berhan town. Therefore, the aim of this study was to assess the prevalence of IPIs and associated habit and culture-related risk factors among primary schoolchildren in Debre Berhan town, Northeast Ethiopia.

Method

School based cross-sectional study was conducted from April to June 2017. A total of 645 children aged 6–15 years were selected from six primary schools in Debre Berhan town via a multistage random sampling technique. A structured questionnaire was used to collect data about sociodemographic and potential risk factor variables. Fresh stool samples were collected from each child and examined using direct smear and formal-ether concentration technique.

Result

Among the 645 children participated in the study, 341 (52.9%) were infected by one or more intestinal parasites. Helminths (33.8%) were more prevalent than protozoa (20%). Double parasitic infection rate was 0.9%. The predominant parasites were Ascaris lumbricoides (22.6%), Entamoeba histolytica/dispar/moshkovskii (18.1%) and Hymenolepis nana (5.7%). Multivariable logistic regression analysis showed that age of child (6–9 years), family size (above 5), mother’s illiteracy and primary education, father’s illiteracy, urban-farmer father, manual-worker father, not washing hands before eating, unclean fingers, open defecation site (ODS) near residence, latrine type, cultural response to dropped food (cleaning and eating; ‘kiss and replace’), habit of playing with waste water, habit of playing with soil, habit of sucking fingers and habit of eating when playing were significantly associated with IPIs (p< 0.05). Likewise, age (6–9 years), mother’s illiteracy, urban-farmer father, not washing hands before eating, ODS near residence, tradition of cleaning and eating dropped food, habit of playing with soil, sucking fingers and eating when playing were identified as significant risk factors of A. lumbricoides infection.

Conclusion

High prevalence of IPIs among the study participants demands improvement of environmental sanitation, personal hygiene, and health education regarding the potential habit and culture-related risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-10148-y.

Spatiotemporal clusters of schistosomiasis mortality and association with social determinants of health in the Northeast region of Brazil (1980-2017)

The Northeast region of Brazil includes the states with the highest prevalence for schistosomiasis mansoni (SM). This study aimed to evaluate the spatiotemporal patterns of SM mortality and to analyze this association with social determinants in health. We conducted an ecological time series study (1980-2017), using spatial analysis tools. Time trend analysis was performed by joinpoint regression. Maps representing mortality rates for SM were constructed and Moran Index was calculated to analyze spatial autocorrelation. A total of 13,720 deaths from SM were reported in this period. The states of Pernambuco (PE) (50.62%) and Alagoas (AL) (22.09%) had the highest mortality percentages. The mortality rate decreased from 1.28 to 0.63 along the time. Although most states showed a stable trend, Sergipe (SE) and Bahia (BA) showed increasing trends in the latest years. Additionally, the spatial analysis showed the concentration of municipalities that presented high risk in the coastal region of the states of PE, AL, SE, and BA. Lastly, mortality rates were correlated with social and educational indicators and hospitalizations for diarrhea. Altogether, these results demonstrate that some states showed stable or increasing trends of SM mortality in the last period of the studied time interval.

A first nation-wide assessment of soil-transmitted helminthiasis in Fijian primary schools, and factors associated with the infection, using a lymphatic filariasis transmission assessment survey as surveillance platform

BACKGROUND

Soil-transmitted helminthiasis (STH) is endemic in Fiji but its prevalence is not known and likely to have changed after a decade of mass drug administration (MDA) for lymphatic filariasis (LF). By linking with LF transmission assessment surveys (LF-TAS), we undertook the first nation-wide assessment of STH in Fijian primary schools, as well as an analysis of factors associated with STH infections.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional assessment for STH was conducted in all four Divisions of Fiji from 2014 to 2015. In the Western, Central, and Northern Divisions, schools were sub-sampled after LF-TAS, while, in the Eastern Division, schools were selected via simple random sampling. For the diagnosis of STH, stool samples were examined by coproscopy with a single Kato-Katz thick smear (KK) and the formol-ether-acetate concentration technique, except for the samples from the Eastern Division where only KK was used. Mean prevalence of any STH among class 1-2 students at the national level was 10.5% (95% CI: 6.9-15.5). Across the three Divisions via LF-TAS, the prevalence levels for ascariasis were 8.7% (95% CI: 4.3-16.6), hookworm 3.9% (95% CI: 2.3-6.6) and trichuriasis 0%. In the Eastern Division, ascariasis prevalence was 13.3% (95% CI: 6.4-25.6), and hookworm 0.7% (95% CI: 0.2-2.5), with one case of trichuriasis. Among class 3-8 students, ascariasis prevalence was lower. Lower risk of any STH was associated with wearing shoes (adjusted OR 0.54, 95% CI: 0.32-0.90) and having piped water from the Fiji Water Authority at home (adjusted OR 0.48, 95% CI: 0.25-0.92).

CONCLUSIONS

After a decade of community-based LF-MDA, STH in school-age children in Fiji is now close to 10%, but localities of endemicity remain. Preventive chemotherapy should be maintained in areas with elevated STH prevalence alongside targeted delivery of integrated WASH interventions. LF-TAS has provided an opportunity to develop future public health surveillance platforms.

The Ecological Importance of Amphipod–Parasite Associations for Aquatic Ecosystems

Amphipods are a key component of aquatic ecosystems due to their distribution, abundance and ecological role. They also serve as hosts for many micro- and macro-parasites. The importance of parasites and the necessity to include them in ecological studies has been increasingly recognized in the last two decades by ecologists and conservation biologists. Parasites are able to alter survival, growth, feeding, mobility, mating, fecundity and stressors’ response of their amphipod hosts. In addition to their modulating effects on host population size and dynamics, parasites affect community structure and food webs in different ways: by increasing the susceptibility of amphipods to predation, by quantitatively and qualitatively changing the host diet, and by modifying competitive interactions. Human-induced stressors such as climate change, pollution and species introduction that affect host–parasite equilibrium, may enhance or reduce the infection effects on hosts and ecosystems. The present review illustrates the importance of parasites for ecosystem processes using examples from aquatic environments and amphipods as a host group. As seen from the literature, amphipod–parasite systems are likely a key component of ecological processes, but more quantitative data from natural populations and field evidence are necessary to support the results obtained by experimental research.

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.

Genetic diversity of Echinococcus vogeli in the western Brazilian Amazon

Human polycystic echinococcosis is a parasitic infection caused by the larval stage of Echinococcus vogeli, which occurs in rural areas of Central and South America. Until now, little information on the genetic variability of E. vogeli is available. Here, 32 samples from human-excised E. vogeli cysts had a 396-bp sequence of the mitochondrial cytochrome oxidase I (COI) gene sequenced and compared to another 17 COI sequences representing nine Echinococcus species. A Bayesian COI tree revealed that all E. vogeli sequences formed a monophyletic and well-supported clade with an E. vogeli reference sequence. The occurrence of geographically restricted E. vogeli COI haplotypes suggests retention of ancestral polymorphisms with little migration in Acre, Brazil.

Risk of Soil-Transmitted Helminthiasis among Agrarian Communities of Kogi State, Nigeria

Background:

Soil-transmitted helminths (STH) have remained a major threat to humans, especially children in developing countries, including Nigeria. Interventions have always been geared towards school-aged children, neglecting preschool-aged children and occupational risk adults. The Soil-Transmitted Helminthiasis Advisory Committee (STHAC) recently suggested incorporating other at-risk groups.

Objective:

This study assessed the associated risk of STH infection among agrarian communities of Kogi State, Nigeria.

Methods:

A total of 310 individuals of all ages participated in the cross-sectional survey. Stool samples were analyzed using standard Kato-Katz method.

Results:

A total of 106 (34.2%) individuals were infected with at least one STH. Hookworm was the most prevalent (18.1%); followed by Ascaris lumbricoides (16.8%). Worm intensity was generally light. Prevalence of infection was similar between four age groups considered (preschool, school, ‘women of reproductive age’ and older at-risk group). Poor socio-economic status (SES) was a major risk for STH infection. Using a 20-asset based criteria, 68 (23.1%) and 73 (24.7%) of 295 questionnaire respondents were classified into first (poorest) and fifth (richest) wealth quintiles respectively. Risk of infection with STH was 60% significantly lower in the richest wealth quintile compared to the poorest (Prevalence Ratio [PR] = 0.4843, 95% CI = 0.2704–0.8678, p = 0.015). Open defecators were more likely to harbour STH than those who did not (PR = 1.7878, 95% CI = 1.236–2.5846, p = 0.00201). Pit latrine and water closet toilets each approximately reduced STH infection by 50% (p < 0.05).

Conclusion:

Preventive chemotherapy for all age groups, health education and provision of basic amenities especially toilets are needed in order to achieve the goal toward the 2020 target of STH control.

Using physical contact heterogeneity and frequency to characterize dynamics of human exposure to nonhuman primate bodily fluids in central Africa

Emerging infectious diseases of zoonotic origin constitute a recurrent threat to global health. Nonhuman primates (NHPs) occupy an important place in zoonotic spillovers (pathogenic transmissions from animals to humans), serving as reservoirs or amplifiers of multiple neglected tropical diseases, including viral hemorrhagic fevers and arboviruses, parasites and bacteria, as well as retroviruses (simian foamy virus, PTLV) that are pathogenic in human beings. Hunting and butchering studies in Africa characterize at-risk human social groups, but overlook critical factors of contact heterogeneity and frequency, NHP species differences, and meat processing practices. In southeastern Cameroon, a region with a history of zoonotic emergence and high risk of future spillovers, we conducted a novel mixed-method field study of human physical exposure to multiple NHP species, incorporating participant-based and ecological methodologies, and qualitative interviews (n = 25). We find frequent physical contact across adult human populations, greater physical contact with monkeys than apes, especially for meat handling practices, and positive correlation of human exposure with NHP species abundance and proximity to human settlement. These fine-grained results encourage reconsideration of the likely dynamics of human-NHP contact in past and future NTD emergence events. Multidisciplinary social science and ecological approaches should be mobilized to generate more effective human and animal surveillance and risk communications around neglected tropical diseases. At a moment when the WHO has included "Disease X", a presumably zoonotic pathogen with pandemic potential, on its list of blueprint priority diseases as, new field-based tools for investigating zoonotic disease emergence, both known and unknown, are of critical importance.

General contextual effects on neglected tropical disease risk in rural Kenya

The neglected tropical diseases (NTDs) are characterized by their tendency to cluster within groups of people, typically the poorest and most marginalized. Despite this, measures of clustering, such as within-group correlation or between-group heterogeneity, are rarely reported from community-based studies of NTD risk. We describe a general contextual analysis that uses multi-level models to partition and quantify variation in individual NTD risk at multiple grouping levels in rural Kenya. The importance of general contextual effects (GCE) in structuring variation in individual infection with Schistosoma mansoni, the soil-transmitted helminths, Taenia species, and Entamoeba histolytica/dispar was examined at the household-, sublocation- and constituency-levels using variance partition/intra-class correlation co-efficients and median odds ratios. These were compared with GCE for HIV, Plasmodium falciparum and Mycobacterium tuberculosis. The role of place of residence in shaping infection risk was further assessed using the spatial scan statistic. Individuals from the same household showed correlation in infection for all pathogens, and this was consistently highest for the gastrointestinal helminths. The lowest levels of household clustering were observed for E. histolytica/dispar, P. falciparum and M. tuberculosis. Substantial heterogeneity in individual infection risk was observed between sublocations for S. mansoni and Taenia solium cysticercosis and between constituencies for infection with S. mansoni, Trichuris trichiura and Ascaris lumbricoides. Large overlapping spatial clusters were detected for S. mansoni, T. trichiura, A. lumbricoides, and Taenia spp., which overlapped a large cluster of elevated HIV risk. Important place-based heterogeneities in infection risk exist in this community, and these GCEs are greater for the NTDs and HIV than for TB and malaria. Our findings suggest that broad-scale contextual drivers shape infectious disease risk in this population, but these effects operate at different grouping-levels for different pathogens. A general contextual analysis can provide a foundation for understanding the complex ecology of NTDs and contribute to the targeting of interventions.

Are schoolchildren less infected if they have good knowledge about parasitic worms? A case study from rural Côte d'Ivoire

BACKGROUND

Parasitic worms (helminths) are common infections in low- and middle-income countries. For most helminth species, school-aged children are at highest risk of infection and morbidity, such as impaired cognitive and physical development. Preventive chemotherapy is the current mainstay for helminthiases control. Sanitation improvement and hygiene-related education are important complementary strategies, which act by altering children's behaviour. However, little is known about the effect of improved knowledge on the risk of helminth infection. The aim of this study was to assess the potential influence of knowledge that children acquired at home or in school, without any specific health education intervention, on helminth infections.

METHODS

In May 2014, we conducted a cross-sectional survey in western Côte d'Ivoire. A total of 2498 children, aged 9-12 years, were subjected to three consecutive stool examinations using duplicate Kato-Katz thick smears to determine infections with soil-transmitted helminths and Schistosoma mansoni. Additionally, children were interviewed to assess their knowledge about helminth infections. Four knowledge scores were constructed by factor analysis; one, reflecting general knowledge about helminths and three manifesting helminth species-specific knowledge. The effect of general and specific knowledge on children's helminth infection status was determined using meta-analysis.

RESULTS

Children who scored high in the hookworm-specific knowledge were less likely to be infected with hookworm but no association was found for the other helminth species. Moreover, greater general knowledge was not associated with lower odds of being infected with any helminth species. Most of the children interviewed believed that the effect of preventive chemotherapy is permanent, and hence, re-treatment is not necessary.

CONCLUSIONS

Specific knowledge about different types of helminths might not suffice to induce behavioural change which in turn reduces infection and reinfection with helminths. Health education interventions should strive to strengthen the perception of risk and to clarify the true benefit of preventive chemotherapy.

Nanomedicine Approaches Against Parasitic Worm Infections

Nanomedicine approaches have the potential to transform the battle against parasitic worm (helminth) infections, a major global health scourge from which billions are currently suffering. It is anticipated that the intersection of two currently disparate fields, nanomedicine and helminth biology, will constitute a new frontier in science and technology. This progress report surveys current innovations in these research fields and discusses research opportunities. In particular, the focus is on: (1) major challenges that helminth infections impose on mankind; (2) key aspects of helminth biology that inform future research directions; (3) efforts to construct nanodelivery platforms to target drugs and genes to helminths hidden in their hosts; (4) attempts in applying nanotechnology to enable vaccination against helminth infections; (5) outlooks in utilizing nanoparticles to enhance immunomodulatory activities of worm-derived factors to cure allergy and autoimmune diseases. In each section, achievements are summarized, limitations are explored, and future directions are assessed.

Socioenvironmental factors associated with Schistosoma mansoni infection and intermediate hosts in an urban area of northeastern Brazil

Schistosomiasis, which is caused by trematodes of the genus Schistosoma and by the species Schistosoma mansoni in Brazil, is transmitted primarily by Biomphalaria glabrata mollusks. Infections occur in humans and mollusks in freshwater environments contaminated with feces from infected humans. This study aimed to evaluate potential foci of schistosomiasis based on the identification of infection sites for the snails, factors that increased the human infection probability of S. mansoni infection, and the relationship of the disease with abiotic, biotic, and sociocultural factors. The study was conducted in an urban area on the northeast coast of Brazil; this location was chosen based on the following factors: the presence of B. glabrata, nearby freshwater, and the absence of sewer treatment. A parasitological analysis was performed to evaluate infections of the mollusks and residents inside the perimeter defined by the collection points. Questionnaires were applied to obtain demographic data and to identify behaviors that led to human infection. To verify the contamination of freshwater by human feces, a microbiological analysis of the water was performed at the mollusk collection points to determine the rate of contamination with fecal coliforms. A total of 10,270 B. glabrata mollusks were collected between August 2013 and August 2014, of which 8.8% were positive for S. mansoni; the prevalence ranged from 0 to 34.5% over the study period. A total of 232 coprological samples from the residents were analyzed. The S. mansoni infection prevalence rate was 16.4%, and the S. mansoni parasitic load in the infected residents was 54.9 eggs per gram of feces on average. Males were more affected by the parasite, especially in the 8-17-year-old age range. Thermotolerant coliforms were observed at the mollusk collection sites, which indicated that freshwater and sewage were in continuous contact. This contamination indicated poor sanitary conditions, as was previously observed, which could be combined with detrimental behavior due to the residents' habits. These conditions cause a predisposition for both intermediate and definitive infections of the hosts by creating a socioenvironmental scenario that is conducive to the formation and maintenance of potential schistosomiasis foci. This and similar areas deserve special attention from the government with an aim of improving sanitation services and local resident knowledge to prevent future contamination.

Anthelmintic effects of indigenous multipurpose fodder tree extracts against Haemonchus contortus

Condensed tannins (CT) extracted from Balanites aegyptiaca, Tamarindus indica, and Celtis toka browses were used to evaluate their anthelmintic effect on different developmental stages of Haemonchus contortus. To achieve this objective, various serial concentrations of each CT extract of the foliages were used to test adult motility, inhibition of egg hatchability, and larval development. The fodders were selected based on their multipurpose advantage and accessibility to use as fodder for livestock in the low lands of the Gambella region. The fastest and slowest adult motility rate was observed in 2-ml (4 min) and 0.125-ml dose of C. toka, respectively, which is better than that in ivermectin. Egg hatchability inhibition was observed with dose difference within species, but there is no difference between B. aegyptiaca and T. indica. The foliage extracts of the studied browses were observed to inhibit the larvae by 100% at 2 ml, which is similar to ivermectin. There is no significant difference observed in larvae development inhibition between the species and ivermectin (p > 0.05). CT extracts of studied plants have found to own significant anthelmintic activity in a dose-dependent manner. They could serve as anthelmintic economically and eco-friendly after further and series of in vivo experiments.

Schistosoma mansoni reinfection: Analysis of risk factors by classification and regression tree (CART) modeling

Praziquantel (PZQ) is an effective chemotherapy for schistosomiasis mansoni and a mainstay for its control and potential elimination. However, it does not prevent against reinfection, which can occur rapidly in areas with active transmission. A guide to ranking the risk factors for Schistosoma mansoni reinfection would greatly contribute to prioritizing resources and focusing prevention and control measures to prevent rapid reinfection. The objective of the current study was to explore the relationship among the socioeconomic, demographic, and epidemiological factors that can influence reinfection by S. mansoni one year after successful treatment with PZQ in school-aged children in Northeastern Minas Gerais state Brazil. Parasitological, socioeconomic, demographic, and water contact information were surveyed in 506 S. mansoni-infected individuals, aged 6 to 15 years, resident in these endemic areas. Eligible individuals were treated with PZQ until they were determined to be negative by the absence of S. mansoni eggs in the feces on two consecutive days of Kato-Katz fecal thick smear. These individuals were surveyed again 12 months from the date of successful treatment with PZQ. A classification and regression tree modeling (CART) was then used to explore the relationship between socioeconomic, demographic, and epidemiological variables and their reinfection status. The most important risk factor identified for S. mansoni reinfection was their “heavy” infection at baseline. Additional analyses, excluding heavy infection status, showed that lower socioeconomic status and a lower level of education of the household head were also most important risk factors for S. mansoni reinfection. Our results provide an important contribution toward the control and possible elimination of schistosomiasis by identifying three major risk factors that can be used for targeted treatment and monitoring of reinfection. We suggest that control measures that target heavily infected children in the most economically disadvantaged households would be most beneficial to maintain the success of mass chemotherapy campaigns.

Fish sharing as a risk factor for Opisthorchis viverrini infection: evidence from two villages in north-eastern Thailand

BACKGROUND

Foodborne trematodiasis (FBT) is a significant global health problem, with the liver flukes Opisthorchis viverrini, O. felineus, and Clonorchis sinensis contributing to half of the global burden of FBT. North-eastern Thailand where O. viverrini is endemic and un-cooked fish dishes remain an integral part of the food culture has the highest reported incidence of opisthorchiasis, including associated cholangiocarcinoma. Both food sharing and eating practices are potentially important factors in FTB, suggesting an important role for the social ecology of disease transmission in these rural communities.

METHODS

Two rural Thai-Lao villages that were part of a 12-village project in Northeastern Thailand were selected for detailed investigation of O. viverrini infection risk associated with sharing of raw fish dishes among households. The project included screening individuals for infection and cholangiocarcinoma, a household questionnaire, and offering treatment options for positive individuals. Social network mapping was used to construct raw fish dish-sharing networks and create a proxy variable capturing variability in the degree of food sharing (DFS), measured as the number of different households with which each household shared fish dishes. Measures of associations between DFS, O. viverrini infection, the frequency of raw fish consumption, and the number of raw fish dishes consumed were generated using binary logistic regression, proportional odds ordinal logistic regression, and Poisson regression.

RESULTS

The results showed that the probability that a household has members infected with O. viverrini increased by ~7% (P < 0.01) for each additional household included in its network. Moreover, the frequency and number of types of raw fish dishes consumed increased significantly as the DFS increased. Of the two villages, that with the highest infection prevalence (48% versus 34.6%) had significantly higher social connectivity overall (P < 0.001).

CONCLUSIONS

Our findings suggest that the social ecology of human settlements may be key to understanding the transmission dynamics of some FBT. In the case of O. viverrini in Thai-Lao communities, for which food sharing is a traditional practice supporting social cohesion, food sharing network mapping should be incorporated into community-based interventions. These should encourage fish dish preparation methods that minimize infection risk by targeting households with high DFS values.

Evolution of Socioeconomic Conditions and Its Relation to Spatial-Temporal Changes of Giardiasis and Helminthiasis in Amazonian Children

This study analyzed the evolution of socioeconomic, sanitary, and personal factors as well as spatiotemporal changes in the prevalence of helminthiasis and giardiasis in urban Amazonian children between 2003 and 2011. Child age, lack of sanitation, and lack of access to bottled water were identified as significant associated factors for helminthiasis and giardiasis. There was an overall improvement in socioeconomic and sanitary conditions in the city resulting in decreased helminth prevalences from 12.42 to 9.63% between 2003 and 2010, but the prevalence increased to 15.03% in 2011 due to migratory movement and unstable sanitary conditions. As for Giardiasis, socioeconomic and environmental changes were not enough to reduce prevalence (16% in 2003 and 23% in 2011). Spatial analysis identified a significant cluster for helminthiasis in an area of poor housing conditions. Control programs in the Amazon need to target high-risk areas focusing changes in sanitation, water usage, and health education.

Uncovering the Pathogenic Landscape of Helminth (Opisthorchis viverrini) Infections: A Cross-Sectional Study on Contributions of Physical and Social Environment and Healthcare Interventions

BACKGROUND

Helminth infections have proven recalcitrant to control by chemotherapy in many parts of Southeast Asia and indeed farther afield. This study isolates and examines the influence of different aspects of the physical and social environment, and uneven intervention effort contributing to the pathogenic landscape of human Opisthorchis viverrini infections.

METHODOLOGY

A cross-sectional survey, involving 632 participants, was conducted in four villages in northeast Thailand to examine the impact on prevalence and parasite burden of the reservoir dam environment, socio-economic, demographic, and behavioral factors, and health center intervention efforts. Formalin-ether concentration technique was used for diagnoses, and multivariate models were used for analyses.

PRINCIPAL FINDINGS

The importance attributed to O. viverrini infections varied among health centers in the four study villages. Villages where O. viverrini infections were not prioritized by the health centers as the healthcare focus were at a higher risk of infection (prevalence) with odds ratio (risk factor) of 5.73 (3.32-10.27) and p-value < 0.01. Priority of healthcare focus, however, did not appear to influence behavior, as the consumption of raw fish, the main source of O. viverrini infections in the study area, was 11.4% higher in villages that prioritized O. viverrini infections than those that did not (p-value = 0.01). Landscape variation, notably proximity to reservoir, affects vulnerability of local population to infection. Infection intensity was higher in population located closer to the reservoir with risk ratio of 2.09 (1.12-4.02) and p-value < 0.01. Patterns of infection intensities among humans were found to match fish infection intensity, where higher infection intensities were associated with fish obtained from the reservoir waterbody type (p-value = 0.023).

CONCLUSIONS/SIGNIFICANCE

This study demonstrated the importance of environmental influence and healthcare focus as risk factors of infections in addition to the socio-economic, demographic, and behavioral factors commonly explored in existing studies. The reservoir was identified as a crucial source to target for opisthorchiasis intervention efforts and the need to consider infection intensity in disease control efforts was highlighted. The holistic approach in this study, which underscores the close relationship between the environment, animals, and humans in development of human infections or diseases, is an important contribution to the framework of One Health approach, where consideration of helminth diseases has largely been overlooked.

Combining Footwear with Public Health Iconography to Prevent Soil-Transmitted Helminth Infections

Shoes are effective for blocking soil-transmitted helminths (STHs) that penetrate the skin. Unfortunately, shoe-wearing is uncommon in many areas where STHs are prevalent, in part because local populations are unaware of the health benefits of wearing shoes. This is especially true in low-literacy populations, where information dissemination through written messages is not possible. We launched a public health intervention that combines a public health image with sandals. The image is a "lenticular image" that combines two alternating pictures to depict the efficacy of shoes for preventing STH infection. This image is adhered to the shoe, such that the message is linked directly to the primary means of prevention. To create a culturally appropriate image, we conducted five focus group discussions, each with a different gender and age combination. Results of focus group discussions reinforced the importance of refining public health messages well in advance of distribution so that cultural acceptability is strong. After the image was finalized, we deployed shoes with the image in communities in western Uganda where hookworm is prevalent. We found that the frequency of shoe-wearing was 25% higher in communities receiving the shoes than in control communities. Microscopic analyses of fecal samples for parasites showed a sustained reduction in infection intensity for parasites transmitted directly through the feet when people received shoes with a public health image. Our results show that combining culturally appropriate images with public health interventions can be effective in low-literacy populations.

Integrated Healthcare Delivery: A Qualitative Research Approach to Identifying and Harmonizing Perspectives of Integrated Neglected Tropical Disease Programs

Background

While some evidence supports the beneficial effects of integrating neglected tropical disease (NTD) programs to optimize coverage and reduce costs, there is minimal information regarding when or how to effectively operationalize program integration. The lack of systematic analyses of integration experiences and of integration processes may act as an impediment to achieving more effective NTD programming. We aimed to learn about the experiences of NTD stakeholders and their perceptions of integration.

Methodology

We evaluated differences in the definitions, roles, perceived effectiveness, and implementation experiences of integrated NTD programs among a variety of NTD stakeholder groups, including multilateral organizations, funding partners, implementation partners, national Ministry of Health (MOH) teams, district MOH teams, volunteer rural health workers, and community members participating in NTD campaigns. Semi-structured key informant interviews were conducted. Coding of themes involved a mix of applying in-vivo open coding and a priori thematic coding from a start list.

Findings

In total, 41 interviews were conducted. Salient themes varied by stakeholder, however dominant themes on integration included: significant variations in definitions, differential effectiveness of specific integrated NTD activities, community member perceptions of NTD programs, the influence of funders, perceived facilitators, perceived barriers, and the effects of integration on health system strength. In general, stakeholder groups provided unique perspectives, rather than contrarian points of view, on the same topics. The stakeholders identified more advantages to integration than disadvantages, however there are a number of both unique facilitators and challenges to integration from the perspective of each stakeholder group.

Conclusions

Qualitative data suggest several structural, process, and technical opportunities that could be addressed to promote more effective and efficient integrated NTD elimination programs. We highlight a set of ten recommendations that may address stakeholder concerns and perceptions regarding these key opportunities. For example, public health stakeholders should embrace a broader perspective of community-based health needs, including and beyond NTDs, and available platforms for addressing those needs.

Neglected tropical diseases are a group of parasitic, viral, and bacterial diseases that are often co-endemic in low resource settings. Five of these diseases (lymphatic filariasis, onchocerciasis, schistosomiasis, soil transmitted helminths, and trachoma) are addressed specifically through a method called mass drug administration, where entire at risk populations are targeted with preventative drug treatments. Because of the geographical and interventional overlap between these diseases, many experts recommend program integration as a method for accelerating their control or elimination. However the optimal approaches for operationalizing integrated programing has not been systematically assessed. We undertook a cross sectional qualitative research study with neglected tropical disease stakeholders to understand different stakeholder approaches to and perspectives on program integration. The stakeholders highlighted different definitions of the term “integration”, the differential effectiveness of specific activities when integrated, the influence of integration on community member engagement, the influence of funders on integrated programming, facilitators and barriers to effective integration, and the effects of integration on health system strength. Our analysis suggests that there are three types of integration to consider: structural, process, and technical. We use these categories to make ten recommendations to stakeholders that might be used to improve integrated neglected tropical disease programming moving forward.

Prevalence of intestinal parasitic infections and associated risk factors among schoolchildren in the Plateau Central and Centre-Ouest regions of Burkina Faso

Background

Unsafe drinking water, unimproved sanitation and lack of hygiene pose health risks, particularly to children in low- and middle-income countries. This study aimed to assess the prevalence and risk factors of intestinal parasitic infections in school-aged children in two regions of Burkina Faso.

Methods

A cross-sectional survey was carried out in February 2015 with 385 children aged 8–14 years from eight randomly selected schools in the Plateau Central and Centre-Ouest regions of Burkina Faso. Stool samples were subjected to the Kato-Katz and a formalin-ether concentration method for the diagnosis of helminths and intestinal protozoa infections. Urine samples were examined with a urine filtration technique for Schistosoma haematobium eggs. Water samples from community sources (n = 37), children’s households (n = 95) and children’s drinking water cups (n = 113) were analysed for contamination with coliform bacteria and faecal streptococci. Data on individual and family-level risk factors were obtained using a questionnaire. Mixed logistic regression models were employed to determine factors associated with intestinal parasitic infections in schoolchildren.

Results

Intestinal parasitic infections were highly prevalent; 84.7 % of the children harboured intestinal protozoa, while helminth infections were diagnosed in 10.7 % of the children. We found significantly lower odds of pathogenic intestinal protozoa infection (Entamoeba histolytica/E. dispar and Giardia intestinalis) among children from the Plateau Central, compared to the Centre-Ouest region (P < 0.001). Children from households with “freely roaming domestic animals” (P = 0.008), particularly dogs (P = 0.016) showed higher odds of G. intestinalis, and children reporting exposure to freshwater sources through domestic chores had higher odds of S. haematobium infection compared to children without this water contact activity (P = 0.035). Water quality, household drinking water source and storage did not emerge as significant risk factors for intestinal parasitic infections in children.

Conclusions

Intestinal protozoa but not helminths were highly prevalent among schoolchildren in randomly selected schools in two regions of Burkina Faso. Our findings call for specific public health measures tailored to school-aged children and rural communities in this part of Burkina Faso. It will be interesting to assess the effect of water, sanitation and hygiene interventions on the transmission of intestinal parasitic infections.

Trial registration

ISRCTN17968589 (date assigned: 17 July 2015).

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-016-1835-4) contains supplementary material, which is available to authorized users.

Ivermectin Treatment and Sanitation Effectively Reduce Strongyloides stercoralis Infection Risk in Rural Communities in Cambodia

BACKGROUND

Strongyloides stercoralis is the only soil-transmitted helminth with the ability to replicate within its host, leading to long-lasting and potentially fatal infections. It is ubiquitous and its worldwide prevalence has recently been estimated to be at least half that of hookworm. Information on the epidemiology of S. stercoralis remains scarce and modalities for its large-scale control are yet to be determined.

METHODOLOGY/PRINCIPAL FINDINGS

A community-based two-year cohort study was conducted among the general population in a rural province in North Cambodia. At each survey, participants infected with S. stercoralis were treated with a single oral dose of ivermectin (200μg/kg BW). Diagnosis was performed using a combination of the Baermann method and Koga agar plate culture on two stool samples. The cohort included participants from eight villages who were either positive or negative for S. stercoralis at baseline. Mixed logistic regression models were employed to assess risk factors for S. stercoralis infection at baseline and re-infection at follow-up. A total of 3,096 participants were examined at baseline, revealing a S. stercoralis prevalence of 33.1%. Of these participants, 1,269 were followed-up over two years. Re-infection and infection rates among positive and negative participants at baseline were 14.4% and 9.6% at the first and 11.0% and 11.5% at the second follow-up, respectively. At follow-up, all age groups were at similar risk of acquiring an infection, while infection risk significantly decreased with increasing village sanitation coverage.

CONCLUSIONS/SIGNIFICANCE

Chemotherapy-based control of S. stercoralis is feasible and highly beneficial, particularly in combination with improved sanitation. The impact of community-based ivermectin treatment on S. stercoralis was high, with over 85% of villagers remaining negative one year after treatment. The integration of S. stercoralis into existing STH control programs should be considered without further delay.

Potential anthelmintic activity of Pelargonium endlicherianum Fenzl

ETHNOPHARMACOLOGICAL RELEVANCE

The decoction prepared from the roots of Pelargonium endlicherianum Fenzl. has been used for the treatment of gastrointestinal parasitism in small ruminants in Turkish Folk Medicine.

AIM OF THE STUDY

The aim of the present study is to investigate in vitro anthelmintic activity of the extracts prepared from the roots of Pelargonium endlicherianum Fenzl. (Geraniaceae).

MATERIALS AND METHODS

So as to determine the potential anthelmintic effect of the roots of the plant, n-hexane, ethyl acetate (EtOAc) and methanol (MeOH) extracts were successively prepared. In vitro test methods were used for the determination of the anthelmintic effect of the extracts on eggs, larvae and adults of Haemonchus contortus. The extracts were prepared in three increasing concentrations by using Phosphate Buffered Saline (PBS) for egg hatch, larval development assay and adult motility inhibition assay. PBS was used as negative control, levamisole (in PBS) was used as a reference.

RESULTS

The extracts exerted significant anthelmintic activity on three lifecycle stages of Haemonchus contortus when compared to the negative control group (P<0.05). The activity was proportional to the concentrations of the plant extracts for egg hatching and the first stage larvae but not for the adult worms. Moreover, the results have shown that the MeOH extract was found to have higher ovicidal and larvicidal effects than the other extracts.

CONCLUSIONS

Results of the present research have revealed that MeOH extract obtained from P. endlicherianum demonstrated in vitro anthelmintic effect against the eggs, the first stage larvae and the adult stage of H. contortus. These results confirmed the folkloric use of the plant. It was suggested that the tannin content of the plant could be responsible for the anthelmintic activity.

Ascaris and hookworm transmission in preschool children in rural Panama: role of subsistence agricultural activities

This longitudinal study explored whether aspects of subsistence agriculture were associated with presence and intensity of Ascaris and hookworm in preschool children in rural Panama. Questionnaires were used to collect data on household socio-demographics, child exposure to agriculture and household agricultural practices. Stool samples were collected from children (6 months–5 years) at 3 time points, with albendazole administered after each to clear infections, resulting in 1 baseline and 2 reinfection measures. A novel Agricultural Activity Index (AAI) was developed using principal components analysis to measure the intensity of household agricultural practices. Zero-inflated negative binomial regression models revealed baseline hookworm egg counts were higher if children went to the agricultural plot and if the plot was smaller. Baseline and reinfection Ascaris egg counts were higher if children went to the plot and households had higher AAI, and higher at baseline if the plot was smaller. Caregiver time in the plot was negatively associated with baseline Ascaris egg counts, but positively associated with baseline hookworm and Ascaris reinfection egg counts. Children who spent more time playing around the home were less likely to be infected with Ascaris at baseline. We conclude that preschool child exposure to subsistence agriculture increased Ascaris and hookworm intensity.

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.

Demographic, socioeconomic and environmental changes affecting circulation of neglected tropical diseases in Egypt

Egypt has been plagued by many neglected tropical diseases since Pharaonic time. These diseases are Schistosomiasis, soil-transmitted helminthiasis, lymphatic filariasis, leishmaniasis and fascioliasis beside the epidermal parasitic skin diseases. Indeed, theses diseases still persist as public health problem in the country by the influence of demographic, socioeconomic and environmental obstacles. This study seeks for understanding the contribution of each factor in each obstacle in neglected tropical diseases perpetuation which in turn could help the governorate in planning integrated control strategies. It was found that poverty, unregulated urbanization and inadequate sanitation are important socioeconomic factors that have great effect on the transmission dynamics of the diseases. The environmental factors which affect the epidemiology of these diseases in the country are scarcity of water, construction of dams, land reclamation for agriculture beside the climate factors. Unfortunately, the panic increase in the population growth rate minimizes the efforts done by the governorate to elevate the public health services. These conditions also affect the transmission of epidermal parasitic skin diseases including scabies, head lice and hookworm-related cutaneous larva migrans. The control programs and the recommendations to combat the diseases were discussed. The present study showed that the ecological factors affecting each neglected tropical disease in Egypt are somewhat similar which makes it worthy to develop an integrated control approaches aiming at improving the leading factors of neglected tropical diseases circulation in the country.

Anthelmintic activity of trans-cinnamaldehyde and A- and B-type proanthocyanidins derived from cinnamon (Cinnamomum verum)

Cinnamon (Cinnamomum verum) has been shown to have anti-inflammatory and antimicrobial properties, but effects on parasitic worms of the intestine have not been investigated. Here, extracts of cinnamon bark were shown to have potent in vitro anthelmintic properties against the swine nematode Ascaris suum. Analysis of the extract revealed high concentrations of proanthocyanidins (PAC) and trans-cinnamaldehyde (CA). The PAC were subjected to thiolysis and HPLC-MS analysis which demonstrated that they were exclusively procyanidins, had a mean degree of polymerization of 5.2 and 21% of their inter-flavan-3-ol links were A-type linkages. Purification of the PAC revealed that whilst they had activity against A. suum, most of the potency of the extract derived from CA. Trichuris suis and Oesophagostomum dentatum larvae were similarly susceptible to CA. To test whether CA could reduce A. suum infection in pigs in vivo, CA was administered daily in the diet or as a targeted, encapsulated dose. However, infection was not significantly reduced. It is proposed that the rapid absorption or metabolism of CA in vivo may prevent it from being present in sufficient concentrations in situ to exert efficacy. Therefore, further work should focus on whether formulation of CA can enhance its activity against internal parasites.

The roles of water, sanitation and hygiene in reducing schistosomiasis: a review

Schistosomiasis is a disease caused by infection with blood flukes of the genus Schistosoma. Transmission of, and exposure to, the parasite result from faecal or urinary contamination of freshwater containing intermediate host snails, and dermal contact with the same water. The World Health Assembly resolution 65.21 from May 2012 urges member states to eliminate schistosomiasis through preventive chemotherapy (i.e. periodic large-scale administration of the antischistosomal drug praziquantel to school-aged children and other high-risk groups), provision of water, sanitation and hygiene (WASH) and snail control. However, control measures focus almost exclusively on preventive chemotherapy, while only few studies made an attempt to determine the impact of upgraded access to safe water, adequate sanitation and good hygiene on schistosome transmission. We recently completed a systematic review and meta-analysis pertaining to WASH and schistosomiasis and found that people with safe water and adequate sanitation have significantly lower odds of a Schistosoma infection. Importantly though, the transmission of schistosomiasis is deeply entrenched in social-ecological systems, and hence is governed by setting-specific cultural and environmental factors that determine human behaviour and snail populations. Here, we provide a comprehensive review of the literature, which explores the transmission routes of schistosomes, particularly focussing on how these might be disrupted with WASH-related technologies and human behaviour. Additionally, future research directions in this area are highlighted.

Toward integrated opisthorchiasis control in northeast Thailand: the Lawa project

Human liver fluke, Opisthorchis viverrini, a food-borne trematode is a significant public health problem in Southeast Asia, particularly in Thailand. Despite a long history of control programmes in Thailand and a nationwide reduction, O. viverrini infection prevalence remains high in the northeastern provinces. Therefore, a new strategy for controlling the liver fluke infection using the EcoHealth/One Health approach was introduced into the Lawa Lake area in Khon Kaen province where the liver fluke is endemic. A programme has been carried using anthelminthic treatment, novel intensive health education methods both in the communities and in schools, ecosystem monitoring and active community participation. As a result, the infection rate in the more than 10 villages surrounding the lake has declined to approximate one third of the average of 50% as estimated by a baseline survey. Strikingly, the Cyprinoid fish species in the lake, which are the intermediate host, now showed less than 1% prevalence compared to a maximum of 70% at baseline. This liver fluke control programme, named "Lawa model," is now recognised nationally and internationally, and being expanding to other parts of Thailand and neighbouring Mekong countries. Challenges to O. viverrini disease control, and lessons learned in developing an integrative control programme using a community-based, ecosystem approach, and scaling-up regionally based on Lawa as a model are described.

Integrated control programmes for schistosomiasis and other helminth infections in P.R. China

The prevalence of human schistosomiasis and soil-transmitted helminthiasis (STH) has decreased significantly in the People's Republic of China (P.R. China), particularly after 2005 when the national control programmes were reinforced by forming of integrated control strategies. Furthermore, social-economic development also contributed to the decrease of schistosome and soil-transmitted helminth infections. The prevalence of the zoonotic helminthiasis, including clonorchiasis and echinococcosis, on the other hand, is either underestimated or has in fact increased due to changes in social and environmental factors. In comparison with the control strategies in force and their effects on those four kinds of helminthiasis, the challenges and control priorities for the potential transfer from control to elimination of each disease is reviewed, to provide evidence for policy-makers to act upon.

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.

The relationship between water, sanitation and schistosomiasis: a systematic review and meta-analysis

Background

Access to “safe” water and “adequate” sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review.

Methodology

We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I².

Principal Findings

Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR) = 0.53, 95% confidence interval (CI): 0.47–0.61). Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47–0.73) and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57–0.84). Included studies were mainly cross-sectional and quality was largely poor.

Conclusions/Significance

Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human behavior, and schistosome transmission.

Schistosomiasis is a serious disease in many developing countries, and the control of schistosomiasis relies on the large-scale administration of praziquantel. However, this strategy fails to address the root causes of schistosomiasis, which people acquire during contact with freshwater bodies that contain infected snails. It is suggested that improving access to clean water and sanitation reduces the risk of schistosomiasis transmission. Moreover, the use of soap, detergent, and endod (a berry sometimes used as a substitute for soap) might kill snails and the parasite larvae they excrete. We systematically reviewed the literature and performed a meta-analysis to study the association between people's access to clean water, sanitation, and good hygiene and the risk of schistosomiasis. People with access to clean water and adequate sanitation were at lower risks of schistosomiasis. No studies were found to explore the relationship between hygiene and risk of schistosomiasis. The difference in infection rates between people with and without access to clean water and sanitation varies widely between studies, suggesting that the impact of water and sanitation on schistosomiasis transmission is mediated by many other social and environmental factors. Further research is needed on the impact of water, sanitation and hygiene interventions for schistosomiasis control.

High Schistosoma mansoni disease burden in a rural district of western Zambia

Schistosoma mansoni disease is endemic in most parts of rural Zambia, and associated complications are common. We conducted a cross-sectional study among 754 people in rural communities of Kaoma District, western Zambia to determine the burden of S. mansoni infection and associated morbidity. Parasitology and ultrasonography assessments were conducted on consenting participants. The overall prevalence of S. mansoni infection and geometric mean egg count (GMEC) were 42.4% (304) and 86.6 eggs per gram (95% confidence interval = 75.6-99.6), respectively. Prevalence was highest in the age group of 15-19 years old (adjusted prevalence ratio = 1.70, P = 0.017). S. mansoni-related portal fibrosis was detected in 26% of the participants screened. Participants above 39 years old were 2.93 times more likely to have fibrosis than the 7-9 years old age group (P = 0.004). The study highlights the high burden of S. mansoni disease in this area and calls for immediate interventions to avert complications associated with the disease.

Controlling parasites, understanding practices: the biosocial complexity of a One Health intervention for neglected zoonotic helminths in northern Lao PDR

A parasitological survey in northern Lao PDR showed a remote ethnic minority village to be hyper-endemic for Taenia solium, a Neglected Tropical Disease (NTD) that impacts human and pig health. An intervention combining human Mass Drug Administration (MDA) with porcine vaccination and antihelmintic treatment was then implemented, targeting both T. solium and other soil-transmitted helminths. To understand the biosocial complexity of this integrated One Health intervention, we conducted a rapid ethnographic study exploring the transmission dynamics of T. solium and locally acceptable long-term control options. Informed by two years of project work in the village, this included six focus group discussions, 35 semi-structured interviews, a latrine survey, a school-based education meeting, participant observation and many unstructured interviews conducted over two weeks in October 2013. We found that risk behaviours were mediated by various social determinants including limited market access, interrelationships between alcohol, ancestral sacrifices and the consumption of raw pork, seasonal variations and poor latrine coverage. Only sixteen percent of households had latrines, attributed to the unacceptability of dry latrines, lack of water access, poor building techniques and poverty. Whilst women could explain T. solium transmission, most men and children could not, revealing that distributed posters/leaflets relied too heavily on text and ambiguous images. Compliance with MDA was high due to trust between project staff and village leaders. However understandings of pharmacology, minor side effects, human migration and children's fear of worms may lead to resistance in future programmes. Our research highlights the complexities of controlling T. solium and other soil-transmitted helminths in a remote ethnic minority village and the need to integrate biomedical and participatory approaches. Although we showcase the heuristic value of using rapid ethnography to inform intervention strategies as part of a One Health/NTD agenda, we also identify several possible paradoxes and conundrums in embedding locally-grounded biosocial analysis into NTD programmes. These need to be acknowledged and negotiated by multidisciplinary teams.