Control Of Soil-transmitted Helminthiasis Research Articles

Lymphatic filariases and soil-transmitted helminthiases in Sri Lanka: the challenge of eliminating residual pockets of transmission.

Sri Lanka has successfully met the challenge of controlling both lymphatic filariasis (LF) and soil-transmitted helminthiases (STH) as public health problems. The primary public health strategy for combatting both conditions has been preventive chemotherapy. The national programme for the elimination of LF implemented five annual rounds of mass chemotherapy in the endemic districts from 2002 to 2006 using a combination of diethylcarbamazine and albendazole. The overall microfilaria rate declined from 0.21% in 2001 before the mass chemotherapy, to 0.06% in 2016, at declaration of elimination of LF as a public health problem by the World Health Organization. Currently Sri Lanka is in the phase of post-validation surveillance. Achieving control of STH has been more difficult. Mass deworming programmes have been implemented for nearly a century, and national-level surveys reported prevalence rates declining from 6.9% in 2003 to 1% in 2017. However, neither of these infections has been completely eliminated. A situation analysis indicates continued transmission of both among high-risk communities. This paper explores the reasons for persistence of transmission of both LF and STH in residual pockets and the measures that are required to achieve long-term control, or perhaps even interrupt transmission in Sri Lanka. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.

Integration of Monitoring for Parasitologic Status for Schistosomiasis and Soil-transmitted Helminthiasis Control Programs with Nutritional Status of Pre-school and School Age Children in Selected Municipalities in Northern Leyte, the Philippines

The periodic collection of parasitologic and morbidity indicators is recommended by the World Health Organization (WHO) to monitor schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) control programs. In 2017, the DOH-CHD VIII (Department of Health–Center for Health Development Region 8 Office) – in collaboration with UP-NTDSG (the University of the Philippines Neglected Tropical Diseases Study Group) – conducted a monitoring activity aimed at determining [1] the prevalence and intensity of SCH and STH; [2] seroprevalence of SCH; and [3] prevalence of stunting, underweight, wasting, and anemia in pre-school-age children (PSAC) and school-age children (SAC) in selected municipalities in the province of Northern Leyte, the Philippines as part of monitoring the local implementation of SCH and STH control programs. Stool samples were collected, processed using the Kato-Katz technique, and examined through microscopy. Blood specimens collected from SAC were tested for the presence of Schistosoma japonicum antibody using the IgG ELISA (enzyme-linked immunosorbent assay) kit. Data on anthropometric measurements and hemoglobin levels were collected with adherence to WHO guidelines. Secondary analysis of the gathered data showed that SCH prevalence in SAC was 3.1%, but SCH seroprevalence was 83.1%. Although STH prevalence met the national target of < 50%, heavy-intensity STH prevalence remained higher than the global target of < 2%. The overall prevalence of underweight, stunting, and wasting were 19.2, 38.0, and 10.6%, respectively. STH was significantly associated with stunting in PSAC (p = 0.030) and anemia in SAC (p = 0.033). The monitoring activity demonstrated the utility of an integrated monitoring scheme for SCH and STH control programs and nutrition programs at the local level. This model can be adopted for optimization and utilization by national programs for monitoring and may likewise benefit local government units for purposes of policy and planning.

Accessibility of Soil-transmitted Helminthiasis Control Strategies in Selected Indigenous People Communities in the Philippines

Background. Indigenous peoples (IPs) remain vulnerable to soil-transmitted helminthiasis (STH) due to limited access to sanitary toilets, clean water, quality health education, and services. The World Health Organization recommends periodic mass drug administration (MDA) of anthelminthics, health education, and improvements in water, sanitation, and hygiene (WASH) as control strategies to reduce morbidities caused by STH in target populations such as schoolage children (SAC). This paper complements the published results of the parasitological survey (prevalence and intensity of STH)conducted in selected Aeta and Ata-Manobo communities. Objectives. This study aimed to describe the accessibility of STH control strategies to respond to the needs of SAC in IP communities in Pampanga and Davao del Norte, the Philippines. It likewise intended to describe access of these IP communities to STH control strategies. Methods. Data on accessibility of and access to STH control strategies were collected using key informant interviews (KIIs) and focus group discussions (FGDs). Eleven officials and workers from the departments of health and education, local government units, and two IP leaders were interviewed on the existing STH burden in SAC, implementation of STH control strategies, particularly of MDA, health education campaigns, and improvements in WASH including good practices and challenges in program implementation. Three FGDs with parents, elementary school teachers of IP schools, and rural health midwives were conductedseparately. Guide questions focused on accessibility of and access to STH prevention and control strategies for SAC in IP communities. Informed consent to conduct and record KIIs and FGDs were obtained from participants prior to participation.Analysis of a multi-disciplinary team was based on the accessibility framework for IPs accessing indigenous primary health care services by Davy et al. (2016). Results. The characteristics of the STH control strategies and the target populations are interrelated factors thatinfluence accessibility. Challenges in the availability of the MDA program, particularly, inadequate staffing, drugshortages, and delays in delivery affect accessibility of and access to the free STH control strategies. Perceivedharm, adverse events, stigma, beliefs, and practices likewise affect access. Lack of information on the similarity of treatment through community- and schoolbased MDA programs also affected engagement of SAC. IP communities are special settings where geographic isolation, peace and order situation as well as watersupply need to be considered to help ensure access to STH control strategies, high MDA coverage, andimprovements in WASH leading to desired outcomes. Conclusions. Considering the context of IP communities and addressing the challenges in the accessibility of and access to STH control strategies are necessary to ensure successful implementation of an integrated approach in STH prevention and control strategies. Challenges in the accessibility of STH control strategies are inadequate staffing, poor inventory, and delays in the delivery of drugs, as well as poor sanitation and hygiene. Access of SAC is likewise affected by misconceptions on safety and efficacy of anthelminthics, including stigma and cultural practices. The similarity of the MDA programs based in school or community need to be disseminated. &nbsp

Comparison of coproprevalence and seroprevalence to guide decision-making in national soil-transmitted helminthiasis control programs: Ethiopia as a case study.

BackgroundWHO recommends periodical assessment of the prevalence of any soil-transmitted helminth (STH) infections to adapt the frequency of mass drug administration targeting STHs. Today, detection of eggs in stool smears (Kato-Katz thick smear) remains the diagnostic standard. However, stool examination (coprology) has important operational drawbacks and impedes integrated surveys of multiple neglected tropical diseases. Therefore, the aim of the present study was to assess the potential of applying serology instead of coprology in STH control program decision-making.MethodologyAn antibody-ELISA based on extract of Ascaris lung stage larvae (AsLungL3-ELISA) was applied in ongoing monitoring activities of the Ethiopian national control program against schistosomiasis and soil-transmitted helminthiasis. Blood and stool samples were collected from over 6,700 students (median age: 11) from 63 schools in 33 woredas (districts) across the country. Stool samples of two consecutive days were analyzed applying duplicate Kato-Katz thick smear.Principal findingsOn woreda level, qualitative (seroprevalence) and quantitative (mean optical density ratio) serology results were highly correlated, and hence seroprevalence was chosen as parameter. For 85% of the woredas, prevalence based on serology was higher than those based on coprology. The results suggested cross-reactivity of the AsLungL3-ELISA with Trichuris. When extrapolating the WHO coproprevalence thresholds, there was a moderate agreement (weighted κ = 0.43) in program decision-making. Using the same threshold values would predominantly lead to a higher frequency of drug administration.SignificanceThis is the first time that serology for soil-transmitted helminthiasis is applied on such large scale, thereby embedded in a control program context. The results underscore that serology holds promise as a tool to monitor STH control programs. Further research should focus on the optimization of the diagnostic assay and the refinement of serology-specific program decision-making thresholds.

A prevalence-based transmission model for the study of the epidemiology and control of soil-transmitted helminthiasis.

Much effort has been devoted by the World Health Organization (WHO) to eliminate soil-transmitted helminth (STH) infections by 2030 using mass drug administration targeted at particular risk groups alongside the availability to access water, sanitation and hygiene services. The targets set by the WHO for the control of helminth infections are typically defined in terms of the prevalence of infection, whereas the standard formulation of STH transmission models typically describe dynamic changes in the mean-worm burden. We develop a prevalence-based deterministic model to investigate the transmission dynamics of soil-transmitted helminthiasis in humans, subject to continuous exposure to infection over time. We analytically determine local stability criteria for all equilibria and find bifurcation points. Our model predicts that STH infection will either be eliminated (if the initial prevalence value, y(0), is sufficiently small) or remain endemic (if y(0) is sufficiently large), with the two stable points of endemic infection and parasite eradication separated by a transmission breakpoint. Two special cases of the model are analysed: (1) the distribution of the STH parasites in the host population is highly aggregated following a negative binomial distribution, and (2) no density-dependent effects act on the parasite population. We find that disease extinction is always possible for Case (1), but it is not so for Case (2) if y(0) is sufficiently large. However, by introducing stochastic perturbation into the deterministic model, we discover that chance effects can lead to outcomes not predicted by the deterministic model alone, with outcomes highly dependent on the degree of worm clumping, k. Specifically, we show that if the reproduction number and clumping are sufficiently bounded, then stochasticity will cause the parasite to die out. It follows that control of soil-transmitted helminths will be more difficult if the worm distribution tends towards clumping.

Can Moxidectin Be an Anthelmintic Alternative for Trichuris trichiura and Strongyloides stercoralis: A Systematic Review.

Strongyloides stercoralis and Trichuris trichiura parasitic infections are two of the many neglected tropical diseases. These parasitic infections are of considerable public health relevance, particularly in resource-limited countries. Moxidectin, a well-established drug in veterinary medicine, is now a Food and Drug Administration (FDA) approved medication for human onchocerciasis. For the past five years, this medication has been under clinical trials to evaluate its efficacy and safetiness in other helminthic infections. Moxidectin might complement the already existing treatment and control of soil-transmitted helminthiasis (STH). Therefore, we systematically reviewed existing human interventional studies to evaluate the efficacy and safety of this medication when administered alone or in combination with other antiparasitic medications in order to achieve a cure.

Community-wide prevalence and intensity of soil-transmitted helminthiasis and Schistosoma mansoni in two districts of Sierra Leone.

In Sierra Leone, nationally powered school-based surveys have documented significant progress in the control of soil-transmitted helminthiasis (STH) and schistosomiasis. In order to assess the district-level prevalence and intensity of infection among key at-risk groups outside of school age children (SAC), we conducted a multi-stage, cluster-sample household survey in Bo and Kenema districts in May 2018. From both districts, we examined 1,282 pre-school age children (PSAC), 730 school age children (SAC), and 517 adults over 14 years (including 387 women of reproductive age, or WRA) for STH and Schistosoma mansoni infection using Kato Katz technique. In Bo, STH prevalence was 8.0% (95% Upper Confidence Limit 10.2%) in PSAC, 6.4% (95% Upper Confidence Limit 9.0%) in SAC, 14.1% (95% Upper Confidence Limit 17.4%) in all adults and 11.9% (95% Upper Confidence Limit 17.4%) in WRA. In Kenema, STH prevalence was 18.1% (95% Upper Confidence Limit 20.5%) in PSAC, 17.3% (95% Upper Confidence Limit 20.7%) in SAC, and 16.9% (95% Upper Confidence Limit 20.5%) in all adults and 16.9% (95% Upper Confidence Limit 22.6%) in WRA. Hookworm species were the most prevalent of STH in both districts overall. The overall prevalence of S. mansoni was <10% in Bo and <20% in Kenema, and was similar across age groups. No moderate or heavy intensity STH infections or heavy intensity S. mansoni infections, as per World Health Organization (WHO) classification, were detected in either district. Sanitation variables, such as toilet access and quality, were independently associated with STH and S. mansoni infection. In Kenema, STH prevalence in SAC was within the WHO-defined range for annual treatment, whereas a previous nationally-powered survey estimated it to lie within the range of treatment once per two years. By utilizing community-based sampling, we were able to assess prevalence among WRA and make recommendations based on current guidance from WHO. To continue toward elimination of STH and S. mansoni as a public health problem, resources should be mobilized to increase access to and uptake of improved sanitation at community and household levels.

Досвід проведення дегельмінтизації у дітей

Актуальність проблеми лікування паразитозів не викликає сумнівів. Всесвітня організація охорони здоров’я включила боротьбу з геогельмінтозами у Глобальну стратегію розвитку. Наше дослідження світової літератури підтвердило значну поширеність гельмінтозів і їх негативний вплив на здоров’я та розвиток дітей. Метою нашого дослідження було визначення ефективності комплексного підходу до дегельмінтизації дітей віком від 3 років препаратами альбендазолу та сорбентом. Проведення дегельмінтизації альбендазолом виявилося ефективним, а доповнення терапії сорбентом сприяло швидкому зменшенню проявів гельмінтозу.

Schistosomiasis and Soil-transmitted Helminthiasis Morbidity Control in Selected Communities in Eastern Visayas, Philippines: Post Haiyan

Objective. As part of the evaluation of control programs recommended by WHO, this study describes the local implementation of schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) morbidity control as well as water, sanitation, and hygiene (WASH) interventions post calamity. It likewise determines the challenges, areas for improvement, and good practices in SCH and STH morbidity control strategies in Haiyan-stricken areas in Eastern and Western Samar, the Philippines. Methods. Twenty key informant interviews and eight focus group discussions documented the implementation of SCH and STH control strategies in Eastern Visayas. Data analysis was done manually by a multi-disciplinary team. Results. Mass drug administration (MDA) in schools and communities was conducted for morbidity control. MDA for STH for pre-school-age children was integrated into the Garantisadong Pambata program, while a school-based teacher-assisted approach was used for school-age children. WASH facilities, such as sanitary toilets, were constructed through the initiatives of the local government units (LGUs) and other private sectors. Partnerships with Plan International Philippines helped in the implementation of WASH through the conduct of Community-led Total Sanitation. Health advocacies helped instill behavioral change in the community. SCH surveillance was conducted annually while STH surveillance was irregularly implemented. Data on MDA coverage were validated through Rapid Coverage Assessment before final reporting. Discrepancies were observed due to typographical errors and the inclusion of teachers and transient migrants in the reports submitted. Challenges in the implementation of MDA include delays in drug delivery, lack of human resources, non-compliance of participants, and drug unpalatability. Challenges in WASH included the lack of hand washing facilities, inaccessibility to safe water, as well as non-utility of sanitary toilets. Strengthening health advocacy and education may help address these challenges. Conclusion. The involvement and partnership of various stakeholders such as LGUs, WASH, and veterinary sectors, together with the academe are needed to strengthen and enhance the implementation of SCH and STH control activities. An integrated approach may contribute to improvements in SCH and STH prevention and control of the communities in selected Haiyan-stricken areas.

Assessment of the required performance and the development of corresponding program decision rules for neglected tropical diseases diagnostic tests: Monitoring and evaluation of soil-transmitted helminthiasis control programs as a case study.

Recently, the World Health Organization established the Diagnostic Technical Advisory Group to identify and prioritize diagnostic needs for neglected tropical diseases, and to ultimately describe the minimal and ideal characteristics for new diagnostic tests (the so-called target product profiles (TPPs)). We developed two generic frameworks: one to explore and determine the required sensitivity (probability to correctly detect diseased persons) and specificity (probability to correctly detect persons free of disease), and another one to determine the corresponding samples sizes and the decision rules based on a multi-category lot quality assurance sampling (MC-LQAS) approach that accounts for imperfect tests. We applied both frameworks for monitoring and evaluation of soil-transmitted helminthiasis control programs. Our study indicates that specificity rather than sensitivity will become more important when the program approaches the endgame of elimination and that the requirements for both parameters are inversely correlated, resulting in multiple combinations of sensitivity and specificity that allow for reliable decision making. The MC-LQAS framework highlighted that improving diagnostic performance results in a smaller sample size for the same level of program decision making. In other words, the additional costs per diagnostic tests with improved diagnostic performance may be compensated by lower operational costs in the field. Based on our results we proposed the required minimal and ideal diagnostic sensitivity and specificity for diagnostic tests applied in monitoring and evaluating of soil-transmitted helminthiasis control programs.

Transmission of Soil Transmitted Helminthiasis in the Mifi Health District (West Region, Cameroon): Low Endemicity but Still Prevailing Risk

The control of soil-transmitted helminthiasis (STH) in Cameroon is focused on large-scale deworming through annual mass drug administration (MDA) of albendazole or mebendazole to at-risk groups, principally pre-school and school-age children. After a decade of intervention, prevalence and intensity of infection have been significantly lowered, encouraging the paradigm shift from control to elimination. However, STH eggs are extremely resistant to environmental stressors and may survive for years in soils. It therefore appeared important to assess whether the risk of transmission was still prevailing, especially in a context where transmission of soil-transmitted helminths in the human population had almost been interrupted. A retrospective and a prospective cross-sectional surveys were conducted in five Health Areas of the Mifi Health District (West Region, Cameroon) to: (i) assess the trends in infestation rates over three-years (2018–2020) using health facility registers, and (ii) investigate, in 2020, the contamination rates of the environment by dissemination stages of soil-transmitted helminths using the sucrose centrifugal flotation method. The overall soil-transmitted helminth infestation rate was 4.9% (95% CI: 4.3–5.6), significantly lower than the overall soil contamination rate (12.0%; 95% CI: 8.2–17.2). These results are supportive of the low endemicity level of STHs in the Mifi Health District, but environmental pollution by dissemination stages of the parasites outlines that the risk of transmission is still persistent. It therefore appears compulsory to account for the environment when considering policy/recommendations for transmission interruption and stopping MDA, as it is in the case with vector-borne diseases.

Survey Design to Monitor Drug Efficacy for the Control of Soil-Transmitted Helminthiasis and Schistosomiasis.

BackgroundControl of soil-transmitted helminthiasis and schistosomiasis relies heavily on regular preventive chemotherapy. Monitoring drug efficacy is crucial to provide early warning of treatment failures. The World Health Organization (WHO) recommends a survey design in which only egg-positive individuals are retested after treatment. Although this practice makes more efficient use of resources, it may lead to biased drug efficacy estimates.MethodsWe performed a simulation study to assess the potential for bias when evaluating drug efficacy using the World Health Organization–recommended survey design, and to identify alternative designs for evaluating drug efficacy that are less affected by bias. These designs were also based on selection of egg-positive individuals, but involve retesting them a second time at baseline and up to 2 times at follow-up. The utility of the different designs was compared fairly by constraining them to the same budget.ResultsThe standard procedure of selecting egg-positive individuals can introduce a substantial positive bias in drug efficacy due to regression toward the mean, particularly when infection levels or drug efficacy are low. This bias was completely eliminated by using a second baseline sample, conditionally on the first sample being excluded from analysis. Precision of estimates can be improved by increasing the number of thick smears and/or samples per person at follow-up, despite fewer individuals being tested within the same budget.ConclusionsWe present optimized survey designs to monitor drug efficacy in field settings, which are highly relevant for sustained control of soil-transmitted helminths and schistosomiasis, as well as onchocerciasis and lymphatic filariasis.

The impact of Worms and Ladders, an innovative health educational board game on Soil-Transmitted Helminthiasis control in Abeokuta, Southwest Nigeria.

In most endemic sub-Saharan African countries, repeated infections with soil-transmitted helminth (STH) occur as early as six weeks after the end of mass drug administration (MDA) with albendazole. In this study, we designed a new health educational board game Worms and Ladders and evaluated its potential to complement MDA with albendazole and reduce reinfection rates through the promotion of good hygiene practices among school-aged children. The evaluation employed a randomized control trial (RCT) design. Baseline knowledge, attitude and practices (KAP) relating to STH were obtained using a questionnaire from 372 pupils across six schools in Abeokuta, Nigeria. Schools were randomly assigned into intervention and control group, with the former and latter receiving Worms and Ladders and the common Snake and Ladder board game respectively. Fresh stool samples were also collected at baseline for STH diagnosis before administering 400mg single dose albendazole. Follow-up assessments of STH burden and KAP were conducted three and six months' post-intervention. Data generated from the study were analyzed using SPSS 20.0 software, with confidence interval set at 95%. Prevalence of STH dropped from 25.0% to 10.4% in the intervention group and 49.4% to 33.3% in the control group at three months' post-intervention. The prevalence further dropped to 5.6% in the intervention group at six months' post-intervention. However, it increased to 37.2% in the control group at six months' post-intervention. There was a significant difference (p<0.05) in prevalence after intervention among the groups. KAP on transmission, control and prevention of STH significantly improved (p<0.05) from 5.2% to 97.9% in the intervention group compared to 6.2% to 7.1% in the control group. The Worms and Ladders board game shows the potential to teach and promote good hygiene behavior among SAC. These findings posit the newly developed game as a reliable tool to complement mass drug administration campaigns for STH control.

Soil-transmitted helminthiasis in four districts in Bangladesh: household cluster surveys of prevalence and intervention status

BackgroundIn 2016, after 8 years of twice-annual nationwide preventive chemotherapy (PC) administration to school-age children (SAC), the Bangladesh Ministry of Health & Family Welfare (MOHFW) sought improved impact and intervention monitoring data to assess progress toward the newly adopted goal of eliminating soil-transmitted helminthiasis (STH) as a public health problem.MethodsWe surveyed four Bangladeshi districts between August and October 2017. We conducted a multi-stage, cluster-sample, household survey which produced equal-probability samples for preschool-age children (PSAC; 1–4 years), SAC (5–14 years), and adults (≥ 15 years). Standardized questionnaires were administered, using Android-based smart phones running an Open Data Kit application. Stool samples were collected and testing for STH prevalence and infection intensity used the Kato-Katz technique.ResultsIn all, 4318 stool samples were collected from 7164 participants. Estimates of STH prevalence by risk group in three of the four surveyed districts ranged from 3.4 to 5.0%, all with upper, 1-sided 95% confidence limits < 10%. However, STH prevalence estimates in Sirajganj District ranged from 23.4 to 29.1%. Infections in that district were spatially focal; four of the 30 survey clusters had > 50% prevalence in at least one risk group. Among all tested specimens, Ascaris lumbricoides was the most common STH parasite [8.2% (n = 352)], followed by Trichuris trichiura [0.9% (n = 37)], and hookworm [0.6% (n = 27)]. In each district, PC coverage among SAC was above the 75% program target but did not exceed 45% among PSAC in any district. Improved sanitation at home, school, or work was over 90% in all districts.ConclusionsIn the three low-prevalence districts, the MOHFW is considering decreasing the frequency of mass drug administration, per World Health Organization (WHO) guidelines. Also, the MOHFW will focus programmatic resources and supervisory efforts on Sirajganj District. Despite considering WHO guidance, the MOHFW will not expand PC administration to women of reproductive age partly due to the low prevalence of hookworm and T. trichiura, the STH parasites that contribute most to morbidity in that risk group. Data collected from surveys such as ours would help effectively guide future STH control efforts in Bangladesh and elsewhere.

Engagement of the National Institute of Parasitic Diseases in control of soil-transmitted helminthiasis in China.

Soil-transmitted helminthiases (STHs) have been widely transmitted in China and the control of STHs was initiated by NIPD-CTDR since its foundation. Three national surveys on STHs have been carried out in China, and the infection rate has dropped from 53.58% in the first national survey (1988-92) to 4.49% in the third national survey (2014-16) due to strong interventions including mass drug administration, health education and environment improvement. National surveillance of STHs started in 2006 and has been implemented successively until now, which allows to understand the endemic status and trends of STHs prevalence in China. Surveillance has been expanded to 30 provinces of China since 2016. Integrated pilot programmes have been implemented between 2006 and 2009, in which an integrated strategy, with health education and control of infection sources as key components, was adopted. Since 2019, new control pilots have been started, which will be continued for five successive years to further explore appropriate control strategies in the current "new era". With the decline of infection rate of STHs, China is approaching the elimination stage for STHs. In order to achieve this final target, poverty alleviation programmes should be integrated with precise control measures, according to real situations.

Soil-Transmitted Helminthiasis — China, 2018

What is already known about this topic? Soil-transmitted helminthiasis (STH) is distributed widely in China and a large number of the population is afflicted. However, trends of STH infections are decreasing. What is added by this report? The most recent data indicates that the overall prevalence of STH was 1.29% in 2018 in China, which was based on the national sentinel surveillance and demonstrates a continuous decline pattern. What are the implications for public health practice? Considering the current prevalence in China and various endemic statuses in different regions, precision control measures should be implemented for the control and elimination of STH in China.

Gaps and barriers in interventions for the control of soil-transmitted helminthiasis among school-age children in an endemic area of the Philippines: a school-based point-of-view.

We used a qualitative cross-sectional study in 20 elementary schools in an area of Cagayan Valley, Philippines where soil-transmitted helminthiasis (STH) is endemic, to analyze the strengths, weaknesses, opportunities, and threats for three intervention components for STH control: mass drug administration (MDA), health education, and sanitation. School teachers and staff generally perceived MDA to be a well-delivered program, but opportunities exist to strengthen other control strategies: health education and school rules on hygiene and sanitation at school. Complete and consistent monitoring of program impact and the availability of up-to-date reports on prevalence of the infection can guide teachers' efforts to promote interventions for STH elimination.

Small bowel obstruction complicating an Ascaris lumbricoides infestation in a 4-year-old male: a case report

BackgroundAscariasis is the leading helminthic infection worldwide, with its peak prevalence noted in children aged 2–10 years. Although mainly asymptomatic, chronic and heavy infestation could lead to severe complications such as malnutrition, poor physical and cognitive development, as well as intestinal obstruction. We report the case of a 4-year-old boy with intestinal obstruction due to Ascaris lumbricoides infestation and discuss its public health significance.Case presentationA 4-year-old Black African boy from the Menchum Division in the Northwest Region of Cameroon, with no history of deworming since birth, presented with a 3-day history of generalized abdominal pains, vomiting and obstipation, and abdominal distention evolving over a period of 6 months. Clinical and paraclinical findings were in favor of a subacute intestinal occlusion associated with an electrolyte imbalance. An exploratory laparotomy was done after correction of the electrolyte imbalance. Perioperative findings revealed a dilated small bowel obstructed by bundles of live worms. An enterotomy of 2 cm in length was done, and the bundles of Ascaris lumbricoides worms extracted manually and by milking through the stoma. His postoperative period was unremarkable, and he was discharged on postoperative day 7. He and his entire household were dewormed with a single dose of mebendazole 500 mg administered orally. A follow-up visit 1 week after discharge revealed a healed abdominal wound and normal bowel functions.ConclusionDespite considerable progress made on the control of soil-transmitted helminthiasis in Cameroon, the program faces a number of bottlenecks. Funding is inadequate, making data acquisition and hence remapping of high-risk zones difficult. Accessibility to enclaved zones where most high-risk children live is difficult, while community sensitization on soil-transmitted helminthiasis and proper education on the right environmental hygienic practices are lacking. All these challenges once addressed could go a long way to help achieve recently set sustainable development goals.

Social media and control of soil-transmitted helminthiasis in Bhutan.

Social media and control of soil-transmitted helminthiasis in Bhutan.

Epidemiological Findings and Policy Implications from the Nationwide Schistosomiasis and Intestinal Helminthiasis Survey in Sudan

Background: The World Health Assembly endorsed the WHO Neglected Tropical Disease (NTD) Roadmap in 2013, in which NTDs were suggested as tracers of equity in the assessment of progress towards the Sustainable Development Goals. Nationwide surveys were undertaken in all 18 states of Sudan to identify the geographical distribution and estimate the prevalence and intensity of schistosomiasis and other helminthiases from December 2016 to March 2017. Improved water and sanitation coverage at the household and school levels and the proportion of respondents who engaged in risk behaviours were assessed. Methods: Using two-stage random sampling, each locality was subdivided into one to three different ecological zones (EZs) based on proximity to water bodies. Probability-proportional-to-size sampling was used to select schools from each EZ. We estimated schistosomiasis and intestinal helminthiasis prevalence in 105,167 school children by urine concentration microscopy and Kato-Katz smears. Risk factors and the impact thereof were investigated using multi-level mixed-effect models. Findings: The overall egg-positive rates were: Schistosoma haematobium, 5·2%; S. mansoni, 0·06%; and intestinal helminths, 5·47%. Severe endemic areas were concentrated in East and South Darfur States (S. haematobium prevalence, 25·23% and 13·91%, respectively). Households and schools with latrines, and especially improved latrines (ventilated improved pit latrines or flush toilets) were associated with lower odds of schistosomiasis infection. Open defecation was strongly associated with schistosomiasis (aOR: 1·50, 95% CI: 1·35-1·66). EZ-level mass drug administration was estimated to be more cost-effective than district-level administration under all circumstances. Interpretation: Endemic schistosomiasis is concentrated in fragile border states. This study provides insight into possible programmes to effectively reduce infections by presenting possible diverse, innovative strategies to disrupt the transmission cycle. Funding Statement: This project was supported by the Korea International Cooperation Agency (KOICA) under the Integrated schistosomiasis and soil-transmitted helminthiasis control program, Sudan. Declaration of Interests: We declare no competing interests. Ethics Approval Statement: This study protocol was reviewed and approved by the institutional review board of the Federal Ministry of Health, Sudan (FMOH/DGP/RD/TC/2016) and the Korea Association of Health Promotion (130750-20,164-HR-020).