Soil-transmitted Helminth Species Research Articles

Gut-microbiome profiles among Soil-transmitted helminths (STHs) infected Ethiopian children enrolled in the school-based mass deworming program.

Soil-transmitted helminths (STHs) and mutualistic gut microbes coexist in the gastrointestinal tract. However, limited data exist regarding how STH infections are associated with gut microbiome profiles. We conducted a cross-sectional analysis of baseline data collected in a longitudinal study to identify and explain differences in microbial communities between STH-infected and non-infected Ethiopian school children. We collected 138 stool samples and analyzed them for STH infection using standard direct wet mount and Kato Katz methods. The gut microbiome profiles were characterized using targeted amplicon sequencing of the 16S rRNA gene from the total DNA extracted from the stools. Children infected with Trichuris trichiura showed significantly lower microbial diversity than those who were non-infected (p<0.05). We also observed significant difference in microbiome composition based on Trichuris trichiura infection status (PERMANOVA p< 0.01). A comparison of microbial taxa at the genus level among participants infected with different helminth species showed a significant increase in Agathobacter relative abundance among children infected with Trichuris trichiura compared to non-infected subjects (adjusted p = 0.001). Our results indicate that changes in the gut microbiome composition may vary depending on the species of helminth present. Further studies should investigate how Trichuris trichiura selectively alters microbiome composition compared to other STH species.

Modeling transmission mechanism to infer treatment efficacy of different drugs and combination therapy against Trichuris trichiura

Trichuris trichiura is one of four soil-transmitted helminth species that, collectively, are responsible for a considerable public health burden. The World Health Organization recommends preventive chemotherapy as the main intervention to eliminate soil-transmitted helminthiasis as a public health problem. Clinical trials estimated the efficacy of different drugs and treatment regimen against T. trichiura and other soil-transmitted helminth species, whilst meta-analyses and modeling efforts were conducted to determine the most efficacious drugs and drug combinations. Of note, the diagnostic error was often neglected, and hence, cure rates (CRs) might be overestimated. We developed a Bayesian model, which estimates drug efficacy against T. trichiura, taking into account the transmission mechanism and the diagnostic error. The model was fitted to individual-level egg count data from an ensemble of seven trials with 29 treatments. We estimated the ‘true’ CRs, which were consistently lower than those reported in the literature. In our analysis, the treatment with the highest CR was combination therapy of albendazole plus pyrantel pamoate plus oxantel pamoate with a CR of 79% and an egg reduction rate (ERR) of 91%. Albendazole plus oxantel pamoate showed the highest ERR of 97% and a CR of 69%. Additionally, we estimated the intensity-dependent sensitivity of the Kato-Katz technique. For 24 eggs per gram of stool, the sensitivity was around 50% for a single Kato-Katz thick smear and increased to almost 70% for duplicate Kato-Katz thick smears. Combination therapies against soil-transmitted helminthiasis should be considered and the evaluation of infection intensity in low transmission settings via multiple Kato-Katz thick smears is recommended.

Persistent transmission of soil-transmitted helminths despite 16 years of uninterrupted Mebendazole- and ivermectin-based preventive chemotherapy in the Lomie Health District (East Region, Cameroon): The emergency of complementary control strategies.

The control of the Soil-Transmitted Helminths (STH) infections primarily relies on the school-based Preventive Chemotherapy (PCT) with mebendazole. Given the efficacy of ivermectin on STH, the control of the latter is expected to be potentialized in areas where ivermectin is also distributed for onchocerciasis and/or lymphatic filariasis control/elimination. This study aimed to assess the prevalence and intensity of STH in the Lomie Health District where annual school-based deworming campaigns and community-directed treatments with Ivermectin have been underway for almost two decades. A quantitative cross-sectional study was conducted in 10 schools of the Lomie Health District, East Region, Cameroon. Stool samples were collected from school-aged children and analysed using the Kato-Katz technique. Semi-structured questionnaires were administered to enrolees to assess compliance with water, sanitation, and hygiene (WASH). Of the 491 children (median age: 9 years; IQR: 7-10) enrolled, 83.9% (95% CI: 80.3-87.1) were infected with at least one STH species. Trichuris trichiura was the predominant species (78.5%), and no hookworm was found. The prevalence trend slightly decreased between 1987 and 2010 (~8%) and remained unchanged since 2010 (p-value = 0.05). Overall, 46.8% and 41.8% of children were heavy-to-moderately infected with Ascaris lumbricoides and T. trichiura. Poor hand hygiene (OR: 2.24, 95% IC: 1.4-3.4, p-value = 0.0002) and the use of river as a source of drinking water (OR: 14.8, 95% IC: 6.9-33.3, p-value = 0.0001) were the main risk factors associated with the STH infection in Lomie Health District. The persistent high prevalence and intensity of STH infection despite 16 years of mebendazole-based PCT and expected collateral impact of ivermectin mass distribution, points to plausible implementation gaps, poor compliance to WASH or sub-optimal efficacy of the anthelminthics used. This study highlights the need to further assess the cause of the persistent high prevalence and implement context-adapted control measures in order to curb STH transmission.

Correlating Cases of Soil-Transmitted Helminths and Remote Sensing Covariates: A Case Study Utilizing 2015, 2017, and 2019 Metadata of Camarines Sur, Philippines.

Soil-transmitted helminth (STH) is a group of helminths that are considered to be neglected tropical diseases (NTDs) and, globally, affect more than 1.5 to 2.6 million people yearly. Depending on the species, they can be acquired by ingesting embryonated eggs from contaminated matter or by skin penetration. Most species of STH are found in the tropics, such as the Philippines. Despite the Mass Drug Administration (MDA), the cases of STH infection continue to rise in the country. Surveys from the Research Institute of Tropical Medicine (RITM) indicate that a high prevalence of STH (Ascaris lumbricoides, Trichuris trichiura, and Necator americanus) was primarily observed in the provinces of the country, such as in Camarines Sur. To correlate remote sensing covariates such as Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built-up Index (NDBI) - to STH-infected cases of the 37 municipalities of Camarines Sur. The available public health record of STH cases from 2015 to 2019 were calculated using the Quantum Geographic Information System (QGIS)and correlated using Pearson Correlation Coefficient. The results showed that infection was higher in children than adults, and A. lumbricoides caused 60% of infection. No correlation of indices with infection cases during 2015 and 2017 was observed; however, 2019 showed a moderate strength (p = 0.037) in correlation. This indicates that infection relied not mainly on vegetation and urbanization but on additional environmental factors and non-environmental variables.

Soil-transmitted helminth (STH) infections in the Wolaita zone in Southern Ethiopia: mid-stage evaluation of the Geshiyaro project and progress towards the interruption of transmission

BackgroundThis paper documents changes in the prevalence and intensity of soil-transmitted helminth (STH) infections in the Geshiyaro project in the Wolaita zone of Southern Ethiopia.MethodsThe Geshiyaro project comprises three intervention arms. Arm 1 is subdivided into the Arm 1 pilot (one district) and Arm 1 (four other districts), both receiving integrated community-wide mass drug administration MDA (cMDA) with intensive water, sanitation, and hygiene (WaSH) interventions. Arm 2 involves 18 districts with cMDA interventions plus the existing government-led One WaSH program, while Arm 3 serves as a control with school-based MDA (sMDA) interventions plus the existing government-led One WaSH program in three districts. The study is designed as a cohort investigation over time, with the establishment of longitudinal sentinel sites where infection levels are assessed annually. A total of 45 longitudinal parasitological surveillance sentinel sites are being used across all three intervention arms to monitor STH prevalence and intensity of infection. From each of the 45 sentinel sites, 150 individuals were randomly selected, stratified by age and gender. The t-test and analysis of variance (ANOVA) were employed to compare infection prevalence and intensity across the three study arms over time.ResultsThe prevalence of STH decreased significantly from 34.5% (30.6%, 38.5%) in 2019 to 10.6% (8.3%, 13.4%) in 2022/2023 (df = 1, P < 0.0001) in the Arm 1 pilot, from 27.4% (25.2%, 29.7%) in 2020 to 5.5% (4.4%, 6.7%) in 2023 (df = 1, P < 0.0001) in Arm 1, from 23% (21.3%, 24.8%) in 2020 to 4.5% (3.7%, 5.3%) in 2023 (df = 1, P < 0.001) in Arm 2, and from 49.6% (47.4%, 51.7%) in 2021 to 26.1% in 2023 (df = 1, P < 0.0001) in Arm 3. The relative reduction in the prevalence of any STH was the highest in the arms employing cMDA, namely Arm 2, with a decrease of 82.5% (79.3%, 84.2%), followed by Arm 1 with a reduction of 80.1% (75.3%, 84.6%), and then the Arm 1 pilot with a decrease of 69.4% (60.1%. 76.6%). Arm 3 employing sMDA had the lowest decrease, with a reduction of 46.9% (43.6%, 51%). The mean intensity of infection (based on Kato–Katz egg count measures) for Ascaris lumbricoides species, which was the dominant STH species present in the study area, decreased significantly in Arms 1 and 2, but only slightly in Arm 3. The prevalence of hookworm and Trichuris trichiura infections were found to be very low in all arms but also decreased significantly.ConclusionsThe reduction in the prevalence and intensity of STH in Arms 1 and 2 revealed steady progress towards transmission interruption based on cMDA intervention, but additional efforts with MDA coverage and WaSH interventions are needed to achieve a prevalence threshold < 2% based on the quantitative polymerase chain reaction (qPCR) diagnostic method.Graphical

Erythrocyte and iron profiles in soil-transmitted helminth-infected children in a rural area in Banten, Indonesia

BACKGROUND Soil-transmitted helminth (STH) infection, frequently caused by Ascaris lumbricoides, Trichuris trichiura, and hookworms (Ancylostoma duodenale and Necator americanus), often gives rise to malabsorption of nutrients that form hemoglobin (Hb) thereby causing anemia. This study aimed to know the difference in erythrocyte profile in children with and without STH infections. METHODS This cross-sectional study involved 205 children from two Panimbang Jaya elementary schools in Pandeglang, Banten, Indonesia. Blood and stool samples were collected from a previous study conducted from November 2021 to May 2022. Erythrocyte parameters were Hb concentration, erythrocyte count, mean corpuscular volume (MCV), mean corpuscular Hb (MCH), and red cell distribution width (RDW). The iron profile included serum iron, total iron-biding capacity (TIBC), and ferritin. Worm infestation was detected by direct stool microscopical examination. Statistical analysis was performed using SPSS software version 20. RESULTS The prevalence of STH infection in Pandeglang was 44.4%, primarily characterized by mild intensity STH infection (79%). The identified STH species were A. lumbricoides, T. trichiura, and combination of both. The median differences between erythrocyte count, MCV, and MCH, and the mean differences of TIBC and serum iron were not statistically significant (p = 0.388, 0.098, and 0.057, and p = 0.304 and 0.455). However, children with STH infection had lower Hb (12.57 versus 12.95 g/dl) and ferritin (19.60 versus 30.57 µg/dl) levels but higher RDW (13.20 versus 13.10%). CONCLUSIONS A high prevalence of STH infection was identified among schoolchildren, but their erythrocyte profiles were similar regardless of STH infection status.

Prevalence and correlates of soil-transmitted helminths in schoolchildren aged 5 to 18 years in low- and middle-income countries: a systematic review and meta-analysis.

According to the Global Burden of Disease (GBD) 2019 report, up to 1.5 million disability-adjusted life years (DALYs) are lost due to soil-transmitted helminths (STHs), and 5.9 million people are at risk of acquiring STHs. Regions with the highest prevalence of STH infections include Sub-Saharan Africa, China, South America, and Asia. While there are numerous fragmented studies on STH, comprehensive information on the prevalence and geographic distribution of different species, as well as their regional variations in the context of STHs is limited. The present systematic review and meta-analysis study attempts to provide a summary of the prevalence, geographical variation, and determinants of STHs among schoolchildren aged 5 to 18 years. An extensive literature search was carried out using PubMed, Embase, Cinhal, and Psychinfo for studies published between 1999 and 2022 that reported the rate of STH infection in school-going children aged 5-18 years. A random effects model was employed in this meta-analysis due to expected heterogeneity. Subgroup analysis was carried out based on sex and STH species because of expected geographical variation. A total of 19,725 of the 49,630 children examined were infected with STH, yielding an overall pooled prevalence of 37.16% (95% CI: 29.74-44.89). The prevalence was highest in the Western Pacific region at 50.41% (95% CI: 33.74-67.04) followed by Europe at 39.74% (95% CI: 20.40-61.0) and Africa at 37.10% (95% CI: 26.84-47.95). Ascaris lumbricoides was found to be the most prevalent helminth with a prevalence of 24.07% (95% CI: 17.07-31.83). The Western Pacific region is classified as a High-risk Zone (HRZ), while Southeast Asia, Africa, Europe, and the Eastern Mediterranean are classified as moderate-risk zones (MRZs). We found a 12% reduction in the pooled prevalence of STH infection from 1999 to 2012. Ascaris lumbricoides was the predominant species among schoolchildren. Mass Drug Administration (MDA) of Albendazole tablets and improved water, sanitation, and hygiene (WASH) practices are effective in controlling and preventing STH. Ensuring their implementation and access is crucial to addressing the problem. https://www.crd.york.ac.uk/prospero/#loginpage, CRD42022333341.

Exploring factors associated with Trichuris trichiura infection in school children in a high-transmission setting in Kenya

ObjectivesKenya has implemented a national school-based deworming program, which has led to substantial decline in the prevalence of soil-transmitted helminths (STHs), although some pockets of infections remain. To effectively design an STH control program that leads to significant reductions of Trichuris trichiura, there is a need to understand the drivers of persistent infection despite ongoing treatment programs. MethodsThis study was conducted between July and September 2019 at the south coast of Kenya, using a two-stage sampling design. First, a school-based cross-sectional survey was conducted in 2265 randomly selected school children from selected schools in areas known to be endemic for T. trichiura. After this, we conducted a nested case-control study wherein all children positive for T. trichiura (142) were matched to 148 negative controls based on age and village. A household survey was then conducted with all household members of cases and controls. In addition, a subsample of 116 children found to be infected with T. trichiura were followed up to assess the efficacy of albendazole at day 21 post-treatment. The predictors of presence of T. trichiura were investigated through multilevel logistic regression, considering clustering of infection. ResultsOverall, 34.4% of the children were infected with at least one STH species; T. trichiura was the most common (28.3%), 89.1% of those with T. trichiura had light-intensity infections. The prevalence of T. trichiura was significantly higher in male children and was positively associated with younger age and number of people infected with T. trichiura in a household. The parasitological cure rate and egg reduction rate of T. trichiura were 35% and 51%, respectively. Other STHs identified were hookworm (9.6%) and Ascaris lumbricoides (5.7%). ConclusionsT. trichiura remains a significant public health challenge in the study area with albendazole treatment efficacy against the parasite, remaining lower than the World Health Organization–recommended thresholds. Because of the observed focal transmission of T. trichiura in the current area, control efforts tailored to local conditions and targeting lower implementation units should be used to achieve optimal results on transmission.

Occurrence of Soil-Transmitted Helminths in Selected Waste Dumpsites in OtuokeCommunity, Ogbia Local Government Area, Bayelsa State, Nigeria

Background: Soil-transmitted helminths (STH) are global health concerns, particularly in tropical and subtropical regions with poor sanitation. Waste dumpsites contribute to STH transmission, polluting soil, groundwater, and air quality in any location where they are situated. This study was carried out to investigate the occurrence of soil-transmitted helminths in selected waste dumpsites in the Otuoke community, Ogbia Local Government Area, Bayelsa State. Methods: 46 soil samples were randomly collected from different dumpsites and analyzed using Zinc sulphate floatation, Baermann technique and concentration method. Eggs and larvae of parasites present were identified morphologically by microscopic examination under x4 and x 10 objective lenses using identification keys. The Statistical Package for Social Science (SPSS) version 22 was used to analyze the data at 0.05 significant levels. Results: The overall rate of contamination was 28.3%. Eggs and larvae of three soil-transmitted helminths were recovered from the soil samples. The species of soil-transmitted helminths encountered in the study were Ascaris spp. 4(8.6%), Hookworm specie 5(10.9%) and Strongyloides spp. 15(32.6%). The most prevalent soil-transmitted helminth recorded in this study was the larvae of Strongyloides spp. Nevertheless, variations in the distribution of soil-transmitted helminths across locations varied significantly (P = 0.035; P&lt;0.05). Conclusion: The findings suggest a need for a strategic intervention to improve sanitary status precisely in the locations where parasitic contaminations were present, whereas continuous monitoring and preventive measures should be implemented in the locations with no parasitic contamination to prevent the emergence of soil-transmitted helminths infection.

A One Health approach toward the control and elimination of soil-transmitted helminthic infections in endemic areas

Soil-transmitted helminths (STHs) pose significant health challenges, particularly in developing countries. Over 2 billion people are estimated to have been infected with at least one STH species. These parasites rely on the soil for part of their life cycle and are transmitted to humans through ova ingestion or skin penetration. Key risk factors include poor water, sanitation, hygiene practices, limited healthcare access, and poverty. Globally, STHs are primarily controlled through chemo-preventive deworming of high-risk groups in moderate (where prevalence of STHs is between 20 % and 50 %) to highly endemic areas (prevalence >50 %). Despite the use of deworming to control the STHs in endemic areas, infections still occur. The aim of this article is to explore the potential for enhancing STH control and elimination as Neglected Tropical Diseases (NTDs) in endemic areas through an integrated approach—the One Health approach. The current control program has a single strategy of chemoprophylaxis; in the integrated approach to control of STHs, the parasite control strategies besides being based on the epidemiology of the parasite (endemicity), also include strategies based on the biology (transmission cycle) of the parasites and human behavior patterns in endemic areas. Through the involvement of local communities, healthcare authorities, and stakeholders, participatory approaches foster collaborative efforts to devise and implement control measures. By integrating this integrated approach into existing healthcare and educational initiatives, more effective results can be achieved. The promotion of health education, clean water access, improved sanitation, and hygiene awareness can further enhance control strategies and reduce STH prevalence sustainably. Here, we highlight the benefits of adopting an integrated (One Health) approach to tackle STHs in endemic areas. Through community empowerment and multi-sectorial collaboration, we can strengthen our collective efforts to combat STHs and alleviate the burden of these NTDs.

Prevalence of Soil-Transmitted Helminth Infections in Malaysia: A Systematic Review and Meta-Analysis

BACKGROUND: Prevention and control of soil-transmitted helminth (STH) infections in Malaysia remain a challenge, especially among aborigine and rural population. Despite several community-based reports, there are lacking national data on the overall prevalence for STH infection. AIM: The study aimed to determine the prevalence, endemic species, and distribution and risk zones (RZs) for STH infections in Malaysia through a systematic review and meta-analysis of the data published between 1999 and 2019. METHODS: This study employed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The databases used in this review include SCOPUS, WEB OF SCIENCE, OVID MEDLINE, and PUBMED. The random-effects model determined the pooled prevalence estimate (PPE) while Cochran’s Q-test evaluated the heterogeneity. RESULTS: A total of 13240 samples were examined during the period under review with 6235 were infected with one or more species of STHs. The overall PPE for STH infections was 51% (95% Confidence interval [CI]: 34, 67). PPEs for sub-groups ranged between 13% (95% CI: 5, 22) and 69% (95% CI: 50, 87). Highest PPEs for STH infections were observed among aborigine children (69% 95% CI: 50, 87). Trichuris trichiura was the most prevalent species (46%, 95% CI: 27, 65). Over 46% (17/37) of the studies, especially among aborigine community and their area showed high-HRZ for STH infections. CONCLUSION: STH infections involving T. trichiura, Ascaris lumbricoides, hookworms and Strongyloides stercoralis are highly prevalent among aborigine community. Primary and secondary prevention such as the use of anthelmintic, health education, and adequate sanitation was essential in the control of these infections in Malaysia to improve individual and community health.

Soil-Transmitted Helminths in Kindergarten Children: Prevalence, Intensity and Associated Factors in Bule Hora Town.

Background: Soil-transmitted helminth (STH) infections are a common problem in Ethiopia. This parasite affects the physical and mental development of children, causing malnutrition and iron deficiency anaemia. However, there are inadequate studies that demonstrate the extent of STHs and associated factors among kindergarten children in South Ethiopia, particularly in the study area. Objective: The aim of this study is to determine the prevalence, intensity, and associated factors of STH infection among kindergarten students in Bule Hora town. Methods: An institution-based cross-sectional study was conducted among randomly selected 235 kindergarten children in Bule Hora town from January to February 2023. A pretested questionnaire was used to collect information on associated factors. EpiData and SPSS were used for data entry and analysis, respectively. Binary logistic regression analyses were performed to identify risk factors. Results: In the present study, the prevalence of STH was 28.5% (95% CI: 22.7%-34.3%). A. lumbricoides 26 (11.1%) was the most common parasite identified. The arithmetic mean (+SD) of the egg counts for each species of STHs was as follows: A. Lumbricoides 1886.9 (+2103.2), T. Trichiura 299.2 (+305.8), and hookworms 756.1 (+739.4). Factors that showed significant association in the current study were hand washing after the toilet (AOR: 2.992, 95% CI: 1.299-6.891,), fingernail trimming (AOR: 3.646, 95% CI: 1.704-7.798,), and shoe wearing habit (AOR: 2.143, 95% CI: 1.170-3.924,). Conclusion: STH infection is a health problem among kindergarten children in Bule Hora town. Comprehensive health education on the value of hygienic habits, improved sanitation, and routine deworming of kindergarten children should be included in prevention and control efforts.

Prevalence and Determinants of Geohelminthiasis among School-Age Children in Jimma City, Ethiopia.

School-age children (SAC) are at a higher risk of geohelminth or soil-transmitted helminth (STH) infections due to their practice of walking and playing barefoot, lack of adequate sanitary facilities, and poor personal hygiene. In Ethiopia, periodic deworming has been implemented since 2013 with the aim of interrupting the transmission of STH in children by 2025. To evaluate the likely success of such a control program, it is crucial to monitor the transmission of STH, especially in peri-urban settings where environmental sanitation is modest. The aim of this study was to determine the prevalence and determinants of STH infections among SAC in peri-urban areas of Jimma City, Southwestern Ethiopia. A community-based cross-sectional study was conducted in five peri-urban Kebeles of Jimma City from July to September, 2021. Systematic random sampling was used to select 522 households with at least one child, and 478 children (5-15 years old) were recruited randomly from the households. Data on sociodemographic and potential risk factors were collected using a structured questionnaire. Stool samples from each study participant were collected and examined microscopically using the Kato-Katz technique. Multivariate logistic regression model was used to identify risk factors associated with STH infections. The prevalence of any STH among SAC was 23.4%, with Ascaris lumbricoides being the predominant STH species (15.7%), followed by Trichuris trichiura (9%) and hookworm (2.1%). Most (86.6%) of the STH-positive SAC had a single infection and a light infection intensity (88.2%), with a mean intensity of 367.4 eggs per gram. Location of Kebele (AOR = 2.73; 95% CI: 1.21-6.16, p=0.016), lack of hand washing after defecation (AOR = 6.39; 95% CI: 3.16-12.95, p < 0.001), untrimmed fingernails (AOR = 2.65; 95% CI: 1.56-4.51, p < 0.001), and lack of previous deworming (AOR = 2.90; 95% CI: 1.47-5.74, p=0.002) were significant predictors for STH infections among SAC. In conclusion, the study revealed that STH infections are significant health problem in the peri-urban areas of Jimma City. Strengthening periodic deworming and improving children's hygiene through health education are required to reduce the transmission.

Distribution and treatment needs of soil-transmitted helminthiasis in Bangladesh: A Bayesian geostatistical analysis of 2017-2020 national survey data.

In Bangladesh, preventive chemotherapy targeting soil-transmitted helminth (STH) infections in school-age children has been implemented since 2008. To evaluate the success of this strategy, surveys were conducted between 2017 and 2020 in 10 out of 64 districts. We estimate the geographic distribution of STH infections by species at high spatial resolution, identify risk factors, and estimate treatment needs at different population subgroups. Bayesian geostatistical models were fitted to prevalence data of each STH species. Climatic, environmental, and socioeconomic predictors were extracted from satellite images, open-access, model-based databases, and demographic household surveys, and used to predict the prevalence of infection over a gridded surface at 1 x 1 km spatial resolution across the country, via Bayesian kriging. These estimates were combined with gridded population data to estimate the number of required treatments for different risk groups. The population-adjusted prevalence of Ascaris lumbricoides, Trichuris trichiura, and hookworm across all ages is estimated at 9.9% (95% Bayesian credible interval: 8.0-13.0%), 4.3% (3.0-7.3%), and 0.6% (0.4-0.9%), respectively. There were 24 out of 64 districts with an estimated population-adjusted STH infection prevalence above 20%. The proportion of households with improved sanitation showed a statistically important, protective association for both, A. lumbricoides and T. trichiura prevalence. Precipitation in the driest month of the year was negatively associated with A. lumbricoides prevalence. High organic carbon concentration in the soil's fine earth fraction was related to a high hookworm prevalence. Furthermore, we estimated that 30.5 (27.2; 36.0) million dosages of anthelmintic treatments for school-age children were required per year in Bangladesh. For each of the STH species, the prevalence was reduced by at least 80% since treatment was scaled up more than a decade ago. The current number of deworming dosages could be reduced by up to 61% if the treatment strategy was adapted to the local prevalence.

Effectiveness of one and two doses of ivermectin mass drug administration in reducing the prevalence and intensity of soil-transmitted helminth (STH) infections in Western Province, Solomon Islands: a cluster-randomised, before-after analysis

Ivermectin mass drug administration (MDA) is effective for controlling onchocerciasis and scabies, with evidence supporting its role in some species of soil-transmitted helminth (STH) infections. In the context of RISE, a cluster-randomised trial for scabies, this study evaluated the effectiveness of ivermectin MDA in reducing STH burden in the Western Province of Solomon Islands. Twenty villages were randomised 1:1 to receive ivermectin MDA as one dose (IVM-1) or two doses (IVM-2) for scabies. The effectiveness of one and two doses in reducing STH prevalence and intensity was evaluated before (May 2019) and 21 months after (February 2021) MDA in May 2019. All residents aged 12 months or older in the study villages were eligible to participate and provide stool specimens. Species-specific STH infection and intensity were assessed using quantitative PCR. We compared prevalence and intensity of infection between baseline and 21 months in each intervention arm individually using cluster-level analysis (adjusted for clustering) and individual-level analysis (adjusted for sex, age, and clustering). The primary outcomes were the prevalence risk difference (RD) from the cluster-level analysis, and the change in adjusted odds of infection from the individual-level analysis. Secondary outcomes included change in incident rates of mean eggs per gram (epg) of stool from baseline to 21 months, relative risk difference in prevalence and relative change in odds of infection between arms at 21 months. Sex data (male/female) were self-reported. Overall, STH infection was assessed in 830 participants from 18 villages at baseline and 1172 from 20 villages at follow-up. Females represented 58% (n=478) of the sample at baseline and 59% (n=690) at follow-up. We observed a reduction in Strongyloides spp. prevalence following two doses of ivermectin MDA in the cluster-level analysis from 7.0% (32/458 participants) to 1.2% (8/674 participants), corresponding to a RD of-0.07 (95% CI-0.14 to-0.01, p=0.036), and in the individual-level analysis (OR 0.11, 95% CI 0.04-0.33, p<0.001). T.trichiura prevalence decreased following one dose from 19.4% (74/372 participants) to 11.7% (56/505 participants) (OR 0.44, 95% CI 0.26-0.73, p=0.0040), while egg count reduced in both arms (IVM-1: IRR 0.28, 95% CI 0.11-0.70, p=0.0070; IVM-2: IRR 0.18, 95% CI 0.08-0.40, p<0.001), in the individual-level analysis. We did not detect a significant difference in effect measures between the one- and two-dose arms for any species after 21 months. Our study highlights the long-term benefits of ivermectin MDA in reducing the burden of Strongyloides spp. and T.trichiura. STH control programs should leverage the geographical overlap of NTDs, existing drug distribution channels, and broad-spectrum agents. The National Health and Medical Research Council of Australia.

Baseline soil-transmitted helminth and schistosome infection in the Geshiyaro project, Ethiopia: A unique transmission interruption project using biometric fingerprinting for longitudinal individual analysis.

The Geshiyaro project aims to assess the feasibility of interrupting transmission of soil-transmitted helminths (STH) and schistosome (SCH) infection in the Wolaita zone of southern Ethiopia through high coverage community-wide mass drug administration (MDA), in combination with improved water, sanitation, and hygiene services and behaviour change communication delivered through the existing health care infrastructure. To accurately measure treatment coverage a population census was conducted enrolling individuals with biometric fingerprinting and barcoded ID cards. This paper details the baseline census and parasitology surveys conducted before the start of any interventions. The census was conducted in five of the 15 Wolaita districts between October 2018 and December 2019, enrolling all consenting participants from every household. Simultaneously, a cross-sectional parasitology survey was conducted in 130 out of 361 randomly selected communities from all 15 districts, with 100 individuals across all age groups (infant to adult) per community providing stool and urine for analysis by duplicate Kato-Katz and a point-of-care circulating cathodic antigen (POC-CCA) to test for Schistosoma mansoni and STH, and microhaematuria and urine filtration for Schistosoma haematobium. Of the 130 communities, 30 were randomly selected for annual, longitudinal parasitological monitoring, with 150 randomly selected individuals from infant to adult providing two days of stool and urine samples for analysis by the same diagnostic tests per community. In total 97,919 households participated in the baseline census enrolling 466,071 individuals, with parasitological data obtained from 10,785 people. At baseline, 15.5% were infected with at least one STH species, with Ascaris lumbricoides (9.5%), followed by hookworm (7.2%) and Trichuris trichiura (1.8%). Substantial heterogeneity in STH prevalence was observed between communities ranging from 0% to 61% where most infections were low intensity. Schistosoma mansoni infection was the dominant schistosome infection (0.85% by Kato-Katz and 13.3% by POC-CCA trace negative and 21.5% trace positive), with few Schistosoma haematobium infections identified (2.77% haematuria positive and 0.13% positive by urine filtration). While the national control program in Ethiopia has made good progress in reducing prevalence of STH and SCH in Wolaita since it was launched in 2015, there remain areas of persistent infection suggesting the existence of environmental or behavioural risk factors that contribute to ongoing transmission. This project aims to identify the most efficient intervention strategies to reduce community burden and reach interruption of transmission.

Associations between soil-transmitted helminth infections and physical activity, physical fitness, and cardiovascular disease risk in primary schoolchildren from Gqeberha, South Africa.

School-aged children in low- and middle-income countries carry the highest burden of intestinal helminth infections, such as soil-transmitted helminths (STH). STH infections have been associated with negative consequences for child physical and cognitive development and wellbeing. With the epidemiological transition and rise in cardiovascular disease (CVD), studies have shown that helminth infections may influence glucose metabolism by preventing obesity. Thus, the aim of this study was to determine the association of STH infections in schoolchildren from Gqeberha, focusing on physical activity, physical fitness, and clustered CVD risk score. This cross-sectional study involved 680 schoolchildren (356 girls and 324 boys; mean age 8.19 years, SD±1.4) from disadvantaged communities in Gqeberha (formerly, Port Elizabeth), South Africa. Stool samples were collected and examined for STH infections using the Kato-Katz method. Physical activity (accelerometer) and physical fitness (grip strength, 20 m shuttle run) were measured using standard procedures. Furthermore, anthropometry, blood pressure, as well as glycated haemoglobin and lipid profile from capillary blood samples were assessed. We employed one-way ANOVAs to identify the associations of STH infections in terms of species and infection intensity with physical activity, physical fitness, and clustered CVD risk score. We found a low STH infection prevalence (7.2%) in our study, with participants infected with at least one intestinal helminth species. In comparison to their non-infected peers, children infected with STH had lower mean grip strength scores, but higher mean VO2max estimation and higher levels of MVPA (p < .001). When considering type and intensity of infection, a positive association of A. lumbricoides infection and MVPA was found. In contrast, light T. trichiura-infected children had significantly lower grip strength scores compared to non and heavily-infected children. VO2max and MVPA were positively associated with light T. trichiura infection. No significant association between the clustered CVD risk score and infection with any STH species was evident. STH-infected children had lower grip strength scores than their non-infected peers, yet, achieved higher VO2max and MVPA scores. Our study highlights that the type and intensity of STH infection is relevant in understanding the disease burden of STH infections on children's health. The findings of our study must be interpreted cautiously due to the low infection rate, and more research is needed in samples with higher prevalence rates or case-control designs.

Community-wide versus school-based targeted deworming for soil-transmitted helminth control in school-aged children in Vietnam: the CoDe-STH cluster-randomised controlled trial

Soil-transmitted helminth (STH) infection control programs typically consist of school-based preventive chemotherapy (PC) targeted to school-aged children. STH reservoirs in untreated community members contribute to ongoing transmission in children. The CoDe-STH (Community Deworming against STH) trial, conducted in Dak Lak province, Vietnam, between October 2019 and November 2020, aimed to determine whether community-wide mass drug administration (MDA) is more effective than school-based targeted PC in reducing STH prevalence and intensity in children. In this two-arm cluster randomised controlled trial, 64 primary schools were randomly assigned 1:1 to receive either school-based targeted PC ("school arm") or community-wide MDA ("community arm"). A single dose of albendazole 400mg was used for deworming. The primary outcome was hookworm prevalence in schoolchildren, measured using quantitative real-time PCR. We also measured infection intensity for Necator americanus only, using qPCR cycle threshold (Ct) values converted into eggs per gram of faeces (EPG). Analysis was by intention to treat. The trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12619000309189). The analysis included 4955 children in the school arm and 5093 children in the community arm. N.americanus was the dominant STH species. The relative reduction in hookworm prevalence was not significantly different between the school arm (30.1%, 95% confidence interval [CI] 20.5-36.9) and the community arm (34.6%, 95% CI 19.9-49.4). Due to lower baseline prevalence than expected, the study was underpowered to detect a difference in prevalence reduction between the study arms. The community arm showed significantly greater relative reduction in N.americanus infection intensity (56.0%, 95% CI 39.9-72.1) compared to the school arm (3.4%, 95% CI-24.7 to 31.4). The community arm also showed greater relative reduction in prevalence of moderate-to-heavy intensity (≥2000 EPG) N.americanus infections (81.1%; 95% CI 69.7-92.6) compared to the school arm (39.0%, 95% CI 13.7-64.2). Although no impact was seen on overall prevalence, community-wide MDA was more effective in lowering N.americanus infection intensity in schoolchildren compared to school-based targeted PC, measured 12 months after one round of albendazole deworming with high coverage. National Health and Medical Research Council, Australia (APP1139561).

Assessment of the capacity of Whatman filter papers as support to store stools for the molecular diagnostic testing of soil-transmitted helminthiasis

Storage of stools for the detection of soil-transmitted helminths (STH) remains challenging for the molecular diagnostic testing of STH infections. This study aimed to overcome this challenge by assessing the capacity of Whatman filter papers to store stools for the molecular detection of STHs. Stool samples were collected from school-aged children of soil-transmitted helminthiasis endemic areas of Cameroon and then, analysed using Kato Katz technique. For this study, 128 and 40 stool samples respectively with and without STH eggs were analysed. From each sample, 10, 20, 40 and 80 mg of stool were weighted and spread on 6 grades of Whatman filter papers that were stored at room temperature from one to ten weeks. DNA was extracted from spread stool using CTAB based-method. The amount of stool to spread on filter papers and the grade of filter paper offering good storage were determined by amplifying specific DNA fragments of Ascaris lumbricoides. The capacity of filter papers to store stool samples for several weeks before the molecular detection of STH species was assessed by amplifying specific DNA fragments of different STHs. The amplification rates of A. lumbricoides were significantly higher (P < 0.0001) for 10 and 20 mg of stored stools. Stools spread on Whatman paper grade 2 yielded the highest amplification rate of 100% for A. lumbricoides, T. trichiura and hookworm. PCR revealed STH infections in all the 128 spread stools carrying STH eggs. It also revealed Necator americanus and Ancylostoma duodenale respectively in 10 and 13 of 15 spread stools contained hookworm eggs. PCR confirmed the co-infections of these hookworm species as well as that of A. lumbricoides and Trichuris trichiura in 7 spread stools. Out of 40 stools without STH eggs, PCR revealed that 5 (12.5%) and 9 (22.5%) had respectively A. lumbricoides and T. trichiura infections. The amplification rate of each STH species was 100% from one to 8 weeks and decreased to 86.7% after 10 weeks of storage. This study highlighted the capacity of filter papers to store stools for the molecular detection of STHs. Storing stools on these papers will enable to monitor and evaluate control programs and ensure post-elimination surveillance.

Prevalence of soil-transmitted helminths and associated risk factors among primary school children in Kandahar, Afghanistan: A cross-sectional analytical study.

Soil-transmitted helminth (STH) infections are global health problem, especially in low-income countries. Main objectives of this study were to estimate the prevalence and intensity of STH and its risk factors among school children in Kandahar city of Afghanistan. This was a school-based cross-sectional analytical study, with data collected during eight-month-period (May-December, 2022) from 6- and 12-years old school children in Kandahar city, Afghanistan. All the stool samples were examined by saline wet mount method and Kato-Katz technique. Data were analyzed by using descriptive statistics, Chi square test, and multivariate logistic regression. A total of 1275 children from eight schools of Kandahar city were included in this study. Mean age of these children was 8.3 years with 53.3% boys. The overall prevalence of any intestinal parasitic infection was 68.4%. The overall prevalence of STH infection was 39.1%, with Ascaris lumbricoides (29.4%) as the most prevalent STH species. Mean intensity of overall STH infection was 97.8. Multivariate logistic regression revealed playing barefoot (AOR 1.6, 95% CI 1.1-2.2), not washing hands after defecating and before eating (AOR 1.3, 95% CI 1.0-1.7), having untrimmed nails (AOR 1.4, 95% CI 1.1-1.8), and belonging to poor families (AOR 1.3, 95% CI 1.0-1.7) as the risk factors associated with the predisposition of school children for getting STH in Kandahar city of Afghanistan. There is high prevalence of STH among school children of Kandahar city in Afghanistan. Most of the risk factors are related to poverty, decreased sanitation, and improper hygiene. Improvement of socioeconomic status, sanitation, and health education to promote public awareness about health and hygiene together with periodic mass deworming programs are better strategies for the control of STH infections in Afghanistan.