Soil-transmitted Helminth Infections Research Articles

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.

Malaria and soil transmitted helminths among patients attending some hospitals in Kano Metropolis, Kano State, Nigeria

Soil-transmitted helminths (STHs) and Plasmodium falciparum are known to the causative agents of neglected tropical diseases that continue to pose significant public health challenges in Nigeria and other endemic countries. This study was aimed at determining malaria and STHs coinfection in Kano metropolis, Kano state, Nigeria. The prevalence of malaria and STHs was determined using microscopy and formol ether concentration methods, respectively. Data on socio-demographic and risk factors were collected from three hundred (300) patients using structured questionnaires. The findings revealed a high prevalence of malaria (92.7%) and low STHs (19.0%). Malaria was more prevalent in males (52.3%) than females (40.3%), with the highest prevalence observed among individuals aged 6 – 12 years (25.7%). The difference in malaria prevalence based on age was not statistically significant (p&gt;0.05), contrary to gender which showed a significant difference in their association (p&lt;0.05). STHs infections were more common in participants aged between 6 - 12 years (11.3%), and the difference in prevalence among age groups was statistically significant (p&lt;0.05). Among the study sites, patients exhibited a higher prevalence of Ascaris infection (14.3%) compared to Hookworm infection (4.6%). Co-infection was recorded in 19.0% of the patients, while 73.7% had malaria infection alone. During this study, malaria and STHs were prevalent in Kano metropolis and there was a co-infection of Malaria and STHs among patients attending the selected hospitals in Kano.

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.

Myeloid- and epithelial-derived RELMα contribute to tissue repair following lung helminth infection.

Soil-transmitted helminth (STH) infections impact billions of individuals globally; however, there is a need to clarify the long-term impacts of these infections on pulmonary health owing to their transient migration and subsequent damage to the lungs. In mouse models of these infections using Nippostrongylus brasiliensis, lung pathology persists at later time points post single infection. These studies also indicate the persistent transcriptional expression of resistin-like molecule α (RELMα), an immunomodulatory protein induced in type 2 immunity and alternatively activated macrophages. Using constitutive and tamoxifen-inducible cell-specific RELMα knockout mouse strains, we identified that epithelial- and myeloid-derived RELMα protein remained elevated at 30 days post infection and altered the immune cell signature and gene expression in lung compartments. Histopathological assessment of alveolar damage revealed a role for RELMα in tissue repair, suggesting the importance of sustained RELMα expression for lung recovery from helminth infection. Acellular three-dimensional (3D) lung scaffolds were prepared from the lungs of wild-type (WT), RELMα KO-naive, or 30 days post N. brasiliensis-infected mice to assess their ability to support epithelial cell growth. N. brasiliensis infection significantly altered the scaffold and impaired epithelial cell growth and metabolic activity, especially in the RELMα KO scaffolds. These findings underscore a need to identify the long-term impacts of helminth infection on human pulmonary disease, particularly as alveolar destruction can develop into chronic obstructive pulmonary disease (COPD), which remains among the top global causes of death. Translation of these findings to human protein resistin, with sequence homology to RELMα therapeutic opportunities in lung repair.

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).

Enhancing Soil-Transmitted Helminth Detection in Microscopic Images Using the Chain Code for Object Feature Extraction

Soil-Transmitted Helminth (STH) infections are a grave global health issue, which involves particularly in countries that are developing with insufficient sanitation and limited access to healthcare. With better intestinal helminth egg detection technology, health facilities in areas with limited resources can identify and treat these infections more promptly. It is necessary to create a strong framework and an effective method to solve this challenge. The outcomes of this study could assist in parasite infection discovery and public health. Chain code-based feature extraction strategy can also be the foundation for the development of comparable approaches for diagnosing various parasitic diseases. Overall, the neural network design used in this study makes the model that is produced a good model that assigns well to never-before-seen data. The significance of image processing technologies in the medical field is shown by this study.

Case studies of clinical decision-making through prescriptive models based on machine learning

BackgroundThe development of computational methodologies to support clinical decision-making is of vital importance to reduce morbidity and mortality rates. Specifically, prescriptive analytic is a promising area to support decision-making in the monitoring, treatment and prevention of diseases. These aspects remain a challenge for medical professionals and health authorities. Materials and MethodsIn this study, we propose a methodology for the development of prescriptive models to support decision-making in clinical settings. The prescriptive model requires a predictive model to build the prescriptions. The predictive model is developed using fuzzy cognitive maps and the particle swarm optimization algorithm, while the prescriptive model is developed with an extension of fuzzy cognitive maps that combines them with genetic algorithms. We evaluated the proposed approach in three case studies related to monitoring (warfarin dose estimation), treatment (severe dengue) and prevention (geohelminthiasis) of diseases. ResultsThe performance of the developed prescriptive models demonstrated the ability to estimate warfarin doses in coagulated patients, prescribe treatment for severe dengue and generate actions aimed at the prevention of geohelminthiasis. Additionally, the predictive models can predict coagulation indices, severe dengue mortality and soil-transmitted helminth infections. ConclusionsThe developed models performed well to prescribe actions aimed to monitor, treat and prevent diseases. This type of strategy allows supporting decision-making in clinical settings. However, validations in health institutions are required for their implementation.

Representativeness of a mobile phone-based coverage evaluation survey following mass drug administration for soil-transmitted helminths: a comparison of participation between two cross-sectional surveys

ObjectivesWith increasing mobile phone subscriptions, phone-based surveys are gaining popularity with public health programmes. Despite advantages, systematic exclusion of participants may limit representativeness. Similar to control programmes for neglected tropical...

Community and School-Based Surveys of Soil-Transmitted Helminth Infections on Samosir Island, Indonesia

Soil-transmitted helminth (STH) infections are common in tropical and sub-tropical regions where they can have substantial local public health impacts. This study aimed to evaluate the prevalence of STH infection in the community and children aged 6 to 11 years attending government-run schools in the Simanindo sub-district of Samosir Island. In total, 314 individuals in the community and 187 children aged 6 to 11 years attending government schools were invited to provide a fecal sample. All fecal samples were examined microscopically using the Kato-Katz technique. The prevalence of STH infection in the community was 46.8% (147/314). Infections were caused by Ascaris lumbricoides (n=52), followed by Trichuris trichiura (n=48), and hookworms (n=26). The prevalence of STH infection in school-age children was 4.8% in 2023. All infections in this cohort were due to T. trichiura. Even though the MDA program effectively controls A. lumbricoides and hookworm infections in school children, the problem of controlling T. trichiura infection remains. Therefore, selective treatment after fecal sample examination is needed to prevent T. trichiura infection and the potential for infection-associated anemia. Health education focusing on personal hygiene and environmental sanitation is still important for preventing STH infections. The suggestion is a new community-based survey with random sampling is necessary to ensure the present prevalence of STH in the community.

Preschool child growth attainment and velocity during an agriculture intervention in rural Panama may be diminished by soil-transmitted helminths.

Agricultural interventions are often recommended to address undernutrition in subsistence farming communities. However, intensified agriculture exposure can increase soil transmitted helminth (STH) infections, which are linked with poor child growth. This study examined impacts of the VERASAN public health and agricultural intervention program on preschool child growth attainment (HAZ and WAZ) and relative growth velocity over 7 months [change in height-for-age (∆HAD) and weight-for-age (∆WAD) difference]. VERASAN was initiated in 15 subsistence farming communities in rural Panama experiencing chronic undernutrition. Activities targeted improved household food security, preschool child diets and growth by intensifying and diversifying household agriculture. Our objectives were to explore the relationship between VERASAN and preschool child growth attainment (HAZ and WAZ) and velocity (∆HAD and ∆WAD) during one agricultural cycle in 238 households. We compared those new to VERASAN with those involved for 1 or 5 years, and identified if agricultural practices, food security, diet diversity and treatment of pre-existing STH infection were associated with growth attainment or velocity. Prior participation in VERASAN did not directly influence WAZ, HAZ or ΔHAD but VERASAN-related benefits had an indirect influence. ΔHAD was positively associated with VERASAN-associated improvements in diet diversity and food security. HAZ and WAZ during land preparation were positively associated with diet diversity and HAZ with food security during harvest. HAZ was negatively associated with children visiting the agricultural plot, consuming leafy green vegetables and pre-existing hookworm infections. Both agricultural season and STH influenced ΔWAD. Children in VERASAN for 1 or 5 years experienced growth faltering between land preparation and growing season, but not those new to VERASAN. In contrast, between growing and harvest, ∆WAD declined in children new to VERASAN compared to children in VERASAN for longer. ΔWAD from land preparation to harvest was higher with pre-existing Ascaris infection whereas it was lower between growing season and harvest for pre-existing hookworm infection. In a context of preschool child growth faltering, malnutrition and STH infections, improved food security, agricultural production and diet diversity associated with VERASAN were associated with improved growth. In contrast, STH infections were negatively associated with some, but not all, growth outcomes.

Prevalence and intensity of soil-transmitted helminth infections in Uganda: Results from population-based prevalence surveys in five districts.

Soil-transmitted helminth (STH) infections are caused by roundworms (Ascaris lumbricoides), whipworms (Trichuris trichiura), and hookworms (Necator americanus and Ancylostoma duodenale). In Uganda, baseline surveys conducted during the late 1990s and early 2000s suggested STH infections were common, with prevalence >50% among surveyed schoolchildren. In 2003, a national program was launched with mass preventative chemotherapy (PC) and health education for children 1-14 years old. Little evidence is available to show the impact of national deworming. We conducted population-based, cross-sectional household surveys in five districts (Buikwe, Kassanda, Kiryandongo, Kisoro, and Rubanda) in March and May 2022. Our primary objective was to estimate STH prevalence by species due to infections of any intensity and infections of moderate-to-heavy intensity among preschool-aged children (PSAC, 1-4 years old), school-aged children (SAC, 5-14 years old), and women of reproductive age (WRA, 15-49 years old). Laboratory technicians used duplicate Kato-Katz microscopy to determine fecal egg count. Overall, 3,352 PSAC; 3,884 SAC; and 1,226 WRA provided stool samples. The prevalence of any infection remained high in Kisoro at or above ~50% within all risk groups. In other districts, the prevalence of any infection ranged from approximately 5 to 16% among PSAC, 6 to 23% among SAC, and 12 to 19% among WRA. Moderate-to-heavy intensity infection prevalence was highest in Kisoro (~15-26%), followed by Rubanda (<5%), and was ≤1% in other districts. A. lumbricoides and T. trichiura infections were largely confined to Kisoro and Rubanda, whereas hookworm was most common in other districts. The STH prevalence has decreased markedly in three districts in Uganda. Based on our findings, the national deworming program should consider decreasing PC distribution frequency in these districts per the World Health Organization guidelines. Efforts are needed to understand why the Kisoro and Rubanda districts did not demonstrate similar gains.

Detection and Prevalence of Soil Transmitted Helminths Contaminating Several Vegetables in Several Traditional Markets in Surabaya

A total of 100 fresh vegetable samples consisting of yardlong bean, cabbage, lettuce, and lemon basil were purchased from five traditional markets in Surabaya. Each sample was washed with tap water, water washing examined using flotation method to find soil-transmitted helminths. The overall prevalence of soil-transmitted helminths contamination was 41% (41/100). The most predominant parasite was hookworms (20%), followed by Strongyloides stercoralis larvae (14%) and Ascaris lumbricoides eggs (7%). The highest prevalence of contamination was found in lettuce, with a prevalence rate of 56% (14/25), while the lowest prevalence of contamination was found in yardlong bean, with a prevalence rate of 24% (6/25). Sequentially, the prevalence of soil-transmitted helminths contamination of fresh vegetable samples from Pabean traditional market (55%), Keputran traditional market (50%), Wonokromo traditional market (50%), Lakarsantri traditional market (35%) and Mulyosari traditional market (15%), respectively. The present study demonstrated that consumption of vegetables with parasite contamination in this area represents a potential route for the transmission of soil-transmitted helminths infection.

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.

Prevalence of Soil-Transmitted Helminths at Baseline and after Albendazole Treatment in the School-Age Children of Forcibly Displaced Myanmar Nationals in Bangladesh.

The forcibly displaced Myanmar nationals (FDMNs) known as Rohingya refugees are the largest group of stateless individuals globally. According to the emergencies humanitarian actors at the United Nations Office for the Coordination of Humanitarian Affairs, the worldwide refugee crisis involving FDMNs is intensifying at the fastest rate in history. Growing public health demands are being exacerbated by current difficulties in addressing poor access to health services, severe food shortages, and a lack of adequate housing. Infectious diseases constitute a major public health emergency in this vulnerable population. A study was carried out in FDMN children to investigate common soil-transmitted helminth (STH) infection at the time of enrollment and prospectively followed-up to 12 months after 2 doses albendazole treatment. At baseline, the prevalence of STH infection with at least one species was found to be 91.7% and 87.3% for Kato-Katz (KK) and quantitative polymerase chain reaction (qPCR) methods, respectively. Similarly, for follow-up children, the overall infection rate was 95.3% and 91.5%, respectively. Trichuris trichiura was the most predominant STH infection by both KK (baseline 87%, follow-up 89.1%) and qPCR (baseline 77.5%, follow-up 82.9%). The overall prevalence of stunting in the children was 37.8% at baseline and rose to 51.3% at 12 months. Alpha-1 antitrypsin (r = 0.13, P = 0.01) and myeloperoxidase (r = 0.12, P = 0.01) levels showed a positive correlation with Aascaris lumbricoides egg count per gram at baseline. An in-depth investigation is urgently needed to identify the underlying protective measures and the root cause of STH infections to improve the health of FDMN children.

Prevalence of Soil-Transmitted Helminths and Schistosoma mansoni among Schoolchildren across Altitudinal Gradients in Amhara National Regional State, Ethiopia.

Soil-transmitted helminths (STHs) and Schistosoma mansoni infections are common parasitic infections in sub-Saharan Africa. Their distributions vary across altitudes in Ethiopia. Hence, ongoing updates of infection risk factors and prevalence data are necessary for successful intervention. A school-based, cross-sectional study was conducted from October to December 2019 involving 530 schoolchildren who were recruited by systematic random sampling from Amhara Regional State. A structured questionnaire was used to collect data on sociodemographic, geographical and environmental factors. Stool samples were collected and processed by Ritchie's and Kato Katz techniques. Data were entered into EpiData and analyzed using SPSS. Descriptive statistics were used to compute prevalence, and logistic regression was used to assess factors associated with STHs and S. mansoni infections. Variables with P < 0.05 were considered statistically significant. Among 530 schoolchildren, 169 (31.9%) and 78 (14.7%) were infected with STHs and S. mansoni, respectively. The prevalence of STHs (40.2%) in the semi-highlands and S. mansoni (30.4%) in the lowlands was high. Infrequent shoes wearing, exposure to soil, not washing vegetables before eating, and living outside in lowland areas were significantly associated with STHs infections (P < 0.05). Schoolchildren who fetched water to irrigate fields, swam in rivers, and lived in lowland areas were significantly associated with S. mansoni infection (P < 0.05). In conclusion, prevalence rates of STHs and S. mansoni infections differed across altitudes in Amhara Regional State. Therefore, current control strategies including deworming and provision of clean water and education on sanitation and hygiene should be intensified and adapted to the local context.

Progress from morbidity control to elimination as a public health problem of schistosomiasis and the status of soil-transmitted helminth infection in Togo: a second impact assessment after ten rounds of mass drug administration

BackgroundDue to the burden of schistosomiasis (SCH) and soil-transmitted helminths (STH), Togo Ministry of Health launched a program for Preventive Chemotherapy Neglected Tropical Diseases (PC-NTDs) in 2009, initiating integrated mass drug administration (MDA) the following year for the three PC-NTDs: SCH, STH and onchocerciasis. Significant reduction of infection across the country was noted in 2015 during the first impact assessment, following 5 years of high-coverage MDA implemented at the sub-district level for SCH and district level for STH. After another 5 years of effective MDA, a second survey was conducted in 2021 to re-evaluate the situation of SCH and STH.MethodsA cross-section of school-aged children was taken across ten districts of Togo. A total of 302 schools in 92 sub-districts were sampled, with 24 school-aged children per school resulting in 7248 children surveyed. Urine samples were tested by haemastix® for Schistosoma haematobium, with urine filtration for the presence of eggs conducted on haematuria-positive samples. Stool samples were collected in a subset of 34 sub-districts in seven out of the ten surveyed districts, where STH and Schistosoma mansoni endemicity was high during the 2015 impact assessment. Duplicate (two) Kato-Katz analysis was performed for each stool sample. Sociodemographic and school-level water, sanitation and hygiene information was also collected.ResultsOverall, SCH prevalence was 5.90% (95% CI: 5.4–6.5), with 5.09% (95% CI: 4.64–5.67) for S. haematobium and 2.56% (95% CI: 1.98–3.29) for S. mansoni. STH prevalence was 19.7% (95% CI: 18.2–21.4), with 19.6% (95% CI: 18.1–21.3) hookworm, 0.08% (95% CI: 2.2–5.8) Trichuris trichiura and 0.04% (95% CI: 0.01–0.33) Ascaris lumbricoides. Compared to baseline, a significant reduction in both SCH (22.2% to 5.90%) and STH (29.2% t0 19.7%) prevalence was observed. Children aged 5–9 years were less infected than older peers aged 10–14 years: 4.76% vs. 7.53% (P < 0.01) for SCH and 17.2% vs. 23.0% (P < 0.01) for STH.ConclusionsAfter 10 years of high coverage integrated MDA, Togo has achieved low prevalence SCH infection through the sub-district MDA implementation with considerable infection heterogeneity within sub-districts. As STH infection has not reached a level where the infections are not a public health problem, the sub-district treatment strategy could also be adopted in addition to improvement of treatment coverage among preschool age children and hygiene and sanitation practices.Graphical

Low Prevalence of Soil-Transmitted Helminth Infections among Children in the States of Chhattisgarh and Himachal Pradesh, India, 2018.

Large-scale impact assessments of soil-transmitted helminth (STH) programs are essential for determining the frequency of mass drug administration (MDA). In baseline surveys, the prevalence of STHs in the Indian States of Chhattisgarh and Himachal Pradesh was 80.2% in 2015 and 29.0% in 2016, respectively. In 2018, we estimated the prevalence and intensity of STHs after six rounds of biannual MDA in Chhattisgarh and annual MDA in Himachal Pradesh. We conducted multistage cluster sampling surveys in preschool-age children (PSAC), school-age children (SAC), and adolescent cohorts. Stool samples from 3,033 respondents (PSAC, n = 625; SAC, n = 1,363; adolescents, n = 1,045) in Chhattisgarh and 942 respondents (PSAC, n = 192; SAC, n = 388; adolescents, n = 362) in Himachal Pradesh were examined for presence of STH infection using the Kato-Katz method. The overall cluster-adjusted prevalence in Chhattisgarh was 11.6% among all age groups (95% CI, 5.6-22.4)-an 85.5% reduction in the prevalence since 2015. Prevalence was not significantly different across cohorts (PSAC, 11.0% [95% CI, 5.0-22.6]; SAC, 10.9% [95% CI, 5.2-21.6]; adolescents, 12.8% [95% CI, 6.2-24.5]). Ascaris lumbricoides was the most common helminth, with most infections of light intensity. In Himachal Pradesh, only three STH infections were detected in 2018, resulting in a cluster-adjusted prevalence of 0.3% (95% CI, 0.1-1.7)-a 99.0% reduction in prevalence since 2016. All infections were of light intensity. Both states showed substantial improvements in socioeconomic and water, sanitation, and hygiene (WASH) indicators since the baseline surveys. Extensive reductions in prevalence and intensity are linked to sustained, high deworming coverage, as well as socioeconomic WASH indicators.

Soil-transmitted helminths: A critical review of the impact of co-infections and implications for control and elimination.

Researchers have raised the possibility that soil-transmitted helminth (STH) infections might modify the host's immune response against other systemic infections. STH infections can alter the immune response towards type 2 immunity that could then affect the likelihood and severity of other illnesses. However, the importance of co-infections is not completely understood, and the impact and direction of their effects vary considerably by infection. This review synthesizes evidence regarding the relevance of STH co-infections, the potential mechanisms that explain their effects, and how they might affect control and elimination efforts. According to the literature reviewed, there are both positive and negative effects associated with STH infections on other diseases such as malaria, human immunodeficiency virus (HIV), tuberculosis, gestational anemia, pediatric anemia, neglected tropical diseases (NTDs) like lymphatic filariasis, onchocerciasis, schistosomiasis, and trachoma, as well as Coronavirus Disease 2019 (COVID-19) and human papillomavirus (HPV). Studies typically describe how STHs can affect the immune system and promote increased susceptibility, survival, and persistence of the infection in the host by causing a TH2-dominated immune response. The co-infection of STH with other diseases has important implications for the development of treatment and control strategies. Eliminating parasites from a human host can be more challenging because the TH2-dominated immune response induced by STH infection can suppress the TH1 immune response required to control other infections, resulting in an increased pathogen load and more severe disease. Preventive chemotherapy and treatment are currently the most common approaches used for the control of STH infections, but these approaches alone may not be adequate to achieve elimination goals. Based on the conclusions drawn from this review, integrated approaches that combine drug administration with water, sanitation and hygiene (WASH) interventions, hygiene education, community engagement, and vaccines are most likely to succeed in interrupting the transmission of STH co-infections. Gaining a better understanding of the behavior and relevance of STH co-infections in the context of elimination efforts is an important intermediate step toward reducing the associated burden of disease.