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

Childhood undernutrition mediates the relationship between open defecation with anemia among Ethiopian children: a nationally representative cross-sectional study

BACKGROUND

Poor sanitation and/or open defecation are a significant public health problem in Ethiopia, where access to improved sanitation facilities is still limited. There is a growing body of literature about the effect of open defecation on children's linear growth failure. However, very few studies about the effects of open defecation on child anemia exist. In this study, we examine whether childhood undernutrition (i.e. stunting, wasting, and underweight) mediates the relationship between open defecation and childhood anemia in children aged 6-59 months in Ethiopia.

METHODS

We used pooled Ethiopia Demographic and Health Survey data (2005-2016) comprising 21,918 (weighted data) children aged 6-59 months. Anemia was defined as an altitude-adjusted hemoglobin (Hb) level of less than 11 g/deciliter (g/dl) for children under 5 years. Childhood undernutrition was assessed using height-for-age Z-scores (HAZ), weight-for-age Z-scores (WAZ), and weight-for-height Z-scores (WHZ) for stunting, wasting, and underweight respectively. Mediation effects were calculated using the bootstrap and the indirect effect was considered significant when the 95% bootstrap confidence intervals (95% CI) did not contain zero. Moreover, separate multilevel regression analyses were used to explore the statistical association between open defecation and child anemia, after adjusting for potential confounders.

RESULTS

Our analysis revealed that nearly half (49.6%) of children aged 6 to 59 months were anemic, 46.8% were stunted, 9.9% were wasted, and 29.5% were underweight. Additionally, 45.1% of children belonged to households that practiced open defecation (OD). Open defecation was associated with anemia (AOR: 1.28; 95% CI: 1.18-1.39) and it positively predicted anemia with direct effect of β = 0.233, p < 0.001. Childhood undernutrition showed a partial mediating role in the relationship between OD and anemia. Analyzing the indirect effects, results revealed that child undernutrition significantly mediated the relationship between open defecation and anemia (stunting (βindirect = 0.014, p < 0.001), wasting (βindirect = 0.009, p = 0.002), and underweight (βindirect = 0.012, p < 0.001)). When the mediating role of child undernutrition was accounted for, open defecation had a positive impact on anemia with a total effect of βtotal = 0.285, p < 0.001.

CONCLUSION

Open defecation showed a significant direct effect on anemia. Child undernutrition remarkably mediated the relationship between OD and anemia that further magnified the effect. This finding has an important programmatic implication calling for strengthened, accelerated and large-scale implementation of strategies to end open defecation and achieve universal access to sanitation in Ethiopia.

Access to basic sanitation facilities reduces the prevalence of anaemia among women of reproductive age in sub-saharan Africa

BACKGROUND

The prevalence (≈ 30%) of anaemia among women of reproductive age in Sub-Saharan Africa (SSA) is a significant concern. Additionally, less than half of households in the region have access to basic sanitation facilities, raising questions about the potential role of poor sanitation in increasing anaemia prevalence. To address this, we examined the relationship between access to basic sanitation facilities and the prevalence of anaemia among women of reproductive age in SSA.

METHODS

The study analysed cross-sectional household-level Demographic and Health Survey data from selected SSA countries. A total of 100,861 pregnant and non-pregnant women aged 15 to 49 from 27 countries were analysed. Access to basic sanitation and haemoglobin (Hb) levels were classified using WHO and UNICEF standards. To examine the link between access to basic sanitation facilities and the prevalence of anaemia, a multilevel regression analysis was conducted, which adjusted for country fixed-effects to ensure that the findings were not biassed by variations in country-level factors.

RESULTS

Nearly 37% (95% CI: 36.4, 37.9) of households had access to basic sanitation facilities, and 41% (95% CI: 40.8, 42.1) of women had Hb levels that indicated anaemia. Women with access to basic sanitation had a lower risk of anaemia than those without access (AOR = 0.95; 95% CI: 0.93, 0.98, p < 0.01). Factors, including maternal age, education, marital status, breastfeeding, health insurance enrollment, and wealth group, were also associated with anaemia prevalence.

CONCLUSIONS

Anaemia is a severe public health problem among women of reproductive age across all 27 SSA countries analysed, with nearly four in ten being affected. Access to basic sanitation facilities was associated with a reduced anaemia risk. However, only slightly over a third of households had access to such facilities. Further research is required to examine the underlying mechanisms and inform effective interventions.

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

BACKGROUND

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.

METHODOLOGY/PRINCIPAL FINDINGS

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.

CONCLUSIONS/SIGNIFICANCE

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.

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

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

High Prevalence of Hookworm Species and Associated Factors among Soil-Transmitted Helminth-Infected Household Contacts in Burie Zuria District, Northwest Ethiopia: A Community-Based Cross-Sectional Study

Background

Soil-transmitted helminths (STHs) are parasitic worms that are widely distributed in the tropical and subtropical regions. In Ethiopia, one of the tropical countries, STH infections are high and cause a huge burden. Several STH species show a pattern of household clustering with regard to prevalence and intensity. However, there is a scarcity of data on the status of STH infection among family contacts of STH-infected individuals in Ethiopia in general and in the study area in particular.

Objective

This study is aimed at assessing the prevalence of soil-transmitted helminths and associated factors among STH-infected household contacts in Burie Zuria district, northwest Ethiopia.

Method

A community-based cross-sectional study was conducted among 422 study participants from March to May 2021. Study participants were traced to their residences by following STH-infected patients. A convenient sampling technique was used to recruit the study participants. The stool samples were processed using duplicate Kato-Katz thick smears and a modified Ritchie's technique. The data were entered and analyzed using the Statistical Package for Social Sciences, version 26 of the software package. A P value <0.05 was considered a statistically significant association.

Results

The overall prevalence of STHs was 36.5% (95% CI: 31.7%-41.5%). Two STHs, namely hookworm species (33.2%, 140/422) at (95% CI: 28.9%-37.8%) and Ascaris lumbricoides (4.3%, 18/422) at (95% CI: 2.7%-6.6%), were identified, with a double infection of 2.6% (4/154) at (95% CI: 1.0%-6.5%). Almost the majority (96.9%) of hookworm species and all Ascaris lumbricoides infections were categorized under a light intensity of infection. Family size >5 (AOR = 1.74; 95% CI: 1.15-2.60; P = 0.008) and lack of latrine facility (AOR = 1.86; 95% CI: 1.17-2.90; P = 0.02) were significantly associated with STH infections.

Conclusion

A high prevalence of hookworms was found in the study area, where the majority of the study participants were adults. This finding may provide a basis for revising the school-based deworming programs that exclude the adult population. Public health interventions like accessing latrines, health education, and deworming programs should be regularly implemented for all age groups in the areas.

Prevalence and Associated Risk Factors of Soil-Transmitted Helminth Infections among Schoolchildren around Lake Tana, Northwest Ethiopia

Background

Soil-transmitted helminths (STHs) are among the most common neglected tropical diseases widely distributed in tropical countries with poor socioeconomic development. Ascaris lumbricoides, Trichuris trichiura, and hookworm are the three major STHs. This study aimed to determine the prevalence of STHs and associated risk factors among schoolchildren in selected primary schools around Lake Tana, Northwestern Ethiopia.

Methods

A school-based cross-sectional study was conducted from February to May 2021 involving 337 study participants. A systematic random sampling method was utilized to select the study participants from the selected schools. Data related to sociodemographic characteristics of the study participants and risk factors for STH infections were collected using a pretested questionnaire. Stool samples were collected in sterile plastic containers from each participant and processed using Kato-Katz thick fecal smear and Ritchie's concentration techniques. The data were analyzed using the Statistical Package for Social Sciences software tool version 23, and factors with a p < 0.05 were considered as statistically significant.

Results

The overall prevalence of STH infection was 38.3% (95% CI: 33.1-43.7). Hookworm infection was the predominant STH infection, which was detected in 26.1% schoolchildren followed by A. lumbricoides (14.8%) and T. trichiura (1.5%). Most of the study subjects (34.1%) had single infections, whereas only 4.2% study subjects had multiple helminthic infections. Among the risk factors considered in the study, lack of shoe wearing habit (adjusted odds ratio [AOR]=29.5; 95% confidence interval [CI]=6.59-132.55; p < 0.001), lack of knowledge on the prevention and control methods (AOR = 5.41; 95% CI = 2.44-11.98; p < 0.001), engagement in irrigation activities (AOR = 2.14; 95% CI = 1.02-4.57, p = 0.049), lack of toilet (AOR = 3.06; 95% CI = 1.31-7.16; p = 0.01), children grades of 5-8 (AOR = 2.62; 95% CI = 1.26-5.43; p = 0.01), playing on soils (AOR = 5.90; 95% CI = 2.79-12.49; p < 0.001), lack of fingernail trimming habit (AOR = 3.21; 95% CI = 1.57-6.55; p = 0.001), and male gender (AOR = 2.28; 95% CI: 1.19-4.39; p = 0.013) were significant explanatory factors for STH infection among schoolchildren in the study area.

Conclusions

The present study showed that STHs were common among schoolchildren around Lake Tana. Therefore, education on personal and environmental hygiene should be taken into account to reduce the prevalence of STH infection in the study area.

Urude R, Kadimbo J, Danboyi J, Miri E, Nute AW, Rakers L, Nebe O, Anyaike C, Weiss P, S. Noland G, Richards F. Impact of Three to Five Rounds of Mass Drug Administration on Schistosomiasis and Soil-Transmitted Helminths in School-Aged Children in North-Central Nigeria

Nasarawa and Plateau states of north-central Nigeria have implemented programs to control schistosomiasis (SCH) and soil-transmitted helminths (STH) in children since the 1990s. Statewide mapping surveys were conducted in 2013, when 11,332 school-aged children were sampled from 226 schools. The local government areas (LGAs) then received varying combinations of mass drug administration (MDA) for the next 5 years. We revisited 196 (87%) schools in 2018 plus an additional six (202 schools in total), sampling 9,660 children. We calculated overall prevalence and intensity of infection and evaluated associations with gender; age; behaviors; water, sanitation, and hygiene (WASH); and treatment regimen. Urine heme detection dipsticks were used for Schistosoma hematobium in both surveys, with egg counts added in 2018. Stool samples were examined by Kato-Katz for Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni, and hookworm. Schistosomiasis prevalence among sampled students dropped from 12.9% (95% confidence interval [CI]: 11.1-14.9%) to 9.0% (95% CI: 7.5-10.9%), a statistically significant change (P < 0.05). In 2018, eight LGAs still had > 1% of children with heavy-intensity schistosome infections. Prevalence of STH infection did not significantly change, with 10.8% (95% CI: 9.36-12.5%) of children positive in 2013 and 9.4% (95% CI: 8.0-10.9%) in 2018 (P = 0.182). Heavy-intensity STH infections were found in < 1% of children with hookworm, and none in children with A. lumbricoides or T. trichiura in either study. The WASH data were collected in 2018, indicating 43.6% of schools had a latrine and 14.4% had handwashing facilities. Although progress is evident, SCH remains a public health problem in Nasarawa and Plateau states.

Feature importance: Opening a soil-transmitted helminth machine learning model via SHAP

In the field of landscape epidemiology, the contribution of machine learning (ML) to modeling of epidemiological risk scenarios presents itself as a good alternative. This study aims to break with the ”black box” paradigm that underlies the application of automatic learning techniques by using SHAP to determine the contribution of each variable in ML models applied to geospatial health, using the prevalence of hookworms, intestinal parasites, in Ethiopia, where they are widely distributed; the country bears the third-highest burden of hookworm in Sub-Saharan Africa. XGBoost software was used, a very popular ML model, to fit and analyze the data. The Python SHAP library was used to understand the importance in the trained model, of the variables for predictions. The description of the contribution of these variables on a particular prediction was obtained, using different types of plot methods. The results show that the ML models are superior to the classical statistical models; not only demonstrating similar results but also explaining, by using the SHAP package, the influence and interactions between the variables in the generated models. This analysis provides information to help understand the epidemiological problem presented and provides a tool for similar studies.

Environmental characteristics around the household and their association with hookworm infection in rural communities from Bahir Dar, Amhara Region, Ethiopia

Soil-Transmitted Helminths (STH) are highly prevalent Neglected Tropical Disease in Ethiopia, an estimated 26 million are infected. Geographic Information Systems and Remote Sensing (RS) technologies assist data mapping and analysis, and the prediction of the spatial distribution of infection in relation to environmental variables. The influence of socioeconomic, environmental and soil characteristics on hookworm infection at the individual and household level is explored in order to identify spatial patterns of infection in rural villages from Zenzelema (Amhara region). Inhabitants greater than 5 years old were recruited in order to assess the presence of STH. Socioeconomic and hookworm infection variables at the household level and environmental variables and soil characteristics using RS were obtained. The dominant STH found was hookworm. Individuals which practiced open defecation and those without electricity had a significant higher number of hookworm eggs in their stool. Additionally, adults showed statistically higher hookworm egg counts than children. Nonetheless, the probability of hookworm infection was not determined by socioeconomic conditions but by environmental characteristics surrounding the households, including a combination of vigorous vegetation and bare soil, high temperatures, and compacted soils (high bulk density) with more acidic pH, given a pH of 6.0 is optimal for hatching of hookworm eggs. The identification of high-risk environmental areas provides a useful tool for planning, targeting and monitoring of control measures, including not only children but also adults when hookworm is concerned.