Comparative assessment of intestinal helminths prevalence in Water, Sanitation and Hygiene (WASH) intervention and non-intervention communities in Abeokuta, Nigeria

Soil-transmitted helminthiasis among adolescents in Anaocha Local Government Area, Anambra State, Nigeria: Insights and recommendations for effective control

Over the past decade, Anambra State, Nigeria, has implemented mass administration of medicines (MAMs) to combat soil-transmitted helminthiasis (STH), a significant public health challenge in low-income regions. Nevertheless, these efforts have predominantly focused on pre-school and school-aged children, leaving a notable gap in understanding STH infection rates and the efficacy of these campaigns among secondary school adolescents, who have been excluded from this initiative. Our study aimed to address this critical knowledge gap by assessing soil-transmitted helminthiasis (STH) prevalence and contextual factors hindering effective control among adolescents in Anambra State, Nigeria. We actively engaged 443 adolescents with a mean age of 14 years in a school-based cross-sectional study in selected communities within the Anaocha Local Government Area from 8 February to 7 July 2023 following informed consent and assent procedures. Employing a stratified random sampling technique, we collected demographic data and assessed STH risk factors using a structured questionnaire hosted on the Kobo Toolbox platform. For quantitative analysis of STH infections, the Kato-Katz technique was used. Analysis was performed using SPSS version 25, incorporating descriptive statistics and multinomial logistic regression, with statistical significance set at p<0.05. Of the 443 (213 males (48.0%) and 230 females (52.0%) adolescents studied, the overall prevalence of STH observed was 35.2% (156/443). Ascaris lumbricoides was the prevalent STH species (16.9%), followed by Trichuris trichiura (1.4%) and hookworm (0.5%). Only light-intensity infection was observed. Mixed infections were observed in 16.5% of adolescents, involving A. lumbricoides and hookworm (10.8%), followed by A. lumbricoides and T. trichiura (3.2%) and all three STH (2.5%). The observed overall prevalence was not statistically significant with respect to gender (OR: 0.961; 95% CI: 0.651-1.420; p > 0.05) or age (OR: 0.686; 95% CI: 0.459-1.025; p>0.05). Class (grade level) (OR = 1.75, 95% CI: 1.25-2.45, p = 0.003), knowledge and transmission of STH infection (OR = 0.60, 95% CI: 0.42-0.86, p = 0.008), parental occupation (OR = 1.90, 95% CI: 1.35-2.67, p < 0.001), parents' literacy level (OR = 0.68, 95% CI: 0.48-0.96, p = 0.027), and the type of toilet (OR = 2.15, 95% CI: 1.54-3.00, p < 0.001) were all significantly correlated with STH infection. These findings highlight the role of adolescents in sustaining soil-transmitted helminthiasis (STH) transmission. Coupled with school-based deworming expansion, innovative improvements in water, sanitation, hygiene, and awareness can provide a cost-effective, sustainable solution for combatting STH infections in Anambra State.

Interventions to improve water, sanitation, and hygiene for preventing soil-transmitted helminth infection

BACKGROUND

It is estimated that 1.5 billion people are infected with soil-transmitted helminths (STHs) worldwide. Re-infection occurs rapidly following deworming, and interruption of transmission is unlikely without complementary control efforts such as improvements in water, sanitation, and hygiene (WASH) access and behaviours.

OBJECTIVES

To assess the effectiveness of WASH interventions to prevent STH infection.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 19 October 2021.

SELECTION CRITERIA

We included interventions to improve WASH access or practices in communities where STHs are endemic. We included randomized controlled trials (RCTs), as well as trials with an external control group where participants (or clusters) were allocated to different interventions using a non-random method (non-RCTs). We did not include observational study designs. Our primary outcome was prevalence of any STH infection. Prevalence of individual worms was a secondary outcome, including for Ascaris lumbricoides, Trichuris trichiura, hookworm (Ancylostoma duodenale or Necator americanus), or Strongyloides stercoralis. Intensity of infection, measured as a count of eggs per gram of faeces for each species, was another secondary outcome.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed titles and abstracts and full-text records for eligibility, performed data extraction, and assessed risk of bias using the Cochrane risk of bias assessment tool for RCTs and the EPOC tool for non-RCTs. We used a random-effects meta-analysis to pool study estimates. We used Moran's I² statistic to assess heterogeneity and conducted subgroup analyses to explore sources of heterogeneity. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 32 studies (16 RCTs and 16 non-RCTs) involving a total of 52,944 participants in the review. Twenty-two studies (14 RCTs (16 estimates) and eight non-RCTs (11 estimates)) reported on our primary outcome, prevalence of infection with at least one STH species. Twenty-one studies reported on the prevalence of A lumbricoides (12 RCTs and 9 non-RCTs); 17 on the prevalence of T trichiura (9 RCTs and 8 non-RCTs); 18 on the prevalence of hookworm (10 RCTs and 8 non-RCTs); and one on the prevalence of S stercoralis (1 non-RCT). Sixteen studies measured the intensity of infection for an individual STH type. Ten RCTs and five non-RCTs reported on the intensity of infection of A lumbricoides; eight RCTs and five non-RCTs measured the intensity of infection of T trichiura; and eight RCTs and five non-RCTs measured the intensity of hookworm infection. No studies reported on the intensity of infection of S stercoralis. The overall pooled effect estimates showed that the WASH interventions under study may result in a slight reduction of any STH infection, with an odds ratio (OR) of 0.86 amongst RCTs (95% confidence interval (CI) 0.74 to 1.01; moderate-certainty evidence) and an OR of 0.71 amongst non-RCTs (95% CI 0.54 to 0.94; low-certainty evidence). All six of the meta-analyses assessing individual worm infection amongst both RCTs and non-RCTs had pooled estimates in the preventive direction, although all CIs encapsulated the null, leaving the possibility of the null or even harmful effects; the certainty of the evidence ranged from very low to moderate. Individual studies assessing intensity of infection showed mixed evidence supporting WASH. Subgroup analyses focusing on narrow specific subsets of water, sanitation, and hygiene interventions did very little to elucidate which interventions might be better than others. Data on intensity of infection (e.g. faecal egg count) were reported in a variety of ways across studies, precluding the pooling of results for this outcome. We did not find any studies reporting adverse events resulting from the WASH interventions under study or from mass drug administration (MDA).

AUTHORS' CONCLUSIONS

Whilst the available evidence suggests that the WASH interventions under study may slightly protect against STH infection, WASH also serves as a broad preventive measure for many other diseases that have a faecal oral transmission route of transmission. As many of the studies were done in addition to MDA/deworming (i.e. MDA was ongoing in both the intervention and control arm), our data support WHO recommendations for implementation of improvements to basic sanitation and adequate access to safe water alongside MDA. The biological plausibility for improved access to WASH to interrupt transmission of STHs is clear, but WASH interventions as currently delivered have shown impacts that were lower than expected. There is a need for more rigorous and targeted implementation research and process evaluations in order that future WASH interventions can better provide benefit to users. Inconsistent reporting of the intensity of infection underscores the need to define the minimal, standard data that should be collected globally on STHs to enable pooled analyses and comparisons.

Trend Analysis of Intestinal Parasitic Infections at Debre Tabor Comprehensive Specialized Hospital, Northwest Ethiopia from 2017 to 2021: A Five-Year Retrospective Study

Introduction

In Ethiopia, intestinal parasites are common due to poverty, poor personal hygiene, poor environmental sanitation, overcrowding, a lack of safe drinking water, and a lack of knowledge. As a result, evaluating the intestinal parasite morbidity pattern in low-income countries such as Ethiopia is important for designing intestinal parasite intervention programs that minimize the illness burden. Despite the high prevalence of the disease in the Debre Tabor catchment areas, there is a lack of data on the trend of intestinal parasites. As a result, the study’s goal was to close the gap on the patterns of intestinal parasite infection for better control and intervention programs.

Methods

A retrospective study was conducted from 2017 to 2021 at Debre Tabor comprehensive specialized hospital to determine the trend of intestinal parasite infection. The findings of 7965 saline wet mount stool examinations were collected from the laboratory registration book by trained data collectors over the last five years. The study excluded any data that lacked sociodemographic characteristics and the year of the stool examination. Finally, the data were analyzed by SPSS version 25.

Results

The overall prevalence of intestinal parasites during the study period (2017–2021) was 2171 (27.3%) out of 7965 patients. Entamoeba histolytica/dispar (18.6%) was the predominant parasite, followed by Giardia lamblia (5.7%) and Ascaris lumbricoides (1%). Males (28.6%) were infected at a higher rate than females (26.2%) (P = 0.02). The intestinal parasite was reported in all age groups in the area, but the highest and the lowest prevalence were reported in the age groups of above 14 years (27.7%) and under five years (23.4%), respectively (P = 0.03).

Conclusion

The finding showed cyclic patterns of fluctuations in the prevalence of intestinal parasitic infections. Therefore, it is important to develop effective prevention and control strategies to prevent the distribution of intestinal parasites.

Prevalence of soil-transmitted helminth infection among children under 2 years from urban and rural settings in Ogun state, Nigeria: implication for control strategy

Background

Pre-school-aged children are always excluded in mass intervention policies for control of soil-transmitted helminths in Nigera. The need for evidence on infectivity of children in this age group cannot be overemphasized. This study seeks to determine the prevalence of STH among 103 children who are less than 2 years of age in an urban and rural area of Ogun State, Nigeria. This study through questionnaire administration also obtained relevant demographic information and hygiene behavior from parents of children recruited to this study.

Results

The overall prevalence of 69.9% was recorded, with Ascaris lumbricoides occurring as the most prevalent helminth (68.0%). This was followed by Hook worm (49.5%) and Trichris trichuria (18.5%). A significant increase in prevalence of hookworm was observed with increase in age (p < 0.05). Generally, A. Lumbricoides was found to be more prevalent as a single infection in the study population. Most of the T. Trichuria and hookworm infections were either in co-infections infections with A. Lumbricoides. The prevalence of A. Lumbricoides and Hookworm were significantly high in rural community when compared with urban (p < 0.05). Poor hygiene practices were common among the study participants.

Conclusions

The prevalence of STH infection is incredibly high in this age group that was for a long time considered as less important when it comes to burden due to STH. Therefore, there is a need to include them into future plans for control interventions.

Status of Intestinal Helminth Infection in Schools Implementing the Home-Grown School Feeding Program and the Impact of the Program on Pupils in Anambra State, Nigeria

PURPOSE

Intestinal helminthiasis among pupils is a major impediment to their well-being and development. This 2-year study determined how home-grown school feeding programme (HGSFP) impacted on pupils' school attendance and created opportunity for more children to assess interventions geared towards the prevention and possible elimination of intestinal helminthiasis.

METHODS

Faecal samples were collected from 1677 consented pupils and examined for helminths using Kato-Katz technique. Pupils were treated with 40 mg Levamisole (anti-helminthic) and re-examined. Structured questionnaires and focus group discussions were used to determine anthropometric indices and risk factors.

RESULTS

A 6% prevalence rate which was not significant with respect to sex or age was observed. Helminth parasites observed were Ascaris lumbricoides (4.4%), Trichuris trichiura (0.8%), Hookworm spp. (0.2%), and Taenia spp. (0.5%). Two pupils (1.98%) recorded high intensity of infection (epg) while 98.02% had light infection. Ascaris lumbricoides voided following treatment were 290. The Body Mass Index (BMI) indicated that infected pupils had lower values (14.6317) compared to uninfected pupils (19.2003). The HGSFP significantly improved school attendance by 30%. Lack of knowledge about transmission (P = 0.0004), hand hygiene (P = 0.01) and usage of toilet (P = 0.01) were risk factors observed.

CONCLUSION/SIGNIFICANCE

Intestinal helminthiasis remains a public health problem among pupils because environmental and behavioural risk factors persist. HGSFP improved school attendance and created opportunity for more inclusive participation of school-aged children for deworming. This has great potential in fast-tracking the elimination of intestinal helminthiasis. The present study consequently advocates the need to sustain HGSFP in schools.

Interventions promoting uptake of water, sanitation and hygiene (WASH) technologies in low- and middle-income countries: An evidence and gap map of effectiveness studies

Background

Lack of access to and use of water, sanitation and hygiene (WASH) cause 1.6 million deaths every year, of which 1.2 million are due to gastrointestinal illnesses like diarrhoea and acute respiratory infections like pneumonia. Poor WASH access and use also diminish nutrition and educational attainment, and cause danger and stress for vulnerable populations, especially for women and girls. The hardest hit regions are sub-Saharan Africa and South Asia. Sustainable Development Goal (SDG) 6 calls for the end of open defecation, and universal access to safely managed water and sanitation facilities, and basic hand hygiene, by 2030. WASH access and use also underpin progress in other areas such as SDG1 poverty targets, SDG3 health and SDG4 education targets. Meeting the SDG equity agenda to "leave none behind" will require WASH providers prioritise the hardest to reach including those living remotely and people who are disadvantaged.

Objectives

Decision makers need access to high-quality evidence on what works in WASH promotion in different contexts, and for different groups of people, to reach the most disadvantaged populations and thereby achieve universal targets. The WASH evidence map is envisioned as a tool for commissioners and researchers to identify existing studies to fill synthesis gaps, as well as helping to prioritise new studies where there are gaps in knowledge. It also supports policymakers and practitioners to navigate the evidence base, including presenting critically appraised findings from existing systematic reviews.

Methods

This evidence map presents impact evaluations and systematic reviews from the WASH sector, organised according to the types of intervention mechanisms, WASH technologies promoted, and outcomes measured. It is based on a framework of intervention mechanisms (e.g., behaviour change triggering or microloans) and outcomes along the causal pathway, specifically behavioural outcomes (e.g., handwashing and food hygiene practices), ill-health outcomes (e.g., diarrhoeal morbidity and mortality), nutrition and socioeconomic outcomes (e.g., school absenteeism and household income). The map also provides filters to examine the evidence for a particular WASH technology (e.g., latrines), place of use (e.g., home, school or health facility), location (e.g., global region, country, rural and urban) and group (e.g., people living with disability). Systematic searches for published and unpublished literature and trial registries were conducted of studies in low- and middle-income countries (LMICs). Searches were conducted in March 2018, and searches for completed trials were done in May 2020. Coding of information for the map was done by two authors working independently. Impact evaluations were critically appraised according to methods of conduct and reporting. Systematic reviews were critically appraised using a new approach to assess theory-based, mixed-methods evidence synthesis.

Results

There has been an enormous growth in impact evaluations and systematic reviews of WASH interventions since the International Year of Sanitation, 2008. There are now at least 367 completed or ongoing rigorous impact evaluations in LMICs, nearly three-quarters of which have been conducted since 2008, plus 43 systematic reviews. Studies have been done in 83 LMICs, with a high concentration in Bangladesh, India, and Kenya. WASH sector programming has increasingly shifted in focus from what technology to supply (e.g., a handwashing station or child's potty), to the best way in which to do so to promote demand. Research also covers a broader set of intervention mechanisms. For example, there has been increased interest in behaviour change communication using psychosocial "triggering", such as social marketing and community-led total sanitation. These studies report primarily on behavioural outcomes. With the advent of large-scale funding, in particular by the Bill & Melinda Gates Foundation, there has been a substantial increase in the number of studies on sanitation technologies, particularly latrines. Sustaining behaviour is fundamental for sustaining health and other quality of life improvements. However, few studies have been done of intervention mechanisms for, or measuring outcomes on sustained adoption of latrines to stop open defaecation. There has also been some increase in the number of studies looking at outcomes and interventions that disproportionately affect women and girls, who quite literally carry most of the burden of poor water and sanitation access. However, most studies do not report sex disaggregated outcomes, let alone integrate gender analysis into their framework. Other vulnerable populations are even less addressed; no studies eligible for inclusion in the map were done of interventions targeting, or reporting on outcomes for, people living with disabilities. We were only able to find a single controlled evaluation of WASH interventions in a health care facility, in spite of the importance of WASH in health facilities in global policy debates. The quality of impact evaluations has improved, such as the use of controlled designs as standard, attention to addressing reporting biases, and adequate cluster sample size. However, there remain important concerns about quality of reporting. The quality and usefulness of systematic reviews for policy is also improving, which draw clearer distinctions between intervention mechanisms and synthesise the evidence on outcomes along the causal pathway. Adopting mixed-methods approaches also provides information for programmes on barriers and enablers affecting implementation.

Conclusion

Ensuring everyone has access to appropriate water, sanitation, and hygiene facilities is one of the most fundamental of challenges for poverty elimination. Researchers and funders need to consider carefully where there is the need for new primary evidence, and new syntheses of that evidence. This study suggests the following priority areas:Impact evaluations incorporating understudied outcomes, such as sustainability and slippage, of WASH provision in understudied places of use, such as health care facilities, and of interventions targeting, or presenting disaggregated data for, vulnerable populations, particularly over the life-course and for people living with a disability;Improved reporting in impact evaluations, including presentation of participant flow diagrams; andSynthesis studies and updates in areas with sufficient existing and planned impact evaluations, such as for diarrhoea mortality, ARIs, WASH in schools and decentralisation. These studies will preferably be conducted as mixed-methods systematic reviews that are able to answer questions about programme targeting, implementation, effectiveness and cost-effectiveness, and compare alternative intervention mechanisms to achieve and sustain outcomes in particular contexts, preferably using network meta-analysis.

Epidemiology of Taenia saginata taeniosis/cysticercosis: a systematic review of the distribution in West and Central Africa

BACKGROUND

The zoonotic tapeworm Taenia saginata, although causing only minor discomfort in humans, is responsible for considerable economic losses in the livestock sector due to condemnation or downgrading of infected beef carcasses. An overview of current knowledge on the distribution and prevalence of this parasite in West and Central Africa is lacking.

METHODS

We conducted a systematic review, collecting information on published and grey literature about T. saginata taeniosis and bovine cysticercosis from 27 countries/territories in West and Central Africa, published between January 1st, 1990 and December 31st, 2017.

RESULTS

The literature search retrieved 1672 records, of which 51 and 45 were retained for a qualitative and quantitative synthesis, respectively. Non-specified human taeniosis cases were described for Nigeria, Cameroon, Senegal, Burkina Faso, Democratic Republic Congo, Guinea, and Ivory Coast (seven out of 27 countries/territories), while T. saginata taeniosis specifically was only reported for Cameroon. Most prevalence estimates for taeniosis ranged between 0-11%, while three studies from Nigeria reported prevalence estimates ranging between 23-50%. None of the studies included molecular confirmation of the causative species. The presence of bovine cysticercosis was reported for Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Democratic Republic Congo, Ghana, Guinea, Ivory Coast, Mali, Niger, Nigeria, Senegal, and Tristan da Cunha (14 out of 27 countries/territories). Prevalence estimates ranged between 0-29%.

CONCLUSIONS

Our systematic review has revealed that human taeniosis and bovine cysticercosis are seriously understudied in West and Central Africa. The high prevalence estimates of both conditions suggest an active dissemination of this parasite in the region, calling for a concerted One Health action from public health, veterinary health and food surveillance sectors.