Sentinel surveillance of soil-transmitted helminthiasis in preschool-aged and school-aged children in selected local government units in the Philippines: follow-up assessment

A review of health education activities targeting schoolchildren for the control of soil-transmitted helminthiasis in Southeast Asia, with emphasis upon the Magic Glasses approach

Soil-transmitted helminths continue to be a serious problem causing disease and morbidity globally. Children, mostly school-aged, are more at risk of these infections. The main strategy for control remains to be the mass drug administration (MDA) of antihelminthic drugs. With the limitation of MDA to prevent re-infection, the need for additional approaches such as hygiene education and improvements in water, sanitation and hygiene (WASH) infrastructure are required. Although the importance of health education as a crucial component of an integrated approaches to STH control is highlighted, this component has often been disregarded because the other more complex solutions have been the focus of most studies and programmes. We performed literature searches from four bibliographic databases - Scopus, PubMed, Web of Science and Cochrane Library - to determine availability of studies on the impact of health education interventions targeting STH infections on schoolchildren in Southeast Asia. Our review found only three studies that evaluated health education interventions targeting children. The current lack of evidence in this area suggests the need for more studies assessing the impact of health education intervention for STH control. A successful health education programme for STH called "The Magic Glasses" has been developed targeting schoolchildren in China and the Philippines. This public health intervention displayed significant impact in terms of improving knowledge, attitude and practices, reducing prevalence of STH infections in schoolchildren and encouraging compliance to MDA. This article details the successes and benefits of the Magic Glasses programme as a promising control tool for STH in the Southeast Asian region.

High prevalence of soil-transmitted helminth infections in Myanmar schoolchildren

BACKGROUND

Achieving the elimination of soil-transmitted helminth (STH) infections requires a sufficient understanding of the current epidemiological status of STH endemicity. We aimed to examine the status of STH in Myanmar - a country with the eighth highest STH prevalence in the world, 10 years after instigation of the national deworming programme.

METHODS

In August 2016 we screened for STH infections using Kato Katz (KK) microscopy and real-time PCR (qPCR) in schoolchildren from the Bago Region township of Phyu, a STH sentinel site in Myanmar. Ten schools were randomly selected, and one stool sample each from a total of 264 students was examined. Prevalence and intensity of infection were calculated for each STH.

RESULTS

High prevalence of STH was identified in the study area with 78.8% of the schoolchildren infected with at least one STH by qPCR, and 33.3% by KK. The most prevalent STH was Trichuris trichiura, diagnosed by both KK (26.1%) and qPCR (67.1%), followed by Ascaris lumbricoides (15.5% KK; 54.9% qPCR). No hookworm infections were identified by KK; however, the qPCR analysis showed a high prevalence of Ancylostoma sp. infection (29.6%) with few Necator americanus (1.1%) infections.

CONCLUSIONS

Despite bi-annual deworming of schoolchildren in the fourth-grade and below, STH prevalence remains stubbornly high. These results informed the expansion of the Myanmar National STH control programme to include all school-aged children by the Ministry of Health and Sports in 2017, however further expansion to the whole community should be considered along with improving sanitation and hygiene measures. This would be augmented by rigorous monitoring and evaluation, including national prevalence surveys.

Soil-transmitted helminth infections and nutritional indices among Filipino schoolchildren

BACKGROUND

Soil-transmitted helminth (STH) infections are still prevalent among schoolchildren in the Philippines. We evaluated the risk factors associated with STH and the relationship between STH and nutritional indices among schoolchildren aged 9-10 years in Laguna province, the Philippines.

METHODS

We used the baseline data from 40 schools enrolled in a randomised controlled trial of the Magic Glasses Philippines health education package. Data on demographic and socio-economic variables, and STH related knowledge, attitudes and practices, were obtained through a questionnaire. Stool samples were collected and assessed for STH egg presence using the Kato-Katz technique. Haemoglobin levels and height and weight of study participants were also determined. The generalized estimating equations approach was used to construct logistic regression models to assess STH-associated risk factors, and the association between any STH infection and anaemia, child stunting, wasting and being underweight. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000508471).

FINDINGS

Among 1,689 schoolchildren, the prevalence of any STH was 23%. The prevalence of anaemia, stunting, being underweight and wasting was 13%, 20.2%, 19% and 9.5%, respectively. Age, socio-economic status, rural/urban classification of schools and knowledge of STH were significant risk factors for acquiring a STH infection. Moreover, infections with any STH were significantly associated with stunting (P = <0.001) and being underweight (P = <0.003), but not wasting (P = 0.375) or anaemia (P = 0.462) after controlling for confounding covariates.

CONCLUSION

The study findings emphasise the need for sustainable deworming in tandem with other measures such as the provision of health education, improvements in sanitation and hygiene, and nutritional programs in order to control STH infections and improve morbidity outcomes in schoolchildren.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12616000508471).

High burden of soil-transmitted helminth infections, schistosomiasis, undernutrition, and poor sanitation in two Typhoon Haiyan-stricken provinces in Eastern Philippines

This study aimed to describe: 1) soil-transmitted helminthiasis (STH) and schistosomiasis prevalence and intensity in preschool-age children (PSAC) and school-age children (SAC), 2) schistosomiasis seroprevalence in SAC, 3) undernutrition prevalence in SAC, 4) sanitary toilet coverage in households, and 5) association between STH, Schistosoma japonicum exposure, nutritional status, and sanitation. PSAC and SAC in two Haiyan-stricken provinces were examined using Kato-Katz technique and ELISA Antibody test. Anthropometric and hemoglobin measurements were also obtained. The reported sanitary toilet coverage was validated in a survey. The prevalence of any STH in PSAC and SAC was 50.2% and 41.3%, respectively. Moderate-heavy intensity (MHI) STH prevalence in PSAC and SAC was 20.8% and 5.9%, respectively. The prevalence of any STH, MHI STH, ascariasis, MHI ascariasis, and MHI trichuriasis was significantly higher in PSAC. Stunting, underweight, wasting, overweight/obesity, and anemia prevalence was 38.4%, 24.5%, 4.8%, 2.7%, and 34.7% in PSAC, while the prevalence was 34.3%, 21.6%, 8.7%, 3.0%, and 19.2% in SAC, respectively. Anemia and wasting prevalence were significantly higher in PSAC and SAC, respectively. There were five schistosomiasis cases found (0.8% prevalence), while schistosomiasis seroprevalence was 60.1%. Validated and reported sanitary toilet coverage was significantly different in eight out of 13 barangays. Stunting and anemia were associated with STH. STH and anemia prevalence were significantly higher in non-ZOD barangays. High STH burden in PSAC and SAC persists. A more coordinated response addressing STH, undernutrition, and WASH in disaster-stricken areas will require strengthening local health systems and promoting intersectoral collaboration.

The control of soil-transmitted helminthiases in the Philippines: the story continues

Background

Soil-transmitted helminth (STH) infections have long been an important public health concern in the Philippines. In this review, we describe the current status of STH infections there and highlight the control efforts undertaken to reduce STH burden.

Main text

A nationwide STH mass drug administration (MDA) programme was started in 2006 but the overall STH prevalence remains stubbornly high across the Philippines, ranging from 24.9% to 97.4%. The continued increase in the prevalence may have been due to the challenges related to MDA implementation which include the lack of people’s awareness about the importance of regular treatment, misconceptions about the MDA strategy, lack of confidence on the drugs used, fear of adverse events and general distrust of government programs. There are existing water, sanitation and hygiene (WASH) programmes implemented in communities [e.g., Community-Led Total Sanitation (CLTS) program and providing toilet bowls and provision of subsidy for latrine construction] and schools [e.g., WASH in School (WINS) program], but sustained implementation is required to achieve expected outcomes. Although WASH in general is being taught in schools, integration of STH as a disease and community problem in the current public elementary school curriculum is still inadequate. The Integrated Helminth Control Program (IHCP) currently implemented in the country, which is focused on improved sanitation and personal hygiene, health education and preventive chemotherapy, will require continuous appraisal. The sustainability of this programme still continues to be a challenge.

Conclusions

Despite the major efforts to control STH infections for almost two decades in the Philippines, persistently high STH prevalence has been reported across the country, which is likely due to suboptimal MDA coverage and limitations in WASH and health education programs. Sustainable delivery of integrated control approaches will continue to play a pivotal role in the control and elimination of STH in the Philippines.

Graphic abstract

Determining the Impact of a School-Based Health Education Package for Prevention of Intestinal Worm Infections in the Philippines: Protocol for a Cluster Randomized Intervention Trial

Background

Repeated mass drug administration (MDA) of antihelminthics to at-risk populations is still the main strategy for the control of soil-transmitted helminth (STH) infections. However, MDA, as a stand-alone intervention, does not prevent reinfection. Accordingly, complementary measures to prevent STH reinfection, such as health education and improved sanitation, as part of an integrated control approach, are required to augment the effectiveness of MDA for optimal efficiency and sustainability.

Objective

The aim of this study is to determine the impact and generalizability of a school-based health education package entitled The Magic Glasses for STH prevention in the Philippines.

Methods

We conducted a cluster randomized controlled intervention trial, involving 2020 schoolchildren aged 9-10 years, in 40 schools in Laguna Province, Philippines, to evaluate the impact of the school-based health education package for the prevention of STHs. The trial was conducted over the course of 1 year (June 2016 to July 2017). A total of 20 schools were randomly assigned to the intervention arm, in which The Magic Glasses Philippines health education package was delivered with the standard health education activities endorsed by the Philippines Department of Health (DOH) and the Department of Education (DepEd). The other 20 schools comprised the control arm of the study, where the DOH/DepEd’s standard health education activities were done. At baseline, parasitological assessments and a knowledge, attitude, and practice survey were carried out in all schools. In addition, height, weight, and hemoglobin levels were obtained from each child (after parental consent), and their school attendance and academic performance in English and mathematics were accessed from the school records. The baseline and 2 follow-up surveys were completed using the same study measurements and quality-control assessments.

Results

Key results from this cluster randomized intervention trial will shed light on the impact that The Magic Glasses health education package will have against STH infections in schoolchildren in the province of Laguna, located on the Island of Luzon, in the Calabarzon Region of the Philippines.

Conclusions

The results of the trial will be used to assess the generalizability of the impact of The Magic Glasses health education package in different epidemiological and cultural settings, providing evidence for translation of this health education package into public health policy and practice in the Asian region and beyond.

Trial Registration

Australian New Zealand Clinical Trials Registry number ACTRN12616000508471; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368849

International Registered Report Identifier (IRRID)

DERR1-10.2196/18419

Health and Education Officials' Perspectives on the Impact of Typhoon Haiyan on Mass Drug Administration for Soil-Transmitted Helminth Infections in the Philippines

OBJECTIVES

In the Philippines, morbidity control of soil-transmitted helminth (STH) infections is done through mass drug administration (MDA) of anthelmintics to school-age children (SAC). In 2013, the Philippines was devastated by the deadliest cyclone ever recorded, Typhoon Haiyan. The study aimed to understand the impact of Typhoon Haiyan on the MDA of anthelmintics to SAC in the provinces of Capiz and Iloilo in the Philippines from the perspectives of local health and education officials.

METHODS

The study was conducted in the municipalities of Panay and Pilar in Capiz and the municipalities of Estancia and Sara in Iloilo, areas that were devastated by Typhoon Haiyan. Qualitative, semi-structured key informant interviews were conducted with 16 total participants, which included officials of the Department of Health, Department of Education, and concerned local government units. All interviews were transcribed verbatim and coded in an open, iterative manner. Codes were reviewed to identify patterns and themes.

RESULTS

Participants described the following themes: (1) their perception that the typhoon had no effect on the MDA program or on resources necessary to complete the program; (2) the program's simple design allowed for 1-time administration to a pre-assembled population; (3) the program allowed a sense of community cohesiveness; (4) the program served as a vehicle for altruism, particularly regarding helping needy children, in this time of calamity.

CONCLUSIONS

Our informants perceived that the MDA program in Region VI was not affected by Typhoon Haiyan. They attributed the resilience to the program's simple procedure, attitudes of altruism, program importance, and community cohesiveness. Despite Typhoon Haiyan's mass destruction of infrastructure and livelihood leading to incredible challenges, mobilization of the community allowed for the continuation and successful implementation of the MDA program. The experience of Region VI may serve as a model for other low- and middle-income countries prone to natural disasters.

Ivermectin Dosing Strategy to Achieve Equivalent Exposure Coverage in Children and Adults

Ivermectin is a commonly used broad-spectrum antiparasitic drug, yet doses that produce consistent exposure coverage across age have not been characterized, and no data are available in children weighing < 15 kg. First, a population pharmacokinetic model is developed based on data from 200 children and 11 adults, treated with 100-600 μg/kg ivermectin. Second, model-based simulations are performed to identify a dosing strategy that achieves equivalent exposure coverage in children and adults. Median (90% confidence interval) clearance of 0.346 (0.12-0.73) L/hour/kg in pre-school-aged (2-5 years) children is similar to 0.352 (0.17-0.69) L/hour/kg in school-aged (6-12 years) children but higher than in adults (0.199 (0.10-0.31) L/hour/kg), resulting in significantly lower exposure in children following a 200 μg/kg dose. Simulations indicate that a dose increase to 300 and 250 μg/kg in children aged 2-5 and 6-12 years, respectively, will achieve equivalent ivermectin exposure coverage in children and adults.

Status of soil-transmitted helminth infections in schoolchildren in Laguna Province, the Philippines: Determined by parasitological and molecular diagnostic techniques

BACKGROUND

Soil-transmitted helminths (STH) are the most common parasitic infections in impoverished communities, particularly among children. Current STH control is through school-based mass drug administration (MDA), which in the Philippines is done twice annually. As expected, MDA has decreased the intensity and prevalence of STH over time. As a result, the common Kato Katz (KK) thick smear method of detecting STH is less effective because it lacks sensitivity in low intensity infections, making it difficult to measure the impact of deworming programs.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study was carried out over a four-week period from October 27, 2014 until November 20, 2014 in Laguna province, the Philippines. Stool samples were collected from 263 schoolchildren, to determine the prevalence of STH and compare diagnostic accuracy of multiplex quantitative polymerase chain reaction (qPCR) with the KK. A large discrepancy in the prevalence between the two techniques was noted for the detection of at least one type of STH infection (33.8% by KK vs. 78.3% by qPCR), Ascaris lumbricoides (20.5% by KK vs. 60.8% by qPCR) and Trichuris trichiura (23.6% by KK vs. 38.8% by qPCR). Considering the combined results of both methods, the prevalence of at least one type of helminth infection, A. lumbricoides, and T. trichiura were 83.3%, 67.7%, and 53.6%, respectively. Sensitivity of the qPCR for detecting at least one type of STH infection, A. lumbricoides, and T. trichiura were 94.1%, 89.9%, and 72.3% respectively; whereas KK sensitivity was 40.6%, 30.3%, and 44.0%, respectively. The qPCR method also detected infections with Ancylostoma spp. (4.6%), Necator americanus (2.3%), and Strongyloides stercoralis (0.8%) that were missed by KK.

CONCLUSION/SIGNIFICANCE

qPCR may provide new and important diagnostic information to improve assessment of the effectiveness and impact of integrated control strategies particularly in areas where large-scale STH control has led to low prevalence and/or intensity of infection.

Differential effect of mass deworming and targeted deworming for soil-transmitted helminth control in children: a systematic review and meta-analysis

BACKGROUND

Soil-transmitted helminth infections are a major global health issue, causing substantial morbidity in the world's poorest populations. Regular delivery of anthelmintic drugs is the mainstay for global soil-transmitted helminth control. Deworming campaigns are often targeted to school-aged children, who are at high risk of soil-transmitted-helminth-associated morbidity. However, findings from modelling studies suggest that deworming campaigns should be expanded community-wide for effective control of soil-transmitted helminth transmission. We aimed to do a systematic review and meta-analysis to compare the effect of mass (community-wide) and targeted (children only) anthelmintic delivery strategies on soil-transmitted helminth prevalence in school-aged children.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, and Web of Science for articles published on or before Nov 5, 2015, reporting soil-transmitted helminth prevalence before and after distribution of albendazole or mebendazole, either targeted to children or delivered to the whole community. We excluded studies in which drug delivery was restricted to infected individuals or to a subset of the community or school, or if follow-up time was less than 3 months or greater than 18 months after drug delivery. We extracted data on study year, country, drug administration strategy, drug dose, number of deworming rounds, treatment coverage, diagnostic method, follow-up interval, and soil-transmitted helminth prevalence before and after treatment. We used inverse variance weighted generalised linear models, with prevalence reduction as the outcome variable, to examine the effect of mass versus targeted drug administration, as well as baseline prevalence, number of drug doses, and follow-up time. This study is registered with PROSPERO, number CRD42016026929.

FINDINGS

Of 10 538 studies identified, 56 studies were eligible for the systematic review and 38 of these were included in meta-analysis. Results of the regression models showed that mass deworming led to a significantly greater reduction in prevalence in children than targeted deworming, for both hookworm (odds ratio 4·6, 95% CI 1·8-11·6; p=0·0020) and Ascaris lumbricoides (16·4, 2·1-125·8; p=0·0092), with no effect seen for Trichuris trichiura. There was significant heterogeneity across studies; for targeted studies I² was 97% for A lumbricoides and hookworm, and 96% for T trichiura, and for mass studies, I² was 89% for A lumbricoides, 49% for hookworm, and 66% for T trichiura.

INTERPRETATION

The results of this meta-analysis suggest that expanding deworming programmes community-wide is likely to reduce the prevalence of soil-transmitted helminths in the high-risk group of school-aged children, which could lead to improved morbidity outcomes. These findings are in support of recent calls for re-evaluation of global soil-transmitted helminth control guidelines.

FUNDING

None.

Unprogrammed deworming in the Kibera slum, Nairobi: implications for control of soil-transmitted helminthiases

BACKGROUND

Programs for control of soil-transmitted helminth (STH) infections are increasingly evaluating national mass drug administration (MDA) interventions. However, "unprogrammed deworming" (receipt of deworming drugs outside of nationally-run STH control programs) occurs frequently. Failure to account for these activities may compromise evaluations of MDA effectiveness.

METHODS

We used a cross-sectional study design to evaluate STH infection and unprogrammed deworming among infants (aged 6-11 months), preschool-aged children (PSAC, aged 1-4 years), and school-aged children (SAC, aged 5-14 years) in Kibera, Kenya, an informal settlement not currently receiving nationally-run MDA for STH. STH infection was assessed by triplicate Kato-Katz. We asked heads of households with randomly-selected children about past-year receipt and source(s) of deworming drugs. Local non-governmental organizations (NGOs) and school staff participating in school-based deworming were interviewed to collect information on drug coverage.

RESULTS

Of 679 children (18 infants, 184 PSAC, and 477 SAC) evaluated, 377 (55%) reported receiving at least one unprogrammed deworming treatment during the past year. PSAC primarily received treatments from chemists (48.3%) or healthcare centers (37.7%); SAC most commonly received treatments at school (55.0%). Four NGOs reported past-year deworming activities at 47 of >150 schools attended by children in our study area. Past-year deworming was negatively associated with any-STH infection (34.8% vs 45.4%, p = 0.005). SAC whose most recent deworming medication was sourced from a chemist were more often infected with Trichuris (38.0%) than those who received their most recent treatment from a health center (17.3%) or school (23.1%) (p = 0.05).

CONCLUSION

Unprogrammed deworming was received by more than half of children in our study area, from multiple sources. Both individual-level treatment and unprogrammed preventive chemotherapy may serve an important public health function, particularly in the absence of programmed deworming; however, they may also lead to an overestimation of programmed MDA effectiveness. A standardized, validated tool is needed to assess unprogrammed deworming.

Parasitological and nutritional status of school-age and preschool-age children in four villages in Southern Leyte, Philippines: Lessons for monitoring the outcome of Community-Led Total Sanitation

While preventive chemotherapy remains to be a major strategy for the prevention and control of soil-transmitted helminthiases (STH), improvements in water, sanitation, and hygiene (WASH) comprise the long-term strategy to achieve sustained control of STH. This study examined the parasitological and nutritional status of school-age and preschool-age children in four villages in Southern Leyte, Philippines where two of the villages attained Open-Defecation-Free (ODF) status after introduction of Community-Led Total Sanitation (CLTS). A total of 341 children (89.0% of the total eligible population) submitted stool samples which were examined using the Kato-Katz technique. Results showed that 27.9% of the total stool samples examined had at least one type of STH (cumulative prevalence), while 7.9% had moderate-heavy intensity infections. Between the two villages where CLTS was introduced, Buenavista had a significantly higher cumulative prevalence of STH at 67.4% (p<0.001) and prevalence of moderate-heavy intensity STH at 23.5% (p=0.000), while Caubang had a significantly lower cumulative prevalence at 4.9% and prevalence of moderate-heavy intensity at 1.8%. On the other hand, the non-CLTS villages of Bitoon and Saub had similar rates for cumulative prevalence (16.7% and 16.8%, respectively; p=0.984) and prevalence of moderate-heavy intensity STH (2.0% and 3.1%, respectively; p=1.000). The findings may be explained by factors that include possible reversion to open defecation, non-utilization of sanitary facilities, and mass drug administration (MDA) coverage, although further studies that can accurately assess the impact of CLTS are recommended. While this study was descriptive, the data indicate no clear pattern among the parasitological and nutritional parameters, as well as the presence of CLTS in the village, suggesting the need to monitor the ODF status of villages on a regular basis even after the end of CLTS activities to ensure the sustainability of the CLTS approach. In order to achieve effective control of STH, deeper collaboration between the WASH and STH sectors are recommended where partners can work together in the area of monitoring and evaluation that may include improved parasitological and nutritional status in high-risk groups, as well as sustainable behavior change as outcome indicators.