Introduction

Soil-transmitted helminth (STH) infections present significant public health challenges, particularly among children in low- and middle-income countries, including Lao People’s Democratic Republic (Lao PDR). According to the World Health Organization (WHO), approximately 24% of the global population, including over 568 million primary school pupils, are affected by STH infections.¹ Vulnerable populations primarily reside in tropical and subtropical regions, with the highest burden concentrated in resource-limited countries across Asia, Africa, and the Americas.¹ In Lao PDR, a developing country with a tropical monsoon climate, children under 10 years old are disproportionately at risk of STH infections due to inadequate access to sanitation facilities, clean water, and routine deworming programs.²

Previous studies have highlighted the alarming prevalence of STH in Laos, with hookworm infection being the most common, affecting 43.6% of the population.³ According to the Lao Department of Preventive Medicine, more than 50% of primary school pupils were infected with STHs, posing significant health risks.⁴ As of 2022, an estimated 1.72 million pupils aged 6 to 11 years old were identified as being at high risk for worm infections, which can lead to malnutrition and delayed physical and cognitive development.¹

In Laos, particularly in Udomxay province, where the burden of STH is particularly pronounced, the primary strategy for controlling STH infections involves periodic mass drug administration (MDA) of antihelminthics to at-risk pupils.² While MDA has proven effective in reducing infection rates, it does not address reinfection risks, necessitating complementary interventions to ensure long-term prevention. Health education, as an affordable and practical measure, is a critical component of STH prevention strategies. By promoting awareness of sanitation and hygiene practices, health education can significantly reduce the behavioral factors that facilitate STH transmission and reinfection within school environments.²

To address these challenges, we conducted a health education intervention study accompanied by pre- and post-intervention surveys. The study targeted grades 4 and 5 pupils from Bankhat and Namgan primary schools in Xay District, Udomxay Province, Laos. The baseline survey revealed that pupils had limited knowledge and poor practices regarding STH prevention, with only 38.3% demonstrating adequate knowledge and only 34.7% exhibiting appropriate practices. This paper evaluates the effectiveness of a 1 year health education intervention in improving the knowledge and practices of school pupils in preventing STH infections. By assessing these outcomes, the study provides insights into the potential of school-based health education programs as a sustainable approach to reducing the burden of STH in resource-limited settings such as Xay District, Udomxay Province, Laos.

Methods

Study Design: This study employed a repeat cross-sectional design without a control group to evaluate the effectiveness of a health education intervention. Surveys were conducted at 2-time points: pre-intervention (baseline in 2021) and post-intervention (2023). A 2-stage sampling approach selected 363 pupils from Bankhat and Namgan primary schools in Xay District, Udomxay Province, Laos.

Key messages for soil-transmitted helminth prevention

The intervention emphasized practical hygiene messages in Laotian, including washing hands before meals, using soap after toilet use or playing with soil, wearing appropriate footwear, and maintaining food safety through proper washing and storage. Pupils were encouraged to adopt these behaviors as routine practices to reduce STH transmission risk.

Study setting: This study was conducted at Bankhat and Namgan primary schools, located in Xay District, Udomxay Province, Laos (Figure 1). Baseline and follow-up data were collected using a pre-tested interviewer-self-administered questionnaire designed to capture demographic information and assess pupils’ knowledge and practices related to STH prevention.

Figure 1.

The study area: Bankhat and Namngan primary schools, Xay district, Lao PDR.

Sample size and selection of participating pupils: Sample size calculations were based on baseline prevalence estimates of poor knowledge and practices in STH prevention among pupils. All 363 pupils who consented to participate in the 1 year follow-up were included in the study.

Data collection and analysis

Baseline and follow-up data were collected using the same validated questionnaire. The collected data were double-checked for completeness and accuracy before and after entry into SPSS (Version 20.0) for analysis. Key outcome variables included knowledge and practice scores, which were compared pre- and post-intervention using the McNemar test to assess changes. Statistical significance was determined at P < .05. A pairing or matching subject approach was adopted to control for potential confounders and measure paired outcomes. Missing data were addressed using robust measures to ensure data reliability. Enumerators reviewed survey responses on-site, and a complete-case analysis was performed for the final dataset. For minor demographic variables with missing data, mean or mode imputation was applied. Sensitivity analyses were conducted to evaluate the potential impact of missing data on the findings.

Results

General characteristics

In total, 363 school pupils aged 7 to 11 years old participated at the baseline and post-intervention surveys. The characteristics of the school pupils are summarized in Table 1.

Table 1.

Characteristics of the studied primary school pupils.

Table 1 shows the characteristics of 363 primary school pupils: 56.5% were males and 43.5% were females; 47.4% of fourth grade and 52.6% of fifth grade pupils. Large family size (>2 members) and poverty were predominant, with about 56.5% and 51.2%, respectively. Almost all of the pupils’ houses (98.9%) did not have access to piped water supply, so they used well water instead.

The effectiveness of health education intervention to improve knowledge of soil-transmitted helminths prevention

The effectiveness of the health education intervention to improve knowledge about STH infections for school pupils is summarized in Table 2.

Table 2.

Effectiveness in improving knowledge about STH, agents causing STH and mode of transmissions.

The results in Table 2 demonstrate a significant improvement in pupils’ knowledge regarding STH, the agents causing STH, and their modes of transmission following the health education intervention. The percentage of pupils who were aware of STH increased dramatically from 39.4% at baseline to 80% at endline (P < .001). Awareness of parasites as causative agents increased from 12.1% at baseline to 80.3% post-intervention, showing a substantial improvement in understanding the role of parasites in STH infections (P < .001). Knowledge of STH transmission through ingestion increased from 27% at baseline to 94.3% at endline (P < .001). Awareness of STH transmission through skin penetration improved from 0.6% to 97.2% (P < .001). The understanding of both routes of transmission rose from 2.5% to 93.5% (P < .001). Overall, the intervention was highly effective in increasing pupils’ understanding of STH, its causative agents, and transmission pathways. These significant improvements suggest that the educational program successfully enhanced awareness, equipping pupils with essential knowledge to prevent STH infections.

The findings in Table 3 illustrate significant improvements in pupils’ knowledge of methods to prevent STH infection following the health education intervention. Awareness of the importance of taking deworming pills increased substantially, with 96.4% of pupils recognizing its importance at endline, compared to only 8.8% at baseline. Understanding of environmental sanitation as a preventive measure rose from 12.1% to 93.4%, highlighting a marked enhancement in pupils’ comprehension of the role of a clean environment in reducing STH risks.

Table 3.

Effectiveness in improving knowledge on how to prevent soil-transmitted helminth infection.

Knowledge about the necessity of thorough handwashing improved dramatically, increasing from 44.4% at baseline to 98.0% post-intervention. Awareness of the importance of using toilets for defecation grew from 39.4% to 92.3%. Similarly, recognition of the need to drink clean, boiled water as a preventive measure rose from 37.2% to 96.1%. Knowledge of wearing footwear to minimize STH transmission risk improved from 26.4% at baseline to 82.0% at endline.

These findings underscore the effectiveness of the health education intervention in equipping pupils with critical knowledge to prevent STH infections. By significantly enhancing awareness of various preventive practices, the intervention has empowered pupils with the tools to avoid common sources of infection, which is crucial in high-risk settings. This enhanced knowledge is likely to result in improved health outcomes and contribute to the reduction of STH transmission rates within the community.

The findings presented in Table 4 reveal a substantial improvement in pupils’ overall knowledge scores regarding STH infections following the health education intervention. At baseline, only 38.3% of pupils achieved a “good-knowledge” score. However, this proportion increased significantly to 96.4% in the post-intervention assessment, reflecting a marked shift in pupils’s understanding from limited to comprehensive knowledge of STH infections and their prevention. This substantial increase in knowledge scores suggests the effectiveness of the intervention in conveying critical information about STH infections. By providing pupils with a robust knowledge base, the intervention likely establishes a foundation for sustained behavioral changes that help mitigate STH transmission risks. These findings highlight the value of structured health education programs in improving awareness and understanding, particularly among high-risk populations. Furthermore, they underscore the potential for similar interventions to deliver public health improvements in other communities affected by STH infections.

Table 4.

Effectiveness of improving knowledge score of soil-transmitted helminth infection.

Effective health education interventions to improve practices of preventing soil-transmitted helminth infections

The effectiveness of interventions to improve the practice of preventing STH infections for secondary school pupils is summarized in Table 5.

Table 5.

Improving practices of preventing of soil-transmitted helminths infections.

The findings in Table 5 demonstrate substantial improvements in pupils’ practices for preventing STH infections following the health education intervention. Key behavioral changes include a substantial increase in the proportion of pupils practising proper hygiene and sanitation behaviors. The percentage of pupils who washed their hands before eating rose sharply from 17.6% at baseline to 93.0% post-intervention, while handwashing after toilet use increased from 12.4% to 94.7%, demonstrating a remarkable improvement in hygiene practices. Additionally, the proportion of pupils who regularly clipped their nails grew from 12.4% at baseline to 90.9% at endline, addressing a common route for infection. The use of toilets for defecation increased significationly from 11.3% at baseline to 92.5% at endline, showing a notable shift toward proper sanitation practices. Regular use of footwear, a critical measure for preventing direct contact with contaminated soil, rose from 12.4% to 87.4%. Furthermore, awareness of avoiding uncooked food, a key risk factor for STH transmission, improved from 39.1% at baseline to 95.5%.

The findings presented in Table 6 show a significant improvement in pupils’ overall practice scores for preventing STH infections following the health education intervention. At baseline, only 34.7% of pupils achieved a “good-practice” score, indicating adequate preventive behaviors. However, by the end of the intervention, this figure rose markedly to 91.1%, demonstrating a substantial enhancement in pupils’ adoption of protective practices. This notable improvement in practice scores highlights the effectiveness of the health education intervention in fostering behaviors that reduce STH transmission risks. By transitioning a majority of pupils from “poor practice” to “good practice” levels, the intervention addressed critical gaps in hygiene and sanitation habits, such as inadequate handwashing, lack of footwear, and improper sanitation practices. These findings suggest that the intervention has the potential to contribute significantly to reducing infection risks and promoting sustained health benefits among school-aged children.

Table 6.

Effectiveness of improving the practice score of prevention of soil-transmitted helminths infection.

Discussion

This study demonstrates the effectiveness of a health education intervention in significantly improving the knowledge and practices of primary school pupils regarding STH prevention in Xay District, Udomxay Province, Laos. Overall awareness of STH infections increased markedly, the proportion of pupils with a “good-knowledge” score rose from 38.3% to 96.4%, while the percentage of pupils achieving a “good-practice” score increased from 34.7% to 91.1%. These findings confirm the substantial impact of the intervention in transforming pupils’ understanding and adoption of protective behaviors, consistent with prior research emphasizing the role of health education in promoting effective STH prevention strategies.⁵

While the intervention successfully improved knowledge and practices, underlying structural challenges such as inadequate sanitation facilities and limited access to clean water remain critical barriers. Evidence from similar studies highlights that integrating water, sanitation, and hygiene (WASH) education into community-based approaches yields stronger outcomes compared to school-based efforts alone.⁴ For instance, community-based sanitation programs in India⁶ and Mali⁷ demonstrated significant behavioral changes due to broader engagement beyond the school environment. Conversely, school-based health education interventions in Malaysia⁵ and other low- and middle-income countries⁸ have proven to be highly effective in empowering pupils with the necessary knowledge and skills for STH prevention, aligning with the findings of this study. The results also support the integration of periodic deworming programs with sustained hygiene education, as recommended by studies in the Peruvian Amazon⁹ and other endemic regions. By embedding knowledge and practices of preventing STH infections early, this intervention not only enhances immediate health outcomes but also lays the groundwork for sustained behavioral change, reducing long-term STH transmission risks.

A significant improvement in pupils’ knowledge and practical skills after the intervention was observed in this study and this might be due to health education before the follow-up study. A number of studies have reported the effectiveness of health education to improve pupils’ knowledge and practical skills especially when done annually.^5,9,10 Moreover, significant improvements were also reported with other variables (eg, STH by contaminated hands and walking barefooted, and prevention by wearing shoes when outside the house and washing hands before eating). These findings were in agreement with previous studies elsewhere.^5,9,11,12 Several publications have demonstrated a significant impact in increasing the knowledge and practice among their intervention groups.^5,11 For instance, the rate of hand washing increased from 46.0% to 98.9% among the intervention group whilst remaining unchanged in the control group (from 54.0% to 54.2%). Similarly, almost 5 times as many intervention children (93.7% vs 17.6%) reported washing their hands after defecation.

The increase in overall knowledge score regarding STH infections following the health education intervention is crucial because well-informed pupils are more likely to adopt and sustain preventive behaviors, which can directly reduce STH infection rates.¹³ The results highlight the importance of targeted, age-appropriate health education in equipping childrenwith the necessary knowledge to protect themselves from infections. The intervention also supports the potential for long-term health benefits and reinforces positive health behaviors. Such findings suggest that scaling up similar educational programs could be highly beneficial in other high-risk areas. Moreover, incorporating these programs into national health and education policies could systematically address STH-related public health challenges, especially in communities with limited sanitation infrastructure.

The present study shows that the rates of hand washing before eating and after defecation, wearing shoes when outside and hand washing with soap were almost 4 times among the pupils at endline compared to the rates among the pupils at baseline. These results highlight the effectiveness of structured health education programs in promoting behavior change and reinforcing positive hygiene practices among young students. Moreover, the observed behavioral changes align with previous studies emphasizing the role of school-based interventions in reducing the prevalence of STH infections.⁹ For instance, a study in Peru found that a school-based health hygiene education intervention was effective in increasing STH knowledge and reducing Ascaris lumbricoides infection. Similarly, a systematic review and meta-analysis highlighted the impact of community-based interventions, including health education, in preventing and controlling STHs.¹⁴ Furthermore, our findings showed that overall the knowledge and practices of the school pupils were significantly improved upon 1 year intervention (96.4% good knowledge vs 38.3% at the baseline) and (91.1% good practice vs 34.7% at the baseline). This was imperative to ensure an effective contribution of the intervention when it came to implementing follow up STH prevention activities with the school pupils and the teachers. One remarkable finding in this study was the apparent well of the impact of health education in improving pupils’ knowledge and practical skills in the preventing of STHs. These results indicate that the health education intervention was highly effective in transforming pupils’ hygiene and sanitation practices. The improved practices reflect the intervention’s success in promoting habits that directly reduce the risk of STH infections. This change in behavior is likely to contribute to decreased infection rates and improved overall health among pupils. When implemented in high-risk communities, such interventions not only improve individual health outcomes but can also reduce the overall transmission of STH infections within the community. The success observed here suggests that similar health education interventions could be replicated in other regions to support widespread, long-term improvements in hygiene and disease prevention practices.

As some other studies elsewhere^9,12 have reported an appreciable increase in pupils’ knowledge and practical skills in preventing STHs. Although the study participants were willing and adherent to some of the health education protocols at intervention, it was observed that ignorance of the school pupils was a major factor hindering the sustainability of health education protocols, and most of the school pupils complained that before the intervention, participants did not have enough knowledge and practice to do all of the items required for health education strategies. In addition, the lack of toilet facilities and potable water in the schools of Xay District encouraged open-air defecation, which was a verifiable source of reinfection.

This study underscores the importance of a multi-faceted approach that integrates health education, infrastructure development, and community engagement to achieve comprehensive control of STH infections. While the intervention significantly influenced behavior change, addressing structural barriers related to sanitation and water access is crucial for long-term success. Expanding these interventions to involve the broader community could amplify their impact beyond the school setting, enhancing their overall effectiveness.

Limitations: This study was school-based and thus limited to pupils currently attending school, potentially excluding out-of-school children who may face higher STH infection risks. Additionally, the absence of a control group restricts the ability to attribute observed improvements solely to the intervention, as external factors may have contributed. The study’s focus on Bankhat and Namgan primary schools in Xay District limits the generalizability of findings to other regions of Laos PDR. Moreover, the long-term sustainability of the observed improvements remains unaddressed. Future research should include longitudinal assessments to evaluate the persistence of knowledge and practice changes and explore the broader impact of combined educational and structural interventions.

Conclusion

The study highlights the importance of health education in improving pupils’ knowledge and practical skills for the prevention of STH infections among primary school pupils in Xay District, Udomxay Province, Laos. The intervention resulted in a substantial improvement, with the proportion of pupils demonstrating good knowledge and practice scores increasing from 38.3% and 34.7% at baseline to 96.4% and 91.1%, respectively, post-intervention. These findings highlight the effectiveness of targeted educational programs in equipping children with the necessary knowledge and behaviors to reduce STH transmission risks. However, achieving sustainable control and elimination of STH infections in Laos requires a multifaceted approach that combines health education with community engagement and infrastructural improvements.

Recommendations

To build on these findings, future interventions should adopt a comprehensive, integrated approach that expands the scope of health education beyond the school setting. Community-based programs should be implemented to extend the reach of hygiene promotion and foster widespread behavioral change. Investments in infrastructure are equally essential. Efforts must focus on improving access to clean water and sanitation facilities, as these structural improvements are fundamental to reducing STH transmission. Governments, non-governmental organizations, and stakeholders should prioritize creating environments that support sustained hygiene practices and minimize reinfection risks. Additionally, continuous monitoring and evaluation of interventions are crucial for assessing their long-term impact on STH infection rates. Longitudinal studies should be conducted to track progress, identify challenges, and refine strategies over time. National health policies in Laos should prioritize comprehensive STH prevention strategies that integrate health education, improved sanitation, and community engagement. Such coordinated efforts are vital for achieving lasting public health improvements in Xay District, Udomxay Province, Laos and in other communities vulnerable to STH infections.