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Transmitted Helminth Infections in Chinese Schoolchildren Impact of a video-based health education intervention on soil- transmitted helminth infections in Chinese schoolchildren Franziska Andrea Bieri MSc, BSc A thesis submitted for the degree of Doctor of Philosophy at The University of Queensland in 2013 School of Population Health Abstract Worldwide, more than 2 billion people are infected with soil-transmitted helminths (STH), commonly known as intestinal worms. The STH are a group of parasitic nematodes which include roundworms (Ascaris lumbricoides), whipworms (Trichuris trichiura) and hookworms (Necator americanus and Ancylostoma duodenale). Diseases caused by the STH belong to the group of Neglected Tropical Diseases, comprising 17 infections currently targeted for prevention and research by the World Health Organization, the United Nations Development Program and the World Bank. STH are intimately connected with rural poverty, inadequate sanitation and waste disposal, lack of clean water and poor hygiene, as well as limited access to health care and preventive measures such as health education. Even though STH rarely cause death, they impact significantly on public health and cause severe disability in the world’s poorest countries. The worldwide burden of STH has been estimated to be as high as 39 million disability-adjusted life years (DALYs), with almost half of the global disease burden due to these worm infections afflicting children aged 5-14 years. Nevertheless, STH remain largely neglected by the medical and international community. In China, STH still impact substantially on public health with an estimated 129 million infected people and children aged 5-14 years having the highest rates of infection. Major endemic foci are observed in the central, western and southern provinces. To date, mass drug administration (MDA), aimed at treating morbidity, has been the cornerstone of STH control and is promoted by the World Health Organization. However, long- term health benefits of mass drug administration are limited due to rapid reinfection and there is growing concern about the development of parasite resistance to albendazole and other anti-STH drugs as a result of continued treatment pressure. Therefore, interventions that prevent STH reinfection, such as improvements in hygiene achieved through health education, are required to augment chemotherapy as part of an integrated approach, whereby chemotherapy reduces morbidity and prevalence, and preventive interventions (e.g. health education) prevent reinfection, thus reducing incidence. This will limit the number of treatment cycles required for effective control and subsequently reduce the treatment pressure, as well as creating a more sustainable long-term approach to control. The major objective of the thesis was to determine whether a video-based education package, targeting STH prevention at school widens the students' knowledge and changes their behaviour, i resulting in fewer STH infections. Further, we systematically reviewed school-based video interventions targeting infectious diseases and formulated informed guidelines for the evaluation of future video-based studies within the school setting. In a cluster randomized trial (N=1718 schoolchildren) in rural Hunan Province, China, we tested the efficacy of the educational control tool, based on an educational video, which was professionally developed during the course of the thesis. The results showed that an educational package based on the cartoon video ‘The Magic Glasses’ was highly effective in increasing knowledge, improving hand washing behaviour and preventing STH incidence. There was a 50% efficacy in preventing STH infections (P<0.0001) and a 90% increase in knowledge scores between the intervention and control groups (P<0.0001). The proportion of students washing hands after using the toilet increased by a factor of two in the intervention group (P<0.02). The 50% efficacy in preventing STH infection is unprecedented for health education targeting STH. This was due to an increase in knowledge and improved hygiene practice and establishes proof of principle that the video-based health educational intervention widens student awareness and changes behaviour, resulting in fewer STH infections. A clear correlation between knowledge, attitude and practice (KAP) and STH incidence was evident as, across the entire study population, uninfected students scored, on average, 9.88 points higher in the KAP questionnaire than infected students. A correlation was also observed between KAP and hand washing in both intervention and control groups. Notably, therefore, this study provides valid and highly significant quantitative evidence in the form of a rigorously planned, implemented and reported RCT and contributes substantially to the evidence base assessing the impact of video-based public health interventions. The effective video-based health educational tool we have developed suitably complements the approach advocated by WHO and other agencies. Furthermore, it can readily be incorporated into current ongoing STH de-worming programs, such as the Schistosomiasis Control Initiative (SCI) activities in sub-Saharan Africa and the Chinese national STH control program, launched in 2006 by the Chinese Ministry of Health. Further studies are now needed to assess the cost-effectiveness and the adaptability of the educational package to different cultural settings and as part of a multi-component integrated package for STH control. If such an approach proves effective, then its use can be up-scaled to national Chinese and international levels. Ideally, the educational package would be integrated into the health education curriculum at schools in STH-endemic areas. Such an integrated approach, ii combining chemotherapy, sanitation and health education, has the potential to contribute to a considerable reduction, if not elimination of this most common and insidious group of intestinal parasites globally. Photograph title page: Schoolchildren watching the educational cartoon ‘The Magic Glasses’, Linxiang City District, Hunan Province, China. (Photograph: Bieri 2010) iii Declaration by author This thesis is composed of my original work, and contains no material previously published or written by another person except where due reference has been made in the text. I have clearly stated the contribution by others to jointly-authored works that I have included in my thesis. I have clearly stated the contribution of others to my thesis as a whole, including statistical assistance, survey design, data analysis, significant technical procedures, professional editorial advice, and any other original research work used or reported in my thesis. The content of my thesis is the result of work I have carried out since the commencement of my research higher degree candidature and does not include a substantial part of work that has been submitted to qualify for the award of any other degree or diploma in any university or other tertiary institution. I have clearly stated which parts of my thesis, if any, have been submitted to qualify for another award. I acknowledge that an electronic copy of my thesis must be lodged with the University Library and, subject to the General Award Rules of The University of Queensland, immediately made available for research and study in accordance with the Copyright Act 1968. I acknowledge that copyright of all material contained in my thesis resides with the copyright holder(s) of that material. Where appropriate I have obtained copyright permission from the copyright holder to reproduce material in this thesis. iv Publications during candidature . Bieri FA, Gray DJ, Raso G, Li YS, McManus DP. A systematic review of preventive health educational videos targeting infectious diseases in schoolchildren. The American Journal of Tropical Medicine and Hygiene 2012;87:972-8. Incorporated as Chapter 3. Bieri FA, Bedford A, Gray DJ, Williams GM, Li YS, Yuan LP, Li RS, He YK, Raso G, Guo FY, Li SM, McManus DP. Development of an educational video for the prevention of soil-transmitted helminth infections in Chinese schoolchildren. Submitted to PLoS Neglected Tropical Diseases. Incorporated as Chapter 5. Bieri FA, Gray DJ, Williams GM, Raso G, Li YS, Yuan LP, He YK, Li RS, Guo FY, Li SM, McManus DP. Health-education package to prevent worm infections in Chinese schoolchildren. New England Journal of Medicine 2013;368:1603-12. Incorporated as Chapter 6. Yi P, Li SM, Bieri FA, Yuan LP, Zhao ZY, He YK, Liu ZC, Zhou J, He HB. Selection of government instruments in schistosomiasis control services. Zhongguo xue xi chong bing fang zhi za zhi 2011;23:333-6. Chin J Schisto Control 2011, Vol. 23, No. 3. Yi P, Yuan LP, Wang ZH, He YK, Jing QS, Zhou J, Wang HB, Li SM, Bieri FA. Retrospective survey of 184 patients infected with Schistosoma haematobium from African countries. Zhongguo xue xi chong bing fang zhi za zhi 2011;23:441-2. Chin J Schisto Control 2011, Vol. 23, No. 4. v Conference presentations . Bieri FA, Gray DJ, Williams GM, Li YS, Yuan LP, Li RS, Guo FY, Li SM, McManus DP. Health education works! Video-based health education prevents soil-transmitted helminth (STH) infections in Chinese schoolchildren. In: XVIII International Congress for Tropical Medicine and Malaria, Rio de Janeiro, Brazil, September 2012. Bieri FA, Gray DJ, Williams GM, Li YS, Yuan LP, Li RS, Guo FY, Li SM, McManus DP. Video-based health education prevents soil-transmitted helminth (STH) infections in Chinese schoolchildren. In: First Forum on Surveillance Response System Leading to Tropical
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