Teaching Strategies to Enhance Knowledge and Understanding of Opisthorchis viverrini and Cholangiocarcinoma in Thailand: Lessons for Asian Countries

Although Opisthorchis viverrini (OV) is a neglected tropical disease, the International Agency for Research on Cancer (IARC) listed it as a human carcinogen 30 years ago. Cholangiocarcinoma (CCA) is the ultimate pathology outcome. However, it remains a significant public health problem in the Greater Mekong Subregion and Asia. Its widespread impact on human health requires urgent action using various strategies. This study aimed to investigate and prioritize the need for developing teaching and learning management of OV and CCA among primary school students in Thailand endemic areas. The samples consisted of 36 Grade 6 students. This study was conducted by using a needs questionnaire. Data were analyzed using Mean and Standard Deviation. The needs were prioritized using the Modified Priority Needs Index (PNI modified). The findings revealed a moderate overall need for teaching and learning management development. The area with the highest need was learning activity organization (PNI = 0.410), followed by audiovisual equipment (PNI = 0.276) and buildings (PNI = 0.265). The teaching content the students needed most included CCA prevention, risk factors, and disease symptoms (58.33%). Based on the findings, it is suggested that teachers design various learning activities and emphasize hands-on activities for students. Additionally, administrators should allocate budgets to improve buildings and audiovisual equipment, and relevant organizations should establish policies to promote learning on these issues in educational institutions. Essential lessons from this study can provide a starting point for executives and public health personnel worldwide to apply to develop educational strategies for cancer education and cancer prevention and control.

Cancer Education-Based Learning Management to Enhance Health Literacy for Cholangiocarcinoma Prevention Among Primary School Students in Endemic Areas of Thailand: The Muk-KAMSComD Model

Effective cancer prevention requires early interventions to enhance health literacy, particularly for Opisthorchis viverrini (OV) and cholangiocarcinoma (CCA) in the Greater Mekong Subregion. This study developed and evaluated the Muk-KAMSComD Model, a structured learning management approach, to improve health literacy and preventive behaviors among primary school students in Mukdahan Province, a high-risk area in Thailand. A four-step research and development (R&D) framework was implemented: (1) situation and needs assessment, (2) model development, (3) implementation, and (4) refinement and presentation. Thirty-six Grade 6 students were selected through multi-stage sampling, and a one-group pretest-posttest design assessed health literacy using validated questionnaires. The 12-week intervention integrated the HALO Model (Healthy School, Active Learning, Lesson Study, and Open Class) with six key health literacy skills. Data were analyzed using qualitative content analysis, descriptive statistics, and paired t-tests. The Muk-KAMSComD Model consists of Knowledge provision, Awareness and belief creation, Motivation enhancement, Self-management practice, Communication, and Decision-making and forwarding. Post-intervention, students significantly improved (p < 0.001) in knowledge, communication, self-management, media literacy, information access, and decision-making skills. Information access showed the highest improvement, while self-management remained the lowest. The model was refined to strengthen parental engagement and instructional materials for enhanced effectiveness. The Muk-KAMSComD Model effectively strengthens health literacy and preventive behaviors for OV and CCA among primary school students. Its integration into school curricula and public health programs could contribute to sustainable CCA prevention in endemic regions.

Impact of self-efficacy-based health education programs on behavior modification for Opisthorchis viverrini and cholangiocarcinoma prevention in Thailand: A systematic review and meta-analysis

Opisthorchis viverrini (OV) infection, which can progress to cholangiocarcinoma (CCA), poses a critical public health challenge. While numerous studies have investigated behavior modification programs aimed at preventing OV and CCA, the effectiveness of these interventions remains inconclusive. This systematic review and meta-analysis sought to synthesize evidence on the efficacy of behavior modification programs, particularly those based on self-efficacy, in preventing OV and CCA. We reviewed experimental and quasi-experimental studies, comprising 2-group comparisons or 1-group pretest-posttest designs, that evaluated health education interventions focused on behavior modification for OV and CCA prevention. Relevant literatures was systematically retrieved from the PubMed, Google Scholar, ThaiJo, and ThaiLis databases. Of 702 identified studies, 13 met the systematic review and meta-analysis inclusion criteria. The analysis assessed the quality of the studies, extracted data, and evaluated the risk of bias. Standardized mean differences were calculated to determine the impact of self-efficacy- based programs on knowledge, self-efficacy, and behavior modification. The results indicated significant post-intervention improvements in all outcomes (P<0.001) despite high heterogeneity in knowledge (I²=76%), self-efficacy (I²=77%), and behavior modification (I²=93%). The experimental group demonstrated significantly more significant improvements in knowledge (mean difference=1.52, 95% confidence interval (CI)=1.36-1.68), self-efficacy (mean difference=1.08, 95% CI=0.90-1.26), and behavior modification (mean difference=1.78, 95% CI=1.63-1.92) compared to the comparison group, with I² values of 74%, 84%, and 92%, respectively. In conclusion, health education programs grounded in self-efficacy principles effectively enhance knowledge, selfefficacy, and behavior modification to prevent OV and CCA. These findings suggest that self-efficacy-based behavior modification programs may also apply to the prevention of other diseases.

Clonorchiasis and opisthorchiasis: epidemiology, transmission, clinical features, morbidity, diagnosis, treatment, and control

Clonorchis sinensis, Opisthorchis viverrini, and Opisthorchis felineus are important liver flukes that cause a considerable public health burden in eastern Asia, southeastern Asia, and eastern Europe, respectively. The life cycles are complex, involving humans, animal reservoirs, and two kinds of intermediate hosts. An interplay of biological, cultural, ecological, economic, and social factors drives transmission. Chronic infections are associated with liver and biliary complications, most importantly cholangiocarcinoma. With regard to diagnosis, stool microscopy is widely used in epidemiologic surveys and for individual diagnosis. Immunologic techniques are employed for screening purposes, and molecular techniques facilitate species differentiation in reference laboratories. The mainstay of control is preventive chemotherapy with praziquantel, usually combined with behavioral change through information, education and communication, and environmental control. Tribendimidine, a drug registered in the People's Republic of China for soil-transmitted helminth infections, shows potential against both C. sinensis and O. viverrini and, hence, warrants further clinical development. Novel control approaches include fish vaccine and biological control. Considerable advances have been made using multi-omics which may trigger the development of new interventions. Pressing research needs include mapping the current distribution, disentangling the transmission, accurately estimating the disease burden, and developing new diagnostic and treatment tools, which would aid to optimize control and elimination measures.

Liver Flukes: Clonorchis and Opisthorchis

Clonorchis sinensis, Opisthorchis viverrini and O. felineus are liver flukes of human and animal pathogens occurring across much of Europe and Asia. Nevertheless, they are often underestimated compared to other, better known neglected diseases in spite of the fact that many millions of people are infected and hundreds of millions are at risk. This is possibly because of the chronic nature of the infection and disease and that it takes several decades prior to a life-threatening pathology to develop. Several studies in the past decade have provided more information on the molecular biology of the liver flukes which clearly lead to better understanding of parasite biology, systematics and population genetics. Clonorchiasis and opisthorchiasis are characterized by a chronic infection that induces hepatobiliary inflammation, especially periductal fibrosis, which can be detected by ultrasonography. These chronic inflammations eventually lead to cholangiocarcinoma (CCA), a usually fatal bile duct cancer that develops in some infected individuals. In Thailand alone, opisthorchiasis-associated CCA kills up to 20,000 people every year and is therefore of substantial public health importance. Its socioeconomic impacts on impoverished families and communities are considerable. To reduce hepatobiliary morbidity and CCA, the primary intervention measures focus on control and elimination of the liver fluke. Accurate diagnosis of liver fluke infections in both human and other mammalian, snail and fish intermediate hosts is important for achieving these goals. While the short-term goal of liver fluke control can be achieved by praziquantel chemotherapy, a comprehensive health education package targeting school children is believed to be more beneficial for a long-term goal/solution. It is recommended that transdisciplinary research or multisectoral control approach including one health and/or eco health intervention strategy should be applied to combat the liver flukes and hence contribute to reduction of CCA in endemic areas.

EASL-ILCA Clinical Practice Guidelines on the management of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) develops inside the liver, between bile ductules and the second-order bile ducts. It is the second most frequent primary liver cancer after hepatocellular carcinoma, and its global incidence is increasing. It is associated with an alarming mortality rate owing to its silent presentation (often leading to late diagnosis), highly aggressive nature and resistance to treatment. Early diagnosis, molecular characterisation, accurate staging and personalised multidisciplinary treatments represent current challenges for researchers and physicians. Unfortunately, these challenges are beset by the high heterogeneity of iCCA at the clinical, genomic, epigenetic and molecular levels, very often precluding successful management. Nonetheless, in the last few years, progress has been made in molecular characterisation, surgical management, and targeted therapy. Recent advances together with the awareness that iCCA represents a distinct entity amongst the CCA family, led the ILCA and EASL governing boards to commission international experts to draft dedicated evidence-based guidelines for physicians involved in the diagnostic, prognostic, and therapeutic management of iCCA.

RAW ATTITUDES: Socio-Cultures, Altered Landscapes, and Changing Perceptions of an Underestimated Disease

Raw attitudes relate to the food cultures, eating habits, and behaviours of people in relation to the consumption of raw, partially cooked, and fermented freshwater fish dishes, which puts people at risk of Ophistochis viverrini and other parasitic infections. The chapter reviews raw attitudes within the countries and across the borders of the greater Mekong region, particularly northeast Thailand, Lao PDR, Vietnam, and Cambodia. Rather than treat each nation-state as an isolated epidemiological box, the chapter explores transborder complexity in relation to multiple anthropogenic transformations to the landscapes of the region and developmental impacts upon ecosystems and life cycles. Economic projects such as multiple hydropower dams, irrigation schemes, water-diversions, roads, and aquaculture ponds have significant impacts on FTZ life-cycle dynamics. In addition, many ecological changes are transboundary ones, and there are added complications relating human mobility, altered agrarian landscapes, and significant numbers of migrant workers. The chapter also examines public health programmes and educational interventions which are altering perceptions of O. viverrini and cholangiocarcinoma over time. A key argument is the need for transdisciplinary scientific and social science strategies alongside multi-pronged health interventions, such as 'the CASCAP model'. There exist many unknowns and gaps relating to widespread anthropogenic modifications upon life cycles, upon lifestyles, livelihoods, and human behaviours, which require research projects that span socio-economic, ecological, geographical, and public health dynamics of disease.

Epidemiology and Control of Opisthorchis viverrini Infection: Implications for Cholangiocarcinoma Prevention

It is known that Opisthorchis viverrini (OV) is the most significant risk factor for the development of cholangiocarcinoma (CCA); hence, it is also known as carcinogenic parasite. Effective control and elimination of OV infection should significantly reduce O. viverrini-related CCA. This chapter includes details of the three recently developed innovative tools, namely the Isan cohort database software, an OV-RDT for screening of O. viverrini, and an ultrasound telecommunication system. Past and current control programs, i.e., education, medication, and sanitation were discussed and stressed the need for a comprehensive control program which encompasses primary, secondary, and tertiary patient care programs for confirmation and management of suspected CCA cases. The approach of mathematical modeling for control of OV and CCA was also briefly described. Additionally, we highlighted the current progress toward control of OV and CCA in Thailand and potential for expansion into nearby countries in Southeast Asia.

Public health interventions for preventing re-infection of Opisthorchis viverrini: application of the self-efficacy theory and group process in high-prevalent areas of Thailand

OBJECTIVE

To study the effectiveness of public health interventions in preventing Opisthorchis viverrini (OV) re-infection in high-prevalence areas of Thailand.

METHODS

68 people from Sisaket, the province with the second-highest prevalence in Thailand, who tested positive for OV eggs in faeces and took praziquantel before the start of the study, participated. 34 participants were allocated to the experimental group, which received a 12-week public health intervention based on the self-efficacy theory and group process between July and October 2018. The control group received the usual services. Data were collected using a questionnaire with a reliability of 0.84. Faecal examinations using the formalin-ether concentration technique were conducted before and after the experiment. The re-infection rate was analysed after the experimental 12 weeks and after one year. Descriptive and inferential statistics, including paired t-test and independent t-test, were employed for data analysis.

RESULTS

After the experiment, the mean scores of knowledge, perceived self-efficacy, self-efficacy expectation and OV prevention behaviour of the experimental group were significantly higher than before the experiment and also higher than scores of the control group (P < 0.05).

CONCLUSION

The public health intervention is useful. It educated the experimental group about OV, perceived self-efficacy and self-efficacy expectation in changing behaviour to prevent OV re-infection. As a result, no re-infections were observed after the 12-week intervention nor at the one-year follow-up. Public health benefits will be evident if the results are extended to other high-prevalence areas.

Masculinity and misinformation: Social dynamics of liver fluke infection risk in Thailand

Liver fluke infection through the consumption of raw or undercooked freshwater fish is a major public health problem in the Mekong Region. Despite the extensive efforts of liver fluke health campaigns, Northeast Thailand still reports high human infection prevalence as consumption of raw fish dishes has diminished but not ceased. This study examines the roles of social-cultural factors, particularly the influences of masculinity and misinformation, on liver fluke infection risk. Participant observation, questionnaire surveys and semi-structured interviews were conducted in four villages in Kalasin Province, Thailand, to scrutinize reasons for raw fish consumption, gender differences in raw fish culture, processes of liver fluke information dissemination, and the extent of information mismatch. Our results show that one of the key reasons (76.9%) underlying continued raw fish consumption are deeply embedded cultural practices associated with ways of rural life. About 30% of the participants indicated that they would not avoid eating raw fish, regardless of knowing the health consequences. Gender difference is evident, with 75.6% of males consuming raw fish salad (koi pla), compared to 42.7% of females. Some male participants associate raw meat consumption with virility and strength. Such beliefs underscore the cultural linkage of koi pla consumption with masculinity. Misconceptions of liver fluke life cycle and risk of infection remain, as only 15.3% of the participants correctly selected raw fish as the food source for liver fluke infection while 84.2% misunderstood that other raw foods could lead to infection. The multi-layered and hierarchical structure of public health information dissemination from medical professionals to health officers and village health volunteers to villagers has contributed to information mismatch between different layers. Our study builds on others which call for multi-pronged scientific and social strategies, as well as culturally attuned approaches to public health messaging. The study raises masculinity and misinformation as relevant considerations in disease prevention. Incorporating grounded research and gendered perspectives are part of appreciating the cultural roots of raw fish consumption. Realizing the significant role of village health volunteers in information dissemination and in supplying coherent public health messages is vital for effective health campaigns.

Foodborne zoonotic parasites of the family Opisthorchiidae

Several foodborne zoonotic trematodes of the family Opisthorchiidae have been reported to infect people, specifically two genera, Clonorchis and Opisthorchis. Three species Clonorchis sinensis, Opisthorchis felineus and Opisthorchis viverrini are the most extensivley studied of the Opisthorchiidae. At least 680 million people worldwide are at risk of infection of these liver flukes through the consumption of raw or partially cooked freshwater cyprinid fish. An estimated 45 million people in Europe and Asia are currently infected with these liver flukes. Of these, the 35 million are infected with C. sinensis mainly in China, 10 million with O. viverrini in Southeast Asia, and 1.2 million with O. felineus in Eastern Europe and Russia. These liver flukes have been proven to be causative agents of bile duct cancer or cholangiocarcinoma (CCA). A multidisciplinary program should be implemented involving comprehensive research on molecular genetics, diagnosis, treatment, prevention, as well as educational and control programs should progressively be introduced and applied in endemic regions of O. viverrini, O. felineus and C. sinensis throughout their ranges, hence, opisthorchiasis and clonorchiasis free communities can be realised globally.

Community- Based Approaches to Cancer Prevention in Rural Thailand Based on Experiences of Accredited Health Professionals

This qualitative research aimed to describe important components of community based approaches of cancer prevention from working experiences of accredited health professionals in Thai rural communities.

METHODS

Data were collected from 23 communities with 23 accredited health professionals as key participants using in-depth interview and focus group discussions (FGDs) in each community. Other informants were community leaders, community health volunteers and community people. Content analysis was applied for data analysis.

RESULTS

Community based approaches for cancer prevention from the experiences of accredited health professionals were composed of 2 themes: approaches for community-based cancer prevention and methods for cancer-based prevention in the community. The approaches for community-based cancer prevention was composed of 4 components: 1) primary prevention focusing on health education; 2) secondary prevention include: life style modification, vaccination, advocacy of cancer screening, early detection, and prompt refer; 3) tertiary prevention focusing on primary care, and 4) research collaboration focusing on net working.  Methods for cancer-based prevention in the community were different based on types of cancer.  The 3 factors determined to be associated with community based approaches for cancer prevention were: 1) primary care policy; 2) hometown workplace; and 3) health practice skill.

CONCLUSION

Community based approaches for cancer prevention should concentrate on building a literate community involvement to empower both health care providers and residents. From our evidence, dedicated community associates health professionals have a major role to play.

Liver Flukes: Clonorchis and Opisthorchis

Clonorchis sinensis, Opisthorchis viverrini, and O. felineus are liver flukes of human and animal pathogens occurring across much of Europe and Asia. Nevertheless, they are often underestimated compared to other, better known neglected diseases in spite of the fact that many millions of people are infected and hundreds of millions are at risk. This is possibly because of the chronic nature of the infection and disease and that it takes several decades prior to a life-threatening pathology to develop. Several studies in the past decade have provided more information on the molecular biology of the liver flukes which clearly lead to better understanding of parasite biology, systematics, and population genetics. Clonorchiasis and opisthorchiasis are characterized by a chronic infection that induces hepatobiliary inflammation, especially periductal fibrosis, which can be detected by ultrasonography. These chronic inflammations eventually lead to cholangiocarcinoma (CCA), a usually fatal bile duct cancer that develops in some infected individuals. In Thailand alone, opisthorchiasis-associated CCA kills up to 20,000 people every year and is therefore of substantial public health importance. Its socioeconomic impacts on impoverished families and communities are considerable. To reduce hepatobiliary morbidity and CCA, the primary intervention measures focus on control and elimination of the liver fluke. Accurate diagnosis of liver fluke infections in both human and other mammalian, snail and fish intermediate hosts, are important for achieving these goals. While the short-term goal of liver fluke control can be achieved by praziquantel chemotherapy, a comprehensive health education package targeting school children is believed to be more beneficial for a long-term goal/solution. It is recommended that a transdisciplinary research or multisectoral control approach including one health and/or eco health intervention strategy should be applied to combat the liver flukes, and hence contribute to reduction of cholangiocarcinoma in endemic areas.

Current Perspectives on Opisthorchiasis Control and Cholangiocarcinoma Detection in Southeast Asia

Similar to bile duct cancer or cholangiocarcinoma (CCA) in the western world, opisthorchiasis-associated CCA in Southeast Asia is an aggressive cancer with high mortality rates. It is known to cause a significant health burden in the opisthorchiasis region in Thailand and possibly throughout mainland Southeast. To reduce this health burden, a comprehensive prevention and control program for opisthorchiasis, as well as CCA, is required. In this review, our aim is to provide a brief update of the current situation regarding the natural history of opisthorchiasis and health burden of CCA in Southeast Asia. A comprehensive approach to tackling these issues being implemented in Thailand under the “Cholangiocarcinoma Screening and Care Program” is described. This comprehensive program consists of a three stage prevention and patient care program. The primary prevention component involves opisthorchiasis screening using a new and sensitive urine assay. The secondary prevention component involves screening for CCA and periductal fibrosis, with suspected CCA patients following the protocol for confirmation and appropriate treatment. Due to the eco-epidemiology of opisthorchiasis-induced CCA, the anticipated impacts and outcomes of the program include short-, medium-, and the long-term goals for the reduction of CCA incidence. To achieve long-term sustainable impacts, concerted efforts to raise social awareness and participating action by general public, non-government organizations, and government agencies are necessary. The strategic plans developed for this program can be expanded for use in other endemic areas as well as being a model for use in other chronic diseases.

The Socioeconomic Burden of Cholangiocarcinoma Associated With Opisthorchis viverrini Sensu Lato Infection in Northeast Thailand: A Preliminary Analysis

The northeast of Thailand, which is the poorest region of the country, has the highest incidence of cholangiocarcinoma (CCA) worldwide. This is associated with infection with the liver fluke Opisthorchis viverrini. Although an estimated 20,000 people die every year of this disease, the socioeconomic impact of this mortality on the victims' family and the community in which he or she lived remains unknown. Here, we provide background information on the socioeconomic groups most effected by CCA and provide a qualitative estimate of the likely financial burden on the family and community. Most victims of CCA are small-scale farmers. Mortality occurs most commonly in males between the ages of 40 and 65, having either children or grandchildren to support. Costs can be divided between premortality with the family paying for transport and accommodation to the hospital, as well as costs not covered by the Thai Universal Health Coverage scheme. The main costs, however, are likely to be postmortem with loss of income and potentially the loss of a major contributor to farm work. What is urgently required is a quantitative estimate of the costs of CCA and long-term studies of the families and communities affected to determine where and how the burden of CCA falls.

Taxonomy, Ecology and Population Genetics of Opisthorchis viverrini and Its Intermediate Hosts

There have been considerable advances in our understanding of the systematics and ecology of Opisthorchis viverrini; however, this new knowledge has not only clarified but also complicated the situation. We now know that what was once considered to be a single species is, in fact, a species complex, with the individual species being confined to specific wetland areas. There is also a strong genetic association between the members of the O. viverrini species complex and their Bithynia snail intermediate hosts. Although this does not negate data collected before the recognition of this situation, it does lead to the caveat that regional and temporal variations in data collected may be related to the species examined. The advances in ecology have generally been spatially limited and have led, in part, to contradictory results that may well be related to nonrecognition of the species studied. It may also be related to natural temporal and spatial variation related, for example, to habitat characteristics. To understand the variation present, it will be necessary to conduct long-term (several years at least) sampling projects after defining the genetic characteristics of O. viverrini sensu lato and its Bithynia snail intermediate hosts.