Porcine cysticercosis (Taenia solium and Taenia asiatica): mapping occurrence and areas potentially at risk in East and Southeast Asia

The current status of neglected tropical diseases in Japan: A scoping review

Little attention has been paid to neglected tropical diseases (NTDs) in high-income countries and no literature provides an overview of NTDs in Japan. This scoping review aims to synthesize the latest evidence and information to understand epidemiology of and public health response to NTDs in Japan. Using three academic databases, we retrieved articles that mentioned NTDs in Japan, written in English or Japanese, and published between 2010 and 2020. Websites of key public health institutions and medical societies were also explored. From these sources of information, we extracted data that were relevant to answering our research questions. Our findings revealed the transmission of alveolar echinococcosis, Buruli ulcer, Chagas disease, dengue, foodborne trematodiases, mycetoma, scabies, and soil-transmitted helminthiasis as well as occurrence of snakebites within Japan. Other NTDs, such as chikungunya, cystic echinococcosis, cysticercosis, leishmaniasis, leprosy, lymphatic filariasis, rabies, and schistosomiasis, have been imported into the country. Government agencies tend to organize surveillance and control programs only for the NTDs targeted by the Infectious Disease Control Law, namely, echinococcosis, rabies, dengue, and chikungunya. At least one laboratory offers diagnostic testing for each NTD except for dracunculiasis, human African trypanosomiasis, onchocerciasis, and yaws. No medicine is approved for treatment of Chagas disease and fascioliasis and only off-label use drugs are available for cysticercosis, opisthorchiasis, human African trypanosomiasis, onchocerciasis, schistosomiasis, and yaws. Based on these findings, we developed disease-specific recommendations. In addition, three policy issues are discussed, such as lack of legal frameworks to organize responses to some NTDs, overreliance on researchers to procure some NTD products, and unaffordability of unapproved NTD medicines. Japan should recognize the presence of NTDs within the country and need to address them as a national effort. The implications of our findings extend beyond Japan, emphasizing the need to study, recognize, and address NTDs even in high-income countries.

Risk mapping for Taenia solium: Applying multicriteria decision analysis in Lao PDR

OBJECTIVES

Taenia solium is ranked the most significant global foodborne parasite and the leading cause of epilepsy in low and middle-income countries. Diagnostic challenges have hampered disease control efforts to date and WHO has called for the development of risk mapping tools to assist endemic countries. This study describes the application of multicriteria decision analysis to map the risk of T. solium in Lao PDR and acts as a case study for other endemic countries.

METHODS

Multicriteria decision analysis was completed using census data on relevant risk factors in Lao PDR. Factors were weighted using an analytical hierarchy process. Village risk scores were calculated using a weighted linear combination and categorised using the Fisher-Jenks algorithm into low, medium, and high risk. District risk scores and categories were calculated using the mean village risk score for a district. Sensitivity analysis was completed by doubling and halving risk factor weights, one at a time, and assessing the standard deviation of scores and categories across all scenarios.

RESULTS

A total of 2017 (23.7%) villages were classified as high risk, with 3312 (39.0%) medium and 3170 (37.3%) low risk. This resulted in 21 (14.2%) high-risk districts, 83 (56.1%) medium and 44 (29.7%) low-risk districts. The risk maps highlight two areas of interest which are high risk and low variation. The first is the northern province of Phongsaly, which is consistent with literature and anecdotal reports. The second is the southern Salavan and Xekong provinces, which have yet to be investigated in detail.

CONCLUSIONS

Multicriteria decision analysis has provided a simple, rapid, and flexible approach to mapping the risk of T. solium in Lao PDR. The nature of the method means that it can be completed in any endemic country with available and appropriate risk factor data.

A Spatial Autocorrelation Method for Taenia solium Risk Mapping: The Case of Lao PDR

BACKGROUND

The World Health Organization has identified Taenia solium mapping tools as an important development for intensifying control in hyperendemic areas. Taenia solium has also been identified as a priority by the Lao PDR government. There is a limited understanding of the distribution of T. solium due to inherent diagnostic challenges.

METHOD

Global and local autocorrelation statistics were applied to available risk factor data sourced from national censuses to map the risk of Taenia solium in Lao PDR.

RESULTS

Approximately 50% of villages could be considered hot spots for one or more risk factors. Different risk factor hot spots co-occurred in 30% of villages. Twenty per cent of villages were classified as hot spots for the proportion of households owning pigs and another risk factor. Northern Lao PDR was the dominant high-risk area. This is consistent with passive reports, limited surveys, and anecdotal reports. One smaller area in southern Lao PDR was also identified as high-risk. This is of particular interest because T. solium has not previously been investigated in this area.

CONCLUSIONS

The methods applied provide a simple, rapid, and versatile approach that allows endemic countries to begin mapping the risk of T. solium at a sub-national level.

An overview of human helminthioses in Vietnam: Their prevention, control and lessons learnt

In Vietnam, helminthioses remain a major threat to public health and contribute to the maintenance of poverty in highly endemic regions. Through increased awareness of the damaging effects caused by helminthioses, the Vietnamese government has implemented many national programs over the past 30 years for the prevention and control of the most important helminthioses, such as, lymphatic filariasis, soil transmitted helminths, food borne zoonotic helminths, and others. Various control strategies have been applied to reduce or eliminate these worms, e.g. mass drug administration, economic development, control of vectors or intermediate hosts, public health interventions through education, proper composting procedures for excreta potentially containing helminth eggs, and the expansion of food supply chains and improved technologies for the production and inspection of food products. These control measures have resulted in a significant reduction in the distribution and transmission of helminth infections and have improved the overall living conditions and health outcomes of the Vietnamese citizens. However, the persistence of several helminth diseases continues in some endemic areas, especially where poverty is widespread and local traditions include the consumption of raw foods, especially fish and meats. This manuscript provides an overview of the helminth infection prevention and control programs conducted in Vietnam, their achieved results, learned lessons, and future works.

Sub-lineages of Taenia solium Asian Genotype Recorded in North India

PURPOSE

Porcine cysticercosis is a neglected zoonotic disease of significant veterinary and medical importance owing to its economic impact and public health significance. The present study aimed at genetic characterization of Taenia solium metacestodes in slaughtered pigs of Haryana (North India).

METHODS

A total of 213 (160 and 53 from Chandigarh and Hisar, respectively) slaughtered pigs intended for human consumption were screened for the presence of T. solium metacestodes. The retrieved metacestodes were confirmed molecularly based on the partial amplification of mitochondrial cytochrome c oxidase subunit 1 (CO1) gene. Evolutionary divergence, haplotype and nucleotide diversities and neutrality indices of the retrieved isolates were also assessed.

RESULTS

Out of the 213 pigs, 2 (0.94%) revealed the presence of metacestodes involving 1 pig each from Chandigarh (0.62%) and Hisar (1.9%). The sequences obtained after custom sequencing were submitted to GenBank under the accession numbers LC661682-83. The present study haplotype clustered with haplotypes of Asian origin and showed variation from other haplotypes by 1-23 mutational steps. However, the present study isolates also showed nucleotide polymorphisms (A198T, A199G, A201T, G204A, T206A, C210T, T212G, T213A, T216G/A, T217C, T221C, C524T, G994A) at different positions, which indicated the presence of sub-lineages. Low nucleotide diversity (π = 0.020) and negative value of Tajima's D (- 1.304) observed for the haplotypes under consideration was indicative of purifying selection and recent population expansion.

CONCLUSIONS

Our study confirms the circulation of T. solium Asian genotype (with distinct sub-lineages) in study area and recommends strict control measures to contain the zoonotic disease.

Seroprevalence and risk factors of porcine cysticercosis: A cross-sectional study in Indonesia

Background and Aim:

Cysticercosis is a zoonotic disease with a global concern. Estimation of the prevalence and identification of potential risk factors are necessary for the prevention and control of the disease. This study aimed to estimate the seroprevalence of cysticercosis and the correlation of the increased prevalence with several potential risk factors.

Materials and Methods:

The seroprevalence of cysticercosis was conducted using an enzyme-linked immunosorbent assay (ELISA), developed by the Institute of Tropical Medicine Antwerp, to detect Cysticercus cellulosae. This study used serum samples from 62 pigs taken from two regencies on Timor Island. The data analysis was performed using SPSS software 20.0 (IBM Corp., NY, USA) to evaluate ELISA results and the strength of the relationship between risk factors and the prevalence of disease using the odds ratio (OR).

Results:

Serum samples from 18 out of the 62 pigs were found to be positive; the seroprevalence of cysticercosis was 29%. The results showed that an extensive farming system led to a higher prevalence of cysticercosis compared to an intensive farming system, namely, 10 out of 18 (56.6%), and that the possibility of identifying cysticercosis in pigs in an extensive farming system was 5 times greater than that in pigs in an intensive farming system. In addition, the results showed that nine out of 18 households who did not have toilet facilities were found to be seropositive, indicating a significant relationship between the risk factor of toilet availability with cysticercosis in pigs, with an OR of 4.5. In addition, the results showed that there was no significant relationship between the risk factor of the feed source and the prevalence of cysticercosis in pigs.

Conclusion:

It can be concluded that the seroprevalence of cysticercosis was 29% in domestic pigs of Timor Island. The risk factors of an extensive pig farming system andtoilet availabilityin community houses were significantly related to the possibility of cysticercosis on Timor Island.

Transcriptome Analysis and Autophagy Investigation of LoVo Cells Stimulated with Exosomes Derived from T. asiatica Adult Worms

Taenia asiatica is a zoonotic parasite found in the human intestine and pig liver that evolved various strategies to survive the host’s defenses. Exosomes are membranous vesicles released by cells and are an important vehicle in parasite-host interactions. However, no literature exists on the specific infection mechanisms of T. asiatica against the host defense response, and further research is required to understand the parasite-host interaction. In this study, we investigated the host’s differentially expressed genes (DEGs) while stimulating them with exosomes derived from the T. asiatica adult worm (Tas-exo) on LoVo by RNA-seq analysis. Our results identified 348 genes as being significantly differentially expressed for the Tas-exo group when comparing with that of the NC group. Some of these genes are related to modulation of cell proliferation and cell autophagy. Surprisingly, autophagy and cell proliferation have crucial roles in the defense against parasites; accordingly, we detected cell proliferation and autophagy in LoVo cells by CCK8, immunofluorescence, and Western blotting, demonstrating that Tas-exo could inhibit LoVo cell proliferation and autophagy via AMPK pathway. When P62 and p-mTOR/mTOR expression were significantly increased, BeclinI and pAMPK/AMPK were significantly decreased. These results expand our understanding of parasite-host interactions mediated by exosomes.

Occurrence of a Hybrid Between Taenia saginata and Taenia asiatica Tapeworms in Cambodia

Human infection with Taenia asiatica or a hybrid between Taenia saginata and T. asiatica has not been reported in Cambodia. We detected for the first time a hybrid form between T. saginata and T. asiatica in Preah Vihear Province, Cambodia. An adult tapeworm specimen, i.e., 75 cm long strobila without scolex, was expelled from a 27-year-old man after praziquantel medication and purging. It was morphologically indistinguishable between T. saginata and T. asiatica. Several proglottids were molecularly analyzed to confirm the tapeworm species. The mitochondrial gene encoding cytochrome c oxidase subunit 1 (cox1) and nuclear genes encoding elongation factor-1α (ef1) and ezrin-radixin-moesin (ERM)-like protein (elp) were sequenced, and a single-allele analysis was performed to confirm the haploid genotype. The results revealed that our sample showed a discrepancy between the mitochondrial and 2 nuclear genes. It possessed homozygous sequences typical of T. saginata at cox1 and ef1 loci. However, it was heterozygous at the elp locus, with 1 allele in T. asiatica (elpA) and 1 in T. saginata (elpC), which indicates that it is a hybrid between T. saginata and T. asiatica. The present results confirmed the presence of a hybrid between T. saginata and T. asiatica in Cambodia and strongly suggest the existence of also ‘pure’ T. asiatica in Cambodia.

Taenia solium taeniasis/cysticercosis: From parasite biology and immunology to diagnosis and control

Infection with the pork tapeworm (Taenia solium) is responsible for a substantial global burden of disease, not only restricted to its impact on human health, but also resulting in a considerable economic burden to smallholder pig farmers due to pig cysticercosis infection. The life-cycle, parasitology and immunology of T. solium are complex, involving pigs (the intermediate host, harbouring the larval metacestode stage), humans (the definitive host, harbouring the adult tapeworm, in addition to acting as accidental intermediate hosts) and the environment (the source of infection with eggs/proglottids). We review the parasitology, immunology, and epidemiology of the infection associated with each of the T. solium life-cycle stages, including the pre-adult/adult tapeworm responsible for human taeniasis; post-oncosphere and cysticercus associated with porcine and human cysticercosis, and the biological characteristics of eggs in the environment. We discuss the burden associated, in endemic settings, with neurocysticercosis (NCC) in humans, and the broader cross-sectoral economic impact associated both with NCC and porcine cysticercosis, the latter impacting food-value chains. Existing tools for diagnostics and control interventions that target different stages of the T. solium transmission cycle are reviewed and their limitations discussed. Currently, no national T. solium control programmes have been established in endemic areas, with further work required to identify optimal strategies according to epidemiological setting. There is increasing evidence suggesting that cross-sectoral interventions which target the parasite in both the human and pig host provide the most effective approaches for achieving control and ultimately elimination. We discuss future avenues for research on T. solium to support the attainment of the goals proposed in the revised World Health Organisation neglected tropical diseases roadmap for 2021-2030 adopted at the 73rd World Health Assembly in November 2020.

Prevalence of meat-transmitted Taenia and Trichinella parasites in the Far East countries

Taenia and Trichinella parasites are globally distributed foodborne zoonotic pathogens transmitted from animal to humans via consumption of raw or undercooked meats. This short review is intended to provide the parasites community a snapshot of the literature on the current and recent prevalence of taeniasis and trichinellosis in humans and animals in the Far East countries. Prevalence rates in these countries are highly diverse due to differences in development, culture, ethnic and religious background, animal forming practices, and eating habits. Taenia and Trichinella remain as important meat-transmitted pathogens in the Far East. A One Health approach is needed to eliminate or continuously reduce the foodborne zoonotic taeniasis and trichinellosis in the Far East.

TSOL18 vaccine and oxfendazole for control of Taenia solium cysticercosis in pigs: A field trial in endemic areas of Tanzania

A field trial was conducted in Tanzania to determine the effectiveness of TSOL18 vaccine used concurrently with oxfendazole (OFZ), and of OFZ alone, on T. solium cysticercosis determined by organ and half carcase dissection of slaughter age pigs. This study followed a quasi-experimental group design. Suitable trial sites were randomly allocated to either treatment group T1 (OFZ treatment alone [30mg/kg, Paranthic 10%]) or T2 (TSOL18 [1ml, Cysvax] plus OFZ). Three 4-monthly treatments were administered to eligible pigs. A random selection of pigs were necropsied at baseline and at endline, 2–3.5 months after the final treatment. Additionally, untreated pigs from T1 and T2 areas were necropsied at endline to provide contemporaneous comparisons with T1 and T2 pigs. Baseline prevalence of viable T. solium cysticerci for T1 was 25.5% (Exact 95% CI: 13.9, 40.3; n = 12/47), and for T2 was 12.0% (CI: 6.4, 20.0; n = 12/100). At endline, prevalence was 2.8% for T1 (CI: 0.1, 14.5, n = 1/36) and 0% for T2 (CI: 0, 4.7, n = 0/77). Among untreated pigs, three had viable cysticerci, one from T1 area (12.5%, CI: 0.3, 52.7; n = 1/8) and two from T2 area (5.7%, CI: 0.7, 19.2, n = 2/35). Fisher’s exact test showed significant changes in prevalence from baseline to endline in both groups (T1: p = 0.005, T2: p = 0.001). Firth’s penalized Maximum Likelihood method suggested the changes were not significant relative to their controls (T1: p = 0.245, T2: p = 0.076). These findings showed a significant reduction in the prevalence of viable cysticerci from baseline to endline after both interventions. However, the changes could not be definitively attributed to the interventions due, in part, to small numbers of control pigs. Concurrent administration of the TSOL18 and OFZ cleared infection among assessed pigs whereas infection remained after treatment with OFZ only. Further studies including larger sample sizes would be required for more definitive conclusions. A One Health approach is recommended for rapid and sustainable impact.

The pork tapeworm T. solium affects the health and income of poor people in endemic areas. A pig vaccine—TSOL18, and a drug—oxfendazole (OFZ) present options for its control. In this study we assessed the effectiveness of the two tools against the parasite in pigs. We provided one group of pigs (T1) with a concurrent administration of TSOL18 and OFZ, and another group (T2) with OFZ only, in three rounds at 4 months intervals. We compared infection prevalence before and after the interventions by detection of cysticerci through carcase dissections. In addition, untreated pigs from the T1 and T2 areas were also sacrificed to serve as controls. We found a significant reduction in prevalence within the groups after the interventions. However, the reductions were not significant when compared with the reductions in the control groups, hence could not be definitively attributed to the interventions. Further, concurrent administration of TSOL18 and OFZ cleared infection among assessed pigs whereas OFZ alone did not clear the infection. Further studies would be required to make more definitive conclusions. We advocate for a One Health approach for a more rapid and sustainable impact.

Endemicity of Taenia solium cysticercosis in pigs from Mbeya Rural and Mbozi districts, Tanzania

BACKGROUND

Taenia solium taeniasis/cysticercosis is a disease of substantial economic and public health importance particularly in low-income countries. The disease was reported to be endemic in Mbeya Rural and Mbozi districts, in the southern highlands of Tanzania, the major pig production area in the country. In 2008, using B158/B60 antigen detection enzyme-linked immunosorbent assay (Ag-ELISA), porcine cysticercosis prevalence of up to 32% was reported in the districts. A number of interventions have been implemented in selected villages including an integrated approach consisting of improving pig confinement and selective treatment of pigs with oxfendazole. Mass drug administration with praziquantel targeting schistosomiasis, with an expected effect on T. solium, was also provided to school-age children in the area. This study aimed at providing an update on prevalence and intensities of porcine cysticercosis; and assessing farmers' knowledge, attitudes and practices which could be associated to disease transmission in the area. The study involved a questionnaire survey conducted using face-to-face household interviews with 890 consenting farmers; and carcass dissections performed on 282 pigs randomly selected from the surveyed households.

RESULTS

Twenty-six pigs (9.2%) were infected with T. solium; of which two-thirds (65.4%) had light to moderate infection intensities (1-1000 cysticerci), and one-third (34.6%) had heavy intensities (> 1000 cysticerci). Questionnaire results showed that only 5.7% of the respondents perceived T. solium cysticercosis to be an important disease in pigs. About 18.5% of the respondents were aware of T. solium taeniasis, but 32% of them were unaware of how the infection is acquired. Half of the respondents had seen cysticerci in pork, of whom 61% were not aware that consumption of infected pork could cause taeniasis. Latrines were observed to often (90%) lack doors with 45% considered accessible to pigs.

CONCLUSIONS

This study provided an evidence that the disease was still endemic in the area. Poor knowledge of farmers, attitudes, and risky practices responsible for disease perpetuation were also revealed. A One Health approach targeting the whole area incorporating improvement of farmer knowledge regarding disease transmission needs to be trialed as a feasible approach to control.

Epidemiology of Taenia saginata taeniosis/cysticercosis: a systematic review of the distribution in East, Southeast and South Asia

BACKGROUND

Taenia saginata is an important zoonotic parasite, causing taeniosis in humans and cysticercosis in bovines, the latter being a significant concern for the global beef industry. Many countries in East, Southeast and South Asia are experiencing rapid economic growth, and an increasing number of people in these countries are dependent on the livestock industry. Currently, however, an overview of the prevalence of T. saginata in this region is lacking. In this review, we analysed the available literature on T. saginata taeniosis and bovine cysticercosis for East, Southeast and South Asia.

METHODS

A systematic review was conducted, based on both published and grey literature. Articles published between 1990 and 2017 were mined for information on the occurrence, prevalence, and geographical distribution of T. saginata taeniosis and bovine cysticercosis in East, Southeast and South Asia.

RESULTS

The presence of T. saginata was described in 15 of 27 countries of the region, including Afghanistan, Cambodia, China, India, Indonesia, Japan, Lao PDR, Malaysia, Mongolia, Nepal, Pakistan, Philippines, South Korea, Thailand and Vietnam. The only country that reported an absence of T. saginata is Japan, although sporadic reports of imported cases and unconfirmed reports of autochthonous infections were identified. Nationwide surveys of taeniosis with systematic sample collection and high sample numbers were available for Cambodia, China, Lao PDR, and South Korea, although speciation of Taenia was not always performed. Regional prevalence of taeniosis and bovine cysticercosis in endemic regions ranged between 0.02-42.6%, and 0.76-46.7%, respectively. However, data for bovine cysticercosis were only available for five countries (Japan, Lao PDR, Mongolia, Pakistan and Vietnam).

CONCLUSIONS

The data indicate a widespread occurrence of T. saginata throughout East, Southeast and South Asia. Identification of Taenia spp. in human infections was frequently not performed, leading to gaps in knowledge about the distribution of human tapeworm infections, mainly in regions where different human Taenia species co-occur. A high prevalence of T. saginata taeniosis and bovine cysticercosis may reflect insufficiencies in sanitation, limited health education standards, and insufficient food safety measures. Therefore, there is a need to improve local surveillance, notification, and overall control systems.

Neurocysticercosis cases identified at Sanglah Hospital, Bali, Indonesia from 2014 to 2018

Neurocysticercosis (NCC) was first reported in the province of Bali, Indonesia in 1975. Since this time, sporadic cases have been reported annually. This study reports information on 29 NCC cases (20 males and 9 females) admitted to a referral hospital in Denpasar, Bali from 2014 until 2018. Twenty-four cases were from Bali, 2 were from the province of East Nusa Tenggara, and 3 were from the Democratic Republic of Timor-Leste. Mean patient age was 37.2 years and 69.0% (20/29) were male. Epileptic seizures were the most common clinical manifestation (65.5%, 19/29). Serology (ELISA) was used in 14 cases (48.2%, 14/29), but only 6 cases, including one case with an inactive calcified lesion, were positive (42.9%, 6/14). Two cases underwent surgical resection after their lesions were initially misdiagnosed as brain tumors. These hospital-based findings are discussed along with the present status of NCC in Bali.

Zoonotic transmission of intestinal helminths in southeast Asia: Implications for control and elimination

Intestinal helminths are extremely widespread and highly prevalent infections of humans, particularly in rural and poor urban areas of low and middle-income countries. These parasites have chronic and often insidious effects on human health and child development including abdominal problems, anaemia, stunting and wasting. Certain animals play a fundamental role in the transmission of many intestinal helminths to humans. However, the contribution of zoonotic transmission to the overall burden of human intestinal helminth infection and the relative importance of different animal reservoirs remains incomplete. Moreover, control programmes and transmission models for intestinal helminths often do not consider the role of zoonotic reservoirs of infection. Such reservoirs will become increasingly important as control is scaled up and there is a move towards interruption and even elimination of parasite transmission. With a focus on southeast Asia, and the Philippines in particular, this review summarises the major zoonotic intestinal helminths, risk factors for infection and highlights knowledge gaps related to their epidemiology and transmission. Various methodologies are discussed, including parasite genomics, mathematical modelling and socio-economic analysis, that could be employed to improve understanding of intestinal helminth spread, reservoir attribution and the burden associated with infection, as well as assess effectiveness of interventions. For sustainable control and ultimately elimination of intestinal helminths, there is a need to move beyond scheduled mass deworming and to consider animal and environmental reservoirs. A One Health approach to control of intestinal helminths is proposed, integrating interventions targeting humans, animals and the environment, including improved access to water, hygiene and sanitation. This will require coordination and collaboration across different sectors to achieve best health outcomes for all.

Taeniasis and cysticercosis in Asia: A review with emphasis on molecular approaches and local lifestyles

Taeniasis is an important parasitic condition in Asia, especially since all three human-infecting Taenia spp., Taenia solium, Taenia saginata, and Taenia asiatica are found in this region. These three species are believed to be sympatrically distributed, with the largest disease burden found in remote and rural areas where people raise pigs and cattle in a traditional manner. Recent studies revealed that T. asiatica and T. saginata are genetically-related sister species that are not completely reproductively isolated from each other. Current evidence indicates that most T. asiatica adult worms are hybrid-derived descendants. Moving forward, nuclear DNA analysis will be critical in further assessing the species circulating locally. Lifestyle choices, such as the consumption of undercooked meat, are important in maintaining the life cycles of these parasites. In addition, poor hygiene and sanitation, in highly endemic areas, make disease control difficult, resulting in the need for sustainable education programs. An overview of the present situation of taeniasis and cysticercosis in Asia is provided, followed by a discussion of molecular approaches to species assessment and the impact of human lifestyles on parasite transmission.

Impacts of using the electronic-health education program 'The Vicious Worm' for prevention of Taenia solium

BACKGROUND

Taenia solium is a zoonotic tapeworm widely distributed across sub-Saharan Africa. Specific health education is regarded as a central element in controlling T. solium. In 2014, an electronic health education tool called 'The Vicious Worm', which was concerned with prevention of T. solium was introduced to health and agricultural professionals in Mbeya, Tanzania, an endemic setting. Introduction to ´The Vicious Worm' of 1.5 hours significantly improved the participants' knowledge. This study revisited the same study subjects one year later to assess persistence of knowledge regarding T. solium taeniosis/cysticercosis and to assess if the health education had changed work practices for the participants and the public.

METHODS

The study was conducted in Tanzania between June and August 2015, with a fixed population of health and agricultural professionals recruited from a previous study testing 'The Vicious Worm'. The study used a test, a questionnaire survey, as well as semi-structured group and individual interviews.

RESULTS

The 79 study subjects, all health or agricultural professionals, had within one year relocated from Mbeya to 16 of 21 administrative regions of Tanzania. Sixty-four agreed to participate in the test and 48 to an interview. The test showed significant improvement in knowledge regarding T. solium taeniosis/cysticercosis, compared with the baseline knowledge level of the participants. Interview data found that the participants had used 'The Vicious Worm' as an educational tool and applied the knowledge from the program to implement new practices consisting of by-laws and practical workshops on building latrines, pig pens and hand washing stations in their communities.

CONCLUSION

Introduction to 'The Vicious Worm' led to changed practices and persistence in knowledge regarding T. solium. Incorporating health education as a specific health intervention tool should be encouraged and implemented at national or programmatic level.