Project's information

Project's title Foodborne Zoonotic Trematode Infections and Integrated Control in Vietnam
Research hosting institution Institute of Ecology and Biological Resources
Coordinating unit, co-chair University of Liège (2017-2020), Free University of Brussels (2020-2023).
Project leader’s name PhD. Bui Thi Dung; Prof. Bertrand Losson (2017-2020) and Prof. Olivier Vandenberg (2020-2023)
Project duration 01/07/2017 - 31/08/2023
Project’s budget 4,586,690,700 VND
Classify Grade A
Goal and objectives of the project

- Determining the status of FZTi infection in different hosts and in the environment. Evaluation of factors influencing fluke infection in humans such as behavior and eating habits. All these data will be combined in a risk analysis.
- Develop an integrated control strategy. These diseases have a complex life cycle and epidemiology. The problem of trematode control will require the integration of different medical and veterinary principles, biology, food science and socio-anthropology to develop a sustainable integrated control strategy. and reasonable.
- Evaluation of existing diagnostic tools and their implementation should be carried out. New diagnostic tools can be developed if necessary according to preliminary assessment.
- Raising awareness and building research capacity on FZTi. Enhance cooperation among representative partners in Vietnam and build effective research network.

Main results

Scientific Results:
(1) The habit of eating raw fish as “fish salad” and eating raw vegetables is very popular and is a long-standing eating habit that has existed for generations in Thanh Hoa and Yen Bai provinces. In Thanh Hoa, the source of fish used to eat fish salad is mainly from ponds and rivers, fish species often eat raw: silver carp, ray-finned fish, sharpbelly fish, and swamp ell. Knowledge, attitude and practice of local people are relatively low. But after media intervention, people's knowledge, attitudes and practices about foodborne zoonotic trematodes prevention have improved.
(2) The prevalence of small liver fluke infection in humans is 40.2%, large liver fluke 5.64%, intestinal fluke 15.9%. The prevalence of trematode infection in men is higher than in women, and is common between the ages of 31 and 50 years old. The prevalence of small liver fluke and intestinal fluke in dogs and cats was 19.6% and 47.1% in Yen Bai, and 10.4% and 11.8% in Thanh Hoa, respectively. The prevalence of fascioliasis in both provinces was 19.4%. Fish species infected with small liver fluke metacercaria: ray-finned fish, sharbelly and predatory carp. All 10 tested fish species were infected with intestinal fluke metacercariae. Snails act as intermediate hosts of the small liver fluke: Parrafosarulus striatulus. Snails act as intermediate hosts of the liver fluke Austropeplea viridis.
(3) Biological control of tapeworm eggs in animals: for small liver fluke eggs use strain VTCC 31150 Trichoderma koningii, for large fluke eggs use VTCC 30706 Paecilomyces lilacinus. Biological control of snails by nematodes: strain Heterorhabditis indica DL1 (150 IJs/10 µl) causes mass death, strain Phasmarhabditis hermaphrodita can reproduce in snail carcasses. Biological control of snails with essential oils (menthol, basil, lemongrass and cinnamon) was able to completely kill Austropeplea viridis snails at concentrations of more than 0.125% and their toxicity was dose dependent. Alcohol 55% can inactivate cyst metacercaria of small liver fluke after 60 hours. Acetic acid and potassium permanganate have the ability to destroy metacercariae of large liver fluke with concentrations (62-66%) and (38-66%), respectively.
(4) The diagnostic techniques for parasites at provincial, district and commune levels in Yen Bai and Thanh Hoa provinces are mainly stool testing. Thanh Hoa province has ELISA equipment, but it is rarely used. The project has successfully trained on theory and practice of trematode diagnostic techniques 32 health workers from 2 provinces of Yen Bai and Thanh Hoa (provincial, district and commune levels).
(5) The project has organized communication, distributed leaflets, posted posters, reported on information about foodborne zoonotic trematode infections and transmission routes as well as prevention and awareness raising for people in 4 communes (Phuc An, Vu Linh, Ha Duong, Ha Vinh). Annual steering committee meeting to report research results to policy makers, WHO, Ministry of Health.
Results of application: 
Application and transfer of trematodes diagnostic techniques from Belgian experts (Kato Katz technique, Formalin - Ether Concentration Technique-FECT, Fluke-finder, ELISA)
Results of training: 
03 doctors, 04 masters, training in trematode diagnostic techniques for 32 health workers at the provincial, district and commune levels in the two provinces of Yen Bai and Thanh Hoa.
Results of collaborative development: 
The project has succeeded in building multidisciplinary cooperation relationships with Belgian and domestic experts from different fields: human medicine, veterinary medicine, fisheries, environment according to One Health 

Novelty and actuality and scientific meaningfulness of the results

Contributing new general data on fluke infections in humans, animals, fish, snails, and the environment. The project has successfully developed a sustainable integrated control strategy based on a combination of medicine, veterinary medicine, fisheries, biology, food science and socio-anthropology. Transferring new diagnostic techniques from Belgian experts (flukefinder technique), improving ELISA technique to increase the accuracy of results.

Products of the project
- Publications: 
5 ISI papers (3 SCIE Q1, 1 SCIE Q3, 1 ISBN Journal), 
Nguyen TTB, Dermauw V, Dahma H, Bui DT, Le TTH, Phi NTT, Lempereur L, Losson B, Vandenberg O, Do DT, Dorny P.*, 2020. Prevalence and risk factors associated with Clonorchis sinensis infections in rural communities in northern Vietnam. PloS Negl Trop Dis, 14(8): e0008483. SCIE Q1
Phuong Thi Xuan Nguyen, Hien Van Hoang,  Pierre Dorny, Bertrand Losson, Dung BT*, Laetitia Lempereur., 2021. Insights on foodborne zoonotic trematodes in freshwater snails in North and Central Vietnam. Parasitol Res. 120(3):949-962. doi: 10.1007/s00436-020-07027-1. SCIE Q1
Thao Thi Bich Nguyen*, Veronique Dermauw, Dung Thi Bui, Hafid Dahma, Dung Thuy Le, Hien Thi Thu Nguyen, Dung Trung Do, Pierre Dorny, Bertrand Losson, Olivier Vandenberg, 2023. Incidence of fish-borne trematode infections and associated factors: results from a cohort study in highly endemic communities in northern Vietnam. Parasitol Res122 (6):1415-1425. doi: 10.1007/s00436-023-07846-y. SCIE Q1
Phi NTT, Nguyen TTB, Le TTH, Do DT, Lenaerts M, Losson B, Vandenberg O, Dorny P, Van Gerven M, Boere-Boonkamp M, Bui TD*,. 2022. Foodborne zoonotic trematode infections in Yen Bai, Vietnam: a situational analysis on knowledge, attitude, and practice (KAP) and risk behaviors. J Prev Med Hyg. 63: E310-E319. SCIE Q3
Trang Le Thi Huyen, Dung Bui Thi, Dung Do Trung, Ngan Phi Thi Thuy, Thao Nguyen Thi Bich, Vandenberg Olivier, Marc Lenaerts, Bertrand Losson, Suporn Thongyan*, 2021. Knowledge, Attitude, Practices related to small liver fluke infections in rural communities of Ha Trung district, Thanh Hoa province, Vietnam. The Journal of Kasetsart Veterinarian. 31, 1-4.
Images of project