Design Thinking for Soil-Transmitted Helminths Prevention

Introduction

Helminthic parasites affect more than one third of the world’s population and cause substantial disease and disability. This neglected disease involves human, animal and environmental health as a biology of the disease. Because of the role of contaminated soil in their transmission, infections with Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, and hookworm (Ancylostoma duodenale and Necator americanus) are, in public health terms, known as soil-transmitted helminthiasis (STH). STH infections generally infect populations of school-age and pre-school children. Both of these population groups are very susceptible to worm infections, which are often not detected. STH infections typically have a very low mortality rate but cause morbidity that can affect a person’s quality of life for a long time. To control the diseases, World Health Organization (WHO) road map by the year 2021-2030 was proposed to manage the neglected tropical diseases (NTDs), including STH diseases, was on the list as well. The objectives of this project were 1) to set up a soil-transmitted helminth stakeholder meeting and implement the design thinking concept and process to the stakeholders for the pre-prototype development and 2) to develop at least one useable prototype regarding soil-transmitted helminth prevention by design thinking process.

Methods

In this project, the stakeholders were invited as this disease is a complicated problem so we need multidisciplinary team to solve the problem. The representatives of the Departments of Helminthology and Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Department of Parasitology, Faculty of Kasetsart University, Tha Song Yang district public health (Tak province), sub-district health promoting hospital, sub-district administrative organization, village health volunteers, head of the community, and primary-school teachers were invited to join this workshop. A workshop on design thinking for the prevention of soil-transmitted helminth infection was held on November 3-4, 2021 at the Tha Song Yang Public Health Office. Based on the One Health approach, information on soil-transmitted helminths, and design thinking principles and activities.

Ethanol extractions of Ma-Fuang fruit, Ba-San fruit, and Sab-Suea leaf were prepared. Acetic acid was used as a positive control, and DMSO and ethanol were used as solvent controls. Each in vitro reaction was composed of herb compound and egg-containing larva or dividing cells (approximately 100 eggs). The reaction was incubated for 30 s at room temperature. Then, 0.2% eosin was added, and the mixture was mouthed on the glass slide and observed. A total of 10 eggs were counted (in triplicate) for larva or cell movement. Eosin staining (red color which represented the dead eggs or larvae) was applied under a light microscope at 100X or 400X magnification. According to the in vitro result, we prepared the combination of the “Design thinking herb spray” as follows: Ma-Fuang, Sab-Suea and ethanol (dark green liquid), and sent to the herb spray for in vitro skin irritation test, which was based on the utilization of the reconstructed human epidermis, which closely mimics the biochemical and physiological properties of the upper parts of the human skin (the epidermis).

Results and Discussion

The good practice or main strength of this project is the design thinking process, which integrates health and non-health science aspects in creating a pre-prototype based on complicated problems or pain points. Moreover, the useable herb spray product was developed from a real problem in the community.

An obstacle faced in implementing this project was that the workshop was set up during the COVID-19 pandemic, which led to a limited number of participants and thus a limited number of ideas for pre-prototypes. The lesson learnt regarding the future design thinking workshop might be organized online to attract a large number of participants in the context of the COVID-19 health crisis.

The participants proposed two pre-prototypes: an herbal spray and a no-rinse hand-soap tablet. The selected pre-prototype was the herbal spray, from which a useable prototype will further be developed. The participants from the herbal spray group recommended three local herbs as spray ingredients—the star apple (Averrhoa carambola, or Ma-Fuang in Thai) flower or fruit, the great elephant apple (Dillenia aurea, or Ba-San in Thai) fruit, and the Siam weed or Sab-Suea (Chromolaena odorata L.) leaf—to protect local communities from helminth infective eggs when eating barehanded. For the in vitro experiment, it was shown that with the combination of ethanol extraction of Ma-Fuang fruit and Sab-Suea leaf at the final concentration of 50 mg/ml, the cells and larva stopped their movement and stained with a red color. It was shown in the results that the combination of ethanol extraction of Ma-Fuang fruit and Sab-Suea leaf, with the lowest LC50 of 6.86 mg/ml might affect the parasite eggshell and larvae due to its high toxicity. It was shown in the results that the herb spray decreased tissue viability (mean 22.01%, SD 8.582), which indicates an irritant effect. However, a contact time of 15 min was performed in this protocol. Therefore, we recommend that users in the community apply this herb spray to their hands, wait for 30 s, and wash their hands out. This protocol should be sufficient to inhibit parasite eggs and decrease skin irritation.

We plan to contact the Tha Song Yang Public Health Office and village health volunteers to distribute the herb spray and provide instructions to the community. The expected outcome from the project such as decreasing of the infected cases in the future and the community will concern about the STHs regarding health policy. This model might be used by the other community area with affected by STHs in the national, regional and global.

SEAOHUN 2022 Small Grants

Project team leader:Dr. Sivapong Sungpradit

Team members: . Asst.Prof. Dr. Teera Kusolsuk, Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Asst.Prof.Dr. Jitjayang Yamabhai, Asst.Prof.Dr. Patoo Cusripituck, Research Institute for Languages and Cultures of Asia, Mahidol University

- Personal protective equipment, distancing, and group size standards in this photo were consistent with local public health guidance and COVID-19 status in the specific country and time it was taken. This may not reflect best practices for all locations where COVID-19 is still spreading. -