# Evidence-based decision-making support for determining the risk of schistosomiasis infection during large events in China: Application of risk assessment

## TL;DR

This study developed a risk assessment system to prevent schistosomiasis during large events in China, successfully applied to three major events in Wuhan.

## Contribution

A structured decision-making support system integrating risk identification, assessment, and control for schistosomiasis during large events in endemic regions.

## Key findings

- The system successfully prevented schistosomiasis transmission during three large events in Wuhan.
- Targeted interventions like environmental hardening and increased monitoring effectively reduced risk.
- Post-event surveillance confirmed the long-term effectiveness of the interventions.

## Abstract

To investigate the application of risk assessment in decision-making support for disease prevention and control during large-scale events involving schistosomiasis, a rapid system and process for assessing the risk of schistosomiasis transmission were developed.

A risk assessment indicator framework was developed through literature reviews and the Delphi method. Risk level determination was assessed using the Delphi method and a risk matrix method. Control measures were implemented based on the risk levels determination. Effectiveness evaluation was verified by monitoring schistosomiasis-related public health incidents and tracking key indicators—including oncomelania snail infection prevalence, snail density, human and livestock infection rates, wild feces detection, and sentinel mouse infection—over 1–3 years post-event, supplemented by repeated risk assessments.

The decision-making support system for schistosomiasis transmission prevention and control during large-scale events comprises a database of recent schistosomiasis cases, onsite schistosomiasis transmission risk monitoring, a case database of outbreaks, a database of assessment experts, a database of the distribution of oncomelania snail, a library of professional strategies, and a preplan. This system encompasses four processes, namely, identification of high-risk factors, risk assessment to determine areas with high, medium and low risk levels, implementation of targeted risk management and control measures, and evaluation of long-term effects.

The risk assessment system was successfully applied to three large-scale events in Wuhan, effectively supporting evidence-based decision-making support and preventing schistosomiasis transmission. Post-event surveillance and reassessment of indicators verified the sustained effectiveness of the interventions. This closed-loop approach demonstrates that risk assessment is a vital tool for public health decision-making during large events in endemic areas.

Organizing large public events like festivals, construction projects, or international games in schistosomiasis-endemic regions requires proactive health risk management. In this study, we developed a decision-making support system for schistosomiasis transmission prevention and control during such events. Our framework integrates risk identification, risk assessment (using expert consultation, Delphi, and risk matrix methods), risk management and control, and effectiveness evaluation. We applied this system to three major events in Wuhan: the International River-Crossing Festival, the Wuhan Changjiang New Area development, and the Seventh World Military Games. We identified high-risk areas by analyzing epidemic surveillance data, oncomelania snail distribution, field risk monitoring, and population vulnerability (e.g., water sports venues near historical oncomelania snail environments). Targeted interventions—such as environmental hardening to eliminate snail habitats, increased sentinel mice monitoring, and public awareness campaigns—effectively prevented outbreaks. Our findings demonstrate that structured risk assessment provides actionable insights for health authorities. This approach balances safety with event feasibility, offering a scalable model for public health decision-making during large gatherings in endemic regions.