A protocol for mapping Blastocystis epidemiology and diagnostics from One Health perspective

Blastocystis is a globally prevalent gut protist colonising over a billion people worldwide, yet its epidemiology, transmission dynamics, and clinical significance remain underexplored. This protocol represents the first step of a large-scale effort to map Blastocystis epidemiology and diagnostic practices across Europe through the COST Action CA21105: Blastocystis under One Health. By assessing diagnostic methodologies across clinical, veterinary, and environmental sectors, this work sets the foundation for future research and standardisation. Here, we highlight key findings, challenges, and a roadmap for improving Blastocystis detection, ultimately influencing global health policies and microbial ecology studies.