Unveiling the climate – health nexus through citizen science: the TRIGGER Climate Health ConnectionLabs

The TRIGGER Horizon Europe project aims to enhance evidence-based connections between climate change and health threats and human well-being.

As clearly emerging in the EXPOSOME paradigm on which the project is rooted, the interactions among climate, health and ecosystems are multiple and complex, and research aiming at identification, monitoring, and quantification of impacts of climate change on human health requires the application of novel and transdisciplinary approaches. To this aim, TRIGGER has envisaged activities in a wide variety of disciplines developed in different real-world contexts considering the climatic, social, economic, and cultural richness of the European continent.

Specifically, TRIGGER has identified a set of five demonstration labs, the Climate Health Connection Labs (CHCLs) in which citizens are part of a codesign mechanism to directly monitor health, weather-climate, environmental and socio-economic data.

These labs operate in five strategically selected cities, Augsburg, Bologna, Geneva, Heraklion, and Oulu, chosen to reflect diverse climatic, socio-economic, and cultural contexts.

The objectives of the TRIGGER CHCLs are to:
• Investigate the complex interplay between climate change and health.
• Define a common language to foster collaboration among stakeholders, including medical, professionals, policymakers, climatologists, patient associations, and citizens, addressing local challenges.
• Provide a platform for interdisciplinary research and robust stakeholder engagement.

To achieve these ambitious aims, the CHCLs implement three interconnected clinical studies—RetroCLAVIS, CrossCLAVIS, and LongCLAVIS, which collectively provide a comprehensive understanding of the climate-health interplay. Each study contributes unique insights while building upon the others to create an integrated, multi-layered approach to identifying risk profiles and actionable interventions.

RetroCLAVIS:
• Retrospectively analyzes pre-existing lifelong health and environmental data.
• Identifies long-term trends and emerging health threats, providing a temporal context to complement acute and longitudinal findings.

CrossCLAVIS:
• Serves as the foundation by analyzing cardiovascular and respiratory disease patterns in real-time across diverse European settings.
• Investigates molecular and microbiological mechanisms, such as the respiratory microbiome and mitochondrial DNA.
• Provides baseline data to inform and validate hypotheses in RetroCLAVIS and LongCLAVIS.

LongCLAVIS:
• Extends CrossCLAVIS findings through a longitudinal study enrolling 300 healthy volunteers.
• Use wearable technology and citizen science to capture detailed data on health, personal and environmental exposures over a one-year period.
• Explores molecular and microbiological pathways underlying climate-driven disease susceptibility.

In this complex scenario, the Bologna CHCL specifically examines how extreme heat and air pollution could trigger cardiovascular and respiratory diseases. This lab combines cross-sectional and longitudinal studies, to analyze environmental exposures and health threats using harmonized datasets.

Overall, this work will present how the CHCL approach in the TRIGGER project provides an innovative, user-centered framework that integrates interdisciplinary collaboration and stakeholder engagement. By enabling capacity-building and deepening the understanding of the climate-health connection, the CHCLs deliver critical insights and practical mitigation and adaptation solutions, advancing societal preparedness for the challenges posed by climate change.