Orchidée: a national federated hospital network for automated epidemiological surveillance in France

Orchidée is a federated hospital surveillance network funded under EU4Health, launched on October 1st, 2024. Coordinated by Santé publique France (SpF), University Bordeaux/BPH, the Health Data Hub (HDH), and 26 university hospitals, it automates the extraction of epidemiological indicators from hospital clinical data warehouses (HCDW), with Severe acute respiratory infection (SARI) as the priority theme. Four work packages structure the project: coordination (SpF), scientific development (BPH), data warehouse strengthening (HDH), and European data integration (SpF). Six working groups address six public health priorities, each co-led by experts from consortium hospitals and SpF. For SARI, a standardised pipeline covers case definitions, indicator specifications, data flows, standardised scripts, and reporting. Core indicators —hospital admissions, ICU admissions, and in-hospital deaths — are ICD-10 aligned and categorised as reactive, specific, or sensitive. Implementation followed a phased approach from a pilot site to ten hospitals, now being generalised to all 26. By April 2026, five deliverables and eight milestones have been reached. Routine automated SARI indicator transmission to SpF is operational in half the network. Key outputs include the Orchidée indicator specification template and a validated cyclical surveillance process. Four further thematic groups (healthcare-associated infections, antimicrobial resistance, severe bacterial infections, arboviruses) have reached consensus on priorities; traumatisms was recently added. Challenges remain regarding HCDW heterogeneity, data standardisation, and metrological validation. Orchidée has met its midpoint objectives. Next steps include completing SARI transmission across all hospitals, evaluating network added value, deploying the framework to other themes, and advancing European data integration. Its federated architecture provides a sustainable, scalable foundation for France’s public health surveillance.

Key messages

• Orchidée: a national federated network automating epidemiological surveillance across 26 French university hospitals, on track at mid-term with SARI indicator transmission operational.

• Orchidée currently has automated SARI reporting in half the network, standardized processes, and expanded themes—now advancing toward full hospital coverage and European integration.