Digitalization of the Mandatory Notifications System for Infectious Diseases in Germany: Implementation of DEMIS (the German Electronic Reporting and Information System).

Background: Mandatory notifications of infectious diseases in Germany were paper based until the implementation of DEMIS (Deutsches Elektronisches Melde- und Informationssystem für den Infektionsschutz; German Electronic Reporting and Information System) in 2020. DEMIS provides technical infrastructure for electronic reporting of infectious diseases to public health authorities, with the goal of streamlining processes through automation and reducing the burden of manual data entry. Objective: DEMIS provides Fast Healthcare Interoperability Resources (FHIR)-based interfaces for mandatory notification systems that can be accessed by multiple authentication methods for different user groups, such as laboratories, hospitals, and public health authorities. In this paper, we describe the implementation of DEMIS from conceptualization to deployment and evaluation as well as the associated challenges. Methods: Conceptualization of DEMIS was initiated in 2012 by the Robert Koch Institute, Fraunhofer FOKUS, and the German Federal Ministry of Health. The implementation was accelerated during the COVID-19 pandemic in 2020 with support from gematik, Germany's national digital health agency. DEMIS uses FHIR interfaces and standardized terminologies, such as LOINC (Logical Observation Identifiers Names and Codes) and SNOMED CT (Systematized Nomenclature of Medicine-Clinical Terms), to digitally submit basic information on notifiers and patients along with specific diagnostics, clinical data, and epidemiological information from physicians and laboratories to public health authorities. The use of FHIR should ensure interoperability with other surveillance systems. DEMIS provides access either directly via an FHIR-based API or through a web portal. Then, DEMIS notifications will be integrated into the recipient's specialized software. The deployment of FHIR packages in DEMIS will be published on simplifier.net. Finally, the notification data coming via DEMIS will be monitored and evaluated thoroughly. The whole process from implementation to deployment should be supported with active communication between stakeholders. Unlabelled: The first surveillance module was deployed for SARS-CoV-2 notifications during the COVID-19 pandemic in 2020. Since then, DEMIS availability has been over 95% per month, and usually above 99%. As of August 2025, there were 697 laboratories, 1670 hospitals, and 870 other institutions such as private test centers, pharmacies, and general practitioners in Germany that have accessed DEMIS via the API. DEMIS has handled roughly 50 million pathogen notifications and 500,000 disease notifications to date, routed to all 376 local public health authorities. For notifiable pathogens, data quality has been routinely assessed and reported back to the laboratories. On average, 92% (92,378/100,579) of the notifications included a LOINC code. Conclusions: DEMIS plays a key role in digitizing health care. It enables secure data exchange across many stakeholders and interoperable data processing across different software systems. Operations have functioned reliably since rollout. Ongoing routine data quality assessment could further enhance DEMIS performance. As DEMIS expands to other surveillance systems, continued discussion on semantic interoperability is necessary.