Disease X represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease, and so the R&D Blueprint explicitly seeks to enable cross-cutting R&D preparedness that is also relevant for an unknown “Disease X” as far as possible.
The idea here is to build a mechanism akin to a machine-actionable Data Management Plan, but instead of being for a single research project, it would be designed for handling data flows throughout the "Disease X" outbreak(s), including for aggregation over time, jurisdiction, projects and other things.
The WHO List of Blueprint priority diseases includes "Disease X", described as
The idea here is to build a mechanism akin to a machine-actionable Data Management Plan, but instead of being for a single research project, it would be designed for handling data flows throughout the "Disease X" outbreak(s), including for aggregation over time, jurisdiction, projects and other things.