“Drawing Thresholds That Make Sense” : Diagrammatic Evidence and Urgency in Automatic Outbreak Detection

Abstract

This chapter discusses the aesthetic and affective ordering of evidence practices in the context of epidemiological surveillance. The author focuses on the medium of the signal report that is used by public health agencies and epidemiologists in Germany to retrieve automatic warnings about possible outbreaks. The emergence of such an infrastructure for automatic outbreak detection is historically situated in international developments toward anticipatory biosecurity since the 1990s, both on the level of policy-related concepts and of algorithmic implementation. The chapter compares different designs of signal reports at the national center for disease control in Germany and reconstructs the particular role of control charts for making visible the computational context of early warning signals. Theoretically, signals are conceptualized as objects with evidentiary potential that affectively lure epistemic action. Moreover, tracing the infrastructure and media for signal reporting brings to light differing attitudes toward the evidentiary contribution of automatic recommendation systems and how boundaries between different traditions of expertise are secured.