Abstract
Genotypic characterization of bacterial isolates provides valuable information for epidemiological surveillance and microbial population biology. In particular, the ability to discern clonal relatedness among isolates can be used to identify links and sites of transmission, some of which are not easily traced using conventional contact investigation. The spatial and temporal clustering of isolates that share the same or closely related genotypes can add further value to the use of molecular fingerprinting in the detection and management of infectious disease outbreaks. This chapter reviews and discusses the use of both spatio-temporal clustering and bacterial genotypes in public health biosurveillance and includes examples of temporal and spatial clustering of bacterial genotypes that allow for the integration of bacterial genotyping into public health decision making.