This symposium will provide context into the origin, current state and future direction of public health informatics as a defined field of program practice and science. Mr. Brand will discuss issues and challenges that directly impact reportable disease surveillance, such as electronic messaging (ELR, HL7/ CDA, eCR), message validation (structural/content, use of staging databases and interface engines), data sharing complexities/platforms (HIEs, AIMS/ RCKMS) and public health informatics infrastructure (organizational differentiation and staffing). Dr. Klompas will discuss a case study from the Massachusetts Department of Public Health, which has been conducting electronic surveillance for sexually transmitted infections using automated analyses of electronic health record data for almost a decade. He will review the history of this program including case detection and reporting strategies, and then explore emerging work on using electronic health record data to summarize testing, treatment, and follow-up patterns at the population level as well as approaches to detecting high risk patients for prospective prevention interventions. Mr. Harrison-Quintana will discuss the use of a social media application, Grindr, to target health messaging directly to end-users. Since its launch seven years ago, Grindr has grown to be the largest network of GBMSM in the world, with tremendous opportunity for public health