Table 1. Summary of some event-based surveillance systems.

Type	Example	Establishment	Public availability
Moderated systema	Program for Monitoring Emerging Disease (ProMED) (29,30)	In 1994 as a nonprofit organization	Yes
Partially moderated systemb	Global Public Health Intelligence Network (GPHIN) (31–33)	In 1998 through partnership between the Government of Canada and World Health Organization	No; available to partnered health agencies
Fully automated systemc	Medical Information System (MedISys) (36,41,42)	In 2004 by the European Commission	Yes
	HealthMap (35,38,40,43)	In 2006 by Boston Children’s Hospital	Yes
	Pattern-based Understanding and Learning System (PULS) (36,44,45)	In 2007 by the Department of Computer Science, University of Helsinki, Finland	Yes

^a A moderated system: volunteer expert-curators identify, review and validate sources and create the reports

^b A partially-moderated system: automatically acquires, categorizes, and filters sources. Expert-curators moderate the subset of sources and create the reports

^c A fully-automated system: automatically acquires, categorizes, filters and reports the health-related sources