Another very important step toward an overall global strategy to strengthen surveillance and control diseases at their source is embodied in the revised World Health Organization (WHO) International Health Regulations (IHRs).23 Originally based on its historical development from 19th and early 20th century concerns, the IHRs
formerly required the international reporting of only 4 diseases: cholera, plague, yellow fever, and, until it was eradicated, smallpox. It had been recognized for some time that the regulations were outdated and of limited usefulness in today’s highly globalized world. Consequently, the WHO and World Health Assembly undertook a revision of the IHRs, in an effort led by David Heymann, as a mechanism to strengthen surveillance and response. This process was completed in 2005, and the new regulations, called IHR (2005), entered into force in 2007. According to WHO, the purpose and scope of the IHR (2005) are to prevent, protect against, control and provide a public health response to the international spread of disease in ways that are commensurate with and restricted to public health risks, and which avoid unnecessary interference with international traffic and trade.23 The new IHR concept is a major paradigm shift, and the document introduces several important innovations. It replaces the old list of 3 diseases with a broader syndromeoriented approach (based on case definitions for health events) that would encourage surveillance for both known and previously unknown infectious diseases. In an important innovation, national core capacity requirements for surveillance and response are enumerated. The concept of a ‘‘public health emergency of international concern’’ (PHEIC), requiring reporting within 24 hours, is introduced and defined. Perhaps most important of all, for the first time a decision instrument has been developed to specify criteria for reporting and response. Although there is a need, of course, for further development of decision criteria and triggers for response, these innovations are a major advance. Implementing the new IHR (2005) will require each nation to have a real-time event monitoring system and strengthened surveillance capabilities.24 There will be significant challenges to implementation of this important initiative, even in the U.S.25 Additionally, each country must fund the program from its own resources, and many will require financial help and incentives.