The revised regulations replace the previous diseasespecifi c framework with one built on timely notifi cation of all events that might constitute a public health emergency of international concern, taking into account the context in which an event occurs (15) . The advantage of this approach is its applicability to existing threats as well as to those that are new and unforeseen. The regulations also recognize the existence of threats to public health outside the infectious disease context, such as those associated with natural disasters, industrial or chemical accidents, and other environmental changes, which might cross international borders.