The need for international surveillance and response to emerging
and re-emerging communicable disease threats to global
public health is now well established. The WHO system for
communicable disease outbreak detection and verification
established in 1997 relies on careful monitoring of formal and
informal sources of information. It is supported by GOARN,
which facilitates the provision of resources for response to international
public health threats related to communicable diseases.
No such system has existed previously for chemical threats.
The awareness of the international community concerning
chemical releases has been heightened by major incidents
such as those in Seveso and Bhopal, the oil spill off the coast
of Spain and terrorist action in the United States of America
on 11 September 2001 (12–15). The development of systems
for the early detection of, and public health response to, chemical
incidents has become a high priority at both national and
international levels.