The recent outbreak of severe acute respiratory syndrome
(SARS) demonstrated to the global public health community
that surveillance does not always meet its primary objective of
providing “information for action” because of several inherent
weaknesses (16). These weaknesses include poor reporting of
events by health care workers, unequal distribution of health resources
and infrastructure (both between and within countries)
and suppression of reporting for fear of sanctions. To address
these weaknesses, the global chemical surveillance system used
both formal and informal information sources, as well as networks
of organizations.