Update: Detection of West Nile virus in blood donations--United States, 2003.

should educate health-care providers to recognize unusual illnesses that might indicate release of a chemical agent. Strategies for responding to intentional chemical releases include (1) providing information or reminders to health-care providers and clinical laboratories; (2) encouraging reporting of acute poisonings to local poison control centers, which can guide patient management and facilitate notification of the proper health agencies, and to the local or state health department; (3) initiating surveillance for incidents that potentially involve the covert release of a chemical agent; (4) implementing the capacity to receive and investigate any report of such an event; (5) implementing appropriate protocols, including potentially accessing the Laboratory Response Network for Bioterrorism, to collect and transport specimens and to store them appropriately before laboratory analysis; (6) reporting immediately to CDC and local law enforcement if the results of an investigation suggest the intentional release of a chemical agent; and (7) requesting CDC assistance when necessary. To begin developing national surveillance capabilities for detecting chemical-release–related illnesses, CDC is collaborating with the American Association of Poison Control Centers to use its Toxic Exposure Surveillance System to identify index cases, evolving patterns, or emerging clusters of hazardous exposures. Identification of early markers for chemical releases (e.g., characteristic symptom complexes, temporal and regional increases in hospitalizations, or sudden increases in case frequency or severity) will enable public health authorities to respond quickly and appropriately to an intentional chemical release. CDC materials for emergency and health-care personnel, including a list of chemical agents and biologic toxins and their expected clinical syndromes, are available at http://www.bt.cdc.gov/agent /agentlistchem.asp. Additional information about responding to chemical attacks is available from the U.S. Army Medical Research and Materiel Command at http://www.biomedtraining.org /progmat.htm, the U.S. Army Medical Research Institute of Chemical Defense at http://ccc.apgea.army.mil, and CDC and the Agency for Toxic Substances and Disease Registry at http: //www.atsdr.cdc.gov/mhmi.html.