The emerging threat of bioterrorism.

The threat of bioterrorism focuses attentionon overall preparedness to address thechallenges posed by new and reemerginginfectious diseases. Bioterrorism scenariosillustrate the diversity of disciplines andperspectives required to confront these threats,whether naturally occurring or purposelycaused. The need to strengthen existing anddevelop new partnerships is clear.Since late 1992, a number of large, complexoutbreaks have occurred in the United States.These include the epidemic of over 400,000 casesof waterborne cryptosporidiosis in Milwaukee,the outbreak of severe, unexplained acuterespiratory disease now known as hantaviruspulmonary syndrome in the Spring of 1993, thenationwide foodborne salmonellosis outbreakcaused by contaminated ice cream thataccounted for an estimated 250,000 cases in thefall of 1994, and the increasing problems posedby antimicrobial-resistant organisms in commu-nity and health-care settings. Epidemics ofplague in India, Ebola hemorrhagic fever inCentral Africa, avian (H5N1) influenza in HongKong, Hendra virus infection in Australia, andNipah virus infection recently in Malaysia andSingapore required an international response.During the hantavirus, plague, and Ebolainvestigations, concerns regarding the possibil-ity of bioterrorism were raised early in theinvestigations, though these concerns were notsupported by subsequent findings.Investigating these outbreaks in collabora-tion with local, national, and internationalpartners has provided a number of importantlessons, which are reinforced by the threat ofbioterrorism. We must avoid complacency andstress preparedness through careful planningand testing of emergency response plans. Thereis a critical need to strengthen surveillancesystems and epidemiologic and laboratorycapacity in clinical and public health settings.The outbreaks have illustrated disruptions oftravel and commerce and potential threats tonational security. The complications of naturallyoccurring, complex epidemics underline theglobal implications of local problems. Theselessons are directly relevant to the threat ofbioterrorism. The challenges of recognizingdisease resulting from the clandestine release ofan infectious agent are considerable, given thepotential for geographic dispersion of the agent(through travel) during the incubation period.The public health approach to bioterrorism mustbegin with the development of local and stateplans formulated collaboratively by the publichealth, emergency response, and law enforce-ment communities, which must work togetherclosely in this phase if an epidemic is to bedetected in a timely manner, which is critical toits appropriate management. Local healthdepartments and health-care workers will be onthe front lines in detection and response.Infection control practitioners, emergency de-partment personnel, microbiologists, first re-sponders, emergency management personnel,and local, state, and federal law enforcementpersonnel will play vital roles and must engagewith each other during the planning stage. Closecollaboration between the clinical and publichealth communities will also be critical.From a public health perspective, timelysurveillance, clinician awareness of syndromespotentially resulting from bioterrorism, epide-miologic investigation capacity, laboratorydiagnostic capacity in both clinical and publichealth laboratory settings, and the ability torapidly communicate critical information at thelocal level to those who have a need to know andto manage public communication through themedia will be vital. In addition, ensuring thetimely availability of an adequate supply ofantimicrobial drugs, antitoxins, and vaccines is aformidable challenge. Deployment and adminis-tration of stockpiled components to thoseaffected or at greatest risk are also critical.James M. HughesCenters for Disease Control and Prevention, Atlanta, Georgia, USA