individuals—the most familiar example being anthrax. In either case, some agents may persist in the environment, as do anthrax spores, and continue to cause problems long after their release.
In addition to naturally occurring pathogens, biological agents used offensively can be genetically engineered to resist current therapies and evade vaccine-induced immunity. Though it is vital that the molecular mechanisms by which classes of organisms cause disease (pathogenesis) be elucidated in order to understand and counter their effects, this is no simple matter. Preparedness for a biological attack against people, crops, or livestock is complicated by the large number of potential agents, the long incubation periods of some agents, and their potential for secondary transmission.
Biological agents do not need to be weaponized for effective dissemination. Deliberate contamination of food looms as perhaps the easiest method, despite the recent focus on release of these agents as small-particle aerosols or volatile liquids. Moreover, because of its size and complexity, the U.S. food and agriculture system is vulnerable to deliberate attacks, particularly with foreign diseases that do not now occur domestically. Even without actual attack, plausible threats to infect populations or poison the food supply could, in and of themselves, damage the U.S. economy and reduce public confidence in the government’s ability to safeguard health and security.
Recent experiences with the West Nile virus and anthrax spores in the United States, and with foot-and-mouth disease in the United Kingdom, offer practical lessons in human and agricultural outbreak detection, laboratory diagnosis, investigation, and response that might be useful in planning for future attacks involving biological terrorism (Fine and Layton, 2001). The experience with the West Nile virus outbreak highlighted the importance of communication and coordination between responding agencies (U.S. General Accounting Office, 2000). The GAO study noted that although the system worked, there were several obvious places for improvement. A single alert physician at a local hospital initiated the investigation early enough that an effective intervention was possible before the outbreak became widespread, but the investigation subsequently found many other cases, which were either not properly diagnosed or not reported to the health department. The GAO report concluded that much more systematic surveillance and reporting at the local level is needed. Similarly, improved communication among public health agencies, including those dealing with animal health, is needed. Increased laboratory capacity will also be important to an efficient and effective response to disease outbreaks (at first only one public health laboratory in the country was equipped to diagnose West Nile virus) (IOM, 2002). Moreover, these events raise vexing concerns about how many outbreaks could be managed at one time.
The attacks of September 11, 2001, and the intentional release of anthrax spores shortly afterward also revealed vulnerabilities that are the results of long-term declines in the nation’s public health and agricultural infrastructures. The