ith the memory of September 11 seared in our consciousness and terrorism constantly on our minds, it is not impossible to imagine a biological attack on this country. Let me describe for you a hypothetical scenario that could have followed 9/11 were a biological agent released that was transmissible. On September 12, the first case of an outbreak would be documented; a week later 6,674 cases would be recorded; in another week there would be 12,504 cases and 727 deaths. In six months, a quarter of the US population would be infected, and 4 percent would die. Regrettably, this scenario is not purely hypothetical nor is it related to terrorism: these are the precise figures of the outbreak of influenza at Camp Devens, Mass., in 1918. Within six months, 20-40 million people around the world perished from the flu, more than the number that died in the four years of World War I.

The figures described above make it clear that we have more to fear than bioterrorism alone. In 1991, 17 cases of anthrax and five anthrax-related deaths occurred in this country. In that same year, there were 20,000 deaths and 100,000 hospitalizations in the US due to influenza. An additional 40,000 people succumbed to pneumonia. Yet in contrast to anthrax and smallpox, we currently have safe and effective vaccines against influenza and pneumococcal pneumonia, which could reduce those figures dramatically. But what we don't have is a public health infrastructure that is able to provide these vaccines to those who need them. Infectious diseases do not respect national boundaries, and it is impossible to predict the natural emergence and spread of infectious diseases any more than it is to predict infections introduced by terrorists. Our challenge is to develop public health preparedness that can provide protection from both.

Of all the threats to the security of this country, bioterrorism may well be the most menacing, since it requires only a few individuals with specialized scientific skills and access to a laboratory to produce lethal biological agents. In contrast to nuclear weapons, which require very large and sophisticated equipment, biological terror operations remain elusive in large part because deadly microbes can be manufactured with equipment that military experts refer to as "dual use"--ordinary commercial catalogue items like fermentors and milling machines that are legitimately used to produce pharmaceuticals, vaccines, cheese, and beer. This makes producing biological agents relatively easy (although their dissemination is not trivial) and predicting bioterrorism attacks extremely difficult.

September 11 and the subsequent anthrax attacks revealed the vulnerability to terrorism of an open society. They particularly revealed the vulnerability of a public health system caused by the long deterioration of this country's public health infrastructure. The current administration and Congress have dedicated significant new funds that would establish many important mechanisms to prepare for and respond to bioterrorism. I was privileged to serve as co-chair, with Joshua Lederberg, of the National Academy of Science's Panel on Countering Bioterrorism and as a member of the parent committee that sought to provide a roadmap of how science and technology can serve to make this nation safer.1 There is an urgent need for research to understand the pathogenesis of previously neglected microbial agents that can be exploited by terrorists and how our immune responses can protect against them. New opportunities for research afforded by the deciphering of the human genome--and the genomes of many microbial pathogens--could allow us to identify possible unique targets for drug design that could selectively disrupt vital processes in the pathogens without damaging our own cells. Unprecedented possibilities exist for developing new and sophisticated diagnostics that could permit very early detection of infections or outbreaks.

Yet too narrow a focus on bioterrorism would squander a unique opportunity to redefine the concept of "dual use" for strengthening the public health system in this country. We need a public health system capable not only of responding to terrorism and catastrophes, which we hope will be rare events, but to the continuing struggle to prevent and prepare for a multiplicity of threats to our health. Stockpiling of drugs and specific vaccines is clearly essential but of limited use if, as we hope, threats are not forthcoming. In contrast, one of the great contributions that schools of public health can make is training our public health workforce, of whom fewer than half currently have any advanced training in public health, let alone in the specialized issues associated with terrorism and health communication. The front line against bioterrorism now must include trained personnel in police and fire departments, postal workers, and teachers, as well as health professionals, which implies a continuing need to provide better and broader education and training in public health preparedness. We are most appreciative that the Centers for Disease Control and Prevention designated the Harvard School of Public Health as a National Preparedness Center, and we look forward to expanding the School's Internet-based training programs to develop training modules in the broad areas of preparing for and responding to terrorism. The paradigm at the basis of an effective response to any form of terrorism is the classic public health model: surveillance, prevention, response, recovery, and ascertainment.

How can this country create a more integrated and effective public health system to deliver vaccines against influenza and pneumococcal pneumonia, as well as vaccines against anthrax or smallpox if necessary--and deal with the daily mission of preventing major threats to the public's health, from HIV and cancer to obesity and diabetes? Every major city and county should have a modern computerized system to facilitate informed communication, to share the best information on health risks available with the public. Larger cities need to experiment with systems for detecting significant changes in emergency room patterns or unexpected demands for pharmaceuticals that would allow early warning not only of unusual agents, but also the beginning of the influenza season or potential outbreaks of foodborne illnesses, where early action could save many lives. We need to support promising research to explore the possibility that pathogens imprint specific "signatures," or patterns of specific gene expression, in the infected host that could discriminate true infection from terror or fear--thus freeing up health personnel in the event of a bioterrorist attack to tend to those truly in need. These signatures may even allow a good guess about the nature of the microbe long before it can be identified directly. We also need a Public Health Reserve Corps of people in local health departments, laboratories, universities, schools, and hospitals that can provide the surge capacity required in the case of a terrorist attack or any health emergency.

As a nation whose public health capabilities have been stretched to the limit with a few cases of anthrax, we need to recognize the need for investing real resources in people, professional training, communications, local public health departments and labs, and great research institutions, including our schools of public health and medicine. The "dual use" of our resources, not only to guard against the threats of bioterrorism and catastrophes, but to protect against the many other "clear and present dangers" to health as well--infectious diseases, carcinogens and environmental toxins, unnecessary use of antibiotics, unhealthy foods, tobacco, and injuries--will be the best investment we can make to protect the public's health.

Barry R. Bloom
Dean, Harvard School of Public Health

1. National Academy of Sciences. Making the Nation Safer: The Role of Science and Technology in Countering Terrorism. National Academy Press, Washington, DC, 2001.