Coping with bioterrorism

The terror attacks on the World Trade Center in Manhattan in 1993 and the Federal Building in Oklahoma City in 1995, together with the Sarin attack on the Tokyo subway in 1995, have forced upon America an unwanted awareness of its vulnerability to terror attack. So far there have been no biological attacks within the United States, but many feel that this may only be a matter of time. Recently the Institute of Medicine and the National Academy of Sciences have made recommendations for research that would help in managing chemical and biological terror attacks against the civilian community.¹

There are specific problems that are unique to biological attacks. Firstly, whatever the agent, and however it is delivered, there will be time lags between exposure and onset of the first symptoms and the development of the full blown disease. Thus the disease will be dispersed before we become aware that an attack has occurred (assuming no public announcement by the terrorists). Since the population exposed in a large community will approach the health system in many different ways there may be no clumping of cases to trigger awareness of an attack.

Secondly, the early manifestations caused by virtually any of the biological agents will look identical clinically. It is currently impossible to distinguish viral from bacterial disease until a specific organ pathophysiology declares itself, and this will probably be true also for a biological weapon. Moreover, since many of the weapons will be viral, the virulence of the attack weapon will probably be missed until significant morbidity and mortality have occurred. As a result, if there is no announcement of an attack, many patients will become critically ill and die even if the agent is one for which there is a specific diagnostic test and treatment. Conversely, if an attack is announced, medical facilities risk being overwhelmed by the many people who think they may have been exposed.

Thirdly, it is hard to raise money to defend against a problem that has such a low incidence. Moreover, since it is unlikely that the same community will be attacked repeatedly it is difficult to maintain an effective disaster response.

Fourthly, even for those agents that have specific therapy there will be huge problems in delivering it.²,³ For example, though there is an effective vaccine against anthrax, the supplies of vaccine are limited, and no new vaccine is being produced. Anthrax is unique in that if the diagnosis can be made before organ failure the disease can be held in check with high doses of antibiotics while the population at risk is immunised. Although spread of the agent can be predicted to follow air and wind patterns,⁴ tracking its spread will be made harder by the self dispersion of the exposed population before they are aware of being ill. Moreover, even if we had adequate supplies of anthrax vaccine, many citizens might refuse it.

Anthrax introduces another quandary in planning. It is one of the few biological agents that actually has a treatment. Thus terrorists might simply choose an agent less amenable to treatment. Another quandary is involved in any discussion of smallpox. Although eradicated as a worldwide disease, there remain two principal populations of smallpox virus, one in Atlanta and one somewhere in Russia. Only small doses of smallpox vaccine remain,¹ and no agency is creating new vaccine. While vaccination is effective in the first few days after exposure, it is again unlikely that there will be enough vaccine to be effective against a large population attack. Many elderly people were once immunised but so long ago that their effective immunity must be almost non-existent. Smallpox is also unique in being spread by contiguous contact, so it potentially represents a severe and effective weapon. We do not know whether any of the chemotherapeutic antiviral agents would be effective against smallpox, and this was an area of research recommended by the Institute of Medicine report.¹

It has also become apparent that the management of any biological attack must depend on systems already in place for managing new diseases or new epidemics of old diseases. Unfortunately, US public health surveillance systems are not modern, and there has been little thought about how an epidemic might be recognised quickly. Most state public health departments are underfunded and do not have the staff to investigate anything more than a recognised epidemic.

Analysis of the Sarin attack in Tokyo shows that communication between intelligence and law enforcement agencies and health agencies needs to be improved. The medical community was never warned about an impending attack in Tokyo, and doctors learnt about the cause of the problem from another Japanese community that had sustained a Sarin attack a few months earlier.^5–8

Attacks may occur without warning, but there is every reason to think that, given intelligence about potential attacks, a focused and localised response could be achieved. An example would be to warn emergency departments, primary care clinics, and local public health agencies, as well as to build up supplies of any treatment that might require stockpiling, such as antibiotics or vaccine. In light of the above, there is a need for identification technologies that are quick and accurate. Right now, there are none,¹ and it is difficult to envisage where the development is to occur given the lack of opportunity to study these diseases other than theoretically or in the laboratory.

Another weakness in our response is the effective protection of medical teams. People simply cannot work effectively for long in the protective garments that currently exist, and without protection many health team members will themselves become sick or die. There are no good methods of decontamination after chemical, never mind biological, exposure, and how to restrain the spread of a disease that has already started to spread before it produces the first symptoms is a true conundrum.⁹

One consequence of a terror attack is the residual psychological impact on the community. This will include overload of medical facilities by the “worried well,” grief responses felt by survivors,¹⁰ and anger at not being protected. Moreover, the deaths of many adults might produce large numbers of children with no one to care for them, who will overwhelm the community's social agencies.

It is easy to become pessimistic about biological attacks, but the Institute of Medicine committee thought it would be possible to lessen the numbers of casualties and deaths through proper planning, superposition of the disaster teams that already exist, and the creation of special strike teams that could enter an attacked area, bringing supplies of specific therapeutic agents with them. Most of the problems are capable of being solved in part with an infusion of will, money (already promised by the US president), and practice for the unusual and infrequent event. Even if a terror attack is never encountered society will benefit from attempting to solve the problems of a biological attack because we will always be faced by such attacks from nature. The efforts we make to respond will be useful in managing new epidemics or re-emergent infections.