What is the future of anthrax? Do we face an escalating epidemic of ever more infections and a future life of fear, disease and death? Certainly not.
I would like to outline the reasons that indicate that anthrax is not the ultimate doomsday threat. My arguments, however, should not be taken as reasons for complacency. What is needed is serious concern without hysteria, prudent action without panic.
First, we know that a bacteria, not a virus, causes anthrax. Bacterial diseases are much easier to treat because they are sensitive to many antibiotics and good vaccines can be prepared against the causative agent — witness the successful control of bacterial killers such as typhoid, pneumonia and hemophilus.
Second, while we know relatively little about the anthrax organism, mainly because it has not been a prevalent human pathogen in recent times, the organism is a member of the genus Bacillus. Microbiologists have studied a close relative of anthrax, the harmless hay bacillus, for over 50 years. Thus, we know much about the properties of this group of organisms and about the biology of spores. We know how these bacteria grow, how they transform to spore form, and what antibiotics are useful in controlling them.
Third, new studies reported in the past six months point the way to the design of drugs which may block or inactivate the lethal factor, a protein, synthesized by the anthrax organism. Such drugs might even treat advanced cases that may be no longer sensitive to antibiotics.
Fourth, immunization against anthrax has been spectacularly successful in nearly ridding the world of its threat as a veterinary scourge. Indeed, the success of anthrax vaccination of sheep at the French town of Pouilly-le-Fort in 1881 consolidated the reputation of the chemist, Louis Pasteur, as a great leader in medical research. Vaccines for use in humans have been used with demonstrated efficacy for over 40 years in high-risk populations. While the existing vaccines have shortcomings, the possibility of vaccination has been proven, and it is only a matter of time and effort — code words for money and resolve — to develop much better vaccines.
Fifth and finally, although the most dangerous form of human anthrax is acquired by inhaling fine particles containing anthrax spores, once the spores settle out of the air, there seems little likelihood of infection. In past epidemics, the case rate dropped to zero after about six weeks, even though the spores remained in the environment and no specific decontamination occurred. In experiments by the U.S. military, re-aerosolization of spores in dirt was difficult if not impossible.
The scientific knowledge of anthrax, its microbiology, its epidemiology and its immunology, suggests that we can be confident that, if necessary, we can control this organism, we can develop improved therapy for the human illnesses it causes, and we can render it relatively harmless.
That we have not yet done so is only because we have not judged it a sufficiently serious threat to warrant such an investment of our national resources. Perhaps now is the time to do so.
William Summers is a professor of therapeutic radiology in the Yale Medical School, a professor in the Molecular Biochemistry and Biophysics Department, and a lecturer in the History Department.