By Mike Field

During the influenza pandemic of 1918, health officials believed that wearing gauze face masks could interrupt the transmission of the disease. Many localities passed legislation requiring public masking, but ultimately, the exercise was of doubtful benefit. Gauze alone cannot filter viruses. Largely unchecked, the disease ran its course. More than 600,000 Americans died. Globally, up to 20 million perished.

Almost 90 years later, the prospect of such widescale death and suffering seems remote. "But you have to keep in mind that the flu virus of 1918 was fatal in only about 2 to 3 percent of all cases," says Gigi Kwik, PhD, a fellow with the Johns Hopkins Center for Civilian Biodefense Strategies. "Smallpox, by contrast, is typically fatal about 25 to 35 percent of the time." The United States stopped vaccinating for smallpox in 1972; currently, it has about 15 million doses of the smallpox vaccine on hand to safeguard a population of almost 300 million. Since the World Health Organization declared smallpox eradicated in 1980, the doses of vaccine on hand seemed, until recently, more than adequate. But with the revelation in the 1990s that the Soviet Union had produced tons of smallpox for an illegal bioweapons program — and the uncertainty of whether any of those materials were eventually acquired by terrorists — those 15 million doses of vaccine have lately begun to seem like just so many gauze masks.

Yet the outlook is not entirely bleak. For each of the biological weapons considered by experts to be the most serious threats to America — anthrax, botulinum toxin, plague, smallpox, or tularemia — modern medicine has some effective means of responding, be it by vaccination, antibiotic, or antitoxin. And despite years of neglect of the nation's public health infrastructure, and an ongoing crisis in the delivery of health care, the U.S. still has one of the world's most comprehensive and sophisticated systems of medical care. "I'd say [in the event of a smallpox outbreak] we'd be OK in the long run," says Kwik. "A lot of other countries, by contrast, would do quite poorly."

In recent years, the government has established national pharmaceutical stockpiles in hidden, secure locations as part of a coordinated effort to prepare for the possibility of a biological warfare attack. The sites contain antibiotics, medical and surgical equipment, gloves, masks, and other supplies useful in a widescale medical crisis. The system had its first test on Sept. 11, and authorities report medical supplies were delivered to Ground Zero in New York within seven hours of the attacks.

Defending Against Bioweapons:
The Latest Vaccines and Antibiotics

Anthrax — The anthrax bacterium can be stopped by the prompt administration of antibiotics, including ciprofloxacin and doxycycline. An anthrax vaccine requiring a series of six shots over a period of weeks has been licensed since 1970 but is currently in limited supply in the U.S.

Botulism — Licensed botulinum antitoxin is available only from the CDC via state and local health departments. An investigational botulinum toxoid has been used to provide immunity against botulinum toxin over the past 30 years, but widescale immunizations are currently considered impractical.

Plague — A U.S. licensed vaccine exists and in a pre-exposure setting appears to have some efficacy in preventing or ameliorating bubonic disease, but not against inhalationally acquired pneumonic plague. Immediate administration of antibiotics such as streptomycin or doxycycline as treatment or prophylaxis would significantly reduce the mortality of the disease.

Smallpox — There is no known treatment to fight the disease once it begins; and essentially no one in the U.S. has been vaccinated during the past 29 years. Immunity acquired decades ago wanes substantially with time. Infected individuals can be inoculated with the vaccine as long as 3 or 4 days after their smallpox exposure and still receive protection against death from smallpox. Currently, there are about 15 million doses of the vaccine available in the U.S., and another 60 million worldwide.

Tularemia — With prompt antibiotic treatment, the most recent mortality rates in the U.S. have been 2 percent. A live-attenuated tularemia vaccine has been used to protect laboratory personnel, but given the short incubation period of the disease, and incomplete protection of current vaccines against inhalational tularemia, vaccination is not recommended for post-exposure prophylaxis.

Source: Johns Hopkins Center for Civilian Biodefense Strategies

Even so, there is some concern that the amount of supplies and system organization are inadequate to respond to a biological attack of any magnitude. "Antibiotics and vaccines alone are not enough," says Thomas Inglesby, MD, deputy director of the School's Center for Civilian Biodefense Strategies. An infectious disease specialist who holds an assistant professorship in the School of Medicine's Division of Infectious Diseases, Inglesby cites the need to beef up state, city, and local health departments, increase national disease surveillance capacity, address the lack of "surge capacity" in U.S. hospitals, improve community response plans, and more thoroughly plan for sudden, widespread medical catastrophes.

"A national biomedical research and development program to address the nation's greatest infectious disease vulnerabilities is also an imperative," says Inglesby. "We want to have the diagnostic tools to be able to say if a person is sick or not sick, and a public health system of tracking disease as it evolves and containing the spread of disease."

An analysis by the Office of Technology Assessment of the U.S. Congress estimated that as many as 3 million deaths could occur following the release of 100 kilograms of aerosolized anthrax over Washington, D.C., making such an attack as lethal as a hydrogen bomb. Prompt detection and immediate administration of the proper antibiotics could save many or even most of those lives. But the logistics of such an effort, including the delivery and distribution of 5 or 6 million doses of antibiotics, remain daunting. Says Inglesby: "If we don't have rapid systems of distribution, people won't get the antibiotics they need. We need a medical care system capable of handling sick people in greater numbers than we've ever seen before."

A problem already apparent to many is simply the shortage of necessary medicines. The anthrax mail attacks have prodded the government to significantly increase the scale and scope of its pharmaceutical stockpiles. But even that effort faces huge challenges. "You can't go from zero to 60 in five seconds," is how Don Burke, MD, director of the School's Center for Immunization Research, describes the government's recent decision to increase its stockpile of smallpox vaccines from 15 million to 300 million doses. "The current model in treating an outbreak of smallpox is to try to create a ring of immunizations around anyone known to be infected," says Burke, in explaining how smallpox was eventually quarantined and eradicated.

But a model that works for only a handful of infections in remote areas of developing countries may prove inadequate to the challenge of many hundreds, or even thousands, of infections in a highly mobile society. In that situation, it could rapidly become necessary to vaccinate many millions — perhaps even the entire nation. "We don't have any experience in large-scale immunizations of that nature," says Burke, a professor of International Health. "One of the basic questions is just who are we going to get to give all these shots? We'd probably have to very quickly start to look outside the classic health care delivery system for answers."

Researchers are quick to point out that none of the problems associated with the sudden and unexpected widescale infection of populations are insurmountable. What is needed, they say, is planning and the political will to prepare adequately for a future most people would rather not consider. "There are many things to do," Inglesby says. "This is not insoluble, it's not a lost cause, but [the answers] are not necessarily easy or cheap. The problem will not go away when the anthrax mailings are over or when the war in Afghanistan is over."

All agree that a significant change is in order for American health policy. "We spend remarkably little of our public health dollars on vaccination in particular and prevention in general," says Burke of the situation prior to Sept. 11. "The total global annual market for all vaccines is about $3 billion. But every year, we spend $5 billion on Viagra. That should tell us something."

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