July 15, 2003

 

 Though better prepared after 9/11, America still vulnerable to bioterrorism

Posted on June 30, 2003
 

Veterinarians critical to strengthening public health and emergency response plans

As the nation strives to bolster its biosecurity, government and public health officials are recognizing veterinarians as being uniquely qualified to identify several of the biologic agents likely to be used in an attack.

Assessments of the country's vulnerabilities indicate that not only are people at risk of biologic and chemical terrorism, but animal agriculture is also threatened. The nexus between public health and veterinary medicine has never been more apparent.

Any number of bioterrorism scenarios can be envisioned, many of them deadly and frighteningly simple to execute. Aerosolized anthrax discreetly released in a crowded city subway could infect hundreds of commuters without their knowledge. A highly infectious animal disease agent such as the foot-and-mouth virus brought into the country on a cotton swab could cripple the U.S. beef and pork industries.

9/11 fundamentally altered the nation's view of terrorism and dispelled any illusions of security. Most worrying is that a nuclear, chemical, or biologic weapon of mass destruction will be used against targets in America.

Chemical and biologic agents are the ultimate weapons of terror because they have the potential for causing high morbidity and mortality, as well as wreaking political and economic chaos, according to bioterrorism expert Michael Osterholm, PhD, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.

"Many individuals and groups realize the power of a chemical or biologic weapon is not just in the number of people it kills, but also the fear and panic it creates," he said. "There have been several studies done showing that if you released Bacillus anthracis in a large urban area, you could have a similar number of deaths as you'd see with a large nuclear weapon."

Dr. Osterholm has advised Health and Human Services Secretary Tommy Thompson and other government officials on bioterrorism and public health. In his book "Living Terrors: What America Needs to Know to Survive the Coming Bioterrorist Catastrophe," published in 2000, Dr. Osterholm wrote that it wasn't a matter of if an infectious disease will be used to kill U.S. civilians, but when.

It didn't take long for Dr. Osterholm's grim predication to be realized. Days after 9/11, anthrax-tainted letters started arriving at media outlets and the offices of two U.S. senators. In the end, five people were dead from inhalation anthrax, and parts of Washington, D.C., including the Hart Senate Building, had been shut down, for decontamination. Authorities have yet to charge anyone for the attacks.

Concerning public health crises, nothing comes close to bioterrorism, according to Dr. Osterholm. "If you had 50 or 100 cases of anthrax or a few cases of smallpox, the actual response of the community and the kind of impact that would have is far different than if you had a similar number of heart attacks," he explained.

What makes bioterrorism so difficult to combat is there are so many possible perpetrators—from countries that make and provide the agents of destruction to terrorist cells to the lone offender, such as a medical research scientist who uses his skills to harm society rather than help it.

Another complication is that some biologic agents aren't difficult to manufacture. Dr. Osterholm recounted how the Federal Bureau of Investigation reverse-engineered the anthrax powder used in the 2001 terror attacks. Using samples of the highly purified material and working backward, they determined how the anthrax was made, and then created an identical powder.

"Their conclusion was it would cost less than a thousand dollars and (require) someone with a college education only—not an advanced degree—to do that," he said, adding that the materials were readily available.

Given the relative ease of building some types of biologic weapons, they are a kind of "poor man's bomb," according to Dr. Osterholm. "The ability to do this is within the realm of possibility for many groups, from a financial or technical standpoint, where other weapons wouldn't be."

Because America is such a target-rich country, Dr. Osterholm believes the probability of additional bioterrorist attacks, including large-scale assaults involving thousands of people, is high. Still, major steps have been taken in terms of the country's bioterrorism and public health preparedness. He is encouraged by the increasing number of veterinarians serving in senior roles within the public health community.

Their training in infectious diseases that harm humans and animals makes veterinarians an essential component of any emergency response plan. Four of the six deadliest biologic agents identified by the national Centers for Disease Control and Prevention are zoonoses—B anthracis, Yersinia pestis, Francisella tularensis, and filoviruses/arenaviruses. The other two most lethal agents Clostridium botulinum, which causes foodborne botulism, and the orthopoxvirus that causes smallpox.

In his address to the North American Veterinary Conference in January, U.S. Surgeon General Richard Carmona, MD, recognized veterinarians as being critical to the nation's ability to detect and respond to biologic weapons. Since its inception, veterinary medicine has had as its major purpose to protect human health from pathogens often found first in animals, Dr. Carmona observed.

"Of the 1,600 pathogens known to infect humans, about one half are zoonotic," he said. "That puts veterinarians on the front lines of detection of biological weapons of mass destruction."

Dr. Carmona encouraged veterinarians to continue educating themselves about endemic and foreign disease agents that might be used in a biologic attack. "It will be most important for private practitioners to educate their clients as well," he added. "Agricultural producers and even pet owners may be the first Americans to witness an attack of agroterrorism or bioterrorism."

Federal and state agencies have been testing their response to a biologic attack by simulating disease outbreaks. Dr. Thomas McGinn, assistant state veterinarian and head of the North Carolina Agriculture Department's Emergency Programs Division, has helped design bioterrorism simulations for the National Defense University, U.S. Department of Agriculture, and his home state itself. Dr. McGinn is also deputy team leader of AVMA Veterinary Medical Assistance Team 3.

The simulations are a valuable opportunity to measure response plans and capabilities and identify areas where improvements are needed. While he could not discuss the details of the simulations, Dr. McGinn did say that in the exercise conducted in North Carolina, a biologic agent was introduced in multiple locations, and by the time it was diagnosed, the agent had spread to more than half the states.

Early disease detection, rapid diagnostics, and quick response are necessary to counter a biologic attack. One lesson learned from the simulations is that force multiplication—deploying large teams of personnel trained in such fields as decontamination, perimeter control, and mortality management—can help minimize damage.

"Force multiplication is a key thing in a bioterrorist attack," Dr. McGinn said. "You've got to bring a lot of people to bear to stop the spread of a biologic agent very quickly." Team models are being created for groups responding to animal disasters, he added.

Despite massive human and financial resources being dedicated to strengthening homeland security, and the stockpiling of antimicrobial and vaccinating for anthrax and smallpox, America remains vulnerable. Dr. Osterholm says there is no perfect plan to prevent someone from releasing a deadly virus into a large city. What can be done, he said, is to continue taking steps to reduce the impact of such an event.

Dr. Osterholm is quick to caution against complacency. "To say that we've eliminated or even greatly reduced the risk (of a biologic attack) would be a mistake."