David Heymann

“Technology is a queer thing,” writer and scientist C.P. Snow once observed. “It brings you great gifts with one hand, and stabs you in the back with the other.”

Along those lines, the same technology used to make life-saving vaccines can produce viruses immune to those vaccines. Terrorists can employ improved drug delivery technology and other scientific advances to make their attacks more deadly.

David Heymann, director of the Global Polio Eradication Initiative for the World Health Organization (WHO), and Tara O’Toole, CEO of the University of Pittsburgh Medical Center’s Center for Biosecurity, talked about the two faces of vaccine technology April 12 during Pitt’s “Remembering Polio” scientific symposium commemorating the 50th anniversary of the development of the Salk polio vaccine.

Tara O'Toole

Heymann expressed optimism about eradicating polio worldwide, pointing out that a new polio vaccine is being developed for countries such as India and Egypt, where high population densities have made eradication difficult. “With the development of new vaccines, it will be more than possible to break the back of polio in those areas,” he said. He estimated that in Asia, polio could be eradicated by June. The WHO certifies eradication three years after the last case of polio in a geographic area.

Although the oral polio vaccine (OPV) developed by Albert Sabin is easier to distribute, it does not offer as much protection as Jonas Salk’s intravenous polio vaccine (IPV). Moreover, OPV can convert to a wild-type virus, causing polio outbreaks. There have been four such outbreaks worldwide since 2000. “After wild polio has been eradicated, the continued use of OPV will compromise our goal of a polio-free world,” said Heymann. Therefore, after the eradication of polio, only IPV vaccinations will be used. However, the world must not allow routine immunizations to lapse, he said: “As long as the disease is in one country in the world, it’s a threat to all other countries.”

The biggest challenge in disease eradication is engaging national leaders in the process, he said.

A similar challenge exists in preparing for biological weapons attacks, said O’Toole. Although most people may envision a biological attack as a “lights and sirens” event similar to 9/11, O’Toole emphasized that a terrorist-engineered disease epidemic would be much different, causing long, agonizing months of illness that would strain the social fabric and exacerbate tensions in stricken countries.

A critical problem in such a situation would be lack of information, said O’Toole: People want to know what is going on, how long it will last, and how many people will get sick, and they will panic if their leaders don’t provide answers.

During the “Atlantic Storm” exercise conducted by the Center for Biosecurity in January, delegates from various nations acted as heads of state dealing with an international smallpox outbreak. Failing to find a solution on their own, participants looked to the WHO for answers. They were shocked to learn that the WHO has approximately the budget of a mid-size British hospital and lacks both the funds and personnel to deal with worldwide pandemics.

Bioweapons can cause just as much damage as nuclear weapons and are much cheaper and easier to obtain, according to O’Toole. “Al Qaeda is technically sophisticated and learning fast,” she said. “The question is: Are we going to react appropriately?”

Noting that it is impossible to guard against every potential threat, O’Toole recommended focusing defense efforts against biological and nuclear weapons. International cooperation will be required in developing “health information highways” to speed distribution of information in the event of an attack, new funding schemes, and radically accelerated drug development, she said.

Just as the Salk vaccine resulted from a determined effort to conquer polio, said O’Toole, successfully defending against biological attacks can only come from making that defense a national priority.