A bioterrorism threat for the birds?

sensible outcome must take note of certain realities.

First, even if details about the research are banned from publication, much has already been made available to a large audience.  This past September, at a conference on influenza held in Malta, Fouchier made a presentation on the mutated virus before some 100 scientists and policy makers. His paper was distributed at the conference. To put a clamp on further dissemination at this point would at best slow its spread.

Second, worries about the newly created virus are based on its virulence and transmissibility in ferrets.  Responses in humans may not be the same as in these animals. Also, since only 600 human cases of bird flu have been identified, effects on this relatively small number may not be representative of what would happen to a larger population. This has prompted Fouchier and other scientists to maintain that the ostensible effects of the virus on humans have been exaggerated.

Third, the steps to enhance the virulence of H5N1 include the specification of five mutations on two genes of the virus. Understanding the process requires expertise on genetic manipulation and knowledge about the location of the mutations. While not beyond the capabilities of a skilled microbiologist, neither is the process a simple or everyday exercise.

Fourth, the appeal of the mutated virus to a terrorist is its presumed transmissibility and lethality to humans.  But these effects remain speculative. Other microorganisms are already appreciated as serviceable biological weapons, among them the agents that cause anthrax, smallpox, and plague. With such known agents, why would a terrorist invest time and resources to acquire a new one with an uncertain payoff? 

This is not to ignore the worst-case possibilities, or that science should never be constrained. A universal consensus holds that some experiments should be prohibited altogether: for example, any that involve the interbreeding of humans and other primates, or experiments on embryos after some level of maturation. But history also offers lessons about more oblique examples.

Constraint was debated in the 1940s and 1950s at the time of development of the atomic and hydrogen bombs, in the 1960s on the permissibility of experiments on human subjects, and in the 1970s over recombinant DNA experiments. In each instance, after varying degrees of hesitation, the work went forward, though with proposed guidelines and limitations.

The most relevant model to the H5N1 challenge was the decision in 1975 by scientists to suspend work in the new field of recombinant DNA research. The moratorium arose from concern that combining DNA from different organisms could create safety risks.  Leading biological scientists held a meeting in Asilomar, California that resulted in guidelines for such research, including the banning of certain experiments. Among those prohibited were the cloning of genes from highly pathogenic organisms. 

Regarding the H5N1 issue, with some reference to the Asilomar example, the logical path is underway. The WHO Global Summit in Geneva will begin the process in mid-February, though deliberations may continue for some time after.  Depending on progress toward clarification of key issues and a consensus on guidelines, the sixty-day moratorium on research may need to be extended.

We may be at the beginning of a new chapter, but it is one in an old book. Based on lessons of the past, research on mutated H5N1 will resume, though with some modest limitations.

Leonard A. Cole, an expert on bioterrorism and on terror medicine, teaches at Rutgers University and the University of Medicine and Dentistry of New Jersey