The threat of bioterrorism has apparently convinced the Bush administration that it should retain the nation's stock of smallpox virus - one of only two official repositories for smallpox samples in the world.

The administration argued that the samples may be needed to help develop new drug treatments and vaccines against the disease. The decision is a sensible response to the small but frightening risk that a rogue nation or terrorist group might obtain the virus and unleash it.

Smallpox was eradicated as a disease more than two decades ago, and all remaining stocks of the virus were supposed to be transferred to two official repositories designated by the World Health Organization, one in Russia and one in the United States.

Debate then ensued over whether even these stocks should be destroyed - to lessen the chance of smallpox escaping again and to set a moral example that even possession of smallpox samples violated global norms. The stumbling block has been intelligence reports that North Korea and Iraq may have retained clandestine stocks for military use.

Some scientists who believe that the remaining samples should be destroyed point out that new vaccines and antiviral drugs can be developed without them, by testing against related viruses.

But the smallpox samples would clearly have some value for these purposes. Indeed, the prestigious Institute of Medicine concluded that the most compelling reason for retention would be to develop antiviral drugs or novel vaccines.

The institute's expert panel made no judgment on whether the stocks should be retained or destroyed. But at a time when bioterrorism has become disturbingly real, it seems wise to err on the side of retention.

New York Times November 16, 2001