ABSTRACT

Despite the eradication of naturally occurring smallpox, variola virus remains a concern because of the possibility that clandestine stocks of the virus may be in the hands of bioterrorists [4]. The effect of a smallpox virus attack in the human population now would be even more catastrophic than during the last century; vaccination programs were abandoned world-wide around 1976, the prevalence of immunosuppressed populations has grown, and mobility, including intercontinental air travel, has accelerated the pace of viral spread worldwide. It is for these reasons that considerable investment is being made into development of improved countermeasures against smallpox, including new vaccines and antiviral drugs [5].