SMALLPOX AND BIOLOGICAL WARFARE

The first biological weapon

Smallpox has the distinction of being the first biological agent used against an enemy in war times. During the French and Indian war (1754-1763), Lord Jeffrey Amherst served as commanding general of the British forces, leading the British to victory against the French. The Ottawa Indians’ continued hostilities toward the British led to the measures suggested by Colonel Henry Bouquet in 1763 to “try to inoculate the Indians by means of blankets that may fall in their hands, taking care however not to get the disease myself.” Amherst officially approved the strategy, replying in a letter to Bouquet, “You will do well to try to inoculate the Indians by means of blankets, as well as to try every other method that can serve to extirpate this execrable race.” There were reports of a smallpox epidemic the following spring among the Indians after blankets and handkerchiefs were distributed to them at Fort Pitt (http://www.nativeweb.org/pages/legal/amherst/lord_jeff.html).

A modern threat

Much of the literature in recent years speaks of smallpox in the past tense. With the eradication of the disease in 1980, and variola virus research stocks restricted to two labs, the CDC and a lab in Koltsovo, Russia, no one imagined that smallpox would again pose a threat to humanity. However, Henderson et al. (1999) report that since that time a former Soviet bioweapons program deputy director revealed that in 1980 the Soviets undertook a program to weaponize smallpox for use in missiles. They were successful in this endeavor, and because of the economic crisis in Russia, there are reasons to fear that the technology could be bought by others seeking to commit acts of terror.

The events of September 11, 2001, have heightened this fear. Since the smallpox vaccination program was discontinued after eradication of the disease, much of the population is now vulnerable to infection. Only laboratory workers have continued to receive vaccinations, since the risks associated with the vaccine were deemed unacceptable for the general public. Furthermore, vaccination does not provide lifetime immunity; protection beyond 10 years is questionable, according to the WHO.

Apprehension about potential use of smallpox as a bioweapon led to concerns about the amount of vaccine available. In early 2002 the CDC undertook a study to test their vaccine stocks for effectiveness after dilution. Our labs, which work with vaccinia virus, were included in this study. A few of us had received the vaccine prior to eradication, and a subsequent “booster” in 1989 since we handle live vaccinia. However, since vaccination was not mandatory, none of the young graduate students had ever received the vaccine. The diluted vaccines administered were all successful, as evidenced by the various vaccination site lesions we endured, and no one experienced any adverse reactions. Results of this study indicate that a 1:10 dilution of the vaccine retains its efficacy. Frey et al. (2002), in a larger study, report comparable success rates (97.1 to 99.2%) using 1:5 and 1:10 dilutions of the vaccine.

Since those studies, additional measures have been implemented to protect certain segments of the population in the event of terrorism. On December 13, 2002, President Bush announced that volunteer Smallpox Response Teams would be formed to care for citizens should a smallpox attack occur. Team members, along with health care workers, military personnel, and certain other civilians at risk would receive vaccinations. At that time it was also announced that there is now enough vaccine in the United States to vaccinate all of its citizens. However, the future of smallpox as a biological weapon – and as a disease we must once again confront in the population - remains to be seen.

Addendum: On March 25, 2003, the CDC issued a statement recommending that people with a history of heart disease should not be vaccinated against smallpox at this time. This came in the wake of several cases of heart problems after vaccine administration. Two of these resulted in death. Dr.Julie Gerberding, CDC director, in discussing the safety of the vaccine, said, "We promised to closely monitor this program and to put safety first, so we are exercising exceptional caution. If our investigation shows this precautionary measure should become permanent or the need for other changes or enhancement in the civilian smallpox vaccination program, we will take immediate action. We continue to believe that it is important and necessary to vaccinate health care workers to prepare our nation in the event we have to respond to a smallpox outbreak.”

Return home