But doctors said that just because it may be possible to inoculate everyone against the disease, it may not be prudent to do so unless smallpox actually reappears or there is a valid threat, doctors said.
"In my opinion, we should make enough vaccine to inoculate everybody in the United States and we should be prepared to inoculate everyone," said Dr. Robert Belshe, professor of epidemiology at St. Louis University School of Medicine in Missouri, "but not actually implement that plan until there were a real threat or real exposure."
In experiments to test the viability of some of the stores of vaccine, Belshe and colleagues inoculated nearly 700 people. The researchers used smallpox vaccine that had been stored for a generation and found that even diluted one-to-five times or one-to-10 times there was at least a 97 percent "take" of the vaccine, leaving the telltale scar that was ubiquitous before smallpox was declared eradicated in 1979.
Belshe performed the tests using doses from a 15 million-dose dry vaccine stockpile. He said the discovery of another 70 to 90 million liquid doses of the vaccine in pharmaceutical company freezers was good news for those concerned about having enough vaccine to go around. "We don't know the characteristics of the frozen vaccine," Belshe said, "but we do know that the smallpox vaccine appears to be very, very stable."
Belshe's study will appear April 25, along with several other commentaries and letters dealing with several aspects of a possible smallpox outbreak, in the prestigious New England Journal of Medicine. The articles were made available early, said journal editor-in-chief, Dr. Jeffrey Drazen, "because of the possible public health implications."
Those implications, said Dr. Edward Campion, senior deputy editor of the Boston-based journal, include the risk of complications -- even deaths -- from a widespread vaccine effort.
"Everyone should understand the fact that with a widespread vaccination program there are going to be a significant number of side effects," Campion told United Press International. "It is not a benign vaccine in some people with skin conditions and others with compromised immunity -- and in some otherwise healthy individuals."
Campion said the estimates from several sources are that if everyone in the United States were to be inoculated against smallpox as many as 200-300 deaths could occur from complications. He said that people who suggest widespread inoculation should consider "the unpredictability of the public's response to seeing people dying of the vaccination and how that could effect the confidence of the public in other vaccination programs."
One of the journal articles shows graphic, disturbing images of a patient with a skin condition who developed horrific complications from the vaccine. The patient recovered, but suffered deep, permanent scarring.
On the other hand, Dr. Murray Dworetzky, a clinical professor of medicine at the Weill Medical College at the Cornell University, New York, described his experiences in Japan treating patients with smallpox just after World War II, and watching eight patients die of the disease.
Dworetsky said that led him to vaccinate his patients with "almost religious zeal" when he went into private practice. However, he said the last patients he inoculated against the disease were in the late 1960s. Despite seeing the horrors of the disease, "it would be a real tough call," to perform widespread vaccinations, he said.
For Dr. William Bicknell, professor and chairman emeritus of the department of international health at Boston University, that call is to allow voluntary, widespread vaccination against smallpox. In a commentary in the journal, Bicknell argued that by inoculating the population, the United States would perform a preemptive strike against the use of smallpox as a weapon.
In addition, he wrote, "Post-exposure containment of a terrorist-induced smallpox outbreak is unlikely to be successful. Widespread, voluntary vaccination before exposure will greatly reduce the number of victims, if an attack occurs."
In an editorial, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in Bethesda, Md., said that the differing opinions on what should be done deserve an "open, transparent public discussion so that everyone is aware of what the policies are and how they were determined.
"The final decision on a vaccination program," Fauci told UPI, "should be made by public health officials, but the public should understand the rationale behind those decisions. And it is possible that public responses could influence those public health policies."