The New York Times first reported July 7 that the government planned to vaccinate 500,000 healthcare workers who would be first to respond to a bioterrorist attack and treat people infected with smallpox. The CDC's advisory committee on immunization practices -- made up of independent experts -- recommended last month that first responders be vaccinated. At the time, the chair of the committee gave a rough estimate that this could include up to 20,000 people.
Anthony Fauci, director of the National Institute of Allergies and Infectious Diseases, speaking at a meeting on issues surrounding smallpox vaccination, said the committee chair probably said the number flippantly. Fauci said no decision has been set in stone.
D.A. Henderson, principle science adviser to the secretary for the office of public health preparedness, said "there has never been an estimate that I'm aware of," of how many people might be included in the vaccination number. He noted the federal government still is waiting to hear from state health commissioners on the number of healthcare workers that would need to be vaccinated in their state before arriving at a final number.
Fauci told United Press International government officials are still considering the recommendation made by the advisory committee and have not yet reached any conclusions. The ultimate decision will be made by Health and Human Services secretary Tommy Thompson, who will likely arrive at a decision "in a reasonable time," he said.
Some experts have said ring vaccination -- the current policy of the CDC to wait until there is a smallpox attack and then quarantine infected victims and vaccinate their contacts -- will not work. These opponents have called for mass vaccination of the entire population, saying this is the only way to ensure that everyone is protected.
It appears, however, the government is leaning toward vaccinating first responders and maintaining its strategy of ring vaccination. Both Fauci and Henderson said the vaccine has serious side effects, including death, and this has to be balanced against the fact smallpox is not very contagious and thus is likely to be contained by ring vaccination. They also pointed out that this can be adapted and expanded to fit the situation, even to the point of vaccinating the entire population.
The virus is not easily spread via sneezing or coughing, Fauci said. It generally requires close contact between people to spread it. People do not become contagious for a week or two after they are first infected and the vaccine can be given as late as four days after infection and still be effective, he said.
Fauci pointed out before mass vaccination was halted in 1972, more than 20 deaths and hundreds of serious side effects occurred each year due to the vaccine. "This is the least safe human vaccine and it is currently unlicensed (by the FDA)," he said.
Current estimates are one accidental death would occur with every million people who get vaccinated, but Henderson said this may need to be revised. There are more people today than in the 1960s and '70s with certain medical conditions that put them at increased risk of some of the serious side effects of the vaccine, he said. These include increased numbers of children with eczema, people infected with HIV/AIDS and cancer and transplant patients with weakened immune systems.
First-responders should be vaccinated before there is an attack if possible, Henderson said. This is because doctors and nurses who are vaccinated would be required to stop treating patients for a few days because they can shed the virus and possibly infect those who have not been vaccinated, in particular, patients in hospitals who might have weakened immune systems.
Ed Thompson, state health officer of Mississippi and a member of the CDC's advisory committee, said state public health officials are experienced at doling out mass vaccinations -- states have had to vaccinate several thousand people at a time due to outbreaks of diseases such as spinal meningitis, hepatitis and measles -- and they will be quite capable of doing it with a smallpox attack.
Thompson noted, however, many public health officials think developing a specific plan for dealing with smallpox, including plans for vaccinating large numbers of people, should be a priority for each state. He urged states that have not yet formulated such a plan to do so immediately.
State public health officials also oppose mass vaccination of the entire population, Thompson said. A recent survey found the majority of state officials favor utilizing the ring vaccination strategy and vaccinating first-responders prior to an attack.
States officials surveyed also said they think the public does not understand fully the risks associated with the vaccine or smallpox itself. They strongly suggested a widespread educational campaign, which would help people make better-informed decisions.
Whichever vaccination strategy government officials decide to adopt, there is a definite need for a plan to react to a smallpox attack, Fauci said. "It is clear that smallpox is a real bioterrorist threat," he said, adding the Russians produced tons of smallpox in their biological weapons program and "you'd have to be somewhat naïve to think every bit of that has been accounted for."
"The threat of smallpox is small ... but it's not zero," Henderson said. Smallpox is less likely than anthrax to be released, but if it was it could cause a "global catastrophe," he said.