Expert Panel Rejects Mass Inoculations
By David Brown
Washington Post Staff Writer
Friday, June 21, 2002; Page A01
ATLANTA, June 20 -- A panel of scientific experts that advises the federal government recommended yesterday that a small number of health care workers in each state -- perhaps 20,000 Americans in all -- be vaccinated against smallpox to protect them in the event of an outbreak.
The advice, if accepted by the Bush administration, would expand the use of the vaccine for the first time in nearly 30 years. But it represents the most limited of several options the panel considered for incorporating smallpox vaccination into the country's defense against biological terrorism.
The choice reflects the panel's belief that the risk of an attack employing smallpox virus is too small to justify the many complications that would arise from widespread vaccination.
Currently, only scientists who handle the virus are vaccinated. The last human case of smallpox occurred in 1978, and the microbe is known to exist only in a few laboratory freezers. Some experts believe samples of the virus may have gotten into the hands of bioterrorists or hostile governments.
The decision also affirms a belief that the strategy used to eradicate smallpox in the 1970s would work in the event of a bioterror attack. That strategy, called surveillance-and-containment, requires that people exposed to smallpox virus, and their immediate contacts, be vaccinated, observed and quarantined if they become ill. This approach, also known as "ring vaccination," doesn't rely on full-scale vaccination of a population, either before or after an outbreak.
"We had to base our decisions on what we were told, which is that the risk [of attack] is low," said Natalie J. Smith, a California state public health official and a member of the 15-member Advisory Committee on Immunization Practices. "We will reconsider our decision if we get information that the risk is changing."
The ACIP is made up of academic physicians and public health officials appointed by the Centers for Disease Control and Prevention. Its advice carries great weight and is usually followed.
In a statement, Health and Human Services Secretary Tommy G. Thompson said he will "now review the recommendation with experts . . . as the administration works toward a policy on the smallpox vaccine."
Under the recommendation, each state would designate at least one "smallpox response team" composed of physicians, epidemiologists, investigators, lab technicians, nurses and vaccinators. A few law enforcement officers (possibly from the FBI or state police agencies) might also be included in this group. In general, though, paramedics, police officers, firefighters and other "first responders" would not be vaccinated. Each state would also pick one or more hospital to be a referral center for possible cases of smallpox. At each site, a pre-designated group of caregivers -- including possibly clerks and technicians -- would be vaccinated and expected to care for initial cases.
In all cases, vaccination would be voluntary. Although many states are already putting together such teams, it's unlikely vaccination would begin before October. That's because many legal and procedural decisions must be made, including who will pay damages to people harmed by the vaccine.
A recent poll found that 60 percent of adults would take smallpox vaccine if offered it. Although the committee considered public demand -- and the argument that citizens, not the government, should make the final risk-vs.-benefit calculation -- this view was ultimately rejected.
"This is a public health decision. There are many issues in the past where the public health interest does not jibe with the personal health interest," said John F. Modlin, a professor at Dartmouth Medical School and chairman of ACIP.
Smallpox vaccine is a live virus, vaccinia, which infects a person and sets up an immune response that protects against smallpox, a closely related microbe. It causes more serious and more frequent complications than vaccines used against other diseases.
Even with careful screening of people at high risk of vaccine complications -- AIDS patients, recipients of organ transplants and others with weakened immunity -- smallpox vaccination would probably cause at least one death per million people vaccinated. A larger number of people would become seriously but not fatally ill, although some would have permanent disabilities.
A newly vaccinated person can transmit vaccinia to other people for a brief period. The likelihood of such spread -- and the fact the vaccine is technically "experimental" and must be given only after extensive counseling -- weighed heavily in the committee's decision.
"You can transmit it to people who haven't consented," Smith said.
Proponents of wider use of the vaccine say these risks are overpowered by the chance that a smallpox outbreak could get out of control if it began in multiple places or with a large number of initial victims.
"I think ring containment in a terrorist situation has been thoroughly discredited . . . and that has not been recognized by CDC," said William J. Bicknell, a physician at the Boston University School of Public Health who was the Massachusetts health commissioner in the 1970s.
He cited a mathematical model constructed by a Yale University researcher that predicted an attack that began with 1,000 infections would lead to nearly 100,000 deaths in three months if addressed through ring containment, but fewer than 1,000 deaths if there was mass vaccination immediately after the first cases were identified. That model was one of several -- and by far the darkest -- presented to the committee at several meetings in recent weeks. People who believe it say it argues strongly for a policy of vaccination now, before any cases occur.
© 2002 The Washington Post Company