OAKLAND, Calif. -- At the Oakland Medical Center this Wednesday (Oct. 16), volunteer adults between 32 and 70 years old are being re-vaccinated against smallpox in a study that will test the effectiveness of different dilutions of smallpox vaccine. Kaiser Permanente's Vaccine Study Center is the lead center in a consortium evaluating the effectiveness of the vaccines on adults who were inoculated against smallpox as children more than three decades ago.
Vaccine Study Center co-director Dr. Steve Black leads the research at the Oakland site in a consortium which also includes Stanford University Medical Center in Palo Alto, Calif.
"Our earlier trial this past summer showed that the Dryvax vaccine and the rediscovered vaccine stock at Aventis Pasteur were both effective when diluted in people who had never received a prior vaccination," says Black. "In light of increasing concerns about vaccinating as many people as possible against a possible bioterrorist attack, I'm glad we're able to learn how effective these decades-old vaccines still are."
Routine smallpox vaccination ended in the United States in 1971. Ten years later, the world was declared "smallpox-free," and routine vaccination stopped worldwide.
"The key questions we're studying are, does the vaccine we have from 30 years ago still produce a protective response in people who have already received the smallpox vaccine, and can we dilute it to make a greater supply available to the U.S. population?" said Cornelia Dekker, MD, associate professor of pediatrics at the Stanford University School of Medicine and the medical director of the Stanford-Lucile Packard Children's Hospital Vaccine Program. "The idea is that the more we can safely dilute this vaccine and still have it be effective, the more doses we can have available if we need them." Stanford has formed a partnership with Kaiser to serve as an additional test site for the trial, which is the largest of a handful of recent trials to study the safety and effectiveness of the smallpox vaccine after a 30-year hiatus.
Concerns about the disease re-ignited with last fall's bioterrorist anthrax cases in Florida, Washington, D.C. and New York. There are stores of smallpox kept in a few places around the world, and the highly contagious disease has often been named a likely candidate for biowarfare.
Most Americans over the age of 35 were vaccinated against the disease as children, but it's not clear that those who received smallpox vaccinations prior to 1971 still have any immunity or how they would respond to re-vaccination.
About 100 healthy people between the ages of 32 and 70 are currently being enrolled at the Kaiser Permanente study site in Oakland, Calif. Stanford University Medical Center will begin screening people for the trial in mid-October. The study will observe participants' reactions to the vaccine and gauge its effectiveness at different dilutions.
Kaiser Permanente has research centers in California, Oregon, Hawaii, Georgia, Colorado, Maryland and Ohio. Kaiser Permanente is a leading integrated healthcare organization. Founded in 1945, it is a non-profit, group-practice prepayment program with headquarters in Oakland, Calif. Kaiser Permanente serves the healthcare needs of 8.4 million members in nine states and the District of Columbia. Nationwide, Kaiser Permanente includes approximately 90,000 technical, administrative and clerical employees and about 11,000 physicians representing all specialties.