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By Peter Gorner
Tribune science reporter
Published December 20, 2002

Widespread vaccinations for smallpox are dangerous and probably unnecessary, but a majority of Americans say they would get inoculated against a disease they seem to know little about, according to studies released Thursday.

The New England Journal of Medicine will publish the findings in its Jan. 30 issue but posted them early on its Web site "to help to inform the current national debate about smallpox vaccination."

The studies highlight the need for public education, experts said, and seem likely to add to the growing debate over the threat posed by a horrible but presumably extinct disease.

A survey of 1,006 Americans by the Harvard School of Public Health found a majority of Americans think the disease still breaks out naturally.

The last case of smallpox was 25 years ago. However, three in 10 Americans believe there have been smallpox cases in the U.S. during the past five years and 63 percent think there were cases somewhere in the world in that period.

No treatment

Although there is no known effective treatment for smallpox, 78 percent of Americans believe the disease is treatable. Between 50 and 60 percent said they would choose to be vaccinated against smallpox.

Given months of news reports and widespread speculation about a potential release of smallpox by bioterrorists, the misperceptions are "staggering," said Robert J. Blendon of the Harvard School of Public Health, who directed the study.

President Bush stressed Friday that there is no imminent threat of an outbreak. And he emphasized that there is enough vaccine for every American, although the Harvard study showed that only 16 percent think this is true.

Government policy

The government's policy of targeting doctors and nurses for vaccination is supported by the detailed analysis in the journal, sponsored by the RAND Center for Domestic and International Health Security.

The RAND study was well done, according to Dr. James J. James, a public health veteran who recently was hired by the American Medical Association to direct its new Center for Disaster Preparedness and Emergency Response.

"If anything, the study tends to validate the current vaccination policy for smallpox," James said. "However, the problem with the study--and with so many things we're hearing about smallpox--is that it's all based on assuming a certain probability.

"In reality, we're not going to actually know if we adopted the right policy until after the fact."

If 60 percent of the country were immunized, there would be about 500 deaths due to complications, a price too steep if there is little chance of a terrorist attack with the smallpox virus, the RAND researchers said.

If nearly all of the 10 million health-care workers in the U.S. were vaccinated against smallpox, about 25 people would die, the RAND study found.

But that risk would be justified, the researchers said, because health-care workers are particularly vulnerable during smallpox outbreaks.

Those workers, who compose about 3 percent of the population, could account for more than half of all smallpox cases under some scenarios.

"It's very beneficial to vaccinate health-care workers, especially those who are likely to be involved in the care of the first patient," said Dr. Gordon Trenholme, director of the vaccination effort at Rush-Presbyterian-St. Luke's Medical Center.

Mass vaccinations not answer

Another expert who approved of the RAND study was Dr. Stanley O. Foster, of Emory University, who worked for the CDC for 30 years and helped wage the war against smallpox with field assignments in Nigeria, Bangladesh and Somalia.

He doubts that mass vaccinations before an epidemic would limit the disease. To Foster, the risks from smallpox vaccination are greater than the risk of smallpox.

"In my own experience, even 80 percent coverage of the population will not prevent the transmission of smallpox," he said.

"In 1969 in Bangladesh, we had 80 percent of the population vaccinated and 7,000 cases of smallpox. In 1972 in Bangladesh, we had 80 percent coverage and 70,000 cases."

It also is dangerous to assume that bioterrorism-induced smallpox would act like natural smallpox, Foster cautioned.

"But I've learned that finding cases, vaccinating and isolating them, then tracking down and vaccinating all the people they've been in contact with--those are the best ways to stop the spread of smallpox."

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