A group of articles in an influential medical journal has raised questions about the government's new smallpox vaccination policy, saying that inoculating the public is too risky and that a terrorist-induced outbreak of the disease might not cause widespread infection.

Researchers support vaccinating health-care workers before a possible attack, a cornerstone of the Bush administration's plan, but disagree over how many should receive the vaccine, which can lead to fatal complications for one or two of every million people inoculated.

Dr. Thomas Mack, a professor of preventive medicine at the University of Southern California's Keck School of Medicine, said that the disease is "not as infectious as its reputation would suggest" and that transmission would be expected only over short distances.

"Our greatest concern should be about transmission within hospitals," he said in the New England Journal of Medicine, which is publishing an issue devoted mostly to smallpox next month. The journal released the articles yesterday to the media.

Mack questioned the effectiveness of vaccinating hundreds of thousands of health care workers across the country, as the White House has planned. He recommended instead inoculating 15,000 health professionals.

"A terrorist introduction of smallpox could produce a short outbreak of cases and deaths, but the current vaccination policy will provide little protection, and the cost in deaths from vaccine complications will outweigh any benefit," he said. "Only if evidence suggests that a massive attack or sustained biological warfare is probable can such a vaccination policy be justified."

Last week, President Bush ordered military personnel in high-risk areas to get vaccinated promptly and said the vaccine would be offered soon to about 450,000 civilian health-care workers - including about 6,000 in Maryland. The public will be offered the vaccine on a voluntary basis, but likely not until 2004, when a new vaccine is ready.

But researchers from the Rand Center for Domestic and International Health Security said in a separate article in the Journal that they do not endorse a public vaccination campaign "because the certainty of harm outweighs the small chance of a net benefit."

They do, however, support the vaccination of health-care workers - a step they said should sharply reduce the "disproportionate burden" of disease among that population if an outbreak occurs. Vaccinating hospital workers in advance will also provide protection to their families, Rand researchers said.

Smallpox, which was declared eradicated more than two decades ago, is fatal in about a third of its victims. But the vaccine protecting against it poses substantial risks, too, particularly for those with compromised immune systems or skin conditions such as eczema.

Experts estimate that the vaccine, which is made from a live virus, will produce life-threatening complications in about 15 out of every 1 million people who receive it.

In a demonstration of his faith in the vaccine, Bush has said he will receive it. But a growing number of hospitals are either opting out of the federal plan to vaccinate health care workers or are raising serious doubts about it.

In Illinois, two hospitals have notified the state health department that they would not vaccinate employees because of the risks. In Atlanta, Emory Medical Center, which is affiliated with the U.S. Centers for Disease Control and Prevention, said it had not decided.

In Baltimore, Johns Hopkins Hospital is working to meet a request by the Maryland Department of Health and Mental Hygiene to provide 250 workers for vaccination, said a spokeswoman, adding that Johns Hopkins Bayview will try to provide 175 employees. Howard County General Hospital will try to get 100 workers inoculated. The University of Maryland Medical Center has been asked to inoculate 250 but is unsure how many will be vaccinated.

Tara O'Toole, director of the Johns Hopkins Center for Civilian Biodefense Strategies, said she agrees with the journal authors that the public should not be vaccinated before an attack or the imminent threat of one.

"The adverse reactions from the vaccine are real, and the threat as yet is indeterminate," O'Toole said. But she said the nation is sadly unprepared to respond to the large numbers of people who would demand vaccines should the threat change.

O'Toole said she agrees with the Bush administration's plans to vaccinate half a million health-care workers as a precaution. Protecting 15,000, as USC's Mack suggested, would leave each of the nation's 5,000 hospitals with an average of three people to greet patients at the door, she said, and would leave hospitals vulnerable to epidemics within their walls. "I would argue, if anything, that 500,000 is not enough," she said.

Dr. Georges Benjamin, president of the American Public Health Association and Maryland's former health secretary, said any vaccination campaign needs to be carried out in a "measured manner."

"We're not sure yet that the public has been educated enough ... to make a fully informed decision," he said.

Benjamin added that many practical issues still need to be worked out regarding health-care workers. Many of those vaccinated will get sick - normal reactions include a low fever and swollen glands in the armpits - prompting questions about how hospitals will handle staff absenteeism, whether workers will be paid for those days off and what to do about those without health insurance.

Researchers at the Harvard School of Public Health reported in another Journal article that the public has many misconceptions about smallpox. Most of the more than 1,000 adults surveyed at random falsely believe, for instance, that there is an effective treatment for the disease; a substantial portion thought there have been cases in the past five years.

The last case of smallpox in the United States was in 1949; the last in the world occurred in 1977.

Sun staff writer Diana K. Sugg contributed to this article.