Federal health officials said Tuesday that they are investigating whether the smallpox vaccine contributed to the heart attack of a Maryland health-care worker who died Sunday.
They also are investigating the case of another vaccine recipient who suffered a heart attack and is on life support, as well as cardiac problems among five other health-care workers who volunteered for the government's smallpox vaccination program.
Medical experts do not believe the vaccinations caused the heart attacks, said Dr. Julie Gerberding, director of the federal Centers for Disease Control and Prevention.
But it is possible that the vaccine, which is made of a live virus related to smallpox, caused some inflammation that in turn worsened preexisting health conditions, she said.
"As a precautionary measure," Gerberding said, Health and Human Services Secretary Tommy G. Thompson decided Tuesday that, for now, individuals with a history of heart disease should not be vaccinated against smallpox.
The new policy and the news of the first death of a vaccine recipient mark the latest setbacks for the 2-month-old program, which has been plagued by low participation.
But officials emphasized that vaccinations of health-care workers and first-responders -- those who would be the first to investigate and treat victims of a potential terrorist attack using the virus -- would continue.
"We are certainly not stopping the program," Gerberding said. "This is still critically important to our preparedness capacity.... The potential for terrorism has probably never been higher."
Immediately after Thompson's decision, CDC officials organized a conference call to tell state public health officials about the new vaccination guidelines. Beginning today, health-care workers volunteering for the vaccine will be asked if they have a history of heart problems or health conditions that contribute to cardiac disease.
If they do, they will be told that they do not qualify for the vaccine.
Individuals vaccinated in the previous two months of the program also will be notified of a possible risk of heart problems.
"We want to err on the side of safety," Gerberding said.
Many state health officials responded in kind.
"Within 15 minutes of getting off the CDC call, we called people in our nine emergency preparedness regions," said Tim Church, spokesman for the Washington State Department of Health.
All three heart-attack victims were women in their 50s with "very clear risk factors" for heart disease, including diabetes, obesity and high blood pressure, Gerberding said. Their heart problems began within five to 17 days of their vaccination, she said.
Karen Black, spokeswoman for the Maryland Department of Health and Mental Hygiene, said the Maryland health-care worker had been vaccinated March 18. She died Sunday while in Virginia, and health officials there will conduct an autopsy.
Federal and state officials are closely following the health reactions of vaccine volunteers.
CDC officials already had reported the cases of five individuals who suffered chest pains or other cardiac symptoms sometime after receiving the smallpox vaccine, noting that previous studies had indicated no connection between the vaccine and heart problems. One of those workers, who was found to have suffered a heart attack, was hospitalized and released.
The government's previous smallpox vaccination program, which ended in 1972, was directed primarily at children, while participants in the current program -- mostly public-health workers and doctors and nurses -- are more likely to be middle-aged.
Gerberding emphasized the preexisting conditions of those who experienced heart problems and said she was "not prepared to discourage [all] older workers from getting vaccinated."
The government's new review of heart problems from the vaccinations, which officially begins today, will include all seven cases of cardiac problems.
When President Bush announced the vaccination program in December, the administration set a goal of vaccinating up to 10 million front-line health-care workers and police, fire and medical emergency personnel within a few months.
But concerns that the vaccine's risks are greater than the threat of attack, as well as the lack of a government plan to compensate volunteers injured by the vaccine, have generated controversy and dampened interest in the program.
Earlier this month, administration officials unveiled a proposed compensation fund, hoping to jump-start the stalled vaccination program.
But a Senate committee failed last week to pass the administration's compensation bill. Some Democratic members said the compensation amounts were too low, and they objected to a provision that would protect manufacturers of childhood vaccines from lawsuits.