The proposal, which Congress would have to approve, is based on a similar compensation package now available to police officers and firefighters injured on the job.

Under the plan, the government would pay $262,100 for each person who dies or is permanently and totally disabled by the vaccine. Those less severely injured could receive up to $50,000 plus medical expenses.

The vaccine, effective in preventing the transmission of the highly contagious disease, carries rare but serious risks, including death. Smallpox was declared eradicated globally in 1980, but there is fear it could return in an act of bioterrorism.

The plan announced Wednesday by the Health and Human Services Department would compensate people who are being asked to participate in the vaccination program — as many as 10.5 million health care workers and emergency responders. The fund also would cover people injured because they came into contact with a vaccinated worker.

"We are asking these health professionals to perform a vital public duty, so we are proposing to provide them the same sort of benefits that we provide our public safety officers when they are injured on the job," Julie Gerberding, director of the Centers for Disease Control and Prevention, said in a statement.

The government is making the vaccine available to the general public but not recommending it, and these people would not be eligible for compensation from the fund.

An existing federal compensation fund covers those injured by other vaccines, but not smallpox. People injured by the smallpox vaccine are not likely to be fully compensated for lost wages or medical expenses without a separate fund.

That partly explains the tepid early response to the federal vaccination program, according to state and local officials, unions, hospitals and health care workers.

Federal officials initially aimed to vaccinate as many as 450,000 people on special smallpox response teams in about a month. As of Tuesday, about six weeks into the program, 12,404 people had been vaccinated.

Officials are hoping the fund will increase the numbers. "We would expect that this would provide a level of comfort to those who are concerned about the vaccine," said Jerry Hauer, the top bioterrorism official at HHS.

The nation's largest union of health care workers agreed.

"The administration has given the smallpox program a much-needed shot in the arm," said Andy Stern, president of the Service Employees International Union, which represents 750,000 nurses and other health care workers.

But the American Nurses Association worried that the payments are not large enough and many people won't qualify because they are sick for just a few days.

"The compensation doesn't kick in until a person has been out five days," said Carol Cooke, spokeswoman for the nurses' union.

The government said its compensation plan, modeled after the Public Safety Officers Benefit program, would:

• Offer $262,100 for people who die or are permanently and totally disabled because of the vaccine. The money would be paid even if the victim had other death benefits.
• Pay up to $50,000 in lost wages for people temporarily or partially disabled by the vaccine. The government would pay two-thirds of lost wages after the fifth day away from work, with a maximum of $50,000. This would be in addition to any workers' compensation or disability insurance benefits available.
• Pay reasonable out-of-pocket medical expenses, other than minor injuries, for people injured. This would be secondary to any health insurance benefit available.
• Retroactively cover everyone who has been vaccinated since Jan. 24, when the civilian program began.

The smallpox vaccine is made with a live virus called vaccinia, which is related to smallpox and can infect the body. Experts estimate that as many as 50 people out of every 1 million vaccinated for the first time will face life-threatening complications, and one or two will die. Reactions are less common in people being revaccinated.

Officials in Florida, Minnesota and Virginia have said they are investigating a handful of cases of people sickened after getting the vaccine, and there have been several reactions among military personnel being vaccinated. None of the reported reactions have been serious.

The most common serious reaction comes when vaccinia escapes from the inoculation site, often because people touch the site and then touch themselves or someone else. The virus transferred to the eye, for instance, can cause blindness.

More deadly is encephalitis, which can cause paralysis or permanent neurological damage. Also fatal though very rare is progressive vaccinia, where the vaccination site does not heal and the virus spreads, eating away at flesh, bone and gut.