The House yesterday rejected a Republican plan meant to encourage medical workers and emergency responders to get immunized against smallpox, after Democrats said the package wasn't generous enough.

Supporters said the incentives are vital if the nation is to prepare for a possible terrorist attack involving smallpox. Only about 25,000 health care workers have volunteered to be vaccinated, far short of the 500,000 target President Bush had hoped to reach by March 1.

Under the bill, any health care workers or "first responders" who died or were permanently disabled due to a smallpox vaccination would be eligible for the same federal benefits -- up to $262,000 -- that the families of police officers and firefighters receive. In cases of less devastating injuries from vaccinations, the government would provide 66 percent of the victim's annual salary (or 75 percent if there were dependents), up to $50,000 a year -- but no more than $262,000 in all.

GOP leaders brought the legislation to the floor under the "suspension calendar," which requires a two-thirds vote for passage and is usually reserved for noncontroversial bills. The measure, however, did not win even a simple majority, failing on a 184 to 206 vote.

House leaders said they remain determined to pass the measure, perhaps by attaching it to a popular bill. "We need to get this done in the relatively near future," said Majority Whip Roy Blunt (R-Mo.).

In yesterday's debate, Energy and Commerce Committee Chairman W.J. "Billy" Tauzin (R-La.) told colleagues, "This is an emergency. This [bill] will ensure we will have the people ready to vaccinate all of America if, God forbid, we suffer a smallpox attack."

But several Democrats, who had negotiated unsuccessfully with key Republicans to change the bill, said that without greater financial assurances, nurses, firefighters and police officers would not take the risk of being vaccinated.

Federal health officials have grown worried about a surprising number of cardiac-related problems in recently immunized people. One serviceman was hospitalized over the weekend with severe inflammation in and around the heart, said Col. John Grabenstein, who has overseen vaccination of 350,000 Defense Department employees. The military is investigating 14 such cases, known as myocarditis or pericarditis, he said.

In the civilian program, the Centers for Disease Control and Prevention in Atlanta is studying at least seven coronary complications, including two fatal heart attacks. Yesterday, the CDC announced it would adopt stricter screening guidelines recommended by its vaccine advisory committee. The agency now recommends that anyone with known heart disease, such as angina, or risk factors for heart disease such as high cholesterol, smoking and hypertension, not be inoculated.

In Congress, Rep. Lois Capps (D-Calif.), who was a nurse before coming to the House, told reporters, "Our first responders must know that in the event of an adverse or even fatal reaction, their needs and the needs of their families will be taken care of." The GOP bill, she said, "makes our first responders beg for help. It nickels and dimes the very people who will care for us in an emergency."

House Democrats said that in the event of a death or a serious disability linked to smallpox vaccination, the victim's family should receive $75,000 a year in benefits, with no cumulative limit. Their plan would require Congress to appropriate money for the compensation fund, whereas the GOP plan would leave the matter to the appropriations committee.

Tauzin grew visibly exasperated during the debate, suggesting Democrats were being reckless by refusing to make additional concessions. "I thought every night when I was negotiating this bill, 'What if tomorrow we have an attack?' " he said. "If nothing passes, it's only because somebody on the other side thinks it's never enough."

Staff writer Ceci Connolly in Atlanta contributed to this report.