Centers for Disease Control and Prevention ( news - web sites) Director Julie Gerberding told the Appropriations Subcommittee on Labor, Health and Human Services ( news - web sites), and Education that at an estimated cost of $13 per dose, states should have enough money from previous federal bioterrorism preparedness funding to vaccinate up to 450,000 health care workers.

Those workers would, in turn, be responsible for a second phase of the effort that could vaccinate as many as 10 million "first responders" to a potential outbreak.

But Patrick Libbey of the National Association of County and City Health Officials, said he "respectfully disagreed" with Gerberding's assessment.

Because administering the smallpox vaccine involves major preparation and follow-up, "smallpox vaccination is costing localities from $142 to $220 per person, according to preliminary estimates from four large urban public health agencies," he said.

Jane Colacecchi of the Iowa Department of Public Health ( news - web sites) said that smallpox efforts are already crowding out efforts to prepare for other forms of bioterrorism.

"Our priority has been changed from building a system of multi-threat bioterrorism preparedness to preparedness for a single biological agent," she testified. And the money being diverted to smallpox vaccine efforts, she added, is negatively impacting other public health priorities, such as childhood immunizations, flu shots and the prevention and treatment of sexually transmitted diseases.

"Some of these programs may have to be delayed or canceled to meet the needs of the smallpox vaccination program," she testified.

Witnesses also complained that the lack of a compensation program for those injured by the vaccine's side effects is slowing the project.

"State and federal workers' compensation programs do not provide an adequate safety net" for those who suffer an adverse reaction, testified James August of the American Federation of State, County and Municipal Employees (AFSCME).

"In a classic Catch-22 situation, one AFSCME local has reported that due to the voluntary nature of the vaccination, medical expenses resulting from a serious injury will not be covered by the workers' compensation program. These same workers have also been informed that their health insurance coverage will not apply because the injury would be considered work-related," August said.

Finally, some health facilities have declined to participate in the program, because, they say, the risks associated with the vaccine appear greater than the possibility someone will use smallpox as a weapon.

"Due to advances in medical treatment, both the risks and the risk pool have increased dramatically over the last 20 years," said Dr. Louis Bell, of the Children's Hospital of Philadelphia. Because so many of the hospital's patients have compromised immune systems, he said, "we are concerned that the introduction of newly vaccinated health care workers could expose our patients and employees to unnecessary risks."