FARMINGTON, Connecticut (CNN) -- Four doctors and other health care workers rolled up their sleeves Friday and received inoculations against smallpox, a disease that was declared eradicated more than two decades ago but has re-emerged as a potential terrorist threat.
The health care workers in Connecticut were offered the inoculations as the second phase began of President Bush's plan to counter any possible smallpox bioterror attack.
By April 1, people who received inoculations will administer the same vaccine to about 4,000 other Connecticut residents deemed "first responders" -- public health and hospital workers who would provide mass inoculations to the public should an outbreak be reported, said Ken Roberts, a spokesman for the Connecticut Hospital Association.
Friday's inoculations were carried out using the first shipment of vaccine to state and local governments under Bush's plan to protect Americans from an intentional release of the virus. So far, 20 states have requested nearly 100,000 doses of the vaccine, the Centers for Disease Control and Prevention said.
The CDC has begun distributing vaccine and needles for 21,600 public health and health care workers in Connecticut, Nebraska, Vermont and Los Angeles County.
Those people who get the vaccine will be checked at seven days and three weeks after their upper arms are jabbed 15 times by a double-pronged needle dipped in vaccine.
In addition, health care workers who have close contact with patients will have their injection sites monitored daily to ensure the lesions are covered so that the cowpox used in the vaccine is not spread through casual contact.
Dr. Michael Grey, who leads a team of "first responders," was one of those who volunteered.
"I think the risk of not doing anything ... is too great, even though the risk of a smallpox attack is small," he said.
Vaccine carries risk
The vaccine, which has not been routinely given in the United States since 1972, does have risks. Health officials estimate one or two people out of every million who get the vaccine will die from it.
Most people experience mild reactions to the vaccine, according to health officials. In recent tests, one in three people felt bad enough to miss work or school or had trouble sleeping. But about 1,000 out of every 1 million people vaccinated are expected to need medical attention.
In all cases, smallpox vaccination is voluntary, officials said. "If you're going to allow people, even voluntarily, to get vaccinated, it's important that they truly understand, as best as you possibly can communicate to them, that there are risks associated with the vaccine," said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
The health commissioner for Connecticut, Dr. Joxel Garcia, said he might be vaccinated "in the next few weeks."
People most at risk are those whose immune systems are impaired. People who have a serious case of the skin condition eczema and people who are being treated for cancer or who have received an organ transplant or are infected with HIV, the virus that causes AIDS, are most vulnerable, said Dr. D.A. Henderson, who led the successful fight to eradicate smallpox in nature. The World Health Organization declared that effort a success in 1979.
Under the Bush plan announced in December, about 500,000 troops deployed in high-risk parts of the world began vaccinations in the first phase of the plan.
The second phase will be to vaccinate about 440,000 public health care workers, emergency room doctors, disease detectives and other hospital officials. It will also be made available to up to 10 million police, firefighters and other first responders on a voluntary basis.
Because about half of U.S. residents have never been vaccinated, and those who were vaccinated are believed to have limited, if any, immunity, the country is an especially vulnerable target.
"We have a substantially nonimmune population, and that's a very risky situation if we face a malicious bioterrorism dissemination of smallpox," said Dr. Bill Bicknell, with the Boston University School of Public Health in Massachusetts.
Not recommended for public
The vaccine is not recommended for the general public, but some say they would feel safer if they received the shots.
Nicole Zimmer said she felt vulnerable because of the threat of terrorism and wanted the vaccine to ease her mind. The only way the general public can get the vaccine is by joining a clinical trial, so she participated in one at St. Louis University.
"I was very fearful that everything that I had heard about it would actually come true," Zimmer said. "And one day I would wake up and hear that there had been bioterrorism and release of smallpox."
In September, the CDC put together guidelines for all 50 states and the District of Columbia with instructions on how to vaccinate entire populations within a week of an outbreak.
And though the shots are voluntary, health groups are divided over the issue. A panel convened by the Institute of Medicine recommended to the White House last week to more explicitly outline the health risks and to wait after the first round of inoculations before offering the vaccine to millions of other workers.
Dr. B.A. Rubin, who designed the bifurcated needle used in the inoculations, said he has urged physicians not to participate in the program.
Despite the fact that recipients must sign a waiver before receiving the vaccine, "no matter what they sign, there are going to be a lot of lawsuits," he predicted.
"If you want to avoid trouble, just don't do it. First of all, I think it's unnecessary, and it's a lot more hazardous than people are led to believe. I myself have had the experience of vaccinating adults who never have been vaccinated [as children]. One hundred percent get reactions, and some are very nasty."
Friday's inoculations are not the first in recent years. The virus has been stored at the CDC in Atlanta, Georgia, and at a research facility outside Moscow. There, researchers are vaccinated before they work with the virus, which is easily spread.