They do not run from the world's most-feared diseases -- they run to them.

They searched door-to-door for smallpox in the villages of India in the 1960s to vaccinate the masses. They went to Africa in 1976 to confront a horrific new disease, later named Ebola, which causes blood to seep from every bodily opening, even the pores of the skin.

In America, they discovered that Legionnaires' disease is caused by a bacterium and were first to document in 1981 a mysterious condition that eventually would be called AIDS.

Members of the Epidemic Intelligence Service -- an arm of the Centers for Disease Control and Prevention in Atlanta -- are on the team investigating the anthrax mystery in South Florida that has killed one man and caused 1,000 more to start precautionary antibiotics. Presumably, they also were sent Friday to New York to help with a new anthrax exposure.

Everything about the cases is perplexing. But if they can be solved, many think the EIS will help make it happen.

"The CDC's Epidemic Intelligence Service model has been replicated in Europe and other countries, so it's not as unique as it used to be," said Dr. Art Reingold, a former EIS agent who now leads the epidemiology program in the School of Public Health at the University of California in Berkeley. "But I would say it is unequaled anywhere in the world."

The EIS still is called to help with outbreaks worldwide, but Oct. 4, the destination was Palm Beach County.

Florida's first case

Early that day, a state laboratory in Jacksonville had concluded that the rod-shaped bacteria in a Florida man's lungs were Bacillus anthracis. An anthrax lung infection had not been documented in America since 1976. The case created an instant public-health emergency.

Top officials from the Florida Department of Health flew out of Tallahassee. Within hours, they were joined by 12 people from the CDC, including EIS workers. Two CDC officials also were dispatched to North Carolina, where the man recently visited his daughter.

Family members had taken the 63-year-old Lantana man, Bob Stevens, to a Florida hospital emergency room about 2 a.m. Oct. 2. He was suffering from confusion, high fever and vomiting. He quickly deteriorated. His lungs faltering from the infection, Stevens was put on a respirator to breathe. High-strength penicillin was administered intravenously. He died three days later.

Skin vs. lung infections

By the afternoon of Oct. 4, an investigation was unfolding on two fronts: environment and epidemiology.

Field workers must collect samples from every possible source of contamination in the patient's environment, said Bill Toth, an epidemiologist for the Orange County Department of Health.

Anthrax bacteria is not common in America, but it still lingers in the wild. The bacteria live in the soil and typically infect grazing animals such as cows, sheep and deer. Humans sometimes get infections through the skin by touching a diseased animal, which carries the bacteria on its hide.

These anthrax skin cases are rarely deadly. But the uncommon lung infections usually lead to death. To get infected this way, a person has to breathe in a large number of anthrax spores. If treated before symptoms emerge, the infection can be thwarted.

Investigation branches out

Searching for the bacteria, field workers collected soil and fertilizer from Stevens' garden, then sampled his home and the places he often stopped while riding his bike. They went to his favorite fishing holes and tested the inside of his car.

On the epidemiology end of things, workers began constructing a history of Stevens' movements in the days before he became ill. When Stevens died, investigators were left without their chief witness.