The disease Jill Seaman battled is not new. In the 19th century, kala-azar ravaged much of eastern India, where it earned its name--Hindi for "black sickness." In 1900 a British physician, Dr. William Boog Leishman, developed a stain to detect the parasite with a microscope, and Dr. Charles Donovan demonstrated that specimens could be extracted from the spleen. In their honor, the deadly parasite is called Leishmania donovani. Variants of kala-azar are found in southern Europe and South America. A complex treatment involving daily injections of a potentially toxic, antimony-based compound (as in the drug Pentostam) has been available for a half-century.

Although the epidemic in Sudan involved a known disease, it was complicated by the fact that for a long time no one knew the outbreak was occurring. The western Upper Nile is one of the world's most remote areas. It has almost no roads, and the Nuer ethnic group that populates it is extremely isolated. To make matters worse, the Islamic fundamentalist-influenced government in Khartoum was engaged in a civil war with the people of the south, where Christianity and traditional African religions prevail. Displacement caused by the war and famines had further weakened the population, and the government showed no interest in stopping a disease that might prove more effective than armed troops in quelling rebellious groups.

About the time the epidemic was beginning to spread, Khartoum banned relief flights into the south, and most international organizations, including the U.N., stayed out. Medecins Sans Frontieres refused to go along. In the summer of 1988, with a team already in Khartoum, MSF clandestinely sent a second one into the south. The team soon began to hear reports of a strange new "killing disease," which its doctors in Khartoum believed to be kala-azar.

By then Seaman was attending classes at the London School of Hygiene and Tropical Medicine. Four years earlier, she had taken a break from her job in Alaska to work with Ethiopian refugees at a camp in Sudan but came to realize that she needed more training in tropical medicine. When MSF was scouting at the school for a doctor to take on kala-azar in Sudan, she signed up immediately.

Before MSF hired her, there had been a debate within the organization about whether a kala-azar epidemic of such massive size could be handled with no hospitals in the area. "We were going to be dealing with thousands of patients at a time, and we didn't know if it would be possible to do this out in the open and under a tree," says Johan Hesselink, who headed MSF-Holland's southern Sudan operations during that period.

When she finally reached Sudan, even Seaman was not sure what she had signed on for. "My legs swelled up to twice their size with mosquito bites," she says, "and I was ready to cut my one-year contract short by 11 months." But she was clearly captivated by the place and stunned by the enormity of the human catastrophe around the town of Duar, the center of the epidemic. "If you witness a tragedy like that, how can you not be moved?" she explains. "Where else in the world could 50% of a population die without anyone knowing?"