People began dying of the suspected fever two weeks ago in the Mweka area of the province of Kasai Occidental, said Jean-Constatin Kanow, the chief medical inspector for the province.
Congo has in the past seen large outbreaks of Marburg and Ebola, both hemorrhagic fevers caused by viruses that in severe cases attack the central nervous system and cause bleeding from the eyes, ears and other parts of the body.
"We began by suspecting typhoid fever, but now we believe its hemorrhagic fever," said Kanow.
The deaths began following the funeral of two village chiefs. "Everyone that attended those funerals is now dead," said the medical inspector.
In all, four villages are affected and 217 people have come down with the illness, including 103 who died. Of the dead, 100 were adults and three were children, said Kanow.
Two medical teams from the province's administrative seat have been sent to Mweka, an area that has a population of 140,000. A third team from the National Institute of Biomedical Research was expected to arrive Wednesday from Kinshasa, the capital, 430 miles northwest of Mweka.
The researchers were planning to take blood samples to be analyzed at laboratories specializing in hemorrhagic fever.
Congo's last major Ebola outbreak struck in Kikwit in 1995, killing 245 people. Kikwit is about 200 miles from the site of the current purported outbreak.