A global network of researchers has found a new virus—related to the virus that causes rabies—that may be responsible for three cases of acute hemorrhagic fever in the Democratic Republic of the Congo (DRC) during 2009, according to a study in PLOS Pathogens released last week (September 27).
In the summer of 2009, two patients—teenagers from the Mangala village in the southwest corner of DRC—exhibited unexplained symptoms of hemorrhagic fever, including vomiting blood, fever, and bleeding from mucus membranes, and died after 3 days. When a third patient fell ill—the nurse who cared for them—medical experts transferred him to the regional hospital where he recovered, and sent his blood samples to a series of research labs for analysis.
Though researchers weren’t able to isolate the novel rhabdovirus—dubbed for the province where Mangala is located—they were able to sequence nearly 100 percent of its genome using a technique called deep sequencing. The method allowed researchers to amplify 140 million fragments of viral DNA sequences from the blood and assemble the genome by identifying related fragments.
“It looks fairly solid,” Thomas Ksiazek, an epidemiologist and virologist specializing in hemorrhagic disease at the University of Texas, who was not involved with the study, told ScienceNOW. “Clearly, they have identified a virus in one of the three patients they describe. But trying to make more out of this is speculative,” until the virus can be isolated and directly linked to the disease.
The authors also emphasize the importance of finding the virus itself. “Since we weren't able to get an isolate, that limits what we can know about how it kills people and the effect it has on the immune system,” virologist Joseph Fair, who works at Metabiota, the San Francisco-based company that sequenced the virus, told ScienceNOW. “Along with our Congolese colleagues, our next step will be to mount an expedition to find this virus.”