Ebola may travel on the wing

Researchers combing the forests of Central Africa have found evidence that fruit bats can carry the Ebola virus, a report in the Dec. 1 Nature reveals.

Ebola causes an often deadly hemorrhagic fever in people, but how the virus spreads from place to place and between species has perplexed scientists since human infections were first identified in 1976 in Zaire.

Using nets, the scientists trapped 679 bats and 222 birds, along with 129 rodents and other small ground animals, in an area spanning parts of Gabon and the Republic of Congo. The researchers chose the area because local people there had found gorilla and chimpanzee carcasses infected with Ebola.

Analysis showed that 16 of the bats had antibodies against Ebola virus, and 13 others had Ebola-virus RNA in their livers or spleens, reports virologist Eric M. Leroy of the Centre International de Recherches Médicales de Franceville in Gabon. None of the birds or ground animals was infected, Leroy says.

Curiously, the bats were all healthy. Leroy notes that the natural ranges of the bats found to be infected overlap the sites of past Ebola outbreaks in people. Bats being killed and prepared for food could infect people during handling, Leroy says.

Human contact with infected apes has also been linked to Ebola outbreaks (SN: 2/5/05, p. 84: Available to subscribers at When Ebola Looms: Human outbreaks follow animal infections), and Leroy hypothesizes that fruit bats may spread the virus among gorillas and chimps when the animals compete for food during the dry season.

Education programs warning people against handling or eating meat from both bats and apes might limit Ebola’s spread, the authors note.