Bats harbour Ebola virus
2005-12-01 09:33
Paris - Three species of African fruit bat harbour the Ebola virus, enabling the deadly pathogen to spring out from a natural source and infect animal primates and humans, says a study appearing on Thursday in the British weekly journal Nature.
The bats were captured in Gabon and the Republic of Congo following outbreaks of Ebola among humans and great apes between 2001 and 2003.
More than a thousand small invertebrates were caught and examined in the quest to see whether a natural haven existed for the haemorrhagic fever virus.
The three bat species are the hammer-headed fruit bat (Hypsignathus monstrosus), Franquet's epauletted bat (Epomops franqueti) and the flying fox (Myonycteris torquata).
Blood samples showed they had been infected by the virus, but none bore any signs of sickness, the study says.
Previous research has already shown that gorillas and other apes suffer a greater mortality from Ebola during the dry season in the forests of Central Africa.
This, say the scientists, may be because they come into competition with the bats for scarcer fruit, and thus face a heightened risk of getting bitten.
Another potential form of transmission is from killing and eating the bats, which is a custom among local people.
Facts about Ebola
The study is lead-authored by Eric Leroy of France's Institute of Development Research (IRD).
Ebola first came to light in 1976 in Zaire, now the Democratic Republic of Congo (DRC), and is named after the river with which this outbreak is associated.
It and a cousin called the Marburg virus form one of four categories of viruses that cause viral haemorrhagic fever (VHF), a disease whose outbreaks are invariably sourced to wild animals.
The early signs of VHF are usually a high temperature, exhaustion, dizziness, watery diarrhoea and muscle ache. These symptoms are often mistaken for other fevers, such as flu or yellow fever, because VHF is rare.
As the virus spreads, the feverish patient often starts to bleed under the skin and in severe cases, from the mouth, ears and eyes. Blood loss, shock and organ failure lead to coma and delirium and, in many cases, to death.
- AFP