Ebola virus hotspots are more widespread across Africa and are carried by a greater number of animal species than previously suspected, according to a recent study published in the science journal Mammal Review.
The study was led by scientists from the Center for International Forestry Research, also known as CIFOR, and other international universities.
The report challenges the notion that the Ebola virus is mainly carried by three species of fruit bats. It found numerous potential animal carriers including rodents, primates, hoofed mammals, civets and shrews.
“The most important aim of what we were doing was to see if we could understand better the factors that may be linked to the presence of the Ebola virus,” said Professor John Fa, one of the lead authors of the study and
researcher for CIFOR and faculty member at Manchester Metropolitan University in the United Kingdom.
The research was performed by scientists who looked at climates, types of forests, and animals that would likely be the hosts of the virus.
“By doing the work that we have done, we were able to better map the areas which are favorable for the Ebola virus," he said. "And in so doing we can then start looking at these particular areas and hopefully come up with an early warning system that will say, 'Well, these areas are more likely to be the places where the disease might happen.'"
Central and West Africa
The study found that areas within Central Africa, such as the western part of the Congo basin, and West Africa are very favorable areas for the Ebola virus.
“Tropical forest areas are the ones where the Ebola virus seems to like," Fa said. "That doesn’t mean that it can’t occur somewhere else at some particular point in time. What we’re saying is that given the information that we have, there is a very strong association between tropical rain forests and the Ebola virus."
Science has proved the Ebola virus does require the body of an animal to survive. Without the animal host, the virus cannot reproduce and infect other animals.
Many potential hosts
Fa said the study found a wide variety of animals can be potential hosts.
“The story that has been up to now is that there are only three possible species of mammals that may be the transmitters of the disease, and these are three fruit bats," he said. "We show in our study that we’ve got to be cautious about that because currently there isn’t sufficient evidence to clearly state that these three bats are the only ones responsible for the transmission of the virus."
The wider range of animals flagged as potential carriers of the disease include more than 60 species of animals.
Because of this, Fa said they have to look at the Ebola picture in a different way.
“It doesn’t mean we have to go out and start killing everything that is in the list of animals that we have in our paper," he said. "It means that we have to understand the processes."
The researcher, who is also an expert on bush meat, said a lot of work needs to be done within local communities, especially with hunters, to find out the best way to eliminate the risk of transmission of Ebola from animals hunted for food.
Fa said the study was the first step in analyzing how the Ebola virus is transmitted from animals to humans.
“Now the next step has to be to look at the transmission dynamics of humans to humans,” he said.