The current Ebola outbreak may have its ultimate origins in a tree full of bats. These flying mammals may have spread the disease to children as they played outside.

Robert Koch-Institute researchers in Berlin studied insectivorous free-tailed bats, and believe these animals may be the ultimate reservoirs of the virus. They were also able to determine through their study that larger animals were unlikely to be responsible for spawning the disease.

"We monitored the large mammal populations close to the index village Meliandou in south-eastern Guinea and found no evidence for a concurrent outbreak," Fabian Leendertz of the Robert Koch Institute, said.

The Zaire Ebolavirus is one variety of the microorganism which is responsible for causing the illness. The viruses can spread to human directly through contact with the flying mammals, and large animals can also serve as an intermediary. People in the region frequently hunt and eat the creatures, leading researchers to believe the direct route is likely responsible for the current outbreak.

Ebola was first recognized in 1976, when 318 people in Zaire contracted the disease. Of these patients, 280 perished - a fatality rate of 88 percent. Since that time, regular outbreaks of the disease have been seen, although some of the events are minor in scope, such as 2004, when just 18 people were reported to be infected with the illness.

No cases of Ebola were reported by the CDC for more than a decade after 1979. However, between 1989 and 1992, the virus was introduced to Texas and Virginia by monkeys imported from the Philippines. The current outbreak of the disease is, far and away, the most severe ever seen. Nearly 20,000 people have been sickened, and more than 7,700 have died so far from effects of the virus.

It is possible the first person infected with the virus that sparked this year's outbreak of Ebola was a two-year-old boy named Emile Ouamouno. Researchers believe the toddler came into contact with bats as he played inside a hollow tree identified in the study. Villagers reported children often used to play on the tree, exposing themselves to contact with the bats that made their homes there.

The village of Meliandou is a small enclave of just 31 homes, set deep inside the Guinean forest region. This location is surrounded by oil palms, grown for the production of palm oil, as well as tall reeds. Researchers believe these conditions may have attracted vast numbers of the bats.

Young Ouamouno passed away from the disease which has killed so many people on the African continent. While the transfer of the virus is believed to have occured between the boy and the bats, the researchers consider the boy the origin of the outbreak.

Examination of the possible origin of the current strain of Ebola was published in the journal EMBO Molecular Medicine.