Ebola's 'patient zero': A boy playing around a tree

Researchers believe they have found "patient zero" for the 2014 Ebola outbreak in West Africa that left thousands dead and created widespread concern about infection throughout the world.

The source was a 2-year-old boy in Meliandou, Guinea, who apparently played around a tree that was home to a colony of bats, the research team said in a paper published in the EMBO Molecular Medicine journal. The boy contracted the disease and died in December 2013. His family was infected and the disease subsequently spread through his village and on to Liberia, Sierra Leone, Nigeria, Mali and Senegal.

"Our findings support the idea that bats were the source of the current [Ebola] epidemic in West Africa and enlarge the list of plausible reservoirs to include insectivorous bats," the researchers wrote.

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Cases of Ebola are still being reported in Africa. In addition people infected with the disease in Africa also traveled and were treated in the United States, Spain and most recently, Britain. The outbreak has caused a flurry of international activity on infectious disease containment and spurred efforts among governments and corporations to find a possible cure.

Bats are known carriers of the disease. The researchers said they couldn't know for certain whether or not the bats in the tree were conclusively to blame, since the tree caught fire in March, killing the bat colony. Nevertheless, they think the scenario is the answer.

"It [the tree] was near a path where the women would go for washing," said one of the researchers, Fabian Leendertz, a veterinarian at the Robert Koch Institute in Germany, in an interview with Livescience.com. "They would always walk down there with the kids, and the kids would play in this nice tree."

The World Health Organization believes more than 20,000 people have been infected with Ebola, with close to 8,000 deaths. Understanding how the disease originates and spreads is considered vital to containing the current and future epidemics. The first infected human, commonly referred to as "patient zero" by researchers, is a key part of that process.