Researchers believe that the
index case was a two-year-old boy who lived in the village of
Guéckédou located in the
Nzérékoré Region of
Guinea. Researchers from the
Robert Koch Institute in
Berlin believe the boy contracted the virus while playing near a tree that was a roosting place for
free-tail bats infected with the virus. Dr Fabian Leendertz, an epidemiologist who was part of the investigative team, said Ebola virus is transmitted to humans either through contact with larger wildlife (gorillas, monkeys), or by direct contact with bats. The boy, later identified as Emile Ouamouno, fell ill on 2 December 2013 and died four days later.
 The boy's sister fell ill next, followed by his mother and grandmother.
 It is believed the Ebola virus later spread to the villages of Dandou Pombo and Dawa, both in Guéckédou, by the midwife who attended the boy. From Dawa village the virus spread to Guéckédou Baladou District and Guéckédou Farako District, and on to
Although Ebola represents a major public health issue in
sub-Saharan Africa, no cases had ever been reported in West Africa and the early cases were diagnosed as other diseases more common to the area such as
Lassa fever, another
hemorrhagic fever similar to Ebola. Thus, it was not until March 2014 that the outbreak was recognized as
Ebola. The Ministry of Health of Guinea notified the
World Health Organization (WHO), and on 23 March the WHO announced an outbreak of Ebola virus disease in Guinea with a total of 49 cases as of that date.
 By late May, the outbreak had spread to
Conakry, Guinea's capital, a city of about two million inhabitants.