On Dec. 26, 2013, a 2-year-old boy in the remote Guinean village of Meliandou fell ill with a mysterious illness characterized by fever, black stools, and vomiting.

He died 2 days later. Retrospective case-finding by WHO would later identify that child as West Africa’s first case of Ebola virus disease. The circumstances surrounding his illness were ominous.

The area is notorious for outbreaks of cholera and many other infectious diseases. Though cases of malaria have dropped in recent years, that disease remains the country’s most persistent and prevalent killer.