Dec. 29, 2015 -- The United Nations' World Health Organization on Tuesday declared the West African nation of Guinea to be free of Ebola.
Guinea was home to the first known case of Ebola, occurring in a small boy named Emile Ouamouno in December 2013. The boy died of the disease, CNN reported.
The outbreak -- which eventually infected more than 28,000 people and killed more than 11,200, making it the worst Ebola outbreak ever -- was centered in Guinea and two other West African nations -- Liberia and Sierra Leone.
WHO earlier declared Liberia and Sierra Leone free of Ebola. The agency has made the declaration for Guinea because 42 days have passed since the last Guinean Ebola patient tested negative for the virus for the second time, CNN said. Guinea now goes into a 90-day period of heightened surveillance to make sure that any new cases are spotted quickly, WHO said.
"The coming months will be absolutely critical," Dr. Bruce Aylward, the head of Ebola response for the WHO, told CNN.