The transmission of the Ebola virus has been stopped in West Africa, the World Health Organization declared Thursday in Geneva.
WHO experts warned, however, that there was still a risk that the haemorrhagic fever could flare up again, as the virus can persist for up to 12 months in the semen of male survivors.
The WHO announcement came 42 days after the last case was confirmed in Liberia, the final of three West African countries with active transmission of the virus.
Sierra Leone was declared free of Ebola transmission on November 7 and Guinea on December 29.
More than 11,300 people have died since the outbreak in December 2013 in West Africa, while 28,500 have been infected.
"Detecting and breaking every chain of transmission has been a monumental achievement," WHO Director General Margaret Chan said.