Liberia has been declared Ebola-free by the World Health Organization (WHO), effectively putting an end to the world's worst outbreak of the disease, according to the BBC.

The "end of active transmission" was declared, after 42 days without a new case in Liberia.

It joins Guinea and Sierra Leone, which earned the status last year.

However, the WHO warned that West Africa may see flare-ups of the virus. It has killed more than 11,000 people since December 2013.