Geneve – Liberia was the last country declared Ebola-free on Thursday.

The World Health Organization (WHO) has declared an end to the two-year Ebola outbreak which has claimed over 11,000 lives across West Africa.

Liberia was the last country in the region to be declared Ebola-free on Thursday.

“The World Health Organization cautions that the three countries [Guinea, Liberia and Sierra Leone] remain at high risk of additional small outbreaks of Ebola, like the most recent one in Liberia,” the WHO said on Thursday.

“We can anticipate future flare-ups of Ebola in the coming year,” UN chief Ban Ki-moon had warned on Wednesday.

“Governments will need resources to help communities prevent infection, detect potential cases and respond rapidly and effectively,” Ban added.

Liberia was first declared free of Ebola transmission in May 2015, but the virus was re-introduced twice since then, with the latest flare-up in November.

It is the first time since the start of the Ebola epidemic about two years ago that all three of the hardest-hit countries – Guinea, Liberia and Sierra Leone – have reported zero cases for at least 42 days.

Sierra Leone was declared free of Ebola transmission on Nov. 7 2015 and Guinea on Dec. 29.

“Detecting and breaking every chain of transmission has been a monumental achievement,” WHO Director-General Dr. Margaret Chan said in a statement.

“We are now at a critical period in the Ebola epidemic as we move from managing cases and patients to managing the residual risk of new infections,” added Dr. Bruce

Aylward, the WHO’s Special Representative for Ebola Response.

The Ebola epidemic claimed the lives of 11,315 people and infected over 28,500.