Mali's health minister says the country is now free of the Ebola virus, after 42 days without a new case of the disease.

"I declare this day... the end of the epidemic of the Ebola virus in Mali," said Ousmane Kone.

The last Ebola-infected patient in Mali recovered and left hospital in early December.

Latest figures show the three West African countries worst affected have all seen a decline in new Ebola cases.

Sierra Leone and Guinea both recorded the lowest weekly total of confirmed Ebola cases since August, according to UN figures on Thursday.

Liberia, which reported no new cases on two days last week, had its lowest weekly total since June.

The overall death toll has reached 8,429 with 21,296 cases so far.

Mali recorded its first case of Ebola in October, when a two-year-old from Guinea fell ill and died.

At its worst, there were 300 contact cases under investigation in the country.

But the country has now "come out" of the epidemic, said Ibrahima Soce Fall, the head of the Malian office of the United Nations Mission for Ebola Emergency Response (UMEER).

The incubation period for Ebola is 21 days, and countries must be free of new cases for two consecutive incubation periods, 42 days, to be declared free of the virus.

Ebola virus disease (EVD) 1. Symptoms include high fever, bleeding and central nervous system damage 2. Spread by body fluids, such as blood and saliva 3. Fatality rate can reach 90% - but current outbreak has mortality rate of about 70% 4. Incubation period is two to 21 days 5. There is no proven vaccine or cure 6. Supportive care such as rehydrating patients who have diarrhoea and vomiting can help recovery 7. Fruit bats, a delicacy for some West Africans, are considered to be virus's natural host