The number of confirmed Ebola cases in Democratic Republic of Congo has risen above 10 000, government data showed on Tuesday, a milestone that coincides with growing fears the epidemic could spread to more African countries.

The latest situation report from Congo's public health institute put the number of cases at 10 060, with those killed by the virus reaching 4 887.

The outbreak, caused by the rare Bundibugyo species of Ebola, was announced in mid-May and has since become the largest and deadliest in Congo, surpassing a 2018-2020 epidemic.

It is now the second-largest and second-deadliest on record behind only the 2014-2016 West African Ebola outbreak, which infected over 28 600 people and killed more than 11 000, mainly in Guinea, Liberia and Sierra Leone.

Earlier this month, Kenya reported its first case and went on to announce nine cases in total, after a man who had travelled from Congo via Uganda died in Nairobi.

Last week, Nigeria became the fourth African country to report an Ebola case.

Health officials have been seeking to work out how and where ​the patient — the wife of a Swiss diplomat, who had not travelled to Congo — ⁠contracted the disease. The Swiss government said she was believed to have contracted it in Uganda.

The woman and her husband were flown to hospitals in Switzerland on Monday.

Uganda reported 20 cases in May and June, mostly imported from Congo, but the World Health Organization declared the country Ebola-free in August.

Ugandan officials say the country does not have any Ebola cases.

Uganda's health minister said on Sunday that Ugandan citizens returning to the country with a history of travel to ​Congo would be quarantined for 21 days.