The new case is the wife of a miner who died of the virus earlier this week and who only sought treatment more than a week after starting to show symptoms, authorities said.
An outbreak on Ebola has killed more than 1,800 people in other parts of Democratic Republic of Congo since it was declared one year ago, making it the second-worst on record. Two people have died in Uganda, which also borders Congo, but no registered cases have occurred in Rwanda. On Thursday, Rwanda briefly shut its border crossings with Congo around the city, after the new cases emerged.