"A total of 12 people from various centres on the outskirts [of Goma] are undergoing testing after the response team triggered the alert protocol", the Congolese government said in a statement.
PCR testing for Ebola by the National Institute of Infectious Diseases was negative, as was testing for malaria.
The disease has killed more than 1,800 people in the Democratic Republic of Congo since the latest outbreak was announced in August 2018.
"The gold miner. will have contaminated several people, but for the moment it is only his wife and one of his ten children who are sick", Muyembe said. His wife, also infected, and the young girl were in stable condition on Saturday, the presidency said.
Earlier last week, Rwanda Health officials confirmed the detection of a second Ebola case in Goma, a city near Gisenyi on the Rwandan side, involving a 46-year-old man who had travelled from a community near Bunia in Ituri province.
"The individual concerned spent time with his family being very symptomatic within the community".
But he warned that about half of the cases in this outbreak are going undetected and at that rate "this epidemic could last two or three years".
The Ebola virus can spread quickly and be fatal in up to 90% of cases.
The Ebola outbreak in the DRC was declared a Public Health Emergency of International Concern, having spread into the eastern capital Goma which is hard by the frontier with both Uganda and Rwanda.
Travellers coming from Malawi will be monitored for the disease using a scanner, Hidayate Kassim, the provincial health director of the Zambezia region in Mozambique, told reporters, citing reports of "suspected" cases of Ebola in Malawi that have not been confirmed. It is not good that Ebola has resulted in the death of two people in the city which shares a land border with Rwanda.
Ebola virus causes haemorrhagic fever, vomiting and severe diarrhoea, often followed by kidney and liver failure and internal and external bleeding.
People can be infected with Ebola either through contact with infected animals or through contact with bodily fluids from infected humans.
While there is no medical cure for Ebola, new tools including a trial vaccine, experimental treatments and futuristic cube-shaped treatment units have helped limit its spread.
The Security Council called for an immediate end to hostilities among armed groups whose activities compromise the Ebola response, and for an end to attacks on health and humanitarian workers.