Forty-four confirmed and probable cases have been recorded since the disease broke out in the province of North Kivu on August 1, the health ministry said.
Two suspected cases in Goma, a city of about a million people, “turned out to be negative” on Thursday after lab tests, it said.
The outbreak is the country’s 10th since 1976, when the disease was first identified in the DRC near the Ebola River, a tributary of the Congo.
The latest outbreak is centered in North Kivu’s Beni region, which shares borders with Uganda and Rwanda.
The area is plagued by violence — a problem that the World Health Organization (WHO) has said will hamper the emergency response. Targeted vaccination, aiming primarily at front-line health workers, began on Wednesday.
Ebola causes serious illness including vomiting, diarrhoea and in some cases internal and external bleeding. It is often fatal if untreated.
In the worst Ebola epidemic, the disease struck the West African states of Guinea, Liberia and Sierra Leone in 2013-15, killing more than 11,300 people.
The outbreak in North Kivu was declared a week after WHO and the Kinshasa government hailed the end of a flareup in northwestern Equateur province which killed 33 people.
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