Three new Ebola cases have been confirmed in the Democratic Republic of Congo's sprawling northwest taking the number of suspected infections to 43, the health minister said in a statement seen Saturday.
Alarm bells sounded on Thursday after the outbreak, previously reported in a remote rural area of the country, notched up its first confirmed case in Mbandaka, a city of 1.2 million.
"Three new cases were reported (in Mbandaka) and tested positive for the Ebola virus," Health Minister Oly Ilungao said in the statement.
"In total, 43 cases of haemorrhagic fever have been flagged in the region of which 17 are confirmed, 21 are probable and five are suspected cases," he said.
In Geneva, the UN's World Health Organization (WHO) put the death toll at 25 but said 45 cases have been recorded, 14 of which have been confirmed by lab tests.
The WHO on Friday said the latest Ebola outbreak did not warrant being labelled an emergency of "international concern", adding that Kinshasa's response along with its own had been "rapid and comprehensive."
The government announced the outbreak of the deadly virus in northwestern Equateur province on May 8.
In the WHO's parlance, "a public health emergency of international concern" is an "extraordinary event" in which a disease may spread across borders and requires a vigorous international response.
Ebola is both lethal and highly contagious, which makes it difficult to contain -- especially in urban environments where people are mobile and come into more contact with others.
It is notorious for its high fatality rate and extreme symptoms, which can include internal and external bleeding.
The current outbreak -- the ninth to hit the DRC since Ebola was identified in 1976 -- involves the same strain of the virus that struck three West African countries in 2013-15 and sparked an international panic. It went on to kill more than 11,300 people in the deadliest ever Ebola epidemic.