"One of the defining features of this epidemic is the fact that three health professionals have been affected", Health Minister Oly Ilunga said in a statement.
Nigeria was declared free of Ebola October 2014, by the World Heath Organization, after 42 days had passed since tests showed the last infected person no longer had the disease.
The Ebola cases were confirmed after officials in the capital, Kinshasa, were alerted early this month to the deaths of 17 people from a hemorrhagic fever in recent weeks. He said the situation calls for an immediate and energetic response.
Teams from the Ministry of Health, the World Health Organisation and Medicins sans Frontieres have been deployed to the area. In a statement the service's director general, Dr. Anthony Nsiah Asare said alert has been sent to "hospitals and all other relevant agencies and institutions".
The proposed friendly game between Nigeria and Congo DR is under threat following the outbreak of Ebola in the Central African nation.
The incident in the town of Bikoro comes more than a year after an outbreak in the country killed four people.More news: Latest Star Wars film 'Solo' debuts, gets early praise
"Twenty-one cases of fever with haemorrhagic indications and 17 deaths" have been recorded in Equateur province, it said, citing a notification to the ministry as of May 3. The disease was discovered in 1976 and named after the eponymous Ebola River that cuts across the north of the country.
None of the Ebola outbreaks in Congo have connections to the epidemic that began in 2013 and had left more than 28,600 people dead - nearly all of them in Guinea, Liberia and Sierra Leone - before it was declared over in 2016.
While emphasizing that Cholera is preventable, the Ghana Health Service said the disease can be prevented "by improved environmental sanitation, personal hygiene and drinking safe water".
Adewole explained, "Of course, of great concern to the Federal Executive Council is the outbreak of Ebola in DR Congo".
Congo's vast, remote geography also gives it an advantage, as outbreaks are often localised and relatively easy to isolate. This was well contained through the efficient coordination among the government, health department, global partners and the WHO.
Experts fear it could have an "international impact", considering how quickly the virus decimated West Africa between 2014 and 2016.