"While cases of Ebola Virus Disease have not yet been detected in South Sudan, the risk is high because of movement of people from DR Congo into South Sudan", he said.
The new case of Ebola virus disease has been confirmed in Wangata, one of the three health zones of Mbandaka, a city of almost 1.2 million people in Equateur Province in northwestern Congo, the World Health Organization confirmed Thursday, CNN reported.
Currently, WHO said it considers the public health risk to be high at the national level, moderate at the regional level and low at the worldwide level.
Previous reports of the disease had all been in remote areas where Ebola might spread be more easily contained.
Moreover, WHO has deployed 4,000 experimental Ebola vaccines in DRC and more of the vaccines should reach DRC in the coming days.
The WHO's International Health Regulations emergency committee will determine on Friday if the current outbreak constitutes a public heath event of international concern.
"One new case of Ebola virus disease has been confirmed in Wangata, one of the three health zones of Mbandaka, a city of almost 1.2 million people in Equateur Province in northwestern Democratic Republic of the Congo", the UN's health agency said in a statement.
The city of about one million people is a transport hub on the River Congo, prompting fears that the virus could now spread further, threatening the capital Kinshasa and surrounding countries.
Ebola is an infectious illness that causes internal bleeding and often proves fatal. "We have urban Ebola, which is a very different animal from rural Ebola".
An outbreak in West Africa that began in 2014 left more than 11,000 dead across six countries, and was not declared officially over by World Health Organization until the beginning of 2016.
West Africa experienced the largest recorded outbreak of Ebola over a two-year period beginning in March 2014; a total of 28,616 confirmed, probable and suspected cases were reported in Guinea, Liberia and Sierra Leone, with 11,310 deaths, according to the WHO.
"This is a concerning development, but we now have better tools than ever before to combat Ebola", said Tedros Ghebreyesus, the Director-General of WHO.
It is noted that 42 people infected and 23 people died from the deadly disease.
However, it needs to be stored at a temperature of between -60 and -80 C, which is a challenge in DR Congo because electricity supplies are unreliable.
The East African Community (EAC) regional bloc said in a statement Friday it was on "high alert" following an Ebola outbreak in the Democratic Republic of Congo (DRC).