The Democratic Republic of Congo is warning that its Ebola outbreak has entered a potentially dangerous "new phase" after a case was confirmed in the northwestern city of Mbandaka.

Already, 23 people have died of Ebola in the current outbreak, and workers with the UN World Health Organization (WHO) are tracking 432 leads (.pdf link) of people who may have been exposed to the oft-deadly virus.  Most of these cases are in the remote Bikoro area.

"The reason why most Ebola outbreaks have tended to dissipate quickly is because they've mostly been in rural areas, so there haven't been many people to spread it," said Dr. Ashish Jha, director of the Harvard Global Health Institute, as quoted by the HuffPost.

The new case in Mbandaka is a man who, with another man, had travelled to and from Bikoro for a funeral.  They returned to a city of more than a million people located on the Congo River which many call "the superhighway of central Africa".  Thus, in addition to having far more people than health officials could possibly track, it is connected by river transportation to three other major urban centers with a combined population of 15 million people.

Two factors are working in favor of the health care workers:  Unlike the West African Ebola Epidemic of 2014 - 2016 which killed more than 11,300 people, WHO is on the ground and working to stop the spread of the virus. 

And this time around, there are experimental vaccines that can be used to combat Ebola.  The first batch of 4,000 doses has arrived in the DR Congo capital Kinshasa, with another 4,000 to follow soon after.