Democratic Republic of the Congo recorded its largest one-day increase of Ebola cases yesterday, as the country's deadly outbreak shows no signs of slowing.
A further 14 cases of the virus were confirmed yesterday, taking the total to 713 cases since the epidemic was declared in August.
Nine of the new cases were in Katwa, a city of a several hundred thousand people just outside Butembo.
Several other zones in this district have been hit already, and fears are growing that the disease could spread into Uganda and Rwanda.
The virus has already taken the lives of 439 people, making it the second worst outbreak in history, after the 2013-2016 outbreak in West Africa.
The health ministry said in a daily bulletin that the area near the Ugandan border has emerged as the outbreak's new epicentre.
The ministry also announced six new deaths of confirmed cases as well as the recovery of one patient.
It comes just days after health officials expressed concern about Ebola travelling south and reaching the city Goma, which sits on the border with Rwanda.
Goma has almost double the population of Butembo, meaning there is a much higher potential for the virus to spread quickly.
If Ebola does make it to the major city of Goma then 'all bets are off' for the bid to control the outbreak, one health official said earlier this week.
In preparation, the WHO and DRC's health ministry have already sent rapid response and vaccination teams to Kayina, and set up a lab in Goma as a precaution.
More than 60,000 people have been vaccinated against the virus already, in an outbreak which is the second worst in world history.
But even with
vaccinations and diagnostics and knowledge from the worst ever outbreak in 2014 - which killed 11,300 - the DRC is still struggling.
Health officials have described the DRC as 'one of the most complex settings possible',
largely been due to widespread militia violence in eastern Congo, which experts say has hampered the response from aid workers.
Health workers have been kidnapped, had to dodge bullets, been confronted by armed groups and seen treatment centres ransacked.
Mistrust
among the locals to comply with health officials has been challenging.
Experts have said people's unwillingness to come forward and be screened leads them to believe the number of cases could be even higher.
Laurie Garrett, former senior fellow of global health at think-tank Council on Foreign Relations, said cases keep 'popping up unexpectedly out of thin air' in a piece for
Foreign Policy.
Ebola can be transmitted between humans through blood, secretions and other bodily fluids of people - and surfaces - that have been infected.
With women at the forefront of care in communities in the DRC, gender disparities have meant two-thirds of Ebola patients have been women.
The country is predicted to have months more of suffering in store - at least six- before the outbreak comes to an end.
But if the disease spreads out of the north-east region, where it has so far been contained, it could rage on for even longer.