The World Health Organization (WHO) has received less than half the funding it needs to fight the Ebola outbreak in eastern Democratic Republic of Congo, a WHO official said on Tuesday, urging donors not to abandon the country at a critical stage of the epidemic. 

The global health agency has received about 40% of its $115-million appeal to tackle the Bundibugyo outbreak, for which there is no proven treatment or vaccine. At least 1 926 people have been infected and 702 have died, government data show.

"This outbreak requires resources that match the scale of the challenges that we are facing. And this is not a burden DRC can be allowed to carry alone," Chikwe Ihekweazu, head of the WHO's Health Emergencies Programme, told reporters in Geneva after a visit to the worst-hit province of Ituri.

Ihekweazu said the response had reached a critical point, with intensified efforts needed to detect and isolate patients after cases spread this week to two new provinces.

"It's a bit like a marathon. You can't give up after the first lap or the second. You just have to keep pushing even when you're getting tired and exhausted," he said.

He repeated estimates that the true number of Ebola cases in Congo is at least double, and possibly over four times, the official tally.