GENEVA: The fatal Ebola outbreak in the Democratic Republic of Congo is spreading rapidly, the World Health Organization warned Friday, despite accelerating efforts to tackle the virus.

The WHO said it was still racing to catch up with the worsening situation gripping the northeastern DRC.

"The outbreak remains serious" and is "evolving so fast", said Marie-Roseline Belizaire, the WHO Africa emergencies chief.

"However, I have seen a response that is growing stronger every day," she told reporters in Geneva, speaking from Bunia, the capital of the DRC's Ituri province, the outbreak's epicentre.

The outbreak was declared on May 15, though transmission had been going undetected for some time beforehand.

It is caused by the rare Bundibugyo strain of the virus, for which there is no vaccine or specific treatment.

There have been 896 confirmed cases so far in the DRC, including 232 confirmed deaths, with 21 new cases in the last 24 hours, according to the latest WHO update.

More than 90 percent of known cases in the DRC have been in conflict-wracked Ituri.

The outbreak has also spread to North Kivu and South Kivu provinces.

Belizaire said the epidemic was evolving so quickly that the response was racing to keep pace with the virus, which spreads by close contact and infected bodily fluids.

The number of treatment beds available for Ebola patients had gone from zero to more than 500, she said.

And surveillance teams were now investigating nearly 400 alerts and were capable of administering more than 2,000 tests a day, she added.

Belizaire also highlighted that efforts to trace contacts of known Ebola cases had ramped up, with 75 percent of all contacts now being reached.

The WHO has said 95 percent of contacts must be traced to get on top of the outbreak.

Belizaire said some people falling ill were staying at home, then going to traditional healers, before finally going to healthcare centres, delaying access to treatment.

In the DRC, 78 people have recovered after contracting Ebola, which she called a "powerful reminder that a timely diagnosis, access to quality healthcare can save lives".

Health workers killed

Belizaire said health workers were hit hard in the early stages of the epidemic.

So far, 75 healthcare workers have been infected with Ebola, of whom 17 have died, she said.

"In DRC, as we are seeing a large community outbreak, we cannot say for sure they have been infected in a health facility," she added.

"It is a really high price that the healthcare system is paying."

Belizaire said a Chinese medical team had arrived in the capital Kinshasa and would be heading to Bunia.

In neighbouring Uganda, the only other country hit, there have been 19 confirmed cases including two deaths, and 10 recovered patients.

Uganda has reported no new cases for 12 days.

Meanwhile the UN migration agency said it had done more than a million health screenings at borders and on travel corridors as part of surveillance measures aimed at detecting potential cases.

World Health Organization

Ebola spreading 'fast' in DR Congo, warns WHO