“We think, with some of our support and modelling, the scale of the outbreak is at least two to four times the number of cases we are finding,” Dr Chikwe Ihekweazu, executive director of theWHO’s Health Emergencies Programme, told reporters in Geneva after a visit to eastern Democratic Republic of Congo.

According to the DRC’s latest official figures, the haemorrhagic fever has infected more than 1,960 people and killed more than 700 since it was detected two months ago. Cases have also been identified in neighbouring Uganda.

The WHO emergencies director added that its modelling shows the virus is spreading faster than ever seen before.

“This is now the third-largest Ebola outbreak ever, and we’ve seen the fastest growth in a single month since the outbreak started, and of all the Ebola outbreaks that we’ve managed,” Ihekweazu said.

The DRC‘s 17th Ebola outbreak was declared on 15 May after several deaths in Ituri, a mineral-rich northeastern province plagued by armed groups.

‘Deeply concerning’

Cases of Ebola, which spreads through close contact and infected bodily fluids, have so far been found in five DRC provinces, as well as in Uganda. But more than 90 percent of cases are still being detected in Ituri, Ihekweazu said.

Returning from a week-long trip to the region, the doctor said the crisis remained “deeply concerning”.

The outbreak, which is caused by the rare Bundibugyo species of Ebola, for which there is no approved vaccine or treatment, “continues to outpace the response efforts by the national authorities, international partners, including WHO, and the communities most affected”, he said.

“Perhaps the most alarming finding is that many newly reported cases are individuals who died in their communities, without ever reaching a health facility and receiving care.”

Ebola death toll in DRC and Uganda passes 200 as funding pledges fall short

Response ramps up

Ihekweazu nonetheless said he was encouraged to see a ramping up of the response.

“Treatment capacity now exceeds 700 beds and continues to increase each week; laboratory capacity has expanded dramatically… and contact follow-up rates are approaching 80 percent,” he pointed out.

He noted that: “Over the last few days, we’ve seen some of the highest numbers of new infections in a single day.”

“A few days ago, we saw over 80 cases confirmed in a single day,” he said, adding that this is however “good news”, as it shows that fewer cases are escaping detection. “It’s a sign of a maturing response.”

The United States on Monday said it was blocking American citizens in the DRC from returning to the US on commercial flights, placing recent travellers on a “do not board” list until they have spent at least 21 days in a third country.

Washington has also banned non-citizens who had travelled to the DRC, Uganda or South Sudan from entering the country.

 (with newswires)