Congo Ebola outbreak passes 11,000 cases as insecurity hampers response

Confirmed Ebola cases in the Democratic Republic of the Congo have passed 11,000, six months after health authorities flagged an outbreak that is now the second-worst on record and has reached parts of east, central and west Africa.

The virus behind it is the rare Bundibugyo species. No treatment or vaccine has been approved against it.

The outbreak was flagged in mid-May. On Friday, Chikwe Ihekweazu, who heads the World Health Organization's Health Emergencies Programme, said the response had produced encouraging signs, with cases falling in Bunia, a town in eastern Congo that was an early hotspot.

The pattern has since shifted, he said.

"What we have seen now is the emergence of cases in more rural and more difficult-to-reach areas," Ihekweazu said. "The biggest challenge the response faces right now is the rising insecurity."

WHO data count 80 attacks on health sites and health workers since the response began.

Médecins Sans Frontières, the French medical charity, has been more downbeat about the six months of work. It says supplies are missing and the virus is still spreading out of control.

Julien Harneis, the UN's special Ebola coordinator, answered that criticism by describing the size of the operation.

"The area of operation is vast, just unimaginable vast," Harneis said. "But 80 percent of the time, and across this vast area, we're able to operate."

The caseload puts the outbreak behind only the 2014-2016 West African epidemic in the record books, and the spread across three regions of the continent has drawn in health agencies well beyond Congo's borders. Bundibugyo was first identified in Uganda in 2007, and the absence of licensed countermeasures has left responders relying on contact tracing, isolation and supportive care in areas where fighting has repeatedly cut access.

Congo's health system has faced concurrent emergencies in the east for years, and the 80 recorded attacks on health workers and facilities have forced repeated suspensions of vaccination and treatment teams in the zones where the virus is now appearing.