The number of deaths in the Democratic Republic of the Congo's most recent outbreak exceeded 1,000 on Friday, the Congolese Health Ministry said.
The outbreak that was declared in eastern Congo in August is already the second deadliest in history, and efforts to control it have been complicated by attacks on hospitals and Ebola treatment centers and deep community mistrust.
"Every time we have managed to regain control over the virus and contain its spread, we have suffered major, major security events," said Mike Ryan, the World Health Organization (WHO) emergencies chief. "We are anticipating a scenario of continued intense transmission [of the disease]."
As of May 1, there have been 1,510 Ebola cases in North Kivu and Ituri provinces, with 994 deaths, but that number surpassed 1,000 when Congo's Health Ministry released its daily figures on Friday.
Ryan said the WHO was planning to expand vaccination with a new Ebola vaccine, in addition to a Merck vaccine that has already been given to more than 109,000 people.
Attacks on health workers
The situation has been made more difficult by dozens of rebel groups that operate in the region, and community rejection of health workers that has been driven in part by political rivalries, Ryan said.
He said 119 attacks have been recorded since January, 42 of them directly against health facilities, with 85 health workers wounded or killed.
Last month, a Cameroonian epidemiologist working with the WHO was killed during an assault on a hospital in Butembo city at the center of the outbreak.
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'Critical' funding gap
Insecurity has become a "major impediment to ensuring that we can access, engage with and serve the communities we wish to serve in Ebola control," Ryan said, adding that it slows efforts to vaccinate more than 900 people a day, as well as conduct daily checks on some 12,000 people who have potentially been exposed to the virus.
He also said there was an "urgent, critical gap" of some $54 million (€48 million) in funding for Ebola containment efforts and called for more help from the Congo and around the world.
The 2014-2016 Ebola outbreaks in West Africa's Guinea, Sierra Leone and Liberia killed more than 11,000 people.
law/sms (AP, AFP, dpa, Reuters)