Officials are trying — and failing — to squelch a simmering Ebola outbreak in the Democratic Republic of the Congo, where the death toll passed 1,000 on Friday. The outbreak has been taking place for nearly a year.

Why it matters: The longer this outbreak goes on, the greater the likelihood of it spreading to highly populated areas within the DRC, moving beyond the country to neighboring areas or becoming endemic to the sprawling country. It is already the second-largest outbreak of the highly lethal and contagious virus on record, and officials from the World Health Organization issued new warnings Monday that they do not have the money or the security resources to fight it.

The context: This Ebola outbreak is taking place in a country that is home to an insurgency, with dozens of armed groups operating in areas where Ebola cases have been occurring. Ebola treatment centers have been attacked and destroyed, and 85 health workers have been injured or killed in 119 violent attacks since January, according to new figures from the WHO.

What's new: In a press conference early Friday, Michael Ryan, executive director of WHO’s Health Emergencies Program, said the availability of effective Ebola vaccines was not enough to stop the outbreak because of the tenuous security situation.

“We are anticipating a scenario of continued intense transmission," Ryan said.

A key task for health workers responding to the outbreak is known as contact tracing, which involves tracking down everyone an infected person came into contact with, and either vaccinating them, tracking their health, or both.

Due to community resistance and security fears, this basic epidemiological task is not being fully performed, causing many cases to be missed and new chains of transmission to be established.

A new study published this week shows the one Ebola vaccine available so far in the DRC, known asrVSV-ZEBOV and manufactured by Merck, is 97% effective. However, its effectiveness drops dramatically if it's not given at least 10 days before infection, the study found, making reliable contact tracing even more critical.

But, but, but: The WHO, despite facing long odds in getting this outbreak under control, has so far refused to declare what's known as a Public Health Emergency of International Concern, or PHEIC, which is the public health equivalent of a red alert.

WHO chief Tedros Ghebreyesus said this week that, "The world has never seen anything like this," and that his organization only has about 50% of the resources they need.

"To be honest, with conflict, high morbidity, high population density, political problems and security problems, it’s a miracle we don’t have cases spreading more," Ghebreyesus told Nature News.

The WHO has cited the lack of Ebola's spread to other countries as a reason not to declare an emergency, despite the continued, uncontrolled spread within the DRC.

"The events of the last month, including the unprecedented rise in cases, clearly indicate that the situation is getting worse and new efforts are needed," Jennifer Nuzzo, a public health expert at Johns Hopkins University, tells Axios.

She said Ghebreyesus' statements about the severity of the outbreak and obstacles facing responders, "...meets the legal definition by which a PHEIC should be declared."

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