The Centers for Disease Control and Prevention hopes to send experts to Congo in the next few weeks to train international and local personnel in the fight against a raging Ebola outbreak that has killed nearly 600 people and is far from under control, the CDC director said Thursday in an interview.

Because of the worsening security situation, the CDC experts would not be based in the epicenter of the outbreak, in conflict-ridden parts of eastern Congo. Armed attacks against Ebola treatment centers in North Kivu province have increased in recent weeks. One attack took place hours before CDC Director Robert Redfield and World Health Organization Director-General Tedros Adhanom Ghebreyesus arrived last week as part of a WHO delegation to assess the situation on the ground. Another attack took place Thursday when an Ebola clinic was burned down by people who then set fire to the home of a local official, according to news reports.

Three CDC personnel are on temporary assignment about 200 miles south of the epicenter, in the city of Goma, the capital of North Kivu, Redfield said. If U.S. security personnel give their approval, “we’re hoping to augment that team significantly to increase that training,” Redfield said in an interview. Government sources said the CDC hopes to send as many as 10 people for the temporary training assignments.

“This is a complicated response,” Redfield said. The outbreak, now entering its eighth month, “is not under control” and is likely to last through this year and into 2020, he said. “This late in the outbreak, and half of the cases are presenting dead,” he said, an indicator that an unusually high number of infected people are not being identified when they fall ill.

When sick people don’t go for help to clinics and treatment centers, “that’s a disastrous indicator for an Ebola response,” Redfield said. “This tells you that the community is not helping us. We need the community to become a key component of the public health Ebola response.”

During his trip to Congo, Redfield said, he and the other officials arrived at an Ebola clinic Saturday hours after it had been attacked by people trying to extort money from the facility. “There were bullet holes in the windows,” he said. The police officer guarding the front was killed. Two nurses were injured. “But it didn’t stop these workers from wanting to do their jobs,” he said. But all of them, he said, raised the concern that “they don’t feel safe at work.”

Redfield spoke with The Washington Post after he and other U.S. officials testified before a Senate panel about the ongoing outbreak, which has sickened at least 932 people and killed 587. It was his first testimony before Congress since his appointment a year ago.

The U.S. assessment was far more sober than that offered by the WHO chief. Tedros told reporters Thursday in Geneva that the Ebola outbreak can be brought to an end in six months. He pointed to several locations in North Kivu where transmission of the virus has stopped, and he noted that the number of new cases had been cut in half since January, with an average of 25 new cases reported each week now compared with 50 at the beginning of the year. But he acknowledged that violence, unrest and community resistance remain challenges.

The Ebola outbreak in Congo is the most serious since a sprawling Ebola epidemic devastated three countries in West Africa between 2014 and 2016, killing more than 11,000. Ebola spreads through contact with the bodily fluids of its victims and is fatal in as many as 90 percent of cases.

Eastern Congo has been the site of some of the world’s largest-scale violence in the past quarter-century, making the effort to contain this Ebola outbreak enormously complicated. The latest armed attacks forced Doctors Without Borders, known by its French acronym MSF, to pull out of operating two of its Ebola clinics.

But some experts say the public health response is not keeping up with the escalating crisis.

Experts agree that the only way to contain the outbreak is through swift identification and isolation of all cases and monitoring of people they’ve been in contact with to make sure they can be offered an experimental Ebola vaccine. Although nearly 90,000 vaccinations have likely slowed the speed of transmission, vaccinations have not stopped it.

“A critical threshold has been crossed in recent weeks: Deliberate targeted violence is now directed at health providers,” said Steve Morrison, director of the Global Health Policy Center at the Center for Strategic and International Studies. The violence appears to be tied to many factors, including the latest disputed presidential election, he said.

“There is no Plan B,” Morrison said. “There is no high-level diplomatic activism and unlikely to be any until the outbreak spreads to external major urban centers. Something far bigger and stronger is needed, in external security, political muscle and community engagement.”

Although the CDC has deployed more than 100 personnel to the Congolese capital and neighboring countries and WHO headquarters in Geneva, its highly trained Ebola experts have not been allowed to deploy to the epicenter because of the security situation.

“We need in the field, right now, well-trained experts that have deep experience in responding to Ebola and the community resistance that often occurs during such outbreaks,” said Jennifer Nuzzo, a senior scholar with the Johns Hopkins Center for Health Security. “The U.S. government, specifically CDC, is unmatched in having this experience. We need to figure out a way to enable them to safely go into the field to meaningfully participate in the response.”

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