JOHANNESBURG | Congo’s deadly Ebola outbreak has become the second largest in history, behind the devastating West Africa outbreak that killed thousands a few years ago, the World Health Organization said Thursday.

WHO’s emergencies chief, Dr. Peter Salama, called it a “sad toll” as Congo’s health ministry reported the number of cases has reached 426. That includes 379 confirmed cases and 47 probable ones. So far this outbreak, declared on Aug. 1, has 198 confirmed deaths, with another 47 probable ones, Congo’s health ministry said.

FILE – In this file photo dated Sunday, Sept. 9, 2018, health workers walk with a boy suspected as having the Ebola virus at an Ebola treatment centre in Beni, Eastern Congo. According to a WHO announcement Thursday Nov. 29, 2018, Congo’s deadly Ebola outbreak is now the second largest in history, and predicted the outbreak will last at least another six months before it can be contained. (AP Photo/Al-hadji Kudra Maliro, FILE)
FILE – In this file photo dated Sunday, Sept. 9, 2018, health workers walk with a boy suspected as having the Ebola virus at an Ebola treatment centre in Beni, Eastern Congo. According to a WHO announcement Thursday Nov. 29, 2018, Congo’s deadly Ebola outbreak is now the second largest in history, and predicted the outbreak will last at least another six months before it can be contained. (AP Photo/Al-hadji Kudra Maliro, FILE)

Attacks by rebel groups and open hostility by various wary locals have posed significant challenges to health workers that Ebola experts say they’ve never been seen before. Many venture out on critical virus containment missions only accompanied by U.N. peacekeepers in areas where gunfire echoes daily.

Salama this month predicted that the outbreak in northeastern Congo will last another six months before it can be contained, at the very least. West Africa’s Ebola outbreak killed more than 11,000 people from 2014 to 2016.

Each day, reports by health organizations note one new difficulty after another in this latest outbreak, even as their work sets milestones that have given new hope in the fight against one of the world’s most notorious diseases.

More than 37,000 people have been vaccinated for Ebola, and Congo has begun the first-ever trial to test the effectiveness and safety of four experimental Ebola medications. And yet the risk of Ebola spreading in so-called “red zones” — areas that are virtually inaccessible because of the threat of rebel groups — is a major concern in containing this outbreak.

“This tragic milestone clearly demonstrates the complexity and severity of the outbreak. While the numbers are far from those from West Africa in 2014, we’re witnessing how the dynamics of conflict pose a different kind of threat,” said Michelle Gayer, senior director of emergency health at the International Rescue Committee.

In a major concern for health workers, many new cases have been unconnected to known infections as the insecurity complicates efforts to track contacts of those with the disease.

The alarmingly high number of infected newborns in this outbreak is another concern, and so far a mystery. In a separate statement on Thursday, WHO said so far 36 Ebola cases have been reported among newborn babies and children under 2.

As the need for help in containing the outbreak grows, two of the world’s most prominent medical journals this week published statements by global health experts urging the Trump administration to do more.

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