BUNIA, Congo (AP) — Anxious healthcare workers in eastern Congo said Wednesday they are underprotected and undertrained in a rapidly spreading Ebola outbreak of a rare type of the virus in one of the world's most remote and vulnerable places.

The region has long been threatened by armed groups that control a major city where Ebola cases have now been confirmed, complicating health workers' catch-up efforts to trace the outbreak.

The World Health Organization, which noted a low risk globally, has said "patient zero" has not been found.

"It's truly sad and painful because we've already been through a security crisis, and now Ebola is here too," said Justin Ndasi, a resident of Bunia, where the first known death was announced last week after what experts say was a worrying delay in detecting the virus.

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Tons of health supplies have been airlifted to Bunia but residents said masks are harder to find and some disinfectants that previously sold for 2,500 Congolese francs (about $1) now cost four times more.

A mother watches her son 'bleeding and vomiting'

At a treatment center in Rwampara, healthcare workers in protective gear silently handled the bodies of suspected Ebola victims. Families, which traditionally wash deceased loved ones, cried and watched helplessly as workers disinfected them and placed them into coffins for secure burial sites.

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The disease struck suddenly, they said, describing a rapid deterioration after symptoms were mistaken for illnesses such as malaria.

"He told me his heart was hurting," said Botwine Swanze, who lost her son. "Then he started crying because of the pain. ... Then he started bleeding and vomiting a lot."

The Ebola virus is highly contagious and spreads in the human population through contact with bodily fluids such as vomit, blood or semen. Symptoms include fever, vomiting, diarrhea, muscle pain and at times internal and external bleeding.

WHO chief says the 'scale of the epidemic is much larger'

WHO has declared the outbreak a public health emergency of international concern, worried over its "scale and speed." The WHO chief in Congo says it could last at least two months.

The rare type of Ebola, known as the Bundibugyo virus, spread undetected for weeks following the first known death while authorities tested for another, more common Ebola virus and came up negative.

Investigations continued into where and when the outbreak started, but "given the scale, we are thinking that it has started probably a couple of months ago," said Anaïs Legand, with WHO's emergencies program.

So far, 51 cases have been confirmed in Congo's northern provinces of Ituri and North Kivu, and two cases in Uganda, WHO Director-General Tedros Adhanom Ghebreyesus said Wednesday. There are 139 suspected deaths and almost 600 suspected cases.

But "the scale of the epidemic is much larger," he said.

The London-based MRC Centre for Global Infectious Disease Analysis estimated that cases have been substantially undercounted and that the actual number could already exceed 1,000. "The true magnitude remains uncertain," it said.

This is Congo's 17th Ebola outbreak, and the WHO has said the country's health ministry has experienced staff and capacity to respond. Most outbreaks, however, were of the more common Ebola type.

Any potential vaccine is months away

Dr. Vasee Moorthy, a special adviser at WHO, said a vaccine to address Bundibugyo would not be available for at least six to nine months.

Eastern Congo already faced "immense pressure from conflict, displacement and a collapsing health system," said Dr. Lievin Bangali, senior health coordinator for the International Rescue Committee in Congo, adding that years of underfunding have weakened the response.

The outbreak highlights the effects of the Trump administration's deep cuts in foreign aid. U.S. Secretary of State Marco Rubio has said the administration set a priority on funding 50 emergency clinics in affected areas. The U.S. pledged to contribute $23 million.

Anxiety grows with little protection in affected places

In Bunia, schools and churches remain open while some residents wear masks. Elsewhere in Ituri province, suspected Ebola patients share a ward with others injured or ill at Bambu General Hospital.

A Doctors Without Borders team identified suspected cases over the weekend at Bunia's Salama hospital but found no available isolation ward in the area, said Trish Newport, an emergency program manager.

"Every health facility they called said, 'We're full of suspect cases. We don't have any space.' This gives you a vision of how crazy it is right now," she said on social media.

In Mongbwalu, where the body of the first known death was taken, the nearby border with Uganda remains open and gold mining continues, said Chérubin Kuku Ndilawa, a civil society leader.

"There's no panic. People continue with their normal lives, but they're also starting to spread the word," said Ndilawa, and noted a lack of public handwashing stations.

There were around 30 Ebola patients at Mongbwalu General Hospital, where a student from the local medical technology institute died on Wednesday, Dr. Didier Pay said.

"The patients are scattered here and there," said Dr. Richard Lokudu, the hospital's medical director. "We hope for the proper triage and isolation facilities to be installed today, and if that doesn't happen, we will be completely overwhelmed."

They are understaffed and not trained to handle suspected cases, Lokudu said, and added that if confirmed cases surge, "we have no protection."

In the Ebola-affected city of Goma, where Rwanda-backed M23 rebels are in control, the "situation is complicated," said Dr. Anne Ancia, WHO's representative in Congo.

An American with Ebola is in isolation in Germany

A U.S. national who tested positive in Congo arrived in Berlin on Wednesday and was in a special isolation ward where a "comprehensive examination" was underway, German Health Ministry spokesperson Martin Elsässer said.

Elsässer declined to comment on the condition of the patient, who has not been identified by German or U.S. authorities. The ministry later said, without elaborating, that it would take in the patient's wife and three children at the request of U.S. authorities.

A top health official in the Czech Republic said they are receiving an American doctor who was treating Ebola patients in Uganda and who is without symptoms. It was not clear whether any were infected.

Dr. Satish Pillai, incident manager for Centers for Disease Control and Prevention's Ebola response, told reporters Wednesday that the Americans were being transported in coordination with the U.S. State Department and other agencies. One patient, who is in stable condition, is now being treated in Germany, Pillai said.

Asked whether the White House played a role in the decision to move the Americans to Europe, Pillai said the decision was based on conditions on the ground and the need to mobilize rapidly.

Associated Press writers Jamey Keaten in Geneva; Jean Yves Kamale in Kinshasa, Congo; Wilson McMakin in Dakar, Senegal; Devi Shastri in Milwaukee, WI; Karel Janicek in Prague and Geir Moulson in Berlin contributed to this report.