The World Health Organization said on Wednesday the risk of global spread of the Ebola virus in Congo and Uganda is high at national and regional levels, but low at the global level.

The risk assessment came as the leader of the WHO team in Congo said the outbreak, which has led to 134 suspected deaths, could last at least another two months as aid efforts intensified on to stem the spread.

WHO has declared the Ebola outbreak a public health emergency of international concern, requiring a coordinated response. On Tuesday it expressed concern over the “scale and speed” of the outbreak.

Worried residents have reported rising prices for face masks and disinfectants following the outbreak of the rare type of Ebola, known as the Bundibugyo virus, which spread undetected for weeks following the first known death as authorities tested for a more common type of came up negative, health experts and aid workers said. There are no approved medicines or vaccines for the Bundibugyo virus.

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

“We know that the scale of the epidemic is much larger,” he said. “We expect those numbers to keep increasing.”

Congo was expecting shipments from the United States and Britain of an experimental vaccine for different types of Ebola, developed by researchers at Oxford, Jean-Jacques Muyembe, a virus expert at the National Institute of Biomedical Research, told reporters on Tuesday.

“We will administer the vaccine and see who develops the disease,” he said.

Health experts said that the delayed detection of the virus, large movements of population in the affected areas, as well as the preexisting humanitarian crisis, complicated the response. Parts of eastern Congo are in the hands of armed rebels, hampering the delivery of aid.

Congo said the first person died from the virus on April 24 in Bunia, but the confirmation did not come for weeks. The body was repatriated to the Mongbwalu health zone, a mining area with a large population.

“That caused the Ebola outbreak to escalate,” said Congo’s Health Minister Samuel Roger Kamba.

Dr. Anne Ancia, the head of the WHO team in Congo, said authorities still haven’t identified “patient zero.” There was a long road ahead, she said, adding that cuts in funding had “a marked detrimental effect on humanitarian actors.”

U.S. Secretary of State Marco Rubio told reporters on Tuesday that the Trump administration would “lean into” Ebola response efforts with a priority on funding 50 emergency clinics in affected areas. The U.S. has so far contributed $13 million to the effort and Rubio said more would be coming.

In Bunia, the site of the first known death, schools and churches remained open on Wednesday, and some residents were wearing masks in the street. Residents said that masks have become harder to find and that some disinfectants previously sold for 2,500 Congolese francs now cost up to 10,000 francs ($4.4).

“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. “We have to protect ourselves to avoid this epidemic.”

Trish Newport, emergency program manager from Doctors Without Borders aid group said that her team in Bunia identified suspected cases over the weekend in the Salama hospital, where there is no isolation ward. They tried, unsuccessfully, to place them in another health facility in Bunia.

“The team called around to other health facilities to see if they had isolations,” she said. “Every health facility they called said, ‘We’re full of suspects cases. We don’t have any space.’ This gives you a vision of how crazy it is right now.”

In Mongbwalu, the town at the epicenter of the current outbreak, the border with Uganda remains open and gold mining activities continue, said Chérubin Kuku Ndilawa, a local civil society leader.

“There’s no panic; people are continuing their normal lives, but they’re also starting to spread the word,” said Ndilawa.

Efforts to contain the outbreak have been hindered by a lack of handwashing stations in public areas, said Ndilawa.

Dr. Didier Pay, a former director of the Mongbwalu General Hospital, said his clinic was treating around 30 Ebola patients. He said a student from the local medical technology institute had died on Wednesday morning.