GENEVA — The World Health Organization said Friday that while the ongoing Ebola outbreak in Congo is of "deep concern," the situation does not yet warrant being declared a global emergency.

Following a meeting of its expert committee, the UN health agency called for efforts to be redoubled to stop the deadly virus, noting that the recent spike in Ebola cases raises the risk of spreading to other countries.

The outbreak announced on Aug 1 has become the second-deadliest in history, behind the West African one from 2014 to 16 that killed more than 11,300 people. Congo's health ministry on Thursday reported 1,206 confirmed and probable cases, including 764 deaths.

Ahead of the WHO announcement, a top Red Cross official said he was "more concerned than I have ever been" about the possible regional spread of Ebola.

Emanuele Capobianco, head of health and care at the International Federation of Red Cross and Red Crescent Societies, cited Congolese health ministry data showing 40 new cases over two days this week. He called that rate unprecedented in this outbreak.

To be designated a public health emergency of international concern, a situation must be "serious, unusual or unexpected," threaten to infect other countries and require "immediate international action."

The outbreak is occurring close to the borders of Uganda and Rwanda, with South Sudan not far away.

This outbreak has been like no other. Capobianco cited lack of trust about Ebola treatment in the community, which had never faced an outbreak of the virus before, and insecurity caused by rebel groups that has hurt aid efforts.

Trish Newport, Doctors Without Borders' representative in Goma, a major crossroads city close to the outbreak, said ahead of the WHO announcement that declaring a global emergency wouldn't necessarily help stop the epidemic.

"Bigger is not necessarily better," she said. Doctors Without Borders is calling for patients to be treated in existing health centers rather than Ebola-specific clinics: "It's very clear that people do not like or trust the Ebola centers and they are not coming to be treated."

Newport said 75 percent of new Ebola cases have no obvious link to previous patients, meaning that officials have lost track of where the virus is spreading.

Previous global emergencies have been declared for the 2014 Ebola outbreak in Sierra Leone, Liberia and Guinea, the emergence of Zika virus in the Americas and the international attempt to eradicate polio. WHO was criticized for not declaring the 2014 Ebola outbreak an international emergency until nearly 1,000 people had died and the disease had spilled across borders.

Emergency declarations almost always boost global attention and donor funding. In recent weeks, WHO has noted it is woefully short of the $148 million it says is needed to fight Ebola for the next six months. It had received only $74 million as of mid-March.

Tariq Riebl, who is based in a current Ebola hot spot, Butembo, for the International Rescue Committee, said a major obstacle to stopping the outbreak is that officials are simply unaware of how many Ebola cases there are.

"We're discovering people when it's way too late," he said, noting numerous cases were buried in secret and never reported to authorities. "Given the average number of cases we're seeing now, this is not going to be over for at least another six months or more."

AP