Among the reasons the United Nations agency cited in internal deliberations: worries that declaring such an emergency — akin to an international SOS — could anger the African countries involved, hurt their economies or interfere with the Muslim pilgrimage to Mecca.
Those arguments struck critics, experts and several former WHO staff as wrong-headed.
"That's like saying you don't want to call the fire department because you're afraid the fire trucks will create a disturbance in the neighbourhood," said Michael Osterholm, a prominent infectious diseases expert at the University of Minnesota.
In public comments, WHO Director-General Dr. Margaret Chan has repeatedly said the epidemic caught the world by surprise.
"The disease was unexpected and unfamiliar to everyone, from (doctors) and laboratory staff to governments and their citizens," she said in January. Last week, she told an audience in London that the first sign that West Africa's Ebola crisis might become a global emergency came in late July, when a consultant fatally ill with the disease flew from Liberia to a Nigerian airport.
But internal documents obtained by AP show that senior directors at the health agency's headquarters in Geneva were informed of how dire the situation was early on and held off on declaring a global emergency. Such an alert is meant to trigger a surge in outside help, or, as a WHO document put it, "ramps up political pressure in the countries affected" and "mobilizes foreign aid and action."
When WHO experts discussed the possibility of an emergency declaration in early June, one director viewed it as a "last resort."
The delay in declaring an emergency was one of many critical problems that hobbled the agency's ability to contain the epidemic. When aid agency Doctors Without Borders warned Ebola was spiraling out of control, WHO contradicted it, even as WHO's own scientists called for backup. When WHO did send staffers to West Africa, they were of mixed calibre. Fellow responders said many lacked Ebola experience; one WHO consultant who got infected with Ebola broke his own agency's protocol, putting others at risk and getting WHO kicked out of a hotel, the AP found.
In an email Thursday, WHO said: "People often confuse the declaration of a Public Health Emergency of International Concern with our operational response. It is very different. WHO mounted a strong operational response a year ago when we were notified the outbreak was Ebola."
WHO is the only agency with the authority to lead a global response to health crises, by providing medical, laboratory and other support when there are outbreaks of unusual or new diseases. Its handling of the Ebola epidemic has been roundly criticized and led to a new call for reforms. The vacuum of leadership at WHO was so damaging the U.N. created the Mission for Ebola Emergency Response to take over the overall fight against the disease.
Dr. Sylvie Briand, head of the pandemic and epidemic diseases department at WHO, acknowledged that her agency made wrong decisions but said postponing the alert made sense at the time because it could have had catastrophic economic consequences.
"What I've seen in general is that for developing countries it's sort of a death warrant you're signing," she said.
As Ebola continued to spread in the summer, the situation on the ground grew increasingly desperate, with only a fraction of the needed treatment beds available in Liberia and Sierra Leone. Some regions didn't even have enough soap and water; patients were literally dying outside the gates of Ebola clinics as foreign mine workers evacuated and neighbouring countries restricted travel.
By the time WHO declared an international emergency, nearly 1,000 people were already dead. Overall, more than 10,000 are thought to have died in the year since the outbreak was announced.
Chan, the WHO leader, declined interview requests with AP for this story. But Dr. Bruce Aylward, WHO's top Ebola official, said labeling the Ebola outbreak a global emergency would have been no magic bullet.
"What you would expect is the whole world wakes up and goes, 'Oh my gosh, this is a terrible problem, we have to deploy additional people and send money,'" he said. "Instead what happened is people thought, 'Oh my goodness, there's something really dangerous happening there and we need to restrict travel and the movement of people.'"
Former WHO doctor Matthieu Kamwa said that logic doesn't fly. Kamwa, who worked as the agency's representative to the Democratic Republic of Congo during a 2008 Ebola outbreak, said sounding the alarm sooner would have saved lives.
"People died because things were not done," he said.
'THE TIP OF AN ICEBERG'
WHO announced the discovery of Ebola in Guinea on March 23, when it posted a two-sentence update on its website saying a "rapidly evolving outbreak" had been confirmed after months of mysterious deaths in the nation's forest region and capital city, Conakry. The virus typically overpowers the immune system, causing leaks in blood vessels that can lead to organ failure and shock. There is no licensed treatment or vaccine and the death rate can be as high as 90 per cent.
The signs this was no ordinary outbreak were there from the beginning, and many are recorded in a memo sent to WHO's Africa director on March 25: The virus had never been seen in Guinea before; health workers were dying, panic was setting in and reports of infections had already come in from neighbouring Liberia and Sierra Leone.
Its spread to Conakry was particularly disturbing.
"From the start we were very worried about cases in the capital," said Briand, the WHO official. "We told ourselves: 'From the capital it can go elsewhere.'"
In mid-April, by which point there had been at least 100 deaths in Guinea, an experienced Ebola expert with WHO's Africa office wrote to a Geneva staffer saying the situation had taken a critical turn: many health workers at the capital's Donka Hospital had been exposed to the virus.
"What we see is the tip of an iceberg," said Jean-Bosco Ndihokubwayo. The scientist requested the help of half a dozen veteran outbreak responders, writing in all-caps in the email's subject line: "WE NEED SUPPORT."
WHO official Stella Chungong said she was very worried, warning in an email that terrified health workers might abandon Donka Hospital and — equally alarming — new Ebola cases were coming out of nowhere.
"We need a drastic ... change (of) course if we hope to control this outbreak," she said.
WHO dispatched a top Ebola expert, Pierre Formenty, to the region. But many of the other managers sent to Conakry "had no idea how to manage an Ebola epidemic," according to Marc Poncin, who was mission chief in Guinea for Doctors Without Borders, also known by its French acronym MSF.
In public, WHO downplayed concerns. Spokesman Gregory Hartl told reporters in early April that "this outbreak isn't different from previous outbreaks." In a Twitter message sent by Hartl — and preserved by Britain's ITV News — he is shown asking: "You want to disrupt the economic life of a country, a region (because) of 130 suspect and confirmed cases?"
The news kept getting worse throughout April. Formenty said teams in Conakry had seen patients pop up all over the city with no known link to other cases.
"This means there is one part of the epidemic that is hidden," he wrote later in an internal trip report. "The Ebola outbreak could restart at any time."
'OVERWHELMED WITH OUTBREAKS'
As the epidemic spread, WHO struggled with competing crises.
In some ways the World Health Organization is small — its roughly 7,000 employees make it less than half the size of the U.S. Centers for Disease Prevention and Control — but its responsibilities are wide-ranging. Among other things, it monitors some 800 outbreaks every year. Most don't make international headlines.
By mid-2014, several had.
The first was polio, which came back from the brink of extinction to claw its way into conflict zones such as Syria. Its rise was labeled an international health emergency in May. The second was the baffling Middle Eastern Respiratory Syndrome, or MERS, which had sickened nearly 700 people and killed 204, mostly in the Arabian peninsula, by early June.
It was around that time that West Africa's Ebola epidemic surpassed the previous largest outbreak, in Uganda, where it infected 425 people in 2000 and killed about half.
The triple threat came at a time of steeply reduced budgets for WHO following the 2008 financial crisis. Cuts have continued since; its outbreak department shrank by about 20 per cent in 2013.
At a June 2 meeting in Geneva, scientist Stephane Hugonnet warned that the agency was "overwhelmed with outbreaks."
In Africa, the true reach of Ebola was being obscured by Guinea's Ministry of Health, which only shared information on confirmed cases and deaths, according to WHO documents. That was a problem because refusing to report suspect and probable cases meant the world wasn't getting an accurate picture of the epidemic.
One alleged motivation was mining. Guinea has the world's largest reserves of bauxite, for example, and the mineral is its main source of foreign currency. Guinean officials' insistence on only reporting confirmed cases was intended to "minimize artificially the magnitude of the Ebola outbreak to reassure expatriates working in the mining industry," Formenty, the WHO Ebola expert, wrote in another trip report.
Another issue was the hajj in October. If Saudi Arabia further restricted travel in the wake of the outbreak, that could become a political liability for Guinea, an overwhelmingly Muslim country.
Guinean government spokesman Albert Damantang Camara said Thursday that officials in Conakry never tried to hide the scope of the outbreak, but WHO official Briand said the dispute spilled out publicly when the Guinean government criticized WHO for publishing conflicting figures.
"They were not happy," she said. In a memo sent to Chan days later, WHO officials noted the Guinean authorities interpreted the discrepancy between WHO and Guinean figures "as a threat to their credibility."
Meanwhile, WHO employees wondered whether headquarters should be doing more. On June 4, scientist Lucien Manga wrote to Briand to tell her senior staff in Africa had proposed declaring the Ebola outbreak a global emergency.
"What do you think and what is your advice?" Manga asked in an email.
In a response tapped out over her iPhone the following day, Briand argued against the idea, saying it wouldn't help control the epidemic and might harm the countries involved.
"It may be more effective to use other diplomatic means for now."
On June 10, Briand, her boss Dr. Keiji Fukuda and others sent a memo to WHO chief Chan, noting that cases might soon pop up in Mali, Ivory Coast and Guinea Bissau. But it went on to say that declaring an international emergency or even convening an emergency committee to discuss the issue "could be seen as a hostile act."
Declaring an international emergency is no guarantee of ending an outbreak but it functions as a kind of a global distress call.
"It's important because it gives a clear signal that nobody can ignore the epidemic anymore," said Dr. Joanne Liu, MSF's international president.
In a meeting at WHO headquarters on July 30, Liu said she told Chan, "You have the legitimacy and the authority to label it an emergency...You need to step up to the plate."
After WHO declared the international emergency. U.S. President Barack Obama ordered up to 3,000 troops to West Africa and promised to build more than a dozen 100-bed field hospitals. Britain and France also pledged to build Ebola clinics; China sent a 59-person lab team and Cuba sent more than 400 health workers.
'A DOCTOR WHO SHOULD KNOW BETTER'
WHO and MSF often work in tandem but are sometimes at odds over everything from epidemic response to vaccination drives. The tensions that flared over Ebola highlighted some of the U.N. agency's weaknesses — including a failure to lead.
WHO did send reinforcements, including doctors, lab experts and logisticians — an "unprecedented" deployment, Chan said in September. Many were praised by fellow responders, but, in the initial stages at least, there were problems with consistency.
"It's not that we don't have competent people in Africa," said Oyewale Tomori, a former WHO staffer who now serves on the agency's Ebola Emergency Committee. "It's that they never get to a position where they can act."
He said one problem was a tendency within WHO to reward those who deferred to local authorities.
That's an issue that came up in Guinea, where the Doctors Without Borders chief there, Poncin, complained that WHO officials kept contradicting his group's warnings, something he said pleased a government that "didn't want to frighten investors."
There were personnel issues elsewhere.
In Liberia, MSF's Lindis Hurum said she sent a letter complaining about a WHO consultant who was proposing "completely unrealistic" treatments.
In mid-August, a Senegalese scientist working for WHO caught Ebola while working in Sierra Leone. At the time, staff with MSF, WHO and other aid organizations were all staying at the Luawa Resort Hotel in Kailahun, a safari lodge of bungalows with shared kitchens and public spaces.
But instead of checking into a treatment centre — the very clinics where health workers were desperately trying to persuade people with Ebola to seek help — he confined himself to his hotel room, and arranged for his own tests outside the clinic, according to MSF emergency co-ordinator Ewald Stals, who was there at the time.
"We were pretty shocked that he was still at the hotel," Stals said. "You would expect more mature and responsible behaviour from a doctor who should know better."
Stals said two other suspect cases in the hotel appeared within hours: A cleaning lady and a handyman. Though both tested negative, Stals said the incidents were enough to spook many of the MSF staffers; 14 of the 22 deployed there left Kailahun.
"We really struggled to keep the (Ebola clinic) open," Stals said. "It meant we had to run the treatment centre with eight people instead of 22."
The Ebola-infected WHO scientist, who later recovered, could not be reached for comment.
The experience soured MSF on sharing lodgings. Others at the hotel, including the CDC and a mobile lab from Canada, also left. But WHO refused to vacate the hotel until a phone call between the two agencies' top leaders resolved the stand-off.
During the call, Chan asked Liu if MSF could curb its public criticisms of the U.N. agency.
"I said, 'I'm giving you a huge favour by not bringing up this story," Liu said.
"A SINKING SHIP"
The World Health Organization has pledged to reform itself, but past experience suggests that's unlikely.
Reform proposals have been kicking around since the mid-1990s at least. In the wake of the 2009 swine flu pandemic, a major review suggested, among other things, a $100 million crisis fund and an emergency health workforce. The ideas came to naught but have been revived following the Ebola crisis.
"It's very much reshuffling the deck chairs on a sinking ship," said Kelley Lee, an academic and author of a book on WHO.
Infectious diseases expert Osterholm said the global health agency isn't the only one to be blamed and that the entire world failed to respond quickly enough to stop Ebola from becoming a humanitarian disaster.
"The global health response system is broken," he said. The WHO member countries don't seem willing to overhaul the agency, leaving the world dangerously unprepared to deal with future health crises.
"What happens if MERS blows up or there's an Ebola-like event in East Africa?" he asked. "I'm not sure WHO has a plan for that."
Cheng also reported from London. Satter also reported from London and Brussels. Boubacar Diallo in Conakry, Guinea contributed to this report.
Cheng can be reached at: http://twitter.com/mylcheng
Satter can be reached at: http://raphae.li
An interactive containing a selection of internal emails and documents from WHO illustrating the agency's decision-making in the Ebola crisis is available at: http://interactives.ap.org/specials/interactives/_documents/who-ebola/