More than 10,000 have died and at least 24,000 have been infected since the epidemic broke out in Guinea in December 2013.
The three-month delay in its official recognition has been blamed for its rapid spread to neighbouring Sierra Leone and Liberia, while other west African countries such as Nigeria and Mali also suffered fatalities.
The World Health Organisation has been criticised for its slow response, while governments and charities have admitted they could have done things differently.
Medecins Sans Frontieres/Doctors Without Borders (MSF), which had emergency teams on the ground in Guinea before ebola was even officially declared, said despite raising the alarm the epidemic was out of control, “it was like shouting into a desert”.
The organisation has released a report to mark the anniversary, which it dedicated to the 500 healthcare workers who have died fighting ebola, including 14 involved with the charity itself.
It said there was little sharing of information between the affected countries at first, while their governments tried to downplay the problem for fear of causing panic and driving visitors and investors away.
MSF director Christopher Stokes said: “The ebola outbreak has often been described as a perfect storm: a cross-border epidemic in countries with weak public health systems that had never seen ebola before.
“Yet this is too convenient an explanation. For the ebola outbreak to spiral this far out of control required many institutions to fail. And they did, with tragic and avoidable consequences.”
Meanwhile, Oxfam has said more efforts should have been put into engaging the community rather than focusing exclusively on medical treatment when the epidemic first broke out.
It said governments and aid agencies, including Oxfam, got the balance wrong and preventative measures should have been explored rather than purely technical solutions such as more beds, medical workers and medicines.
Sue Turrell, head of Oxfam’s ebola response, said: “We are still a long way from getting to zero cases, but the direction of travel is positive and we cannot take the foot off the accelerator.”
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