GENEVA • World Health Organisation (WHO) outgoing chief Margaret Chan has defended her legacy, insisting the world had become better prepared to face health emergencies such as Ebola on her watch.

In her final address to WHO's member states, she acknowledged that mistakes had been made during her decade at the helm, but stressed that while "we falter sometimes... we never give up".

"The world is better prepared, but not nearly well enough," she told some 4,000 delegates from WHO's 194 member countries at its annual assembly in Geneva on Monday.

Dr Chan, whose successor would be elected yesterday, presented a range of achievements she insisted dispelled "the frequent criticism that WHO has lost its relevance".

She had reason to be on the defensive: During her tenure, WHO faced crushing criticism for its handling of several health emergencies, but none more than the West Africa Ebola epidemic that killed more than 11,300 people between late 2013 and early last year.

"The outbreak took everyone, including WHO, by surprise," Dr Chan said.

"WHO was too slow to recognise that the virus, during its first appearance in West Africa, would behave very differently than during past outbreaks in central Africa."

But she pointed to a wide range of reforms initiated while the crisis raged, saying the United Nations health agency had "made quick course corrections", brought the outbreak "under control, and gave the world its first Ebola vaccine".

Dr Chan told the delegates that "history will judge" if she had succeeded.

US Health Secretary Tom Price said the next WHO head must continue overhauling the agency, "taking a clear-eyed view of what needs to change".

All three candidates vying to replace Dr Chan have vowed to push ahead with reforms.

They include former Pakistani health minister Sania Nishtar and WHO insider David Nabarro, a British doctor and diplomat who has spent two decades inside the UN system.

Ethiopia's former foreign and health minister Tedros Adhanom is also on the list, aiming to become the first African to hold the post.

AGENCE FRANCE-PRESSE