The Ebola outbreak could have a catastrophic impact on the economies of Guinea, Liberia and Sierra Leone, the World Bank says.
The organisation says the economic impact of the virus could “grow eight-fold” in the “already fragile states”.
However, it says the economic cost can be limited if the epidemic – and the accompanying fear – is contained by a fast global response.
The Ebola outbreak in West Africa has killed 2,461 people this year.
Earlier on Wednesday, US President Barack Obama called the region’s Ebola outbreak “a threat to global security”, as he announced a larger US role in fighting the virus.
The world was looking to the US, Mr Obama said, but added that the outbreak required a “global response”.
The measures announced included ordering 3,000 US troops to the region and building new healthcare facilities.
The announcement came as UN officials called the outbreak a health crisis “unparalleled in modern times”.
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