If several West African countries fail to contain the deadly outbreak of Ebola in time, it could have "catastrophic" consequences for their economies to the tune of billions of dollars, the World Bank said in an analysis on Wednesday.

"If the virus continues to surge in the three worst-affected countries - Guinea, Liberia, and Sierra Leone - its economic impact could grow eight-fold, dealing a potentially catastrophic blow to the already fragile states," the bank said.

The worst imaginable scenario would see Guinea's economic growth stunted by 2.3 percentage points next year, while Sierra Leone would watch its growth be slashed by 8.9 percentage points.

But the hardest hit would be Liberia, with its growth reduced by 11.7 percentage points.

Perhaps counterintuitively, the biggest costs would not stem from infections but loss of tourism and trade revenues as people around try to avoid contact with the affected states.

"The largest economic effects of the crisis are not as a result of the direct costs … but rather those resulting from aversion behavior driven by fear of contagion," the World Bank said.

However, the analysis found that the economic costs could be tempered if swift national and international responses succeed in containing the epidemic and mitigating such "aversion behavior."

The Ebola outbreak in West Africa has so far claimed more than 2,400 lives this year. The analysis came at a time when the US has said it will dispatch thousands of military personnel to assist health care workers in West Africa.

sri/cjc (World Bank, Reuters)