WASHINGTON (AFP/REUTERS) - The World Bank warned Wednesday that the deadly Ebola epidemic could be an unmitigated disaster for West African economies, and called for quick action to halt its spread.

"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 World Bank said in an analysis. The largest-ever outbreak could drain billions of dollars from economies in West Africa by the end of next year if the epidemic is not contained, it added.

The global development lender predicted that slow containment of the disease in Guinea, Liberia and Sierra Leone could lead to broader regional contagion.

Under the worst-case scenario, Guinea's economic growth could be reduced by 2.3 percentage points next year while Sierra Leona's growth would cut by 8.9 percentage points. Liberia would be hardest-hit, with a reduction of 11.7 percentage points next year.