(AGI) Rome, July 4 - The Ebola virus has killed 467 in anepidemic in Guinea, Sierra Leone and Liberia. Guinea reported303 deaths out of 413 cases in March. In Sierra Leone 99 peopledied out of 239 infected. In Liberia the figure was 65 dead outof 107 cases. The World Health Organization said the mortalityrate was 61.5 percent. Drastic action was needed to contain theepidemic, it said. Symptoms may appear three weeks after thevictims are infected but there is no effective treatment. .