Ebola is wreaking havoc on three west African nations - Guinea, Liberia and Sierra Leone. The official death toll is beyond 5,000, the real victim-count is almost certainly much higher. The virus brings with it a lethal cocktail of fear, fractured communities and economic misery. Hardtalk speaks to Dr Geraldine O'Hara, a specialist in infectious diseases who is just back from a stint working with Doctors without Borders in Sierra Leone. What's the key to beating Ebola?