Ebola is a truly frightening disease, with a fatality rate as high as 95 per cent (although the death rate in the current outbreak in West Africa is only 55-60 per cent). At the moment, it is largely confined to a heavily forested inland area where the borders of Liberia, Sierra Leone and Guinea meet, although cases have already appeared in the capital cities of all three countries.
It could get much worse. If ebola successfully made the jump to a more prosperous, densely populated country like Nigeria, whose citizens travel all over the world, the current 800 recorded deaths could become 8000 or 80,000, or even more. And the worst of it is that there is no effective vaccine or treatment for ebola.
Let me rephrase that. There is no approved vaccine or treatment for ebola. There are candidates, some of which have shown promising results when tested on non-human primates. But they haven't gone through the full testing process that is necessary before they are approved for human use, because nobody was willing to pay for it.
The normal procedure in the United States, home to more than half of the world's major drug companies ("Big Pharma"), is that basic research for new drugs may be paid for by government grants or even by private philanthropy (like Bill Gates's $200 million donation for research on a malaria vaccine), but the work of bringing the drugs to market is left to the commercial companies. All too often, they simply can't be bothered.
It costs hundreds of millions of dollars to take a drug through the whole approval process and put it on the market. That's worthwhile if the drug will then sell at a high cost and be used regularly over long periods of time: a drug that fights "rich people's diseases" like cancer or heart disease, say, or even something like Viagra. But a one-shot vaccine that would mainly be used by poor Africans will never make a profit, so it is ignored.