Well, because lots of questions had been raised about the toxicity of the drug, which is very serious.

The concern around probable questions, which in a sense have been hidden, will grow around the world and the matter is critical, the reason we are doing all this is so we can respond correctly to what is reported to be a major catastrophe on the African continent.

If you sit in a position where decisions that you take would have a serious effect on people, you can't ignore a lot of experience around the world which says this drug has these negative effects.

It wouldn't sit easily on one's conscience that you had been warned and there could be danger, but nevertheless you went ahead and said let's dispense these drugs.

We've had a long wrangle with the pharmaceutical industry about parallel imports, and what we were saying is we want to make medicines and drugs as affordable as a possible to what is largely a poor population.

I get a sense that we've all been educated into one school of thought. I'm not surprised at all to find among the overwhelming majority of scientists, are people who would hold one particular view because that's all they're exposed to.