Well if the regulatory agencies decided that they weren’t going to act then I suspect there would be a grass roots level spread of the strain anyway. This would be the worst way to use such a strain, but I don’t think it would be possible to stop this happening.

I don’t think we will get to that point. If we collect good data from the natural spread of any attenuated strain then I think the regulatory authorities will allow its use on the basis of this data.