I read something yesterday that didn't quite explain but added something to the theory... it's not just mould ripened cheese, it is cheese with a skin.. so PERHAPS even using pasteurised milk..there is in fact another process that may make it risky.

I guess, there is like probably a 1 in 100 chance of listeria being present in even unpasteurised cheese.... BUT- do any of us take a 1 in 100 risk!!! Not bloody likely !! LOL