The swine fever epidemic has been described by scientists as the biggest animal disease outbreak we've ever had on the planet.

Given that scale it seems a bit of an understatement to talk about the butterfly effect.

That's the idea that a small event somewhere can have implications that ripple far and wide – i.e. a butterfly's wings cause a tiny atmospheric disturbance which snowballs to result in a hurricane on the other side of the world.


It is relevant in the sense that this news story still looks a distant - dramatic but far removed.

New Zealand is