Experience I guess...
Anything that doesn't disfigure half the European population or covers them in boils, and then kills off most of the victims is not worth talking about. The general feeling here is best expressed as: 'Meh'.
Yep thats how it is round here!
We've had to deal with Foot and Mouth epidemic so it'll have to be far worse than that before we panicked lol!
I was stuck in a city when a child due to a typhoid epidemic, police blocked the roads out we weren't allowed to leave. No body panicked them either, as kids it was great, they closed the schools!
http://www.historyscotland.com/features/aberdeentyphoid.html