In the age of alerts

In When warnings become a scare, the Christian Science Monitor examines an interesting dilemma of our time:

Just as scientists are pursuing early-warning systems for everything from earthquakes to hurricanes, public-health officials are monitoring potential epidemics as never before.

There's just one problem. Better detection has spawned several false alarms over the past few decades, potentially undermining the credibility of warnings. That dynamic is pushing governments and news media into unfamiliar territory.

How should they warn about something that might never occur? Does talking about an uncertainty help - or simply raise unnecessary fears?