Picked up a cold on my way home from the DR
I just got back from 10 days vacation, with a cold, which I caught somewhere between the Dominican Republic and Victoria.
The "Pandemic Spread and Airline Travel" map from Infonaut's Map of the Moment shows a map image from NASA, showing flight patterns over the USA.
Watch this video to see a 24 hour view of the air traffic over the Continental US – you can see how infectious diseases can be spread, quickly.