Winnipeg has a sophisticated virology lab, and Mexico has been testing samples for H1N1 (swine flu) there.
Here are some recent flights:
(return leg, arrival was via Atlanta, probably to stop at the CDC lab there)
flightaware.com/live/flight/MAF6 … /CYWG/MMMX
flightaware.com/live/flight/MAF6 … /MMMX/CYWG
Here’s a story about the testing: winnipegfreepress.com/specia … 45312.html