Make sure you have at least TWO SD cards just incase something happens to one. I would be more worried about static and magnetic sources getting near the card/camera than (it going through) an X-ray. Try to get (good) internet access while on vacation to backup your favorite photos on the internet (so you have a backup of your backups).

Question the question. Answer the question. Question the answer...

I wish I knew what I was gonna say :oP