Possible Duplicate:
What precautions should I take when taking a camera into humid conditions?

I'm used to shooting in cool dry climates. I recently took a trip to Central America. Every time I went outside from a building with AC I would get extreme lens fog. I tried to warm the lens as quickly as possible by putting it in my armpit. I was wondering what the pros who shoot in these environments do.

Also, should I worry about mold now? What should I do to care for my lenses in these situations?

I have a Nikon 24-70mm f/2.8G ED AF-S and A Nikon 70-200mm f/2.8G ED VR II AF-S Nikkor Zoom Lens. This should make a difference as I think the 70-200mm is self contained where the 24-70mm sucks air in from the environment when zoomed.