Well, temperature DOES play a role in killing parasite eggs. 85* and higher for several days in a row will kill eggs.
http://www.ker.com/library/advances/439.pdf
. Over a wide temperature range (45° F to 85° F), the rate of larval development is directly
proportional to environmental temperature. At lower temperatures, hatching and
development may require several weeks or months, whereas eggs can hatch and
develop into third stage larvae in three to five days when ambient temperatures are in
the high 70s (F). Beyond both temperature extremes, eggs either cannot hatch if it is
too cold, or larvae develop rapidly but soon die when it is too hot.
Moisture absolutely does play a role in their survival. Hot and dry can kill pretty quickly.

I sure wish I could find the source I found at one point that said you could be looking at possible contamination for up to 10 years, and if that said anything about which parasites specifically.