Cats don't generally have parasites and most would be different. But regardless of what - or when - something was in there you need to thoroughly clean and sterilize/sanitize. I assume it is a screen cage? I would take all the panels apart, use a high power spray (any good garden sprayer attachemnet) to loosen anything. Then soak, or thoroughly wipe down all the panels, hardware, etc. with a bleach/water solution (1 part bleach to 10 parts water ). You can put it in a spray bottle so it will get into crevices. Then rinse well and let it air dry (if possible. if you live in a warm region keep it outside for a few days in the sun). You might then want to give it a once over with Nolvasan or other comprable disinfectant. This should be done to any component that your cham may come in contact with - rocks, wood, branches, etc. You definitely want to do all of this before you get him so you are sure he is going into a safe place.
lele
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Chameleon Help & Resource Info
0.1 Veiled Chameleon - Luna. She's now hanging from her big jungle gym in the sky
1.0 Beardie - Darwin
0.2 felines - Kyndra and Lita
0.1 African Clawed Frog - Skipper
0.3 Mad. Hissers (2 died ;(
0.1 Chilean Rose Hair Tarantula - Rosa Leigh
0.1 Goliath Bird-Eater Tarantula - Natasha