Source, Reptile Magazine: Read the full article about common internal parasites in reptiles.
“A parasite is any animal that lives on or within a second animal, and for the most part, parasites live in harmony with their hosts in the wild.
They derive sustenance or protection from them, and although they may not offer any benefit in return, this delicate balance between parasite and host in the wild takes on new meaning in captive reptiles. In some cases, a parasite that would not normally harm its reptile host in the wild can cause deadly disease in captivity.
In the wild, where an animal is not confined within a small space such as a cage, parasites are not found in high numbers, and the parasite burden to a reptile host is usually low.
If the parasite is present in high numbers it may be harmful, and in captivity, especially in dirty cages, the concentration of parasites can be much higher, and hence, more dangerous.”