Crypto is what you are thinking it is. The problem with it is that it is nearly impossible to control or kill off. Bleach won't do it. If you get even one animal in a collection with crypto it can very quickly spread to the whole lot of them and the stories are quite sad. In many ways, it is better to dump all your equipment and start over after a crypto outbreak, it is that hard to completely get rid of.
It presents itself like any other parasite, so an owner may take isolation and quarantine precautions, but even washing your hands between animals ( a good standard practice) may not (and usually doesn't) prevent the spread. That's really what makes crypto so bad, there isn't a big neon warning sign that says "crypto" as far as symptoms and it is so very hard to kill once there. (That's why it got into the water system, the chlorine didn't take care of it. If I'm not mistaken, the water is now physically cell filtered for crypto in many places, but it has been a few years since I've looked at that outbreak, I might be off my rocker.)
Somebody stop me if I am wrong, but I also believe that Bearded Dragons are carriers of crypto. It can live just fine in their system and spread to other species that way.
There are treatments, but you are basically talking about treating everything in your collection if you get an outbreak. As I said before, you are almost always better off dumping all the exposed equipment and starting over. A crypto outbreak is one of the most expensive parasites you will encounter, both in terms of life and monetary costs.
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0.1 Albino Leo Gecko
0.1 Crested Gecko
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