This little blighter comes in many different forms but all are highly vulnerable to UV treatment. Despite being quite nasty when this gets into your system, it can be all but sterilised with reasonably low levels of UV treatment. You can easily pick this up in a pool due to it being quite resistant to Chlorine and although you’re more likely to pick it up if you’re young, old and/or have a weakened immune system, you can just as easily become infected while at your healthiest.
Cryptosporidium will set up camp in your intestine if you do get infected. They are a unicellular organism that will give similar symptoms to food poisoning when infecting a host. Depending on how healthy you are you could expect the infection to last anywhere from 4 weeks up to 6 months if you’re already weak from something else. If you read a medical journal like I did then be prepared for a grim picture to be painted.
So when UV and Cryptosporidium interact the DNA is disrupted and stops the organism splitting and reproducing. This means that when the bacteria comes to the end of its natural life, it dies without having split and having 2 replacement bacteria. Because the life of one of these is very limited, even ingesting a live sample of UV treated Cryptosporidium would be completely harmless and go unnoticed by the infected person.
It’s hard to keep such a big subject compact but I’ve tried my best. In summary Cryptosporidium = Bad. Treat your water with UV and you won’t have to think about it anymore, easy.