C. hominis causes the disease, Cryptosporidiosis. The symptoms are: diarrhea, vomiting, anorexia, fever, and abdominal cramping. The respiratory system can be affected as well. It is usually self-limiting, but can be harmful to immunocompromised individuals.
Cryptosporidium parvum causes cryptosporidiosis, a parasitic infection. The symptoms of cryptosporidiosis are: watery diarrhea, stomach cramps, dehydration, nausea, vomiting, fever, and weight loss. In healthy people, the disease created by the parasite is self-limiting, but in immunosuppressed individuals, the disease may be chronic and severe.
Cyanobacteria can produce toxins called cyanotoxins, this comes from the blooms that form. Health effects associated with exposure to cyanobacteria are: stomach and intestinal illness, breathing problems, allergic reactions, skin irritation, liver damage, and neurotoxic reactions.