ASCP Parasitology Practice Exam 2026 – Comprehensive All-in-One Guide to Master Your Certification!

The organism that is not commonly associated with waterborne diseases is Taenia saginata. This organism is a type of tapeworm primarily transmitted through the ingestion of undercooked beef that contains cysticerci (larval stage). While it can cause gastrointestinal symptoms, its transmission route is primarily foodborne rather than waterborne.

In contrast, the other organisms listed are well-known for their association with waterborne diseases. Giardia lamblia is a protozoan that is often found in contaminated water and causes giardiasis. Cryptosporidium species are also protozoan parasites commonly associated with drinking water contamination, leading to cryptosporidiosis. Entamoeba histolytica is another protozoan that can cause amoebic dysentery and is transmitted through water contaminated with feces.

Therefore, Taenia saginata stands out as the correct answer since its primary method of transmission does not involve water.