Which stage is used to differentiate Taenia solium from Taenia saginata in clinical specimens?

• A. Egg morphology
• B. Proglottids or scolex
• C. Cysticerci in muscle
• D. Ovum color

Answer: (B)

Distinguishing Taenia solium from Taenia saginata relies on features of the adult worm seen in clinical specimens, not on eggs. The stage you examine is the proglottids or the scolex. Eggs from Taenia species look alike, so they don’t reliably tell the two apart. If you have gravid proglottids, you can count the uterine branches—Taenia solium typically has fewer branches (about 7–13), while Taenia saginata has many more (15–30 or more). The scolex also helps: Taenia solium has an armed rostellum with hooks, whereas Taenia saginata has an unarmed rostellum. These morphological features in the adult worm provide a clear way to differentiate the species. Cysticerci in muscle reflect different life cycles and hosts but aren’t the usual stage used for identifying the species in routine clinical specimens.