“I found this worm/larva in the toilet bowl on top of one of my bowel movements,” says this reader about the purplish, brown creature in the photo below. He has no idea if the creature came from him or if it was already in the toilet, and he asks if we can identify it for him.

Our reader stresses that he found the worm “alive” and that he “pulled it off the top” of his excretion: “it didn’t seem buried in it at all, just sitting there.” Our reader also asks if we know if it is possible that this creature was inside him. He has had no diarrhea, discomfort or fever lately, and he feels completely fine. Nevertheless, he is still “a bit freaked out that this could have been inside” him, which is completely understandable.

Firstly, we need to point out that we will not be able to confirm if our reader has a parasitic infestation or not. As we are not medical professionals, we are neither qualified nor capable of approaching situations of a medical nature. For that reason, if our reader does at some point think the worm is from him (perhaps he finds more in his excrement or he starts developing symptoms), then we urge him to seek medical advice from an infectious disease physician. What we can recommend is that our reader do one or more of the following:

1) Search for a medical parasitologist in his area using this directory of medical parasitology consultants: https://www.astmh.org/for-astmh-members/clinical-consultants-directory.
2) Search for a local parasitologist by doing a Google search for “medical parasitologist (name of the closest big city)” or “tropical medicine specialist (name of the closest big city)”.
3) Get in touch with Dr. Omar Amin at the Parasitology Center at https://www.parasitetesting.com.

Secondly, despite the possibility that this worm came from our reader, the situation is not necessarily medical in nature. Many of our other readers have found worms in their toilet that are not parasites, so we have to take this possibility into consideration as well. That said, if our reader does suspect or find out that he does have a parasite, then he should disregard any identification made here. So, if this is not a parasite, we would suggest that it is some sort of caterpillar, simply based on its segmentation and the legs we can see in the shadow of the second picture below. To be more specific, this looks like a black cutworm. Cutworms are moth larvae that feed on various plants and which have proven a nuisance to many gardeners and farmers. Their notoriety stems from the swiftness with which they chew through the stems of plants and cut them down (hence, the name). Yet, despite their infamy, cutworms are not parasitic or directly harmful to humans or animals in any way. If this is indeed a cutworm (or a caterpillar of some kind), all our reader needs to do is move the creature outside. Its appearance in our reader’s toilet is likely accidental.

To conclude, we cannot say with certainty what our reader found in his toilet, given his fear that his situation is medical in nature. That being said, we highly think this is a cutworm rather than a parasite, as there are no parasites of this size and shape, and its features are very characteristic of a caterpillar. While we could not provide any concrete answers, we hope this helps our reader to some degree!

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