They could be sick from something else but get rid of a long standing comorbidity of a pariste infection, you bet they are feeling good. They just think that relief from the varied symptoms from parasite is actually something else cured.

Pretty much this, although it seems freeing the immune system from fighting the worm infection really does help it in fighting the Coronavirus infection: https://www.astralcodexten.com/p/ivermectin-much-more-than-you-wanted (Ctrl+F "The Synthesis").

TL;DR: Studies showing a positive effect from Ivermectin on Covid came mostly from areas with high worm infection incidence, areas with low incidence showed no or smaller positive effect.
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