From Insects to Swiss Mice: Effect of Blastocystis Species in the Intestinal Tract

Blastocystis is a widespread enteric protozoan of zoonotic importance, frequently transmitted via contaminated food and water. This study investigated the histopathological impact of Blastocystis on the intestinal architecture of Swiss mice. Isolates were obtained from the external surfaces and digestive tracts of the American cockroach (Periplaneta americana) and the housefly (Musca domestica). Following oral inoculation, mice were sacrificed at 10 days post-infection for histopathological analysis. Findings revealed significant mucosal disruption, with moderate to severe villi erosion observed in the majority of infected subjects. Pathological hallmarks included villi blunting, apical fragmentation, thinning of the intestinal mucosa, and exposure of the lamina propria. Notably, the severity of intestinal damage was comparable between isolates sourced from both insect vectors. These results characterize Blastocystis as a significant intestinal pathogen in a murine model and underscore the critical role of synanthropic insects as mechanical vectors in its transmission cycle.

Blastocystis, Histopathology, Intestinal villi, Swiss Mice

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