Which infection is a result of an infestation caused by protozoans?

Amebiasis is caused by the protozoan parasite Entamoeba histolytica, which infects the intestines and can lead to significant gastrointestinal symptoms, including diarrhea, abdominal pain, and, in severe cases, dysentery. This condition is often associated with contaminated food or water, highlighting the importance of sanitation and hygiene practices to prevent its spread.

In contrast, the other options are caused by different pathogens. Travelers' diarrhea is usually linked to bacterial infections, often from E. coli. Norovirus is a viral infection that spreads rapidly in groups, particularly in contaminated food or close environments. Leptospirosis is caused by bacteria of the Leptospira genus and typically results from exposure to contaminated water. Understanding these distinctions helps in recognizing how various infections arise from different types of microorganisms and stresses the importance of sanitation practices in preventing diseases associated with protozoan infestations.