What is an example of a protozoan disease that is sexually transmitted?

Trichomoniasis is indeed an example of a protozoan disease that is sexually transmitted. The causative agent of trichomoniasis is the protozoan parasite Trichomonas vaginalis. This organism primarily infects the urogenital tract and is spread through sexual contact, making it a sexually transmitted infection (STI).

The characteristics of Trichomonas vaginalis allow it to thrive in the vaginal and urethral environments, leading to symptoms such as itching, discharge, and discomfort during urination, although many individuals may be asymptomatic. Its transmission is closely linked to sexual activity, which classifies it distinctly as a sexually transmitted protozoan disease.

In contrast, giardiasis is caused by Giardia lamblia, a protozoan that is typically transmitted through the fecal-oral route, often via contaminated water. Malaria, while a significant protozoan disease, is transmitted by mosquitoes rather than sexually. Amoebic dysentery is caused by Entamoeba histolytica, which also follows a fecal-oral transmission route and does not involve sexual transmission mechanisms. Thus, trichomoniasis stands out as the only option among these that is directly related to sexual transmission.