Topic overview

Start with the big picture

The lesson surveys protozoal infections across mosquito-, fly-, tick-, and insect-borne disease, food- and water-associated illness, sexual transmission, and exposure to freshwater, soil, or cats and meat. It connects recognizable presentations—such as cyclic fever and anemia, dysentery, malabsorption, watery diarrhea, ulcers, cardiomyopathy, and meningoencephalitis—with diagnostic methods including blood or stool testing, serology, PCR, microscopy, and antigen tests. Treatment examples are paired with specific organisms, with attention to distinctions such as disease stage, immune status, and partner treatment where noted. The preview introduces these clinical patterns; the full lesson develops the organism-by-organism overview and transmission routes.