Human African trypanosomiasis (HAT), also known as sleeping sickness, is caused by single-celled parasites, Trypanosoma bruceiTrypanosoma bruceiT. brucei is a typical unicellular eukaryotic cell, and measures 8 to 50 μm in length. It has an elongated body having a streamlined and tapered shape. Its cell membrane (called pellicle) encloses the cell organelles, including the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, and ribosomes.
› wiki › Trypanosoma_bruceiTrypanosoma brucei - Wikipedia, which are transmitted to humans by infected tsetse flies.