Abstract Background Tsetse flies are vectors of African trypanosomes. protozoan parasites that cause sleeping sickness (or human African trypanosomosis) in humans and nagana (or animal African trypanosomosis) in livestock. In addition to trypanosomes. four symbiotic bacteria Wigglesworthia glossinidia. https://allfixelectricales.shop/product-category/fridge-defrost-tray/