brucei

Brucei is the species epithet in the scientific name Trypanosoma brucei, a flagellated single-celled parasite of the group known as kinetoplastids. It is primarily associated with African trypanosomiasis, also called sleeping sickness in humans and nagana in animals. The name honors David Bruce, who linked the parasite to disease in the early 1900s.

Trypanosoma brucei comprises three major subspecies: T. b. gambiense, T. b. rhodesiense, and T. b. brucei. Gambiense and rhodesiense infect humans, causing human African trypanosomiasis; brucei brucei mainly infects animals. Geographic distribution distinguishes the subspecies, with gambiense in West and Central Africa and rhodesiense in East Africa.

The parasite alternates between a tsetse fly vector, Glossina spp., and mammalian hosts. In the fly, it develops through procyclic forms in the midgut and metacyclic forms in the salivary glands. In mammals, bloodstream forms display a dense variant surface glycoprotein coat that undergoes antigenic variation to evade immunity.

Clinical features in humans range from fever and lymphadenopathy to progressive neuroinvasion and sleep disturbances as the disease advances. Diagnosis relies on detecting trypomastigotes in blood, lymph node aspirates, or cerebrospinal fluid, complemented by serology and molecular tests. Subspecies and disease stage guide treatment choices.

Treatment depends on the subspecies and disease stage; early stages may be treated with suramin (T. b. rhodesiense) or pentamidine (T. b. gambiense). Late-stage disease requires drugs capable of crossing the blood–brain barrier, such as melarsoprol, eflornithine, or combination therapy with nifurtimox. Prevention focuses on tsetse control and active case finding.

In research, T. brucei serves as a model organism for kinetoplastid biology and antigenic variation, and its genome has been extensively studied, providing insights into host–parasite interactions and parasite biology.