Borrelia recurrentis A1

Relapsing fever (RF) is a disease caused by several spirochetes of the genus Borrelia. Relapsing fever borrelioses are characterized by recurrent febrile episodes and spirochetemia. There are 2 forms; louse-borne relapsing fever (also known as urban or epidemic RF) is caused by Borrelia recurrentis, and is transmitted by the body louse Pediculus humanus humanus. It currently known in Ethiopia. Endemic tick-borne relapsing fever (TBRF) is a zoonotic disease transmitted worldwide by softbody ticks of the genus Ornithodoros. It is caused by at least 15 distinct Borrelia species throughout the world.Borrelia recurrentis strain A1 was isolated from an adult with RF in Ethiopia. RF causes fewer relapses that TBRF but has a higher spontaneous mortality rate despite antibiotics. Previous work suggested that B.recurrentis was very closely related to B.duttonii; the current sequencing project suggests that in fact B.recurrentis should be considered a strain of B.duttonii that is undergoing considerable gene decay. Decay is probably due at least in part to mutated recA and mutS genes in A1. All 6 plasmids in strain A1 have a counterpart in B.duttonii strain Ly (BORDL). (HAMAP: BORRA)