Query: NC_011244:94756 Borrelia recurrentis A1, complete genome
Lineage: Borrelia recurrentis; Borrelia; Spirochaetaceae; Spirochaetales; Spirochaetes; Bacteria
General Information: Borrelia recurrentis isolated from adult patient with louse-borne relapsing fever in Ethiopia. Borrelia recurrentis is the causative agent of louse-borne relapsing fever. Prior to World War II, this organism was responsible for large disease outbreaks with a mortality of up to 40% in much of the world. Currently this disease is limited to parts of Africa, China, and Peru. B. recurrentis is transmitted when infected human body lice (Pediculus humanus) are crushed and their fluids contaminate mucous membranes or breaks in the skin. Relapsing fever is characterized by a period of chills, fever, headache, and malaise, an asymptomatic period, followed by another episode of symptoms. This cycle of relapsing is due to changes in the surface proteins of Borrelia, which allow it to avoid detection and removal by the host immune system. This antigenic variation is the result of homologous recombination of silent proteins into an expressed locus, causing partial or complete replacement of one serotype with another.
Subject: NC_008710:108057 Borrelia turicatae 91E135, complete genome
Lineage: Borrelia turicatae; Borrelia; Spirochaetaceae; Spirochaetales; Spirochaetes; Bacteria
General Information: This strain was isolated in the USA from the soft tick Ornithodoros turicatae. Borrelia turicatae is the causative agent of tick-borne relapsing fever in the southwestern USA. Ticks become infected with Borrelia while feeding on an infected mammal, usually a rodent or squirrel. Borrelia then multiplies rapidly, causing a generalized infection throughout the tick. While feeding, the tick passes the spirochete into a mammalian host through its infectious saliva. Relapsing fever is characterized by period of chills, fever, headache, and malaise, followed by an asymptomatic, followed by another episode of symptoms. The cycle of relapsing is due to changes in the surface proteins of Borrelia, which allow it to avoid detection and removal by the host immune system. This antigenic variation is the result of homologous recombination of silent proteins into an expressed locus, causing partial or complete replacement of one serotype with another. These plasmids carry genes involved in antigenic variation and pathogenicity.