II. Organisms
- Treponema
- Treponema pallidum (Syphilis)
- Treponema pertenue (Yaws)
- Treponema carateum (pinta)
- Borrelia
- Borrelia recurrentis (Louse-borne Relapsing Fever)
- Borrelia hermsii, Borrelia miyamotoi, Borrelia tunicate (Tick-Borne Relapsing Fever in North America)
- Borrelia Burgdorferi (Lyme Disease)
- Leptospira