Several distinct rickettsiae (a parasite carried by ticks, fleas, and lice) cause a disease known as typhus in humans.All cause disease with similarities of fever, headache, and rash.

由几种不同的发疹伤寒（可由壁虱，蚤，虱子等传播）引起的疾被人们称为斑疹伤寒。