130 KB
The head louse Pediculus capitis infests the head of humans and the eggs laid on the hair are known as nits. The body louse Pediculus humanus infests the clothing of humans, particularly those unable to change their clothing.They do not tolerate variations of temperature of more than a few degrees and quickly leave febrile or dead hosts. This peculiarity makes them extremely effective as vectors; P.humanus transmits Rickettsia prowazekii which causes louse borne or epidemic typhus; the rickettsia Rochalimaea quintana which causes trench fever; and the bacterium Borrelia recurrentis which causes epidemic relapsing fever.