"Killing each separate louse is a tedious buisness when a man has hundreds"

Body Lice
Public DomainBody Lice - Credit: CDC

Lice infestation was the norm in the trenches. It is estimated that up to 97% of officers and men who worked and lived in the trenches were afflicted with lice.  It was decidedly a trench phenomenon.  Men who returned home on leave were not similarly affected, and the end of the war in November 1918 brought an end to the problem of infestation.