Men in the trenches suffered from lice. One soldier writing after the war described them as "pale fawn in colour, and they left blotchy red bite marks all over the body." They also created a sour; stale smell. Various methods were used to remove the lice. A lighted candle was fairly effective but the skill of burning the lice without burning your clothes was only learnt with practice. George Coppard described how this worked: "The things lay in the seams of trousers, in the deep furrows of long thick woolly pants, and seemed impregnable in their deep entrenchments. A lighted candle applied where they were thickest made them pop like Chinese crackers. After a session of this, my face would be covered with small blood spots from extra big fellows which had popped too vigorously."
In his autobiography, Harry Patch explains the problems he had with lice on the Western Front: "The lice were the size of grains of rice, each with its own bite, each with its own itch. When we could, we would run hot wax from a candle down the seams of our trousers, our vests - whatever you had - to burn the buggers out. It was the only thing to do. Eventually, when we got to Rouen, coming back, they took every stitch off us and gave us a suit of sterilised blue material. And the uniforms they took off, they burned them - to get rid of the lice."
Where possible the army arranged for the men to have baths in huge vats of hot water while their clothes were being put through delousing machines. Unfortunately, this rarely worked. A fair proportion of the eggs remained in the clothes and within two or three hours of the clothes being put on again a man's body heat had hatched them out.
At the Passchendaele Lieutenant Robert Sherriff described his men going into battle: "At dawn on the morning of the attack, the battalion assembled in the mud outside the huts. I lined up my platoon and went through the necessary inspection. Some of the men looked terribly ill: grey, worn faces in the dawn, unshaved and dirty because there was no clean water. I saw the characteristic shrugging of their shoulders that I knew so well. They hadn't had their clothes off for weeks, and their shirts were full of lice."
Lieutenant John Reith was very successful in dealing with lice. According to his diary: "No lice had so far come my way, but I was always in fear of them. On going into trenches I used to spray about a gallon of lysol over my bunk below the parapet and generally about the hut; now, with the receipt from home of a box of mercurial ointment, I took for the first time to wearing my identity disc, drawing the string through the ointment. I had heard that this was a louse deterrent. It made one's neck dirty but there was never a louse found."
As well as causing frenzied scratching, lice also carried disease. This was known as pyrrexhia or trench fever. The first symptoms were shooting pains in the shins and was followed by a very high fever. Although the disease did not kill, it did stop soldiers from fighting and accounted for about 15% of all cases of sickness in the British Army.