The First World War spurred medical innovations that have since saved countless lives. In a war of attrition, where huge armies met in battles that could go on for months, keeping the men fit to fight required as much thought and effort as battle preparations.  While the military war was waged in intermittent battles against the enemy across no man’s land, the medical war was an endless fight against mites and microbes and horrific bodily damage wrought by the mass killing machines of the First World War. Victory on both fronts required medical breakthroughs. Men, mites and microbes “Well! I don’t know which is the worst. The war or the lice.… When we are in the trenches, what little time we get to sleep, the lice won’t let us.” —Samuel Warren Ball, April 1917 (from the Canadi...