Penicillin injection. Doctor and nurse during World War II carrying out a penicillin injection following a cisternal (suboccipital) puncture at the base of the skull of a patient with meningitis (inflammation of the brain membranes). The puncture is carried out to relieve the pressure building up on the brain, and also to obtain cerebrospinal fluid (CSF) for laboratory analysis. The pencillin injection is intended to prevent secondary infections. Penicillin had been discovered in 1928, but was not widely used as an antibiotic until its mass production for the US Army in World War II. Photographed on 25 January 1945, in an evacuation hospital in Luxembourg.