Infection caused by Rickettsia quintana and transmitted by lice. Rickettsiae have characteristics of both viruses and bacteria, and the various forms cause illnesses with fever and skin rashes as their most important manifestations (including Q fever and typhus). They are transmitted by ticks, lice, mites or fleas, which explains the prevalence of the disease at times of war, poverty and undernourishment, and particularly during the two World Wars. Characteristics of the disease are one to two days of high fever, followed by five fever-free days. Skin rashes, mild bleeding, headache and muscular pain can occur. Few patients die of the disease, and it is now rare. Treatment is with antibiotics.