(which itches) and rubs the feces into the wound. The incubation period is one to two weeks. R. prowazekii can remain viable and virulent in the dried louse feces for many days. Typhus will eventually kill the louse, though the disease will remain viable for many weeks in the dead louse. Epidemic typhus has historically occurred during times of war and deprivation. For example, typhus killed millions of prisoners in German Nazi concentration camps during World War II. The unhygenic conditions in camps such as Auschwitz, Theresienstadt, and Bergen-Belsen allowed diseases such as typhus to flourish. Situations in the twenty-first century with potential for a typhus epidemic would include refugee camps during a major famine or natural disaster. In the periods between outbreaks, when human to human transmission occurs less often, the flying squirrel serves as a zoonotic reservoir for the Rickettsia prowazekii bacterium. In 1916, Henrique da Rocha Lima proved that the bacterium Rickettsia prowazekii was the agent responsible for typhus; he named it after H. T. Ricketts and Stanislaus von Prowazek, two zoologists who had died from typhus while investigating epidemics. Once these crucial facts were recognized, Rudolf Weigl in 1930 was able to fashion a practical and effective vaccine production method. He ground up the insides of infected lice that had been drinking blood. It was, however, very dangerous to produce, and carried a high likelihood of infection to those who were working on it. A safer mass-production-ready method using egg yolks was developed by Herald R. Cox in 1938. This vaccine was widely available and used extensively by 1943. Diagnosis IFA, ELISA or PCR positive after 10 days. Treatment The infection is treated with antibiotics. Intravenous fluids and oxygen may be needed to stabilize the patient. There is a significant disparity between the untreated mortality and treated mortality rates: 10-60% untreated versus close to 0% treated with antibiotics within 8 days of initial infection. Tetracycline, chloramphenicol, and doxycycline are commonly used. Infection can also be prevented by vaccination. Some of the simplest methods of prevention and treatment focus on preventing infestation of body lice. Completely changing the clothing, washing the infested clothing in hot water, and in some cases also treating recently used bedsheets all help to prevent typhus by removing potentially infected lice. Clothes left unworn and unwashed for 7 days also result in the death of both lice and their eggs, as they have