Epidemic typhus (also called camp fever, jail fever, hospital fever, ship fever, famine fever, putrid fever, petechial fever, Epidemic louse-borne typhus, and louse-borne typhus) is a form of typhus so named because the disease often causes epidemics following wars and natural disasters.pidemic typhus (also called camp fever, jail fever, hospital fever, ship fever, famine fever, putrid fever, petechial fever, Epidemic louse-borne typhus, and louse-borne typhus) is a form of typhus so named because the disease often causes epidemics following wars and natural disasters.