Werner-His disease: Named for the German physician Heinrich Werner (who did not describe Werner's prematute aging syndrome) and the Swiss physician Wilhelm His, Jr. (who did describe the bundle of His in the heart), this is a louse-borne disease that was first recognized in the trenches of World War I and so was called trench fever. Werner-His disease (trench fever) is estimated to have affected more than a million people in Russia and on the war fronts in Europe. Trench fever was again a major problem in the military in World War II and is seen endemically in Mexico, Africa, E. Europe, and elsewhere. Urban trench fever occurs among the homeless people and people with alcoholism today. Outbreaks have been documented, for example, in Seattle, Baltimore (among injection-drug users), Marseilles (France) and Burundi. The cause of trench fever is Bartonella quintana (also called Rochalimaea quintana), an unusual rickettsial organism that multiplies in the gut of the body louse. Transmission of the rickettsia to people can occur by rubbing infected louse feces into abraded (scuffed) skin or into the conjunctivae (whites of the eyes). The disease is classically a 5-day fever. The onset of symptoms is sudden with high fever, severe headache, back pain and leg pain and a fleeting rash. Recovery takes a month or more. Relapses are common. It is now clear, that at least in its urban form among the homeless, trench fever can be associated with nonspecific symptoms or no symptoms (New England Journal of Medicine 340: 184-189, 1999). The organism (B. quintana) that causes trench fever also has been found responsible for a disease called bacillary angiomatosis in people infected with HIV and for infection of the heart and great vessels (endocarditis) with bloodstream infection. Trench fever is also called Wolhynia fever, shin bone fever, quintan fever, five-day fever, Meuse fever, His disease, and His-Werner disease.