Epidemiology
Trench fever is a vector borne disease in which humans are primarily the main hosts. The vector through which the disease is typically transmitted is referred to as the human body louse "Pediculus humanus humanus", which is better known as lice. The British Expeditionary Force Pyrexia of Unknown Origin Enquiry Sub-Committee concluded that the specific means by which the vector infected the host was louse waste entering the body through abraded skin. Although the disease is typically found in humans, the gram negative bacterium which induce the disease have been seen in mammals such as dogs, cats, and macaques in small numbers.Being that the vector of the disease is human body louse, it can be determined that the main risk factors for infection are mostly in relation to contracting body louse. Specifically, some risk factors include: body louse infestation, overcrowded and unhygienic conditions, body hygiene, war, famine, malnutrition, alcoholism, homelessness, and intravenous drug abuse.The identified risk factors directly correlate with the subpopulations of identified infected persons throughout the duration of the known disease. Historically, trench fever was found in young male soldiers of World War I, whereas in the 21st century the disease mostly has a prevalence in middle aged homeless men. This can be seen when looking at a 21st-century outbreak of the disease in Denver, Colorado, where researcher David McCormick and his colleagues came across the gram negative bacterium in 15% of the 241 homeless persons who were tested.
Trench fever (also known as "five-day fever", "quintan fever" (Latin: febris quintana), and "urban trench fever") is a moderately serious disease transmitted by body lice. It infected armies in Flanders, France, Poland, Galicia, Italy, Salonika, Macedonia, Mesopotamia, Russia and Egypt in World War I. Three noted cases during WWI were the authors J. R. R. Tolkien, A. A. Milne, and C. S. Lewis. From 1915 to 1918 between one-fifth and one-third of all British troops reported ill had trench fever while about one-fifth of ill German and Austrian troops had the disease. The disease persists among the homeless. Outbreaks have been documented, for example, in Seattle and Baltimore in the United States among injection drug users and in Marseille, France, and Burundi.Trench fever is also called Wolhynia fever, shin bone fever, Meuse fever, His disease and His–Werner disease or Werner-His disease (after Wilhelm His Jr. and Heinrich Werner). The disease is caused by the bacterium Bartonella quintana (older names: Rochalimea quintana, Rickettsia quintana), found in the stomach walls of the body louse. Bartonella quintana is closely related to Bartonella henselae, the agent of cat scratch fever and bacillary angiomatosis. Signs and symptoms
The disease is classically a five-day fever of the relapsing type, rarely exhibiting a continuous course. The incubation period is relatively long, at about two weeks. The onset of symptoms is usually sudden, with high fever, severe headache, pain on moving the eyeballs, soreness of the muscles of the legs and back, and frequently hyperaesthesia of the shins.