Camp fever

Camp fever was one of several historical names for epidemic typhus, a disease caused by the bacterium Rickettsia prowazekii and spread by the human body louse. It brings high fever, severe headache, a rash that spreads from the trunk, and confusion or stupor. Without antibiotics, many of those infected died, older patients most of all.

The older names say where it was found: gaol fever, ship fever, camp fever. Typhus thrives in cold weather, in crowding, and where people cannot wash or change clothes, because those conditions let lice pass from person to person.

Before the nineteenth century, physicians did not reliably tell typhus apart from typhoid or other fevers. A historical record of camp fever cannot always be read as typhus.

In 1909 Charles Nicolle, working in Tunis, showed that the body louse transmits the disease. Several researchers who studied it died of it, including Howard Ricketts and Stanislaus von Prowazek, whose names the bacterium carries.

1. The louse. Body lice live in the seams of clothing and feed on blood. A louse that feeds on an infected person becomes infected.
2. Transmission. The louse passes the bacterium in its droppings. Scratching rubs them into bites and broken skin. Dried droppings in clothing and bedding can also infect.
3. Illness. After about one to two weeks, fever and headache begin, followed by the rash.
4. Control. Breaking the chain meant removing lice: bathing, and heating or chemically treating clothing. In Naples in 1943 and 1944, Allied teams dusted large numbers of civilians with DDT and stopped an outbreak.

• The retreat from Russia, 1812. Typhus is widely held to be one of the diseases that destroyed Napoleon's Grande Armée. In 2006 researchers reported DNA of the typhus bacterium, and of trench fever, in remains from a mass grave of the army's soldiers in Vilnius.
• Bergen-Belsen, 1945. Typhus spread through the overcrowded concentration camp in the months before liberation. Anne Frank and her sister Margot are thought to have died of it there in early 1945.