They gave live Rickettsia prowazekii to concentration camp prisoners, using them as a control group for the vaccine tests.The use of DDT as an effective means of killing lice, the main carrier of typhus, was discovered in Naples. Society and culture
Biological weapon
Typhus was one of more than a dozen agents that the United States researched as potential biological weapons before President Richard Nixon suspended all non-defensive aspects of the U.S. biological weapons program in 1969. Poverty and displacement
The CDC lists the following areas as active foci of human epidemic typhus: Andean regions of South America, some parts of Africa; on the other hand, the CDC only recognizes an active enzootic cycle in the United States involving flying squirrels (CDC). Though epidemic typhus is commonly thought to be restricted to areas of the developing world, serological examination of homeless persons in Houston found evidence for exposure to the bacterial pathogens that cause epidemic typhus and murine typhus. A study involving 930 homeless people in Marseille, France, found high rates of seroprevalence to R. prowazekii and a high prevalence of louse-borne infections in the homeless.Typhus has been increasingly discovered in homeless populations in developed nations. Typhus among homeless populations is especially prevalent as these populations tend to migrate across states and countries, spreading the risk of infection with their movement.
In 1546, Girolamo Fracastoro, a Florentine physician, described typhus in his famous treatise on viruses and contagion, De Contagione et Contagiosis Morbis.Typhus was carried to mainland Europe by soldiers who had been fighting on Cyprus. The first reliable description of the disease appears during the siege of the Emirate of Granada by the Catholic Monarchs in 1489 during the Granada War. These accounts include descriptions of fever and red spots over arms, back and chest, progressing to delirium, gangrenous sores, and the stench of rotting flesh. During the siege, the Catholics lost 3,000 men to enemy action, but an additional 17,000 died of typhus.Typhus was also common in prisons (and in crowded conditions where lice spread easily), where it was known as Gaol fever or Jail fever. Gaol fever often occurs when prisoners are frequently huddled together in dark, filthy rooms. Imprisonment until the next term of court was often equivalent to a death sentence. Typhus was so infectious that prisoners brought before the court sometimes infected the court itself. Following the Black Assize of Oxford 1577, over 300 died from epidemic typhus, including Speaker Robert Bell, Lord Chief Baron of the Exchequer. The outbreak that followed, between 1577 and 1579, killed about 10% of the English population.During the Lent assize held at Taunton (1730), typhus caused the death of the Lord Chief Baron of the Exchequer, the High Sheriff of Somerset, the sergeant, and hundreds of other persons.