epidemic typhus

typhus /ty·phus/ (ti´fus) a group of closely related, acute, arthropod-borne rickettsial diseases that differ in the intensity of certain signs and symptoms, severity, and fatality rate; all are characterized by headache, chills, fever, stupor, and a macular, maculopapular, petechial, or papulovesicular eruption. Often used alone in English-speaking countries to refer to epidemic typhus, and in several European languages to refer to typhoid fever.ty´phous

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endemic typhus  murine t.

epidemic typhus  the classic form, due to Rickettsia prowazekii and transmitted between humans by body lice.

flying squirrel typhus  an acute infectious disease similar to epidemic typhus, occurring in the southeastern United States; it is caused by Rickettsia prowazekii and is transmitted by the fleas and lice of the flying squirrel.

Kenya tick typhus  boutonneuse fever.

murine typhus  an infectious disease, clinically similar to epidemic typhus but milder, due to Rickettsia typhi, transmitted from rat to human by the rat flea and rat louse.

recrudescent typhus  Brill's disease.

scrub typhus  an acute, typhus-like infectious disease caused by Rickettsia tsutsugamushi and transmitted by chiggers, characterized by a primary skin lesion at the site of inoculation and development of a rash, regional lymphadenopathy, and fever.

tropical typhus  scrub t.

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epidemic typhus

n.

A form of typhus characterized by high fever, mental and physical depression, and macular and papular eruptions; it is caused by Rickettsia prowazekii and transmitted by body lice.

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epidemic typhus,

an acute severe rickettsial infection characterized by prolonged high fever, headache, and a dark maculopapular rash that covers most of the body. The causative organism, Rickettsia prowazekii, is transmitted indirectly as a result of the bite of the human body louse or squirrel flea or louse; the pathogen is contained in feces of the louse and enters the body tissues as the bite is scratched. Disease is manifested by the abrupt onset of an intense headache and a fever reaching 40° C (104° F) beginning after an incubation period of 1 week. The rash follows on the fifth day of onset. Complications may include vascular collapse, renal failure, pneumonia, or gangrene. Mortality rate is as high as 40% depending on preexisting clinical conditions. Treatment may include antipyretics and supportive symptomatic care. Health care workers are at risk of acquiring this infection from louse bites or louse feces. Also called classic typhus, European typhus, jail fever, louse-borne typhus. Compare murine typhus. See also Brill-Zinsser disease, Rickettsia , typhus.

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epidemic

a level of disease occurrence in an animal population which is significantly greater than usual; only occasionally present in the population, widely diffused and rapidly spreading. The disease is clustered in space and time. The word has common usage in veterinary science in preference to the more accurate, epizootic.

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common source epidemic

see point epidemic (below).

epidemic curve

see epidemic curve.

epidemic diarrhea of infant mice

see murine epizootic diarrhea.

epidemic hyperthermia

poisoning by Neotyphodium (Acremonium) coenophialum; called also fescue summer toxicosis.

multiple event epidemic

when the epidemic begins at about the same time in a number of places, e.g. when a poisoned batch of feed is supplied to a number of farms.

point epidemic

when the epidemic begins at one central point, with a large number of animals coming in contact with the source over a short time; a very rapid form of spread with a number of cases presenting with the same stage of the disease at the one time, indicating the single source of the pathogen.

propagated epidemic, propagative epidemic, propagating epidemic

outbreaks in which the disease propagates in one or more initial cases and then spreads to others, a relatively slow method of spread.

epidemic tremor

see avian encephalomyelitis.

epidemic typhus

see rickettsiaprowazeki.

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typhus

acute infectious diseases caused by Rickettsia which are usually transmitted from infected rats and other rodents to humans by lice, fleas, ticks and mites.

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Abyssinian tick typhus

see boutonneuse fever.

canine typhus, canine tick typhus

see canine ehrlichiosis.

epidemic typhus

see rickettsiaprowazeki.

Kenya typhus

see boutonneuse fever.

murine typhus

a disease of humans caused by Rickettsia typhae; rats and cats are the mammalian reservoir.

Queensland tick typhus

caused by Rickettsia australis. See queensland tick typhus.

Sao Paulo typhus

see rocky mountain spotted fever.

scrub typhus

caused by Orientia tsutsugamushi. Wild rodents and occasionally dogs may be hosts.