A species of gram-negative bacteria that causes rickettsialpox. The vector is a mouse mite and the reservoirs are mites and mice.

A genus of gram-negative, aerobic, rod-shaped bacteria often surrounded by a protein microcapsular layer and slime layer. The natural cycle of its organisms generally involves a vertebrate and an invertebrate host. Species of the genus are the etiological agents of human diseases, such as typhus.

Infections by the genus RICKETTSIA.

Infections with bacteria of the family RICKETTSIACEAE.

A species of gram-negative, aerobic bacteria that is the etiologic agent of ROCKY MOUNTAIN SPOTTED FEVER. Its cells are slightly smaller and more uniform in size than those of RICKETTSIA PROWAZEKII.

A species of gram-negative, aerobic bacteria that is the etiologic agent of epidemic typhus fever acquired through contact with lice (TYPHUS, EPIDEMIC LOUSE-BORNE) as well as Brill's disease.

The etiologic agent of murine typhus (see TYPHUS, ENDEMIC FLEA-BORNE).

An acute febrile illness caused by RICKETTSIA RICKETTSII. It is transmitted to humans by bites of infected ticks and occurs only in North and South America. Characteristics include a sudden onset with headache and chills and fever lasting about two to three weeks. A cutaneous rash commonly appears on the extremities and trunk about the fourth day of illness.

A species of gram-negative bacteria transmitted by the flea Ctenocephalides felis, and known to infect CATS, oppossums, and humans.

The classic form of typhus, caused by RICKETTSIA PROWAZEKII, which is transmitted from man to man by the louse Pediculus humanus corporis. This disease is characterized by the sudden onset of intense headache, malaise, and generalized myalgia followed by the formation of a macular skin eruption and vascular and neurologic disturbances.

A febrile disease of the Mediterranean area, the Crimea, Africa, and India, caused by infection with RICKETTSIA CONORII.

A gram-negative, rod-shaped to coccoid bacterium. It is the etiologic agent of SCRUB TYPHUS in humans and is transmitted by mites from rodent reservoirs.

An infectious disease clinically similar to epidemic louse-borne typhus (TYPHUS, EPIDEMIC LOUSE-BORNE), but caused by RICKETTSIA TYPHI, which is transmitted from rat to man by the rat flea, XENOPSYLLA CHEOPIS.

Blood-sucking acarid parasites of the order Ixodida comprising two families: the softbacked ticks (ARGASIDAE) and hardbacked ticks (IXODIDAE). Ticks are larger than their relatives, the MITES. They penetrate the skin of their host by means of highly specialized, hooked mouth parts and feed on its blood. Ticks attack all groups of terrestrial vertebrates. In humans they are responsible for many TICK-BORNE DISEASES, including the transmission of ROCKY MOUNTAIN SPOTTED FEVER; TULAREMIA; BABESIOSIS; AFRICAN SWINE FEVER; and RELAPSING FEVER. (From Barnes, Invertebrate Zoology, 5th ed, pp543-44)

An order of parasitic, blood-sucking, wingless INSECTS with the common name of fleas.