Category: R

Ulceration of the frenum of the tongue with membrane formation. It occurs after abrasion by the lower central incisors.  

A white blood cell with radially segmented nucleus, found in some T cells in patients with lymphoproliferative disorders.  

Preventing or slowing the growth of rickettsiae.  

A disease caused by an organism of the family Rickettsiaceae. The most common types are the spotted-fever group (Rocky Mountain spotted fever and rick¬ettsialpox), epidemic typhus, endemic typhus, Brill’s disease, Q fever, scrub typhus, and trench fever.  

The causative agent of Rocky Mountain spotted fever. The animal reservoirs are rodents and dogs and the vectors are ticks of several genera.  

The causative agent of epidemic typhus, spread by the human body louse. Unlike most other Rickettsia, humans are the primary reservoir for R. prowazekii, which was once thought to be a strictly human pathogen. Flying squirrels may be animal reservoirs, and humans acquire infection from their lice or fleas.  

The causative agent of a spotted fever that clinically resembles Rocky Mountain spotted fever. It is found only in Australia and neighboring islands.  

The causative agent of boutonneuse fever found in the Mediterranean, parts of Africa, and India. The animal reservoirs are rodents and dogs and the vectors are ticks of several genera.  

The causative agent of rickettsialpox. The animal reservoir is the house mouse and the vector is a mite.  

The causative agent of African tick bite fever, usually found only in sub-Saharan Africa.