Rickettsia is a genus of nonmotile, Gram-negative, nonspore-forming, highly pleomorphic bacteria that may occur in the forms of cocci, bacilli, or threads. The term "rickettsia" has nothing to do with rickets ; the bacterial genus Rickettsia was named after Howard Taylor Ricketts, in honor of his pioneering work on tick-borne spotted fever.
Rocky Mountain spotted fever (RMSF) is a bacterial disease spread by ticks. It typically begins with a fever and headache, which is followed a few days later with the development of a rash. The rash is generally made up of small spots of bleeding and starts on the wrists and ankles. Other symptoms may include muscle pains and vomiting. Long-term complications following recovery may include hearing loss or loss of part of an arm or leg.
Boutonneuse fever is a fever as a result of a rickettsial infection caused by the bacterium Rickettsia conorii and transmitted by the dog tick Rhipicephalus sanguineus. Boutonneuse fever can be seen in many places around the world, although it is endemic in countries surrounding the Mediterranean Sea. This disease was first described in Tunisia in 1910 by Conor and Bruch and was named boutonneuse due to its papular skin-rash characteristics.
Rickettsia rickettsii is a Gram-negative, intracellular, coccobacillus bacterium that is around 0.8 to 2.0 μm long. R. rickettsii is the causative agent of Rocky Mountain spotted fever. R. rickettsii is one of the most pathogenic Rickettsia strains. It affects a large majority of the Western Hemisphere and small portions of the Eastern Hemisphere.
Tick-borne diseases, which afflict humans and other animals, are caused by infectious agents transmitted by tick bites. They are caused by infection with a variety of pathogens, including rickettsia and other types of bacteria, viruses, and protozoa. Because individual ticks can harbor more than one disease-causing agent, patients can be infected with more than one pathogen at the same time, compounding the difficulty in diagnosis and treatment. 16 tick-borne diseases of humans are known, of which four have been discovered since 2013.
Meningoencephalitis, also known as herpes meningoencephalitis, is a medical condition that simultaneously resembles both meningitis, which is an infection or inflammation of the meninges, and encephalitis, which is an infection or inflammation of the brain.
Howard Taylor Ricketts was an American pathologist after whom the family Rickettsiaceae and the order Rickettsiales are named.
A spotted fever is a type of tick-borne disease which presents on the skin. They are all caused by bacteria of the genus Rickettsia. Typhus is a group of similar diseases also caused by Rickettsia bacteria, but spotted fevers and typhus are different clinical entities.Transmission process: When the tick latches on, it needs to be removed under 2 hours. If not noticed or unremoved it takes only 10 hours for the tick to transmit the (disease) to the human
A rickettsiosis is a disease caused by intracellular bacteria.
Rhipicephalus sanguineus, commonly called the brown dog tick, kennel tick, or pantropical dog tick, is a species of tick found worldwide, but more commonly in warmer climates. This species is unusual among ticks in that its entire lifecycle can be completed indoors. The brown dog tick is easily recognized by its reddish-brown color, elongated body shape, and hexagonal basis capituli. Adults are 2.28 to 3.18 mm in length and 1.11 to 1.68 mm in width. They do not have ornamentation on their backs.
African tick bite fever (ATBF) is a bacterial infection spread by the bite of a tick. Symptoms may include fever, headache, muscle pain, and a rash. At the site of the bite there is typically a red skin sore with a dark center. The onset of symptoms usually occurs 4–10 days after the bite. Complications are rare, but may include joint inflammation. Some people do not develop symptoms.
American tick bite fever is a spotted fever disease caused by the tick-borne bacterium Rickettsia parkeri. Symptoms may include a fever, red spots on the skin throughout the body, and an eschar at the site of the tick-bite.
Rickettsia parkeri is a Gram-negative intracellular bacterium. R. parkeri causes mild spotted fever disease in humans,, characterized by headache, rash, fever, and an eschar at the site of tick attachment. It is transmitted via tick bite and found mainly in the Western Hemisphere. Doxycycline and chloramphenicol are the most common drugs of choice for reducing the symptoms associated with disease caused by R. parkeri.
Rickettsia helvetica, previously known as the Swiss agent, is a bacterium found in Dermacentor reticulatus and other ticks, which has been implicated as a suspected but unconfirmed human pathogen. First recognized in 1979 in Ixodes ricinus ticks in Switzerland as a new member of the spotted fever group of Rickettsia, the R. helvetica bacterium was eventually isolated in 1993. Although R. helvetica was initially thought to be harmless in humans and many animal species, some individual case reports suggest that it may be capable of causing a nonspecific fever in humans. In 1997, a man living in eastern France seroconverted to Rickettsia 4 weeks after onset of an unexplained febrile illness. In 2010, a case report indicated that tick-borne R. helvetica can also cause meningitis in humans.
Rickettsia felis is a species of bacterium, the pathogen that causes cat-flea typhus in humans. In cats the disease is known as flea-borne spotted fever. Rickettsia felis also is regarded as the causative organism of many cases of illnesses generally classed as fevers of unknown origin in humans in Africa.
Rickettsia japonica is a species of Rickettsia. It can cause Japanese spotted fever.
Rickettsia peacockii is a species of gram negative Alphaproteobacteria of the spotted fever group, identified from Rocky Mountain wood ticks. Its type strain is SkalkahoT. The organism is passed transstadially and transovarially, and infections are localized in ovarial tissues.
Rickettsia heilongjiangensis is a species of gram negative Alphaproteobacteria, within the spotted fever group, being carried by ticks. It is pathogenic.
Rickettsia raoultii is a tick-borne pathogenic spotted fever group Rickettsia species borne by Dermacentor ticks.
Spotted fever rickettsiosis, also known as spotted fever group rickettsia (SFGR), is a group of infections that include Rocky Mountain spotted fever, Rickettsia parkeri rickettsiosis, Pacific Coast tick fever, and rickettsialpox. The group of infections was created in 2010 as they are difficult to tell apart.
