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Rickettsioses
A rickettsiosis is a disease caused by intracellular bacteria. Cause Rickettsioses can be divided into a spotted fever group (SPG) and typhus group (TG). In the past, rickettsioses were considered to be caused by species of Rickettsia. However, scrub typhus is still considered a rickettsiosis, even though the causative organism has been reclassified from ''Rickettsia tsutsugamushi'' to ''Orientia tsutsugamushi''.Examples of rickettsioses include typhus, both endemic and epidemic, Rocky Mountain spotted fever, and Rickettsialpox. Organisms involved include Rickettsia parkeri. Many new causative organisms have been identified in the last few decades. Most are in the genus ''Rickettsia'', but scrub typhus is in the genus ''Orientia''. Diagnosis No rapid laboratory tests are available to diagnose rickettsial diseases early in the course of illness, and serologic assays usually take 10–12 days to become positive. Research is indicating that swabs of eschars may be used for molecular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocky Mountain 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. The disease is caused by ''Rickettsia rickettsii'', a type of bacterium that is primarily spread to humans by American dog ticks, Rocky Mountain wood ticks, and brown dog ticks. Rarely the disease is spread by blood transfusions. Diagnosis in the early stages is difficult. A number of laboratory tests can confirm the diagnosis but treatment should be begun based on symptoms. It is within a group known as spotted fever rickettsiosis, together with ''Rickettsia parkeri'' rickettsiosis, Pacific Coast tick fever, and rickettsialpox. Treatment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orientia Tsutsugamushi
''Orientia tsutsugamushi'' (from Japanese ''tsutsuga'' meaning "illness", and ''mushi'' meaning "insect") is a mite-borne bacterium belonging to the family Rickettsiaceae and is responsible for a disease called scrub typhus in humans. It is a natural and an obligate intracellular parasite of mites belonging to the family Trombiculidae. With a genome of only 2.0–2.7 Mb, it has the most repeated DNA sequences among bacterial genomes sequenced so far. The disease, scrub typhus, occurs when infected mite larvae accidentally bite humans. Primarily indicated by undifferentiated febrile illnesses, the infection can be complicated and often fatal. ''Orientia tsutsugamushi'' infection was first reported in Japan by Hakuju Hashimoto in 1810, and to the Western world by Theobald Adrian Palm in 1878. Naosuke Hayashi first described it in 1920, giving the name ''Theileria tsutsugamushi''. Owing to its unique properties, it was renamed ''Orientia tsutsugamushi'' in 1995. Unlike other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spotted Fever
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. The phrase apparently originated in Spain in the 17th century and was ‘loosely applied in England to typhus or any fever involving petechial eruptions.’ During the 17th and 18th centuries, it was thought to be "cousin-germane" to and herald of the bubonic plague, a disease which periodically afflicted the city of London and its environs during the 16th and 17th centuries, most notably during the Great Plague of 1665.Daniel Defoe, ''A Journal of the Plague Year'', ed. Louis Landa (Oxford, 2010) 219. Types of spotted fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typhus
Typhus, also known as typhus fever, is a group of infectious diseases that include epidemic typhus, scrub typhus, and murine typhus. Common symptoms include fever, headache, and a rash. Typically these begin one to two weeks after exposure. The diseases are caused by specific types of bacterial infection. Epidemic typhus is due to ''Rickettsia prowazekii'' spread by body lice, scrub typhus is due to ''Orientia tsutsugamushi'' spread by chiggers, and murine typhus is due to ''Rickettsia typhi'' spread by fleas. Vaccines have been developed, but none are commercially available. Prevention is achieved by reducing exposure to the organisms that spread the disease. Treatment is with the antibiotic doxycycline. Epidemic typhus generally occurs in outbreaks when poor sanitary conditions and crowding are present. While once common, it is now rare. Scrub typhus occurs in Southeast Asia, Japan, and northern Australia. Murine typhus occurs in tropical and subtropical areas of the worl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rickettsialpox
Rickettsialpox is a mite-borne infectious illness caused by bacteria of the genus ''Rickettsia'' (''Rickettsia akari''). Physician Robert Huebner and self-trained entomologist Charles Pomerantz played major roles in identifying the cause of the disease after an outbreak in 1946 in a New York City apartment complex, documented in "The Alerting of Mr. Pomerantz," an article by medical writer Berton Roueché. Although it is not transmitted by a tick (a characteristic of spotted fever), the bacterium is a part of the spotted fever group of ''Rickettsia'', and so this condition is often classified with that group. Signs and symptoms The first symptom is a bump formed by the bite, eventually resulting in a black, crusty scab. Many of the symptoms are flu-like including fever, chills, weakness and achy muscles but the most distinctive symptom is the rash that breaks out, spanning the infected person's entire body. Transmission The bacteria are originally found in mice and cause mites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infectious Disease (medical Specialty)
Infectious diseases or ID, also known as infectiology, is a medical specialty dealing with the diagnosis and treatment of infections. An infectious diseases specialist's practice consists of managing nosocomial ( healthcare-acquired) infections or community-acquired infections and is historically associated with hygiene, epidemiology, clinical microbiology, travel medicine and tropical medicine. Scope Infectious diseases specialists typically serve as consultants to other physicians in cases of complex infections, and often manage patients with HIV/AIDS and other forms of immunodeficiency. Although many common infections are treated by physicians without formal expertise in infectious diseases, specialists may be consulted for cases where an infection is difficult to diagnose or manage. They may also be asked to help determine the cause of a fever of unknown origin. Specialists in infectious diseases can practice both in hospitals (inpatient) and clinics (outpatient). In hospital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rickettsia
''Rickettsia'' is a genus of nonmotile, gram-negative, nonspore-forming, highly pleomorphic bacteria that may occur in the forms of cocci (0.1 μm in diameter), bacilli (1–4 μm long), or threads (up to about 10 μm long). The term "rickettsia" has nothing to do with rickets (which is a deficiency disease resulting from lack of vitamin D); the bacterial genus ''Rickettsia'' instead was named after Howard Taylor Ricketts, in honor of his pioneering work on tick-borne spotted fever. Properly, ''Rickettsia'' is the name of a single genus, but the informal term "rickettsia", plural "rickettsias", usually not capitalised, commonly applies to any members of the order Rickettsiales. Being obligate intracellular bacteria, rickettsias depend on entry, growth, and replication within the cytoplasm of living eukaryotic host cells (typically endothelial cells). Accordingly, ''Rickettsia'' species cannot grow in artificial nutrient culture; they must be grown either in tissue or embryo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrub Typhus
Scrub typhus or bush typhus is a form of typhus caused by the intracellular parasite ''Orientia tsutsugamushi'', a Gram-negative α-proteobacterium of family Rickettsiaceae first isolated and identified in 1930 in Japan.Pediatric Scrub Typhus accessdate: 16 October 2011 Although the disease is similar in presentation to other forms of , its is no longer included in '' |
Rickettsia Parkeri
''Rickettsia parkeri'' (abbreviated ''R. parkeri'') is a gram-negative intracellular bacterium. The organism is found in the Western Hemisphere and is transmitted via the bite of hard ticks of the genus ''Amblyomma''. ''R. parkeri'' causes mild spotted fever disease in humans, whose most common signs and symptoms are fever, an eschar at the site of tick attachment, rash, headache, and muscle aches. Doxycycline is the most common drug used to reduce the symptoms associated with disease. Biology ''R. parkeri'' is classified in the spotted fever group of the genus ''Rickettsia''. Genetically, its close relatives include '' R. africae'', '' R. sibirica'', '' R. conorii'', '' R. rickettsii'', '' R. peacockii'', and '' R. honei''. The organism has been isolated from numerous species of ticks in the genus ''Amblyomma'': '' A. americanum'' in the United States; ''A. aureolatum'' in Brazil; '' A. maculatum'' in Mexico, Peru, and the United States; '' A. nodosum'' in Brazil; ''A. oval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orientia
''Orientia'' is a genus of bacteria in family Rickettsiaceae. They are obligate intracellular, gram-negative bacteria found in insects and mammals. They are spread through the bites or feces of infected insects. The genus comprises the species '' Orientia tsutsugamushi'' and ''Orientia chuto'', which both cause scrub typhus in humans. Candidatus Orientia chiloensis Orientia chiloensis is a possible new species of Orientia identified as such by its highly divergent type-specific antigen gene (tsa). In Chile scrub typhus is known to occur in the southern half of the country and in particular Chiloé Island Chiloé Island ( es, Isla de Chiloé, , ) also known as Greater Island of Chiloé (''Isla Grande de Chiloé''), is the largest island of the Chiloé Archipelago off the west coast of Chile, in the Pacific Ocean. The island is located in southern ... and the fjords and channels of Patagonia. Between 2015 and 2020 there was a total of 40 known cases in Chile with much ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serology
Serology is the scientific study of Serum (blood), serum and other body fluids. In practice, the term usually refers to the medical diagnosis, diagnostic identification of Antibody, antibodies in the serum. Such antibodies are typically formed in response to an infection (against a given microorganism), against other foreign proteins (in response, for example, to a Acute hemolytic transfusion reaction, mismatched blood transfusion), or to one's own proteins (in instances of autoimmune disease). In either case, the procedure is simple. Serological tests Serological tests are diagnostic methods that are used to identify antibodies and antigens in a patient's sample. Serological tests may be performed to diagnose infections and autoimmune illnesses, to check if a person has immunity (medical), immunity to certain diseases, and in many other situations, such as determining an individual's blood type. Serological tests may also be used in forensic serology to investigate crime scene evid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eschar
An eschar (; Greek: ''ἐσχάρᾱ'', ''eskhara''; Latin: ''eschara'') is a slough or piece of dead tissue that is cast off from the surface of the skin, particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections, necrotizing spider bite wounds, tick bites associated with spotted fevers and exposure to cutaneous anthrax. The term ‘eschar’ is not interchangeable with ‘scab’. An eschar contains necrotic tissue whereas a scab is composed of dried blood and exudate. Black eschars are most frequently attributed in medicine to cutaneous anthrax (infection by '' Bacillus anthracis''), which may be contracted through herd animal exposure and also from ''Pasteurella multocida'' exposure in cats and rabbits. A newly identified human rickettsial infection, ''R. parkeri'' rickettsiosis, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation. Eschar is sometimes called a ''black wound'' becau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
