Rickettsia typhi: The etiologic agent of murine typhus (see TYPHUS, ENDEMIC FLEA-BORNE).Typhus, Endemic Flea-Borne: 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.Rickettsia: 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.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.Rickettsia Infections: Infections by the genus RICKETTSIA.Rickettsia felis: A species of gram-negative bacteria transmitted by the flea Ctenocephalides felis, and known to infect CATS, oppossums, and humans.Salmonella typhi: A serotype of SALMONELLA ENTERICA which is the etiologic agent of TYPHOID FEVER.Rickettsia rickettsii: 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.Siphonaptera: An order of parasitic, blood-sucking, wingless INSECTS with the common name of fleas.Typhus, Epidemic Louse-Borne: 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.Rickettsia conorii: A species of gram-negative, aerobic bacteria that is the etiologic agent of BOUTONNEUSE FEVER. It resembles RICKETTSIA RICKETTSII but is antigenically distinct and less virulent for animals and man. (From Bergey's Manual of Systematic Bacteriology, vol 1)Orientia tsutsugamushi: 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.Rickettsiaceae: A family of small, gram-negative organisms, often parasitic in humans and other animals, causing diseases that may be transmitted by invertebrate vectors.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Rocky Mountain Spotted Fever: 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.Scrub Typhus: An acute infectious disease caused by ORIENTIA TSUTSUGAMUSHI. It is limited to eastern and southeastern Asia, India, northern Australia, and the adjacent islands. Characteristics include the formation of a primary cutaneous lesion at the site of the bite of an infected mite, fever lasting about two weeks, and a maculopapular rash.Bartonella: A genus of gram-negative bacteria characteristically appearing in chains of several segmenting organisms. It occurs in man and arthropod vectors and is found only in the Andes region of South America. This genus is the etiologic agent of human bartonellosis. The genus Rochalimaea, once considered a separate genus, has recently been combined with the genus Bartonella as a result of high levels of relatedness in 16S rRNA sequence data and DNA hybridization data.Typhoid Fever: An acute systemic febrile infection caused by SALMONELLA TYPHI, a serotype of SALMONELLA ENTERICA.Boutonneuse Fever: A febrile disease of the Mediterranean area, the Crimea, Africa, and India, caused by infection with RICKETTSIA CONORII.Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Seroepidemiologic Studies: EPIDEMIOLOGIC STUDIES based on the detection through serological testing of characteristic change in the serum level of specific ANTIBODIES. Latent subclinical infections and carrier states can thus be detected in addition to clinically overt cases.Ticks: 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)World War II: Global conflict involving countries of Europe, Africa, Asia, and North America that occurred between 1939 and 1945.Tea Tree Oil: Essential oil extracted from Melaleuca alternifolia (tea tree). It is used as a topical antimicrobial due to the presence of terpineol.Aloe: A plant genus of the family Aloeaceae, order Liliales (or Asphodelaceae, Asparagales in APG system) which is used medicinally. It contains anthraquinone glycosides such as aloin-emodin or aloe-emodin (EMODIN).Skin Cream: A water-soluble medicinal preparation applied to the skin.Flea Infestations: Parasitic attack by members of the order SIPHONAPTERA.Yersinia pestis: The etiologic agent of PLAGUE in man, rats, ground squirrels, and other rodents.Bites and StingsHealth Personnel: Men and women working in the provision of health services, whether as individual practitioners or employees of health institutions and programs, whether or not professionally trained, and whether or not subject to public regulation. (From A Discursive Dictionary of Health Care, 1976)United States Food and Drug Administration: An agency of the PUBLIC HEALTH SERVICE concerned with the overall planning, promoting, and administering of programs pertaining to maintaining standards of quality of foods, drugs, therapeutic devices, etc.Pharmacology: The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.Drug-Related Side Effects and Adverse Reactions: Disorders that result from the intended use of PHARMACEUTICAL PREPARATIONS. Included in this heading are a broad variety of chemically-induced adverse conditions due to toxicity, DRUG INTERACTIONS, and metabolic effects of pharmaceuticals.Pharmacology, Clinical: The branch of pharmacology that deals directly with the effectiveness and safety of drugs in humans.Attitude of Health Personnel: Attitudes of personnel toward their patients, other professionals, toward the medical care system, etc.Adverse Drug Reaction Reporting Systems: Systems developed for collecting reports from government agencies, manufacturers, hospitals, physicians, and other sources on adverse drug reactions.Proteome: The protein complement of an organism coded for by its genome.Physiology: The biological science concerned with the life-supporting properties, functions, and processes of living organisms or their parts.Educational Measurement: The assessing of academic or educational achievement. It includes all aspects of testing and test construction.Anatomy: A branch of biology dealing with the structure of organisms.Pick Disease of the Brain: A rare form of DEMENTIA that is sometimes familial. Clinical features include APHASIA; APRAXIA; CONFUSION; ANOMIA; memory loss; and personality deterioration. This pattern is consistent with the pathologic findings of circumscribed atrophy of the poles of the FRONTAL LOBE and TEMPORAL LOBE. Neuronal loss is maximal in the HIPPOCAMPUS, entorhinal cortex, and AMYGDALA. Some ballooned cortical neurons contain argentophylic (Pick) bodies. (From Brain Pathol 1998 Apr;8(2):339-54; Adams et al., Principles of Neurology, 6th ed, pp1057-9)Computer-Assisted Instruction: A self-learning technique, usually online, involving interaction of the student with programmed instructional materials.Teaching: The educational process of instructing.Curriculum: A course of study offered by an educational institution.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Mitochondria: Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)MoscowNew HampshireBrazilAnaplasma phagocytophilum: A species of gram-negative bacteria in the genus ANAPLASMA, family ANAPLASMATACEAE, formerly called Ehrlichia phagocytophila or Ehrlichia equi. This organism is tick-borne (IXODES) and causes disease in horses and sheep. In humans, it causes human granulocytic EHRLICHIOSIS.Rhipicephalus sanguineus: A species of tick (TICKS) in the family IXODIDAE, distributed throughout the world but abundant in southern Europe. It will feed on a wide variety of MAMMALS, but DOGS are its preferred host. It transmits a large number of diseases including BABESIOSIS; THEILERIASIS; EHRLICHIOSIS; and MEDITERRANEAN SPOTTED FEVER.Bartonella henselae: A species of gram-negative bacteria that is the etiologic agent of bacillary angiomatosis (ANGIOMATOSIS, BACILLARY). This organism can also be a cause of CAT-SCRATCH DISEASE in immunocompetent patients.