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ehrlichiosis
ehr·lich·i·o·sis E5057600 (âr-lĭk′ē-ō′sĭs)n. Infection with parasitic rickettsiae of the genus Ehrlichia, especially E. sennetsu, that are transmitted by ticks and produce manifestations in humans similar to those of Rocky Mountain spotted fever, including rash, muscle pain, and fever.
[New Latin Ehrlichia, family name (after Paul Ehrlich) + -osis.]ehr•lich•i•o•sis (ɜrˌlɪk iˈoʊ sɪs)
n. an infection caused by bacteria of the genus Ehrlichia, which are thought to be transmitted to humans and animals by ticks. [after Paul Ehrlich] ehrlichiosis
ehrlichiosis (ârlĭkēō`sĭs), any of several diseases caused by rickettsia of the genera Ehrlichia and Anaplasma. Ehrlichiosis is transmitted by ticks. Both human forms tend to develop about nine days after a tick bite. Symptoms include severe headache and chills and low white blood cell and platelet counts. The lack of a rash distinguishes them from Rocky Mountain spotted feverRocky Mountain spotted fever,
infectious disease caused by a rickettsia. The bacterium is harbored by wild rodents and other animals and is carried by infected ticks of several species that attach themselves to humans.
..... Click the link for more information. and Lyme diseaseLyme disease
or Lyme borreliosis,
a nonfatal bacterial infection that causes symptoms ranging from fever and headache to a painful swelling of the joints. The first American case of Lyme's characteristic rash was documented in 1970 and the disease was first identified
..... Click the link for more information. ; lack of upper respiratory and gastrointestinal symptoms distinguishes them from influenzainfluenza
or flu,
acute, highly contagious disease caused by a RNA virus (family Orthomyxoviridae); formerly known as the grippe. There are three types of the virus, designated A, B, and C, but only types A and B cause more serious contagious infections.
..... Click the link for more information. . Many cases are mild, and all are treatable with antibiotics (tetracycline and doxycycline); however, ehrlichiosis can be fatal in some cases when diagnosis and treatment are delayed. It was known for years that certain Ehrlichia species (some believe them to be variant strains of a single species) can cause disease in animals, for example E. canis and E. ewingii in dogs and E. phagocytophila in sheep and cattle. In the mid-1980s human ehrlichiosis was first recognized. The causative agent was found to be E. chaffeensis. This form is now known as human monocytic ehrlichiosis. In 1990 another form of the disease, human granulocytic ehrlichiosis, was identified. Althought the disease is now known as human granulocytic anaplasmosis (E. phagocytophilum, the causative agent, has been reclassified as Anaplasma phagocytophilum), the term ehrlichiosis continues to be used generically to describe the infection. Other species of Ehrlichia, such as E. ewingii, also cause ehrlichiosis in humans. The organisms invade various white blood cells (see bloodblood,
fluid pumped by the heart that circulates throughout the body via the arteries, veins, and capillaries (see circulatory system; heart). An adult male of average size normally has about 6 quarts (5.6 liters) of blood.
..... Click the link for more information. ; immunityimmunity,
ability of an organism to resist disease by identifying and destroying foreign substances or organisms. Although all animals have some immune capabilities, little is known about nonmammalian immunity.
..... Click the link for more information. ). E. chaffeensis commonly invades monocytes; A. phagocytophilum and E. ewingii invade granulocytes. ehrlichiosis[är‚lik·ē′ō·səs] (medicine) A tick-borne bacterial infection caused by two distinct Ehrlichia species that infect white blood cells; the infection may be asymptomatic, but it also can produce illness ranging from a few mild symptoms to an overwhelming multisystem disease. ehrlichiosis
Ehrlichiosis DefinitionEhrlichiosis is a bacterial infection that is spread by ticks. Symptoms include fever, chills, headache, muscle aches, and tiredness.DescriptionEhrlichiosis is a tick-borne disease caused by infection with Ehrlichia bacteria. Ticks are small, blood-sucking arachnids. Although some ticks carry disease-causing organisms, most do not. When an animal or person is bitten by a tick that carries bacteria, the bacteria are passed to that person or animal during the tick's feeding process. It is believed that the tick must remain attached to the person or animal for at least 24 hours to spread the infection.There are two forms of ehrlichiosis in the United States; human monocytic ehrlichiosis and human granulocytic ehrlichiosis. Monocytic ehrlichiosis is caused by Ehrlichia chaffeensis, which is spread by the Lone Star tick, Amblyomma americanum. As of early 1998, about 400 cases of monocytic ehrlichiosis had been reported in 30 states, primarily in the southeastern and south central United States. The bacteria that causes granulocytic ehrlichiosis is not known, but suspected to be either Ehrlichia equi or Ehrlichia phagocytophila. Granulocytic ehrlichiosis is probably spread by the blacklegged tick Ixodes scapularis (which also spreads Lyme disease). About 100 cases of granulocytic ehrlichiosis have been reported in Connecticut, Massachusetts, Rhode Island, Minnesota, New York, and Wisconsin.Causes and symptomsBoth forms of ehrlichiosis have similar symptoms, and the illnesses can range from mild to severe and life-threatening. Risk factors include old age and exposure to ticks through work or recreation. Symptoms occur seven to 21 days following a tick bite although patients may not recall being bitten. Fever, tiredness, headache, muscle aches, chills, loss of appetite, confusion, nausea, and vomiting are common to both diseases. A rash may occur.DiagnosisEhrlichiosis may be diagnosed and treated by doctors who specialize in blood diseases (hematologists) or an infectious disease specialist. Because ehrlichiosis is not very common and the symptoms are not unique, it may be misdiagnosed. A recent history of a tick bite is helpful in the diagnosis. Blood tests will be done to look for antibodies to Ehrlichia. Staining and microscopic examination of the blood sample may show Ehrlichia bacteria inside white blood cells. Another test, called polymerase chain reaction (PCR), is a very sensitive assay to detect bacteria in the blood sample, but it is not always available.TreatmentAntibiotic treatment should begin immediately if ehrlichiosis is suspected, even if laboratory results are not available. Treatment with either tetracycline (Sumycin, Achromycin V) or doxycycline (Monodox, Vibramycin) is recommended. Many patients with ehrlichiosis are admitted to the hospital for treatment.PrognosisFor otherwise healthy people, a full recovery is expected following treatment for ehrlichiosis. Elderly patients are at a higher risk for severe disease, which may be fatal. Serious complications include lung or gastrointestinal bleeding. Two to 10 patients out of 100 die from the disease.PreventionThe only prevention for ehrlichiosis is to minimize exposure to ticks by staying on the trail when walking through the woods, avoiding tall grasses, wearing long sleeves and tucking pant legs into socks, wearing insect repellent, and checking for ticks after an outing. Remove a tick as soon as possible by grasping the tick with tweezers and gently pulling.Key termsTick-borne disease — A disease that is spread to animals by the bite of an infected tick.ResourcesBooksMcDade, Joseph E., and James G. Olsen. "Ehrlichiosis, Q Fever, Typhus, Rickettsialpox, and Other Rickettsioses." In Infectious Diseases. 2nd ed. Philadelphia: W. B. Saunders Co., 1998.ehr·lich·i·o·sis (er-lik'ē-ō'sis), Infection with leukocytic rickettsiae of the genus Ehrlichia; in humans, especially by E. sennetsu that produces manifestations similar to those of Rocky Mountain spotted fever.ehrlichiosis (âr-lĭk′ē-ō′sĭs)n. Infection with parasitic rickettsiae of the genus Ehrlichia, especially E. sennetsu, that are transmitted by ticks and produce manifestations in humans similar to those of Rocky Mountain spotted fever, including rash, muscle pain, and fever.ehrlichiosis Infectious disease A rare tick-borne infection, caused by Ehrlichia canis, that usually affects dogs Clinical Fever, chills, rigors, malaise, nausea, myalgia, anorexia, encephalopathy, acute respiratory failure with infiltrates, acute renal failure with ↑ creatinine Lab ↓ platelets, ↑ transaminases Treatment Chloramphenicol, tetracyclineehr·lich·i·o·sis (ār-lik'ē-ō'sis) A tick-borne infection of humans, dogs, and many other mammals caused by bacteria from the Neorickettsia, Anaplasma, and Ehrlichia groups; produces manifestations similar to those of Rocky Mountain spotted fever. Ehrlichiosis A rare human infection with Ehrlichia organisms such as E. canis that normally infect animals. The first known human infection was described in Japan in 1954. The illness is usually acquired by a tick bite and resembles glandular fever (infective mononucleosis). A new species, E. chaffeensis , was isolated in 1991 and a third in 1994. The disease is largely confined to the Southeast and mid-Atlantic states of the USA.ehr·lich·i·o·sis (er-lik'ē-ō'sis) Infection with leukocytic rickettsiae of the genus Ehrlichia; in humans, especially by E. sennetsu, which produces manifestations similar to those of Rocky Mountain spotted fever. |