ehrlichiosis


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Related to ehrlichiosis: Human granulocytic 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.
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 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
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; 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.
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. 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.
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; 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.
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). 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.
References in periodicals archive ?
Human monocytic ehrlichiosis (HME) is one of the most common, potentially life-threatening tickborne illnesses in the United States.
Other tick-borne obligate intracellular bacteria pathogenic to humans are E chaffeensis and E ewingii, members of the order Rickettsiales, and agents of human monocytotropic ehrlichiosis (HME) and ewingii ehrlichiosis, respectively.
Dogs affected with canine ehrlichiosis exhibit wide range of clinical manifestations which vary between and within different geographical locations owing to strain variations, breed of dog, immunological status of host and concurrent infections with other tick borne parasites (Rikihisa, 1991).
However, determining the stage of infection in dogs naturally infected with canine ehrlichiosis is difficult because of the possible presence of similar acute and chronic infection clinical signs (HARRUS & WANER, 2011).
canis y de otras posibles especies de la familia Anaplasmateceae en la comunidad de Jobalito, municipio Ribas del estado Aragua, debido al reporte de casos de ehrlichiosis humana en esta zona.
prior to May 1, 2012 Rocky Mountain 0 0 spotted fever (b) Ehrlichiosis, human 0 0 Other tick-borne 0 0 infection, human (a) Note: Table includes only confirmed or probable cases that have been reviewed and closed by Division of Infectious Disease Epidemiology staff (b) Includes all spotted fever rickettsioses
Serological and Molecular Diagnosis of Human Ehrlichiosis in Patients with Clinical Manifestations Associated with the Disease in Zulia, Venezuela, 2004-2005
Being from Long Island, the differential diagnosis included babesiosis and ehrlichiosis as well as bacterial sepsis.
These microorgaisms include those known to cause Lyme Disease, Rocky Mountain Spotted Fever, Babesiosis, Ehrlichiosis and Anaplasmosis.
1) They also may play a role in the spread of human diseases, according to a study of ehrlichiosis and its relationship to the noxious weed Amur honeysuckle (Lonicera maackii).
Post-release from the hospital, results came back seropositive (private laboratory, Tampa) for Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME).