Ehrlichia

Jump to navigation Jump to search

Ehrlichiosis Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Ehrlichiosis from other Diseases

Epidemiology and Demographics

Risk Factors

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Prevention

Case Studies

Case #1

Ehrlichia On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Ehrlichia

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Ehrlichia

CDC on Ehrlichia

Ehrlichia in the news

Blogs on Ehrlichia

Directions to Hospitals Treating Ehrlichiosis

Risk calculators and risk factors for Ehrlichia

Anaplasmataceae
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Alphaproteobacteria
Order: Rickettsiales
Family: Anaplasmataceae

[1]

Genus: Ehrlichia
Species: Ehrlichia canis
Ehrlichia chaffeensis
Ehrlichia ewingii

This page is about microbiologic aspects of the organism(s).  For clinical aspects of the disease, see Ehrlichiosis.

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Ehrlichia is a genus of rickettsiales bacteria. They are transmitted by ticks. Several species can cause infection (Ehrlichiosis) in humans. The genus is named after German microbiologist Paul Ehrlich. These diseases are considered zoonotic as the main reservoir for the pathogen is in animal, usually mammal species.

Ehrlichia are obligately intracellular pathogens and are transported between cells through the host cell filopodia during initial stages of infection, whereas, in the final stages of infection the pathogen ruptures the host cell membrane.[2]

A new species of Ehrlichia has been discovered inside the deer tick Ixodes scapularis. This newly found organism has only been isolated from deer ticks in Wisconsin and Minnesota in the USA. The species is known as Ehrlichia Wisconsin HM543746.

History

The first ehrlichial disease was first recognized in South Africa during the 19th century. Its tick-borne nature was determined in 1900. The organism itself was demonstrated 1925 when it was recognized to be a rickettsia. It was initially named Rickettsia ruminantium, and is currently named Ehrlichia ruminantium. In 1945 a "infection and treatment" method for livestock was developed. This is still the only commercially available "vaccine" against the disease, which is not a true vaccine, but intentional exposure to the disease with monitoring and antibiotic treatment if needed. In 1985 the organism was first propagated reliably in tissue culture.

See also

References

  1. Garrity, George (2005). Bergey's Manual of Systematic Bacteriology. Springer. ISBN 0-387-24145-0.
  2. Thomas S, Popov VL, Walker DH (2010) Exit Mechanisms of the Intracellular Bacterium Ehrlichia. PLoS ONE 5(12): e15775. http://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0015775

External links