Canine ehrlichiosis
Dr Parvinder Kaur Lubana,
VO, RDDL, Jalandhar, Punjab
Ehrlichiosis is a tick-borne infectious disease of dogs, usually carried by the brown dog tick. The disease seems to be particularly severe in German Shepherd Dogs and Doberman Pinschers.
The organism responsible for this disease is a rickettsial organism. Rickettsiae are similar to bacteria. Ehrlichia canis is the most common rickettsial species involved in ehrlichiosis in dogs, but occasionally other strains of the organism will be found. Because of its origin in military dogs in Vietnam, it has also been called tracker dog disease and tropical canine pancytopenia.
Ehrlichiosis is a disease that develops in dogs after being bitten by an infected tick.”
What are the signs of ehrlichiosis?:
Signs of ehrlichiosis can be divided into three stages:
1) acute (early disease),
2) sub-clinical (no outward signs of disease),
3) clinical or chronic (long-standing infection).
In areas where ehrlichiosis is common, many dogs are seen during the acute phase. In this stage, infected dogs may have fever, swollen lymph nodes, respiratory distress, weight loss, bleeding disorders (spontaneous hemorrhage or bleeding), and occasionally, neurological disturbances (they may seem unsteady or develop meningitis). This stage may last two to four weeks and some dogs may eliminate the infection or head in to the sub-clinical phase.
The sub-clinical phase represents the stage of infection in which the organism is present, but not causing any outward signs of disease. Sometimes a dog will pass through the acute phase without its owner being aware of the infection. These dogs may become sub-clinical and develop changes observed at the laboratory level, yet have no apparent signs of illness. The sub-clinical phase is often considered the worst phase because there are no clinical signs and therefore the disease goes undetected. The only hint that a dog may be infected during this phase may be after a blood sample is drawn, when the dog shows prolonged bleeding from the puncture site. Dogs that are infected sub-clinically may eliminate the organisms or may progress to the next stage,
clinical ehrlichiosis.:
Clinical ehrlichiosis occurs because the immune system is not able to eliminate the organism. Dogs are likely to develop a host of problems: anemia, bleeding episodes, lameness, eye problems (including hemorrhage into the eyes or blindness), neurological problems, and swollen limbs. If the bone marrow (site of blood cell production) fails, the dog becomes unable to manufacture any of the blood cells necessary to sustain life (red blood cells, white blood cells, and platelets).
In blood smear under microscope
Monocytic Ehrlichiosis
Granulocytic Ehrlichiosis
A low platelet count (called thrombocytopenia), anemia (low red blood cell counts), and/or high levels of the protein globulin in the blood may be found.
Treatment :
Dogs experiencing severe anemia or bleeding problems may require a blood transfusion. However, this does nothing to treat the underlying disease.
Certain antibiotics, such as doxycycline, are quite effective. A long course of treatment, generally four weeks, is needed.
Control:
Control of ticks
Applying anti tick collars
Topical application of achrisides
