What is ehrlichiosis?
Ehrlichiosis is a tick-borne disease that affects dogs. There are several strains of Ehrlichiosis which affect different species of animals and people. Ehrlichiosis in dogs is most commonly caused by Ehrlichia canis, E. chaffeensis, E. ewingii, and E ruminantium. The ehrlichia organisms are otherwise labeled as rickettsia, which is between a bacteria and a virus.
How is ehrlichia transmitted?
Ehrlichia is transmitted by ticks, including Brown Dog Tick, Rhipicephalus sanguineus, and Lone Star Tick. An immature tick feeds on an infected animal. When an immature or mature form of the tick feeds on another animal, Ehrlichia is passed on to the bitten animal. Ehrlichia can remain in the tick for up to 5 months, which means a tick could become infected in fall, and infect a dog the following spring.
What are symptoms of ehrlichiosis?
Acute phase
The acute phase lasts between 2-4 weeks. In this phase, the Ehrlichia enter white blood cells and reproduce from within. These cells are also found in the liver, spleen, lymph nodes, and bone marrow. As a result, these areas are often enlarged and infected. Platelets, which are small cell fragments that help blood to clot, are often destroyed as well. Symptoms include fever, lethargy, loss of appetite, anemia, depression, shortness of breath, joint pain and stiffness, and bruising. If a dog does not fight off the infection at this stage, it progresses to the subclinical phase.
Subclinical phase
The subclinical phase can last from months to years. During this time, a dog may appear normal or show slight signs of anemia. At this time the Ehrlichia lives inside the spleen and ultimately over time the dog’s body eliminates the Ehrlichia from the body or the infection progresses to the chronic phase.
Chronic phase
The chronic phase is when one cell type, the lymphocyte, may increase or appear abnormal. Symptoms include weight loss, anemia, neurological signs, bleeding, inflammation of the eye, fluid accumulation (edema) in the hind legs, and a fever. If a dog reaches the chronic phase, the disease can keep coming back during peaks of stress. It may also develop into arthritis, or a kidney disease called glomerluonephritis. German Shepherds and Doberman Pinschers are more susceptible of it reaching the chronic phase.
How is ehrlichiosis treated?
Antibiotics tetracycline or doxycycline are prescribed over a 3-4 week period, even though a dog’s symptoms may improve after several days of therapy. Some dogs require blood transfusions or intravenous fluids depending on severity. The general prognosis at the acute phase is good with proper treatment. Dogs that reach the chronic phase have a poorer prognosis. Specifically, German Shepherds and Doberman Pinschers are most prone to have a more severe chronic form of the disease.
How can I prevent ehrlichiosis?
First and foremost, tick control. Products geared towards repelling and killing ticks that contains permethrins are top choices. Tick collars containing the active ingredient amitraz are also used in conjunction with permethrin products in areas with high tick infestations. Read our article on tick-borne diseases in the local area to know severity. As of right now, there is no vaccine for ehrlichiosis.
Can humans get ehrlichiosis?
Yes, but not directly from a dog. However, it is the same process as for a dog, in that it is through a tick bite. The most often Ehrlichia species that affects humans is E. chaffeensis. Symptoms in humans infected by ehrlichiosis include fever, chills, headache, and muscle aches.
If you sense a change in your dog’s behavior, book an appointment immediately with your vet. In any situation, sooner is better than later in regards to your pet’s health.