Signs of Tick Fever in Dogs

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Tick fever vaccines don't exist, but tick preventives do.
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Canine ehrlichiosis, also known as tick fever, is an infectious disease that dogs contract via bites from Lone Star ticks (Amblyomma americanum) and brown dog ticks (Rhipicephalus sanguineus). Tick fever occurs in domestic dogs and their wild counterparts all around the globe.

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Defining Tick Fever

Tick fever is a Rickettsia infection brought upon by the organisms Ehrlichia lewinii and Ehrlichia canis. Lone Star ticks and brown dog ticks introduce the bacteria that bring upon these infections. Rickettsia bacteria take up residence in white blood cells and wreak havoc.

Ticks feed on canine blood. When brown dog ticks and Lone Star ticks bite their victims, they transfer Ehrlichia organisms to the hosts' bloodstreams. This is how dogs contract tick fever.


Both dogs and cats are susceptible to transmission of tick fever. Although highly uncommon, human beings are sometimes prone to catching ehrlichiosis, as well. Doberman pinschers and German shepherds are two canine breeds that generally experience more intense and dramatic effects of this infection.

Stages and Symptoms

Tick fever appears in three distinct phases. These phases are acute, sub-clinical and chronic. If a dog has acute tick fever, he'll experience symptoms such as respiratory troubles, swollen lymph nodes, loss of weight, fever, bleeding problems and neurological issues. Acute symptoms appear in the beginning stages of tick fever, generally in the springtime and summertime.


When dogs are in the sub-clinical stage of tick fever, they display zero indication of the disease and therefore don't exhibit symptoms. If your dog possesses a good immune system, he could potentially fight off tick fever during the sub-clinical period.

If your canine's body doesn't conquer ehrlichiosis, he'll move on to chronic infection, which is the disease's third phase. A dog in the chronic phase might display severe symptoms such as anemia, vision difficulties -- eye hemorrhaging is one example -- lameness, uncontrollable bleeding, limb swelling, and failure of the bone marrow. Some dogs experience thrombocytopenia, a health condition characterized by low blood-platelet counts. Dogs with chronic ehrlichiosis sometimes succumb to the ailment.


Veterinary Assessment and Management

Veterinarians sometimes have a hard time diagnosing canines in the beginning of tick fever infection because the canine immune system requires roughly two to three weeks to react to the organisms and establish antibodies. When several weeks have passed after dogs have contracted tick fever, veterinarians can detect the disease by conducting tests that look for antibodies. Vets diagnose dogs with tick fever based on the results of blood tests and on symptoms. If you spot engorged ticks on your pet, remove them and note the date; a blood test will be in order about eight weeks later.


If the vet determines that your dog has tick fever, he might treat the dog with antibiotics such as doxycycline and tetracycline. Treatment generally takes between three and four weeks. If a dog has a particularly intense case of tick fever, he might require intravenous fluid or a blood transfusion. If your dog receives treatment when he's in the acute phase, recovery chances are usually strong. If he receives treatment when he's in the chronic stage, his recovery odds are lower.

Protection Against Tick Fever

Speak to your veterinarian about finding a tick control option to kill and drive away ticks. Tick control products that include permethrins are often a good idea. Many veterinary clinics suggest monthly tick control. There are collars, ingestibles, dips, topicals and shampoos.


Some veterinarians suggest stopping tick fever in dogs by giving them low doxycycline or tetracycline dosages during tick season. This is common for dogs who reside in regions that have significant tick fever occurrence.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.