Erlichiosis: All You Need To Know

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Ehrlichiosis is a group of tick-borne diseases that can cause devastating effects on the immune system and overall health in general. It has a variety of different names that it is known by, including canine hemorrhagic fever, canine rickettsiosis, canine typhus, tracker dog disease, and tropical canine pancytopenia.

Even though several species are in existence, the most common form is Ehrlichia Canis or Canine Ehrlichia.


How does an animal contract Ehrlichia?

Ehrlichiosis is a disease that develops once the host has been bitten by an infected brown dog tick. While some animals may acquire the disease without any symptoms or effects, others will develop troubling symptoms, and can possibly become gravely ill.

Another manner in which a dog can develop Ehrlichia is when it receives a blood transfusion from a dog that has already been infected.

It is important to note that humans can also contract Ehrlichia, but it is not passed down from animal to human. The brown dog tick passes this disease down to humans as well.

The tick secretes a sticky substance that allows them to attach to the host, allowing them to feed and mate successfully in the process. The ticks prefer warmer temperatures and is widespread in the United States, especially in regions such as California.

The ticks are identifiable by their reddish-brown color – which is where the name also comes from.

What are the symptoms of Ehrlichiosis?

There are three stages of Ehrlichiosis:

  • Acute (early disease)
  • Clinical or chronic (long-standing infection), and
  • Sub-clinical (no outward signs of disease.)

The Acute Stage starts manifesting between one to three weeks after infection has taken place and can last between two to four weeks. This stage is also more widespread in the Spring and Summer seasons.

Most dogs are often seen in the acute stage of the illness, as this stage presents the sudden and alarming symptoms. These symptoms include:

  • Lethargy
  • Fever
  • Anorexia
  • Vomiting
  • Diarrhea
  • Bleeding disorders (Anemia, Coagulopathies, bleeding episodes, etc)
  • Swollen lymph nodes
  • Weight loss
  • Neurological symptoms (incoordination, paralysis, etc)
  • Seizures

The sub-clinical phase can be present for the remainder of the dog’s life. The sub-clinical phase of this disease will display no symptoms, but the organism will be present in diagnostic testing. This phase of the disease often leaves pets undiagnosed, due to no specific reason to test for the illness.

During the chronic or clinical phase (phase three), some prevalent indications which are both recurring and hematological are:

  • Thrombocytopenia (Low blood platelet count)
  • Depression
  • Petechiae (Purple, red or brown spots on the skin)
  • Edema (Swelling from excess body fluid build up)
  • Pale mucous membranes
  • Eye problems
  • Lameness

Unfortunately some dog breeds, such as German Shephards and Huskies are more susceptible to contracting this disease, and sadly they can suffer severe clinical effects.

Did you know that your dog can carry Ehrlichia antibodies for up to four years? This means that every time a test is performed, your furry friend may in fact test positive, resulting in uncertainty as to whether this is a new infection or a pre-existing infection from a previous occasion.

The clinical signs in humans include symptoms such as:

  • Aches and pains in the ocular (eye) region
  • Fever
  • Headaches
  • Upset stomach

In most cases, the infected human will start to experience flu-like symptoms within one to two weeks after being bitten. A full recovery for humans can be expected in three weeks. It is to be noted that the cases in humans are rising each year, and can be eradicated by treated your pets regularly.

How can you test for Ehrlichiosis?

When testing for Ehrlichiosis, it’s important to know that antibodies for the disease may not be present until about 2-3 weeks after infection. Testing performed a few weeks after exposure will allow the antibodies to be detected during an in-clinic snap test (4DX), or sending a sample to the lab for ELISA testing.

Although it is less common, the organism can sometimes be seen on a blood smear or in samples of cells taken from various organs in the body.

How is Ehrlichia treated?

The recommended course of treatment for Canine Ehrlichiosis is a 3-5 week course of the antibiotic Doxycycline.  The Ehrlichia tends to respond very quick to the Docxycyline treatment, but your dog would have to endure a long course thereof to ensure its full recovery.

Though a course of antibiotics is needed to eradicate the bacteria, some pets may still require other supportive care. Due to the potential of Anemia and other bleeding disorders, some patients will require blood transfusions to pull them out of the crisis.

Animals that are dehydrated may receive treatment such as IV fluids and in the more severe cases, steriods might be the best course of action to take due to the blood platelet count being extremely low.

Tetracyline at a lower dose can be administered for a course spanning 200 days during tick season or in areas where the disease is rife.

How can you prevent Ehrlichiosis?

The only way to prevent Caine Ehrlichiosis is through the prevention of ticks in general. While you cannot contract Ehrlichia directly from your pet, you can contract Ehrlichiosis from the infected ticks that your pet may carry. Talking to your veterinarian about reliable tick prevention for your pet can help to prevent exposure to the bacteria.

Ideally, prevention is better than cure and regular tick preventative measures needs to be put into place, especially in the seasons and environmental conditions when the tick eggs hatch.

Get into the habit of checking your dog regularly by inspecting their fur when they are peacefully lying next to you. Topical treatments such as Frontline can greatly aid in the safeguard against this illness.

Other preventative care includes the regular washing of pet blankets and disinfecting the places where they sleep and lie.

If you learned anything from this article, take a look at our article about Dog ticks, and learn about the different types of ticks that you may see on your pet.

We owe a lot to our pets seeing as they serve as sentinels or indicators that there is a tick problem in the area. We as humans owe it to them to protect them against it.

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Amber, a dedicated animal enthusiast, has seamlessly merged her passion for animals with her career as a Licensed Vet Tech and content creator. Her journey is a testament to her commitment to educating pet parents through informative articles. With a degree in Veterinary Technology, she has become a prolific writer and a professional dog trainer. Amber's expertise spans veterinary medicine, pets, and shelter medicine. Her Amazon published book, "Heal My Fractious Heart - A Vet Med Romcom," showcases her creative writing talents. Currently residing in Chiang Mai, Thailand, she manages marketing and social media for a preventive pet health subscription company called Vetted.