A New Strain of Tick-Borne Disease

Dog owners should be aware of this new strain of the tick-borne disease Rikettsia.


I’m just back from a week’s vacation, wherein my husband and I picked up his grandson from a suburb of Boston and drove to Gettysburg National Military Park in Pennsylvania to indulge in said grandson’s fascination with the Civil War. We took a hike in Connecticut (on the way) and took several hikes all around the battlegrounds of Gettysburg, on wide, gravel trails and small, forested paths alike. One night in our hotel, after walking all over the hills and trails in Gettysburg, I felt something crawly and found a big dog tick walking along my forearm. Ack! I flushed the tick down the toilet and told my husband and grandson to be alert for ticks on themselves, too.

I honestly thought no more about it until this morning, when I read a 2021 article that a Pennsylvania friend had just shared about the detection of a new strain of Rikettsia, a potentially deadly disease affecting both dogs and people. The new strain of this tick-borne disease was first detected in a handful of dogs who either lived in or had recently visited southern states. I was not bitten by the tick, so I know I don’t have to be worried for myself, but any new tick-borne disease is bad news that dog owners in particular should be aware of.

Ticks can carry quite a few pathogens that can cause disease in dogs and humans. Some of these pathogens are viruses, some are bacteria, and some are protozoa (single-celled animals). Rikettsia are very small bacteria species that grow inside the living cells of their hosts. Different strains of Rikettsia are responsible for diseases such as Rocky Mountain Spotted Fever and various strains of typhus.

The new strain of Rikettsia has likely been around for a while, but researchers identified it as a novel species only in 2020, after obtaining laboratory samples from tests conducted on dogs who had been diagnosed in 2018 and 2019 with Rikettsial diseases and certain symptoms (fever and specific hematological abnormalities). Researchers obtained DNA gene sequences from canine blood specimens that were seroreactive for R. Rickettsia and found identically unique genetic markers in samples from three dogs who had been bitten by ticks in three different states (Tennessee, Arkansas, and Oklahoma). After extensive analysis, it was determined that these three dogs had been affected by identical and never-before identified strains of Rickettsia. Additionally, the new strain was found to be related to two strains of Rickettsia that affect humans (R. heilongjiangensis and R. massiliae). The researchers concluded that this unique Rickettsia species has clinical significance for dogs and potentially humans. The disease caused by this species, they warn, could be underdiagnosed and geographically widespread.

The good news is that this strain, like other Rikettsia species, can be successfully treated with the antibiotic doxycycline; sometimes, more than one course of treatment is required. However, this presumes prompt detection of the infection (via PCR test for Rikettsia). Sometimes, dog owners need to push for this testing, as TBDs are not always the first thing that comes to mind when vets are faced with the varied array of symptoms and biochemistry abnormalities that TBDs can cause. Sometimes, additional medications ar required to treat side effects. For example, one of the three dogs whose novel infections were first detected (a Boston Terrier who lived in Illinois, but apparently got bitten by an infected tick on a trip to Arkansas) was treated with doxycycline to treat his rickettsiosis, prednisone to treat potential immune-mediated component, omeprazole to prevent gastric ulcers (doxycycline can be notoriously hard on a dog’s digestive tract, causing many dogs to stop eating during treatment), and metronidazole to treat “assumed dysbiosis” (disruption to the microbiota homeostasis caused by an imbalance in the microflora, i.e., super upset gut balance caused by the doxycyline).

Some readers of WDJ have complained that we promote the use of topical pesticides that repel and/or kill ticks (such as this recent one that listed all of the better flea and tick preventatives currently on the market). In truth, we want dog owners to know as much as possible about the tools that are available, so they can choose appropriate tactics for protecting their dogs from fleas and ticks, based on their dogs’ individual health conditions and environment. We do not advocate for pesticide use on all dogs, but we do want owners to be aware of the risks of failing to adequately protect the dogs who are at high risk of parasites and the deadly diseases that they (ticks in particular) carry. Tick-borne diseases are widespread, varied, and, left undiagnosed or inadequately treated, capable of making humans and dogs alike very ill – even killing them. It’s critical to prevent your dog’s exposure to ticks – and to get your dog tested for tick-borne diseases if he develops any symptoms of lethargy, fever, lameness, or lack of appetite after being exposed to ticks.






  1. In my hometown (Tunkhannock, Pennsylvania) the black-legged ticks, more commonly known as a deer ticks, have tested positive for deer tick virus (DTV). I have yet to find anything that states whether or not canines are affected, and if so, how severely. This is very concerning!

    • You’re absolutely correct! Thanks for mentioning that! Adding that now. We’re fortunate in that it responds to doxycycline, the same antibiotic that works for many of the TBDs.

  2. My son had Lyme several years ago. It went undiagnosed for 2 or 3 months while he and his doctor tried to figure out what was wrong with him. I asked if they checked for Lyme, since he had been bitten by ticks. They checked and got “lucky” that it showed up. However, 2 rounds of doxycycline did not clear it up. The AMA does not recognize chronic Lyme Disease, but it exists. My son had it. After months of trying to get treated, we finally found a doctor that specialized in Lyme Disease. The treatment, several weeks of intravenous antibiotics, caused a lot of problems as your body throws off the disease. If not caught quickly, Lyme causes arthritis and nerve damage.

    What I am saying is, don’t mess around with ticks. Be aware if you get a bite. If you start running a fever, get checked! And, I know insecticides are not good for our persons, pets, or planet, but Lyme Disease is worse. Make your choice. Spray your yard or risk a loved one. But, do check for ticks!

    • If you spread Diatomaceous Earth over your yard it will kill ticks and fleas. It has to be the white DE from pool supplies. The powder has barbs that penetrate the insects outer shell that allows bacteria and fungus in that kills them. Apply DE over your yard when there will be a few dry days. That will give the insects a chance to walk through the powder. D E is for swimming pool filters. Apply again after rain and when the yard is dry. Rain washes it into the soil so it becomes useless. I’ve used it for 25 years. I use Advantix 2 also.

  3. Most times you have good articles, but sometimes not so, like this one. If you’re going to talk about something, (like a tick), talk about it. Say what states it’s in, symptoms, any cure, etc., not your vacation.

    • Thanks for the feedback. If it helps, this one page (posted under the tab “Blog” at the top of the page) is my blog, where I do share more personal things about my dogs and my life with dogs as they come up. The posts on this page and my monthly editorial are the only pages where I might share details about things like ticks found on vacation. All the rest of our content are straight-up articles. Hope that helps.

  4. It’s a shame we’re living in a time in which we see pharmaceutical companies, supported by their captured agents in the government, working hard to create and fan the flames of fear with a seemingly endless string of discoveries of “new“ and “novel“ diseases. Coincidentally, they just happen to have pharmaceutical remedies for all of these. Thanks, but information such as this comes with great suspicion now.

    • Well said. We wonder who is behind the latest danger to both people and pets, in this case the tick borne outbreaks and subsequent diseases….hmmm….And has anyone seen and heard the recordings of representatives of the wef and its associated organizations, talking about how we need to be afraid of our pets? Did you catch a recent ”news” report that circulated nationally, regarding how we should stop cuddling our pets and cease allowing our pets to give us kisses?

  5. Thanks for the heads-up about this new strain. I live in a rural area and have to check my dogs and myself for ticks daily, even during colder weather. I’m pretty sure the nasty buggers would survive a nuclear strike!

  6. My dog just had her annual 4DX which came back negative. I assume since this is a new disease, it would not be detected via the 4DX? Thanks for alerting us to this new disease.

    • There are blood (seroreactive) tests that look specifically for antibodies to any Rikettsia species; a PCR test (which looks for the DNA of any Rickettsia species) will also detect it.

      The 4Dx test is a seroreactive test that can detect antibodies that indicate infection with heartworms, Borrelia burgdorferi (the bacteria that causes Lyme disease), Anaplasma phagocytophilum and Anaplasma platys (the bacteria that cause anaplasmosis), and Ehrlichia canis and Ehrlichia ewingii (the bacteria that cause ehrlichiosis). So a 4Dx test would NOT detect this infection. If a dog is displaying symptoms of any TBD and has been present in an area where ticks are known to be found, ask your vet for a blood test that specifically looks for antibodies to Rikettsia or a PCR test.

  7. Thank you for sharing this great information! My preferred method of tick disposal is transparent sticky tape (Scotch tape). It immobilizes the tick and then I toss it in the trash. I keep a roll in my garage and in my car’s glove compartment, ready for the tick check upon returning from our daily walks and hikes. More convenient than toilets, especially if they are none nearby. And I read that ticks can survive total submersion in water for hours without dying.


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