Borrelia miyamotoi (TBRF)
Name(s) of illness: Borrelia miyamotoi infection, Tick-borne Relapsing Fever (TBRF), Borreliosis
Caused by: infection with Borrelia miyamotoi, a species of bacteria that can be transmitted through the bite the following hard-bodied ticks: Ixodes scapularis (deer tick), Ixodes pacificus (western blacklegged tick), Ixodes ricinus (castor bean tick), and Ixodes persulcatus (taiga tick). (The first two tick species listed are common in North America, and the second two are found in Europe and Asia.) Borrelia are spirochetes, which means they have spiral-shaped cells. Borrelia miyamotoi is unique because although it is genetically more similar to Borrelia species in theRelapsing Fever Borrelia group, it is carried by the same ticks that transmit the bacteria in the Lyme Borrelia group. Borrelia miyamotoi was discovered (in ticks and mice) in Japan in 1995, and was subsequently documented in U.S. ticks in 2011. Cases of human infection were first documented in Russia in 2011.
Symptoms of infection: episodes of fever lasting several days, followed by an interval without fever, followed by another episode of fever. This process can recur from 1 to 4 times. Along with fever, patients may experience generalized body aches, muscle pain, joint pain, headache, nausea, vomiting, anorexia, dry cough, light sensitivity, rash, neck pain, eye pain, confusion, and dizziness.
Long-term effects: patients with untreated or improperly treated infections can develop chronic fatigue, joint and muscle pain, and joint deterioration. Extreme episodes of fever can be fatal. Other long-term problems include iritis/uveitis (inflammation of the iris), cranial nerve and other neuropathies. A 2012 study of 50 Russian patients revealed “signs of functional impairment of various organs: the liver (in about half of the patients), kidney (in 10 patients), [and] heart (6 patients).”
Diagnostic tests: In peer-reviewed studies, B. miyamotoi has been detected using PCR (of cerebrospinal fluid), ELISA, and Western Blot assays. Antibody tests were designed to be specific to B. miyamotoi by detecting antibody to the GlpQ protein (which is not present in B. burgdorferi). Currently, most physicians in the United States do not have access to tests for B. miyamotoi. Patients with B. miyamotoi are likely to test negative on a Western Blot for B. burgdorferi (Lyme disease), but may test positive on a Borrelia hermsii antibody IFA, due to crossreactivity.
Treated: orally with doxycycline. Latent (long-term) infections, especially when there are neurologic symptoms, are treated with an IV drip of Ceftriaxone 2 grams per day for anywhere from 10 to 42 days, depending on the physician.
Diagnosis/treatment controversies: Borrelia miyamotoi infection in humans was not documented until 2011, and because these cases were in Russia, many U.S. physicians are not very aware of this infection. B. miyamotoi made U.S. headlines in January of 2013 following the documenting of infection in American patients by a group of New England researchers that includes Dr. Peter Krause, Dr. Gary Wormser, and Dr. Alan Barbour. Needless to say, many patients infected with B. miyamotoi are likely being misdiagnosed (or not diagnosed at all) and going untreated because they have only been tested for Borrelia burgdorferi (Lyme disease). We can predict that as laboratory tests for B. miyamotoi become more widely available, the number of documented cases in the U.S. (and worldwide) will rise dramatically.
Recommended reading:
The CDC’s page on Tick-borne relapsing fever
Human Borrelia miyamotoi Infection in the United States (New England Journal of Medicine)
Humans Infected with Relapsing Fever Spirochete Borrelia miyamotoi, Russia
Meningoencephalitis from Borrelia miyamotoi in an Immunocompromised Patient (NEJM)
Paper documenting Fukunaga et al’s 1995 discovery of Borrelia miyamotoi in Japan
Paper documenting clinical presentations (symptoms) of 50 Russians patients with B. miyamotoi
THE TICK THAT BIT ME 
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