What Is Borrelia miyamotoi? Symptoms, Testing, and Treatment
Borrelia miyamotoi is an emerging deer tick infection
Symptoms overlap with Lyme disease and other tick-borne illnesses
Testing and treatment remain challenging
Borrelia miyamotoi (B. miyamotoi) was first reported in the United States in 2013 but has become increasingly recognized as an emerging tick-borne illness. The infection can be transmitted by the same deer tick that carries Borrelia burgdorferi, the Lyme disease pathogen. In their article, Della-Giustina and colleagues address the question, “What is Borrelia miyamotoi?” and concerns surrounding this growing threat.
Borrelia miyamotoi belongs to the relapsing fever group of Borrelia species and may present with symptoms that overlap with Lyme disease, anaplasmosis, and other tick-borne coinfections.
Where is Borrelia miyamotoi found?
Borrelia miyamotoi can be found in several tick species including the deer tick. It has been detected in ticks located throughout the northeastern and northern Midwestern United States, California, Europe, and Asia.
This growing geographic distribution has raised concerns because deer ticks can transmit multiple pathogens simultaneously, contributing to the expanding list of diseases carried by deer ticks.
What stage of deer ticks transmit Borrelia miyamotoi?
Borrelia miyamotoi can be transmitted during multiple tick life stages including the larval stage.
Unlike Lyme disease, larval ticks may already carry the organism because infected adult ticks can pass the pathogen directly to offspring through transovarial transmission.
How fast can Borrelia miyamotoi be transmitted?
Transmission appears to occur rapidly.
The authors explain that B. miyamotoi may be transmitted 10% of the time within the first 24 hours of attachment, increasing steadily to 73% with complete feeding.
This faster transmission pattern differs from traditional discussions surrounding Lyme disease transmission time.
What are Borrelia miyamotoi symptoms?
Borrelia miyamotoi symptoms may overlap considerably with Lyme disease and other tick-borne infections.
Symptoms reported in case series include:
- Fever
- Malaise
- Headache
- Muscle aches
- Fatigue
- Elevated liver enzymes
- Low white blood cell counts
Some laboratory abnormalities overlap with findings commonly associated with anaplasmosis.
Only about 11% of patients in one case series developed an erythema migrans rash.
How is Borrelia miyamotoi diagnosed?
Borrelia miyamotoi testing remains challenging.
The authors note that no test specific for Borrelia miyamotoi had received FDA approval as of October 2020.
The most specific testing currently available includes PCR testing of blood or cerebrospinal fluid targeting the GlpQ enzyme.
Serologic IgM and IgG testing is available through selected commercial laboratories, although interpretation may be difficult because cross-reactivity with other spirochetes remains possible.
Novel testing approaches including array-based assays such as the TBD Serochip have been proposed but remain limited in availability.
Testing limitations overlap with broader concerns about tick-borne disease test accuracy.
What is the treatment for Borrelia miyamotoi?
Borrelia miyamotoi treatment remains uncertain because evidence-based treatment trials are lacking.
Doxycycline has been commonly suggested because patients with Lyme disease and relapsing fever Borrelia infections often respond clinically.
In vitro studies have shown susceptibility to:
- Doxycycline
- Ceftriaxone
- Azithromycin
The authors also reported resistance to amoxicillin in laboratory testing.
Because treatment evidence remains limited, management often relies on extrapolation from related tick-borne infections.
Should prophylactic treatment be considered?
Because transmission may occur rapidly, some clinicians have questioned whether prophylactic treatment decisions should differ from standard Lyme disease approaches.
The authors suggest that rapid transmission may warrant considering earlier intervention in endemic areas, although evidence remains limited.
What are the limitations of current knowledge?
- Few prospective treatment studies exist
- Testing remains limited and difficult to interpret
- Symptoms overlap with multiple tick-borne illnesses
- Transmission estimates vary between studies
- Optimal treatment duration remains uncertain
Frequently Asked Questions
What is Borrelia miyamotoi?
Borrelia miyamotoi is a relapsing fever Borrelia species transmitted primarily by deer ticks.
What are Borrelia miyamotoi symptoms?
Symptoms may include fever, fatigue, headaches, muscle pain, abnormal laboratory findings, and flu-like illness.
How is Borrelia miyamotoi treated?
Doxycycline is commonly used, although evidence-based treatment trials remain limited.
How is Borrelia miyamotoi tested?
PCR testing targeting GlpQ and selected serologic assays are currently used.
Can deer ticks spread Borrelia miyamotoi?
Yes. Deer ticks can transmit Borrelia miyamotoi and may transmit it more rapidly than Lyme disease bacteria.
Is Borrelia miyamotoi Lyme disease?
No. It is a different Borrelia species, although symptoms and tick vectors overlap.
Clinical Takeaway
Recognition of Borrelia miyamotoi remains important because symptoms overlap substantially with Lyme disease and other tick-borne infections.
Rapid transmission, limited testing options, and overlapping symptoms make Borrelia miyamotoi an emerging diagnostic challenge for clinicians and patients.
Related Articles
These articles explore tick-borne coinfections, testing limitations, and overlapping deer tick diseases.
Could Borrelia miyamotoi infections explain persistent symptoms?
C6 peptide test may indicate Borrelia miyamotoi infection
The best antibiotics to treat Borrelia miyamotoi
Babesia and overlapping tick-borne infections
Delayed Lyme disease diagnosis
References
- Kadkhoda K, Dumouchel C, Brancato J, Gretchen A, Krause PJ. Human seroprevalence of Borrelia miyamotoi in Manitoba, Canada, in 2011-2014: a cross-sectional study. CMAJ Open. 2017;5(3):E690-E693.
- Della-Giustina D, Duke C, Goldflam K. Underrecognized Tickborne Illnesses: Borrelia Miyamotoi and Powassan Virus. Wilderness Environ Med. 2021;32(2):240-246.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
My son was tested by the Columbia Lyme research team positive for Miyamotoi. He also has Bartonella. There is no known time of rash. He has been suffering from encephalopathy over last five years. Treated oral Doxy, then IV Ceftriaxone and Azithromycin. Has had IVIG last three years and added Plasmapheresis 8 months ago. Much better but still many issues and unable to fully function. He is now 21 years old..