Borrelia miyamotoi Infection: Symptoms, Testing, and Treatment
Borrelia miyamotoi is an emerging tick-borne infection transmitted by the same Ixodes ticks that spread Lyme disease. Although it was first identified in Japan in 1995, human infections have now been reported across North America, Europe, and Asia.
Because the same ticks transmit Borrelia burgdorferi and Borrelia miyamotoi, patients exposed to Lyme disease may also be exposed to this related organism. Increasing recognition of B. miyamotoi infection has highlighted the complexity of diagnosing tick-borne illness.
This page reviews the symptoms, testing challenges, and treatment of Borrelia miyamotoi infection.
What Is Borrelia miyamotoi?
Borrelia miyamotoi belongs to the relapsing fever group of Borrelia species rather than the Lyme borreliosis group. Despite this difference, the organism is transmitted by the same Ixodes ticks responsible for Lyme disease.
As a result, patients bitten by infected ticks may develop Borrelia miyamotoi disease (BMD), Lyme disease, or occasionally both infections at the same time.
Symptoms of Borrelia miyamotoi Infection
Patients with Borrelia miyamotoi disease often present with flu-like symptoms rather than the classic Lyme disease rash.
Common symptoms may include:
- Fever
- Chills
- Headache
- Fatigue
- Muscle aches
Laboratory abnormalities such as leukopenia or thrombocytopenia may also occur and can help distinguish this infection from Lyme disease.
Challenges in Diagnosing Borrelia miyamotoi
Diagnosing Borrelia miyamotoi infection remains challenging. Unlike Lyme disease, there is currently no widely available FDA-approved serologic test specifically designed to detect this organism.
Because the infection occurs in the same geographic areas as Lyme disease, clinicians often rely on indirect diagnostic clues.
For example, research suggests that the C6 peptide ELISA used for Lyme disease testing may also detect antibodies produced during Borrelia miyamotoi infection.
A pattern of a positive C6 ELISA with a negative Lyme Western blot may therefore suggest possible Borrelia miyamotoi infection.
Other diagnostic approaches include PCR testing and detection of the glycerophosphodiester phosphodiesterase (GlpQ) gene.
Co-infection With Lyme Disease
Because Borrelia miyamotoi and Borrelia burgdorferi are transmitted by the same ticks, co-infection is biologically plausible.
Patients may therefore present with overlapping symptoms or laboratory findings.
Understanding these overlapping infections is part of the broader challenge of tick-borne coinfections and the limitations of current diagnostic testing.
Treatment of Borrelia miyamotoi
Most patients with Borrelia miyamotoi infection respond to antibiotics commonly used to treat Lyme disease.
Doxycycline is typically effective, although treatment decisions should always be guided by the patient’s clinical presentation and medical history.
Early recognition and treatment generally lead to good outcomes.
Clinical Perspective
Recognition of Borrelia miyamotoi infection highlights the complexity of diagnosing tick-borne illness.
Patients evaluated for Lyme disease may actually have infection with related organisms transmitted by the same tick vectors. Awareness of these infections can help clinicians avoid missed diagnoses and better interpret confusing laboratory test results.
