Borrelia miyamotoi Symptoms: Mild in Some, Severe in Others
Symptoms may be mild or missed
Flu-like illness is common
Severe neurologic disease can occur
Risk is higher if immunocompromised
Borrelia miyamotoi symptoms can range from mild flu-like illness to severe neurologic disease, depending on the patient’s immune status.
According to Cleveland and colleagues, immunocompetent individuals often present with relatively mild symptoms.
Mild Symptoms in Healthy Individuals
In otherwise healthy patients, symptoms often resemble a viral illness and may include:
- Fever and chills
- Fatigue and sleepiness
- Muscle and joint aches
- Nausea
Some patients may also experience relapsing fever episodes.
Symptoms can be mild enough that individuals do not seek medical care.
Severe Symptoms in Immunocompromised Patients
In immunocompromised individuals, Borrelia miyamotoi infection can be significantly more severe.
Neurologic complications may include:
- Reduced cognition and confusion
- Memory deficits
- Disturbed gait
- Meningoencephalitis
Additional reported symptoms include:
- Hearing loss
- Weight loss
- Uveitis and iritis
- Neck stiffness and photophobia
Some cases are severe enough to require hospitalization.
For neurologic overlap, see neurologic Lyme disease.
Who Is at Higher Risk?
The term “immunocompromised” includes a broad group of patients, but severe cases are most often reported in individuals:
- Receiving B-cell–depleting therapies (e.g., rituximab)
- Undergoing cancer immunotherapy
- Taking immunosuppressive medications for autoimmune conditions
These patients are at higher risk for neurologic complications.
Treatment Considerations
Several antibiotics have been used to treat Borrelia miyamotoi disease (BMD), including:
- Doxycycline
- Ceftriaxone
- Azithromycin
Other agents such as ampicillin and vancomycin have also been reported in treatment regimens.
Laboratory studies suggest:
- Susceptibility to doxycycline, ceftriaxone, and azithromycin
- Resistance to amoxicillin
Optimal treatment strategies are still being defined.
For broader tick-borne infections, see tick-borne coinfections.
Jarisch-Herxheimer Reaction
Although uncommon, Jarisch-Herxheimer reactions have been reported during treatment.
This reaction may include:
- Fever
- Worsening symptoms shortly after antibiotics begin
Patients should be monitored when starting therapy.
Clinical Takeaway
Borrelia miyamotoi symptoms can be mild and easily missed—or severe and neurologically significant.
Immunocompromised patients are at highest risk for complications.
Recognition of symptom patterns and appropriate treatment are essential to prevent serious outcomes.
Related Reading
- What is Borrelia miyamotoi?
- Challenges in diagnosing Borrelia miyamotoi
- Transmission of Borrelia miyamotoi
References
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
