Borrelia miyamotoi: What You Need to Know

Hard tick relapsing fever illness spread by deer ticks
Symptoms may overlap with Lyme disease
Testing and diagnosis remain challenging

Borrelia miyamotoi disease is a hard tick relapsing fever infection spread by the same deer ticks that transmit Lyme disease. Borrelia miyamotoi symptoms may include fever, fatigue, headaches, neurologic symptoms, and relapsing illness, often without the classic bull’s-eye rash seen in Lyme disease.

Because Borrelia miyamotoi infection can resemble Lyme disease and other tick-borne illnesses, diagnosis may be delayed or overlooked. Understanding its symptoms, testing limitations, and treatment approaches may help clinicians recognize this emerging infection earlier.

Clinicians evaluating patients with persistent symptoms after tick exposure may also consider related conditions discussed in the co-infections hub, especially when presentations do not fit classic Lyme disease patterns.

What is Borrelia miyamotoi disease?

Borrelia miyamotoi is a relapsing fever spirochete transmitted primarily through Ixodes ticks. Unlike Lyme disease, Borrelia miyamotoi disease generally does not produce an erythema migrans or bull’s-eye rash.

Borrelia miyamotoi belongs to the hard tick relapsing fever group of infections, which may explain the relapsing symptom pattern reported by some patients.

What is Borrelia miyamotoi?
What does Borrelia miyamotoi cause?
Could Borrelia miyamotoi infections explain persistent symptoms in Lyme disease patients?

Common Borrelia miyamotoi Symptoms

Common Borrelia miyamotoi symptoms may include:

• Fever
• Fatigue
• Headaches
• Chills
• Muscle aches
• Neurologic symptoms
• Relapsing episodes of illness
• Sleep disturbances

Symptoms frequently overlap with Lyme disease, babesiosis, viral infections, and other tick-borne illnesses.

Does Borrelia miyamotoi cause a rash?

Unlike Lyme disease, Borrelia miyamotoi disease usually does not cause an erythema migrans or bull’s-eye rash. The absence of a rash may contribute to delayed diagnosis.

Diagnosis and Testing

Testing remains challenging because routine Lyme disease tests may miss Borrelia miyamotoi disease. Diagnosis may depend on PCR testing, specialized antibody testing, exposure history, and clinical suspicion.

C6 peptide test may indicate Borrelia miyamotoi infection
Blood smear not reliable in diagnosing Borrelia miyamotoi disease
Doctors face challenges in diagnosing Borrelia miyamotoi
Don’t count on a relapsing fever to diagnose Borrelia miyamotoi
Where is the FDA test for relapsing fever spirochete, Borrelia miyamotoi?

Treatment

Treatment approaches often overlap with Lyme disease management, though delays in diagnosis may postpone treatment decisions and optimal management strategies remain an active area of study.

The best antibiotics to treat Borrelia miyamotoi?

Transmission

Unlike Lyme disease, Borrelia miyamotoi may be transmitted by larval ticks, potentially expanding exposure risk.

Borrelia miyamotoi can be transmitted from mother ticks to offspring
Study finds tiny larval ticks can transmit Borrelia miyamotoi
Larval ticks may be a threat after all — insights based on study of Borrelia miyamotoi
Move over nymphal ticks, larval deer ticks now pose a threat

Case Reports and Research

Case reports continue expanding understanding of neurologic disease, geographic spread, and atypical presentations.

Borrelia miyamotoi infection: An emerging tick-borne disease in California
Meningoencephalitis due to Borrelia miyamotoi
Borrelia miyamotoi detected in Canada
Review of Borrelia miyamotoi disease

Frequently Asked Questions

What symptoms are associated with Borrelia miyamotoi disease?

Symptoms commonly include fever, fatigue, headaches, chills, muscle pain, neurologic symptoms, and relapsing episodes of illness.

Does Borrelia miyamotoi cause a rash?

Unlike Lyme disease, Borrelia miyamotoi disease typically does not cause a bull’s-eye rash.

Can Borrelia miyamotoi symptoms come and go?

Some patients report relapsing episodes of illness, which differs from the more typical presentation seen with Lyme disease.

Is Borrelia miyamotoi the same as Lyme disease?

No. Borrelia miyamotoi disease is a different tick-borne infection caused by a relapsing fever spirochete, although it is spread by the same deer ticks that transmit Lyme disease.

How is Borrelia miyamotoi diagnosed?

Diagnosis may involve PCR testing, specialized antibody testing, exposure history, and clinical suspicion.

Clinical Takeaway

Borrelia miyamotoi disease can resemble Lyme disease while lacking hallmark findings such as a bull’s-eye rash. Testing limitations and overlapping symptoms may delay recognition.

Clinicians should consider Borrelia miyamotoi disease in patients with compatible symptoms, tick exposure, and negative or inconclusive Lyme testing.

Related Articles

Co-infections in Lyme disease
Why Lyme testing can miss infections
Persistent Lyme disease symptoms
Tick-borne diseases overview

References

1. Platonov AE, Karan LS, Kolyasnikova NM, et al. Humans infected with relapsing fever spirochete Borrelia miyamotoi, Russia. Emerg Infect Dis. 2011;17(10):1816-1823.
2. Molloy PJ, Telford SR 3rd, Chowdri HR, et al. Borrelia miyamotoi disease in the northeastern United States. N Engl J Med. 2015;373(3):240-245.

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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