Borrelia miyamotoi Symptoms: What This Tick-Borne Disease Can Cause
Borrelia miyamotoi often causes a flu-like illness
Relapsing fever can occur in some patients
Severe neurologic complications are uncommon
Borrelia miyamotoi symptoms include fever, chills, headache, fatigue, muscle aches, joint pain, nausea, and occasionally relapsing fever. Unlike Lyme disease, a bull’s-eye rash is uncommon.
Although transmitted by the same Ixodes ticks that spread Lyme disease, Borrelia miyamotoi belongs to the relapsing fever group of Borrelia and causes a different infection.
Because the initial illness can be mild and nonspecific, some individuals with Borrelia miyamotoi disease may not seek medical care or may be diagnosed with another viral or tick-borne illness.
What are the symptoms of Borrelia miyamotoi disease?
Cleveland and colleagues explain that immunocompetent and otherwise healthy patients commonly develop a mild, flu-like illness characterized by fever, fatigue or excessive tiredness, chills, muscle and joint stiffness, aches and pains, and nausea.
Other reviews describe headache, myalgia, arthralgia, gastrointestinal complaints, and general malaise among the most frequently reported symptoms. Unlike Lyme disease, an erythema migrans or bull’s-eye rash is uncommon.
Symptoms generally begin approximately 10 to 18 days after a tick bite, although many patients do not remember being bitten.
Can Borrelia miyamotoi cause relapsing fever?
While uncommon, relapses of febrile episodes can occur. A patient may experience an initial episode of fever, improve for several days, and then develop another fever.
Relapsing fever is associated with the organism’s ability to change proteins on its surface, a process known as antigenic variation. These changes may allow the spirochete to temporarily evade the immune response.
However, relapsing fever is not reported in every patient. Early antibiotic treatment may also prevent additional febrile episodes from developing.
Can Borrelia miyamotoi affect the brain?
Most patients develop a nonspecific febrile illness without neurologic complications. However, immunocompromised individuals may experience reduced cognition, disturbed gait, memory deficits, confusion, and other neurologic problems associated with meningoencephalitis.
Additional reported findings have included hearing loss, weight loss, uveitis, iritis, neck stiffness, and sensitivity to light. These complications are uncommon but can be serious enough to require hospitalization.
Who is at risk for severe Borrelia miyamotoi disease?
The designation “immunocompromised” is broad. However, reports of severe Borrelia miyamotoi disease and meningoencephalitis have frequently involved patients receiving therapies that reduce B-cell function.
These therapies include rituximab and other cancer immunotherapies, as well as immunosuppressive medications used to treat rheumatoid arthritis and other inflammatory disorders.
Advanced age and an impaired antibody response may also increase the risk of neurologic disease. Nevertheless, there is no definitive list of medications or immune disorders that will predict which patients develop severe illness.
Does Borrelia miyamotoi cause a rash?
An erythema migrans rash is uncommon in Borrelia miyamotoi disease. A North American review reported erythema migrans in approximately 5% of documented cases.
Most patients never develop the classic bull’s-eye rash associated with Lyme disease. The absence of a recognizable rash can make the infection more difficult to identify.
Evaluation may therefore depend on symptoms, possible tick exposure, geographic risk, and appropriate laboratory testing.
How is Borrelia miyamotoi diagnosed?
The symptoms of Borrelia miyamotoi disease are nonspecific, so laboratory confirmation may be necessary. Testing methods include polymerase chain reaction (PCR), examination of a blood smear, and antibody testing.
PCR testing is generally most useful during the acute illness, when the organism is circulating in the blood and before antibiotics have been started. Antibody testing may become more useful later, after the immune response has had time to develop.
Antibody tests may be negative early in the illness because detectable antibodies have not yet developed. Testing may also be more difficult in immunocompromised patients whose antibody production has been reduced by illness or medication.
How is Borrelia miyamotoi treated?
Because formal treatment guidelines are limited, management is largely based on published clinical experience and recommendations for Lyme disease and relapsing fever borreliosis.
Doxycycline has commonly been used for uncomplicated infection in adults. Ceftriaxone has been used for patients with meningoencephalitis or other neurologic involvement.
Ampicillin, penicillin, azithromycin, erythromycin, tetracycline, and vancomycin have also been reported in the medical literature, either alone or in combination.
Laboratory studies have found that clinical and tick isolates of B. miyamotoi are susceptible in vitro to doxycycline, ceftriaxone, and azithromycin. One review reported in vitro resistance to amoxicillin, although laboratory susceptibility findings do not by themselves establish the best treatment regimen for an individual patient.
Can treatment cause a Herxheimer reaction?
Jarisch-Herxheimer reactions have occasionally occurred after antibiotic treatment for Borrelia miyamotoi disease.
This reaction can involve a temporary increase in fever, chills, headache, muscle pain, or other inflammatory symptoms shortly after treatment begins. Because worsening illness can have other causes, significant symptoms should be medically evaluated rather than automatically attributed to a Herxheimer reaction.
Frequently Asked Questions
What are the most common Borrelia miyamotoi symptoms?
The most common symptoms include fever, chills, headache, fatigue, muscle aches, joint pain, nausea, and malaise. Some patients also report gastrointestinal symptoms.
Does Borrelia miyamotoi cause relapsing fever?
Yes. Some patients experience an initial febrile illness followed by a period of improvement and then another fever. However, relapsing fever is reported in only a minority of recognized cases.
Is Borrelia miyamotoi the same as Lyme disease?
No. Borrelia miyamotoi is transmitted by the same hard-bodied Ixodes ticks that transmit Lyme disease, but it belongs to the relapsing fever group of Borrelia and causes a different infection.
Does Borrelia miyamotoi cause a bull’s-eye rash?
No. Most patients never develop the classic bull’s-eye rash associated with Lyme disease. Instead, they typically present with fever and other nonspecific flu-like symptoms.
Can Borrelia miyamotoi cause neurologic symptoms?
Rarely, Borrelia miyamotoi can be associated with meningoencephalitis, particularly in older or immunocompromised patients. Reported symptoms include confusion, memory problems, disturbed gait, neck stiffness, and sensitivity to light.
What is the incubation period for Borrelia miyamotoi?
Symptoms generally begin about 10 to 18 days after a tick bite, although many patients do not recall being bitten.
How is Borrelia miyamotoi treated?
Doxycycline is commonly used for uncomplicated disease in adults, while ceftriaxone has been used when meningoencephalitis or other neurologic involvement is present. Treatment should be individualized by a clinician.
Clinical Takeaway
Borrelia miyamotoi disease most often presents as a nonspecific flu-like illness with fever, chills, fatigue, headache, muscle aches, and joint pain. Relapsing fever can occur, while severe neurologic complications such as meningoencephalitis are uncommon and have been reported primarily in older or immunocompromised patients.
Early recognition and appropriate laboratory testing can improve diagnosis because the illness often resembles other viral and tick-borne infections.
Related Articles
Learn more about Borrelia miyamotoi, its diagnosis, and other illnesses transmitted by deer ticks.
What is Borrelia miyamotoi?
Doctors face challenges in diagnosing Borrelia miyamotoi
Tick-borne coinfections: Symptoms, diagnosis, and treatment
References
- Cleveland DW, Anderson CC, Brissette CA. Borrelia miyamotoi: A Comprehensive Review. Pathogens. 2023;12(2):267.
- Burde J, Bloch EM, Kelly JR, Krause PJ. Human Borrelia miyamotoi Infection in North America. Pathogens. 2023;12(4):553.
- Krause PJ, Fish D, Narasimhan S, Barbour AG. Borrelia miyamotoi Infection in Nature and in Humans. Clin Microbiol Infect. 2015;21(7):631-639.
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
