What does Borrelia miyamotoi cause?
Borrelia miyamotoi is a co-infection that can be transmitted by the same tick that carries Lyme disease. B. miyamotoi can lead to Borrelia miyamotoi disease (BMD). In their article “Borrelia miyamotoi: A Comprehensive Review,” Cleveland and colleagues reviewed the clinical manifestations of BMD. 
The authors explain, “Immunocompetent, and otherwise healthy, patients present with milder, flu-like symptoms: fever, fatigue, sleepiness, chills, muscle and joint stiffness, aches and pains, and nausea.” And, “While uncommon, relapses of febrile episodes can occur.”
In fact, the symptoms may be mild enough that an individual with Borrelia miyamotoi disease may not seek medical care.
However, immunocompromised individuals may experience not only flu-like symptoms but reduced cognition, disturbed gait, memory deficits, confusion, and other neurological deficiencies resultant of meningoencephalitis, wrote Cleveland and colleagues.
“Additionally, hearing loss, weight loss, uveitis, iritis, neck stiffness, and photophobia have been reported,” the authors wrote.
The symptoms can be severe enough is some patients that they require hospitalization.
Who is immunocompromised?
Although the designation of ‘immunocompromised’ is broad, the authors point out, there are several cases which fit into this category. “Hospitalization reports of severe BDM are frequently seen in patients prescribed B-cell depletion therapies, such as rituximab, other cancer immunotherapeutics, or immunosuppressants for rheumatoid arthritis.”
There are several proposed treatments for BMD. Doxycycline and ceftriaxone have been prescribed given their use in relapsing fever. “Ampicillin, azithromycin, and vancomycin, or a combination thereof, have also been used to treat BMD,” wrote Cleveland and colleagues.
However, the jury is still out. “Research has confirmed in vitro that both clinical and tick isolates of B. miyamotoi are susceptible to doxycycline, ceftriaxone, and azithromycin, but show resistance to amoxicillin.”
“Albeit rarely, Jarisch-Herxheimer reactions have occurred with antibiotic treatment of BMD,” the authors point out.
- Cleveland DW, Anderson CC, Brissette CA. Borrelia miyamotoi: A Comprehensive Review. Pathogens. Feb 7 2023;12(2)doi:10.3390/pathogens12020267