Monday, February 24, 2014

Borrelia miyamotoi

Recently I've read the following campaign: "Warning - ticks may cause double trouble". The campaigne is about a tick borne vector called Borrelia miyamotoi. Borrelia burgdorferi causes Lyme disease and so the concern for a new Borrelia species is quite understandable. In 2013 the first Borelia miyamotoi infection in a human has been diagnosed in the U.S. There were only symptoms like fever, chills, and headache; and we can only speculate about the potential of Borrelia miyamotoi for further impacts on health.
The CDC (Centers for Disease Control) have the following information:
* Borrelia has been first identified in 1995
* human infections were first described in Russia in 2011
* there were three cases in the U.S. until now
* PCR-tests for B. miyamatoi aren't yet available, though development of these test in under way
* tests for B. burdorferi are unlikely to be of help to detect a B. miyamotoi infection
* "physicians have successfully treated patients infected with B. miyamotoi with a 2-week course of doxycycline"
The CDC stress to take precautions against tick bites.
A.E. Platonov and colleagues published the following study: "Humans Infected with Relapsing Fever Spirochete Borrelia miyamotoi, Russia". They reported 46 cases of B. miyamatoi infection in humans and compared "the frequency and clinical manifestations of this infection with those caused by B. garinii [another Borrelia species found in Europe and Asia] and B. burgdorferi infection." The authors give more information on the symptoms, as they report an "influenza-like illness with fever as high as 39.5°C; relapsing febrile illness occurred in 5 (11%) and erythema migrans in 4 (9%)."
There has been a letter to the editor of the New Enland Journal of Madicine by P.J. Krause and colleagues: "Human Borrelia miyamotoi Infection in the United States". "The identification of B. miyamotoi antibody in 18 of our study patients, including seroconversion associated with symptoms in 3 patients, suggests that B. miyamotoi infection may be prevalent in areas where Lyme disease is endemic in the United States."

Europe already has the problem, that ELISA or IFT tests for B. burgdorferi might be inadequate to detect other Borrelia species than B. burgdorferi sensu strictu. We also have to diagnose B. afzelii or B. garinii and ELISA / IFT test use a common antigene. The immunoblot ("Western blot"), however, is unequivocal. B. miyamotoi is different and warrant a new test, which is under development. Until then it will be difficult to make the diagnosis.
Nobody knows the extent of the problem. Bad ideas include underestimation and panicking. Take precautions against tick bites as other diseases like babesiosis, Tick-borne encephalitis (TBE in Europe), ehrlichiosis, anaplamosis, and more might be passed by ticks. Your physician should think about a two week therapy of doxycycline, if he suspects an infection with Borrelia miyamotoi.


Precautions against tick bites precautions against tick bites

Platonov AE, Karan LS, Kolyasnikova NM, Makhneva NA, Toporkova MG, Maleev VV, et al. Humans infected with relapsing fever spirochete Borrelia miyamotoi, Russia. Emerg Infect Dis [serial on the Internet]. 2011 Oct [date cited].

Letter to the editor of the New Enland Journal of Madicine

The CDC published a study: “Prevalence of Borrelia miyamotoi in Ixodes Ticks in Europe and the United States“. The prevalence differs to a great extent, for instance Konstanz in Germany had a prevalence of 1.8%, New London County showed none, WestchesterCounty 6.8%, and Napa County 15.4%. Borrelia miyamotoi is found in America as well as Eurasia. The risk of infection for humans remains unclear.
“Antibiotics that have been used effectively include doxycycline for uncomplicated B. miyamotoi infection in adults and ceftriaxone or penicillin G for meningoencephalitis.” 2nd link.

Prevalence of Borrelia miyamotoi in Ixodes Ticks in Europe and the United States

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