Subject: PRO/AH/EDR> Tick-borne borreliosis - USA: (South. New Engl., NY) B. miyamotoi
Archive Number: 20130118.1504740
TICK-BORNE BORRELIOSIS - USA: (SOUTHERN NEW ENGLAND, NEW YORK) BORRELIA MIYAMOTOI
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Date: Wed 16 Jan 2013
Source: New Haven Register [edited]
http://nhregister.com/articles/2013/01/16/news/doc50f72407958c0516150206.txt
A new tick-borne infection, similar to Lyme disease, has been found in humans in this region [Connecticut, Massachusetts, Rhode Island, New York] for the 1st time, according to researchers at the Yale schools of Public Health and Medicine. And while its unfamiliarity may result in some misdiagnosis -- the disease, carried by deer ticks, has yet to be given a name -- the good news is that the same treatment used for Lyme disease will cure this infection as well.
NO BULL'S EYE RASH
RELAPSING FEVER
The report, whose primary author is Dr Peter Krause, senior research scientist at the School of Public Health, is published in the 17 Jan 2013 issue of the New England Journal of Medicine. So far 18 patients in southern New England and New York State have been found to have the infection, caused by a bacterium, _Borrelia miyamotoi_, according to a release. It was first found in ticks in 1995 in Japan, then in deer ticks in Connecticut in 2001, Krause said. "The 1st time it was discovered in humans was 2011," when 46 cases of this disease were reported in central Russia, he said.
The discovery is unusual because usually new tick-borne diseases are found when people get sick and then are traced to the insect. "This is the 1st time we have found an infectious organism carried by ticks before we have recognized the disease in humans," said Durland Fish, professor of epidemiology at the School of Public Health and the study's senior author, in the release. "We usually discover new diseases during an epidemic and then try to figure out what is causing it."
While the number of cases so far is small, Krause said there are 30 000 reported cases of Lyme disease in this country each year, and that infection "is probably 7 times as common" as the new disease, which would make more than 4000 cases. But scientists believe the actual number of Lyme disease infections each year is 10 times as high as the reported number.
Symptoms are similar to Lyme -- fever, headache, muscle ache, and fatigue -- but 10 percent of the Russian patients also had relapses of their fever. "They had fever; it was there a few days ... anywhere between a week and a month later they came down with fever again," Krause said. "Some people have had as many as 10 relapses over the course of a year." The Americans discovered with the infection "were treated for suspected Lyme disease so they didn't have relapsing fever ... I think it's likely that some people will have relapsing fever from this," Krause said.
One way to diagnose the new disease is by the 2-part Lyme screening test. "Unfortunately, these patients with _B. miyamotoi_ [infection]... some of them tested positive to that 1st screening test ... but when we did the 2nd test ... that test was negative," Krause said. That result points to the new infection, he said.
"I think we could expect looking ahead that we will find a lot more of these cases," Krause said.
[Byline: Ed Stannard]
Communicated by:
ProMED-mail
[The above news report refers to a recent publication: Krause PJ, Narasimhan S, Wormser GP, et al. Human _Borrelia miyamotoi_ Infection in the United States. N Engl J Med 2013; 368:291-293. In this study, antibody against _Borrelia miyamotoi_ GlpQ protein (an antigen that is nonreactive to _Borrelia burgdorferi_ antibody) was assayed in archived serum samples obtained from 875 patients who were living in areas where Lyme disease is endemic (southern New England and New York State) between 1990 and 2010. 18 of these patients who had been evaluated for Lyme disease had serologic evidence of _B. miyamotoi_ infection; 3 of the 18 patients had serologic evidence of recent _Borrelia miyamotoi_ infection and were not immunocompromised. 5 of the 18 were co-infected, 4 of whom had concomitant Lyme disease based on a typical erythema migrans skin lesion and 1 had concomitant babesiosis.
In the same issue of the New England Journal of Medicine, there is the related article: Gugliotta JL, Goethert HK, Victor P. Berardi VP, Telford SR. Meningoencephalitis from _Borrelia miyamotoi_ in an Immunocompromised Patient. N Engl J Med 2013; 368:240-245. This article describes an immunocompromised elderly patient with a history of tick-exposure who developed progressive dementia and lymphocytic pleocytosis on cerebrospinal fluid (CSF) exam. Spirochetes were visualized in the CSF that differed qualitatively from _Borrelia burgdorferi sensu lato_, the cause of Lyme disease, with respect to their morphologic characteristics and behavior in vitro. PCR assay with the use of primers specific for the _B. miyamotoi_ genogroup and subsequent sequencing and phylogenetic analysis of the 16S rRNA and flagellin genes confirmed that the patient's CSF specimens contained a borrelia within the American clade of the _B. miyamotoi_-like spirochetes. The patient developed of a Jarisch-Herxheimer reaction after receiving antibiotic therapy with ceftriaxone, as do some patients with Lyme disease or relapsing fever. The patient experienced a clinical and microbiologic response to antibiotic treatment; the post-treatment CSF sample was negative for _B. miyamotoi_ on PCR assay.
Lyme disease, also called Lyme borreliosis, is a multisystemic disorder caused by spirochetes belonging to the _Borrelia burgdorferi sensu lato_ complex, a genetically diverse group of spirochetes (http://ijs.sgmjournals.org/content/42/3/378.full.pdf). At least three species of the B. burgdorferi sensu lato complex (_B. afzelii_, _B. garinii_, and _B. burgdorferi sensu stricto_) are known to cause Lyme disease in humans, although _B. burgdorferi sensu stricto_ is the only pathogenic species to cause Lyme disease in North America. It also occurs in Europe, but is less prevalent in most regions than _B. garinii_ or _B. afzelii_, the two major European pathogenic genospecies. Vectors of _B. burgdorferi sensu lato_ complex are hard-bodied _Ixodes_ ticks, and various small and medium-sized mammals and ground-feeding bird species are reservoir-competent hosts. Individual ticks can be infected with more than one genospecies of _B. burgdorferi sensu lato_ complex.
The relapsing-fever group of borrelia, which includes _B. miyamotoi_, is genetically diverse and causes a disease characterized by a high temperature that cyclically remits. _Borrelia hermsii_ is the most frequent cause of tick-borne relapsing fever in the USA. This spirochete is transmitted to humans by the soft tick _Ornithodoros hermsi_, which unlike hard ticks, transmit spirochetes through a brief (less than 30 minutes' duration) and painless nocturnal bite. Humans typically are exposed to these ticks during an overnight stay in rodent-infested dwellings at elevations greater than 2000 feet. In the USA, a majority of the reported cases are from California and Washington. Louse-borne relapsing fever, an illness similar to the tick-borne disease, is caused by _Borrelia recurrentis_, which is transmitted from human to human by the body louse and is spread under conditions of crowding and poor personal hygiene. It remains endemic in parts of central and east Africa and the South American Andes, but has occasionally been imported into the USA.
In the USA, _B. miyamotoi_ has been detected in _Ixodes scapularis_, in Russia and Japan in _Ixodes persulcatus_ (Fukunaga M, Takahashi Y, Tsuruta Y, et al. Genetic and phenotypic analysis of Borrelia miyamotoi sp. nov., isolated from the ixodid tick Ixodes persulcatus, the vector for Lyme disease in Japan. Int J Syst Bacteriol 1995;45:804-810), and in western Europe, _Ixodes ricinus_, the same tick species that spread _B. burgdorferi sensu lato_ complex, the causative agents of Lyme disease.
As described in patients in the USA by Krause et al in the New England Journal of Medicine article above, _B. miyamotoi_ has also caused in patients in Russia an acute febrile illness with fever as high as 39.5 degrees C (103.1 degrees F) and usually does not cause the bull's eye shaped rash that characterizes Lyme disease (Platonov AE, Karan LS, Nadezhda M. Kolyasnikova NM, et al. Humans Infected with Relapsing Fever Spirochete Borrelia miyamotoi, Russia. Emerg Infect Dis 2011;17. Available at:
http://wwwnc.cdc.gov/eid/pdfs/10-1474-ahead_of_print.pdf). In the Gugliotta et al New England Journal of Medicine article referred to above, _B. miyamoto_ apparently has caused progressive dementia without fever in an immunocompromised patient. These recent articles point out that _B. miyamotoi_ may be the cause of an acute febrile illness or meningoencephalitis associated with dementia in regions where _Ixodes_ ticks are endemic.
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