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Deer ticks are well known to spread dangerous bacteria, and in 2009two U.S. States, Minnesota and Wisconsin in particular saw theemergence of a previously unknown species of the tick-borneEhrlichia bacterium that was responsible for mysterious infectionsin the region, previously thought to only exist overseas. Currently designated as Ehrlichia Wisconsin HM543746, the newspecies appears most closely related to E. muris, which untilrecently was thought to be confined to eastern Europe and parts ofAsia. Pritt and colleagues found 98% sequence homology between thetwo species. DNA analysis confirmed that the four individuals, all of whomrecovered, were infected with a still unnamed Ehrlichia speciesdistinct from E. chaffeensis and E. ewingii, the most commonpathogens responsible for ehrlichiosis in the U.S., according toBobbi S. Pritt, MD, of the Mayo Clinic in Rochester, Minnesota. Pritt and colleagues had collected more than 4,000 blood samplesfrom patients with suspected ehrlichiosis or anaplasmosis (aclosely related infection) across the U.S. in 2009, including 1,519from Wisconsin and Minnesota. None of the samples from the twostates were positive for other strains E. chaffeensis or E.ewingii, although 163 contained DNA for Anaplasma phagocytophilum,which causes anaplasmosis. But molecular testing showed that four of the samples wereanomalous, prompting additional investigations that led to the newdiscovery. Patients contributing these samples, two of whom were organtransplant recipients taking immunosuppressants however, hadpresented in the summer and early fall of 2009 with fever , headache , and fatigue; one patient also had nausea and vomiting. Bloodtests showed low levels of lymphocytes in all patients and lowplatelet counts in three. Because the symptoms and the patients' previous travel hadsuggested possible tick-borne infections, they were treated withdoxycycline or ceftazidime and all of them recovered. Organismswere cultured from their blood, with DNA sequences that matchedthose obtained from the clinical specimens. Pritt and colleagues also tested 697 ticks from the two states.They found that 17 (including seven nymphs and nine adults) carriedorganisms with the same sequences as the four patients. Eureka. The most common vector for pathogenic Ehrlichia species in the U.S.is a different tick species, Amblyomma americanum. That species inparticular however, cannot withstand the Upper Midwestern winters-- perhaps one reason that ehrlichiosis is uncommon in the region. The scientists cautioned that their findings did not conclusivelyimplicate it as the vector for the new Ehrlichia species. "Extended investigation and tick surveillance are required tounderstand the distribution of this agent in Wisconsin andMinnesota. Physicians should be aware that a novel pathogenicEhrlichia agent is present in Minnesota and Wisconsin and thatorganism-specific PCR [polymerase chain reaction] and serologictesting can be used to identify the cause of suspected infections." The prevalence of lyme disease (LD) in the northeast and upper mid-west is due to the presence oflarge numbers of the deer tick's preferred hosts, white-footed miceand deer, and their proximity to humans. White-footed mice serve asthe principal carriers on which many larval and juvenile ticks feedand become infected with the LD spirochete. An infected tick canthen transmit infection the next time it feeds on another host,namely...you. Written by Sy Kraft Copyright: Medical News Today Not to be reproduced without permission of Medical News Today Additional References Citations. We are high quality suppliers, our products such as Compressed Air Blow Guns , Electromagnetic Induction Coil for oversee buyer. To know more, please visits Electromagnetic Induction Coil.
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