Borrelia mayonii sp. nov., a member of the Borrelia burgdorferi sensu lato complex, detected in patients and ticks in the upper midwestern United States.

Lyme borreliosis (LB) is a multisystem disease caused by spirochetes in the Borrelia burgdorferisensu lato (Bbsl) genospecies complex. We previously described a novel Bbsl genospecies (type strain MN14-1420T) that causes LB among patients with exposures to ticks in the upper midwestern USA. Patients infected with the novel Bbsl genospecies demonstrated higher levels of spirochetemia and somewhat differing clinical symptoms as compared with those infected with other Bbsl genospecies. The organism was detected from human specimens using PCR, microscopy, serology and culture. The taxonomic status was determined using an eight-housekeeping-gene (uvrA, rplB, recG, pyrG, pepX, clpX, clpA and nifS) multi-locus sequence analysis (MLSA) and comparison of 16S rRNA gene, flaB, rrf-rrl, ospC and oppA2 nucleotide sequences. Using a system threshold of 98.3 % similarity for delineation of Bbsl genospecies by MLSA, we demonstrated that the novel species is a member of the Bbsl genospecies complex, most closely related to B. burgdorferisensu stricto (94.7-94.9 % similarity). This same species was identified in Ixodes scapularis ticks collected in Minnesota and Wisconsin. This novel species, Borrelia mayonii sp. nov, is formally described here. The type strain, MN14-1420, is available through the Deutsche Sammlung von Mikroorganismen und Zelkulturen GmbH (DSM 102811) and the American Type Culture Collection (ATCC BAA-2743).

Identification of a novel pathogenic Borrelia species causing Lyme borreliosis with unusually high spirochaetaemia: a descriptive study.

BACKGROUND: Lyme borreliosis is the most common tick-borne disease in the northern hemisphere. It is a multisystem disease caused by Borrelia burgdorferi sensu lato genospecies and characterised by tissue localisation and low spirochaetaemia. In this study we aimed to describe a novel Borrelia species causing Lyme borreliosis in the USA. METHODS: At the Mayo clinic, from 2003 to 2014, we tested routine clinical diagnostic specimens from patients in the USA with PCR targeting the oppA1 gene of B burgdorferi sensu lato. We identified positive specimens with an atypical PCR result (melting temperature outside of the expected range) by sequencing, microscopy, or culture. We collected Ixodes scapularis ticks from regions of suspected patient tick exposure and tested them by oppA1 PCR. FINDINGS: 100 545 specimens were submitted by physicians for routine PCR from Jan 1, 2003 to Sept 30, 2014. From these samples, six clinical specimens (five blood, one synovial fluid) yielded an atypical oppA1 PCR product, but no atypical results were detected before 2012. Five of the six patients with atypical PCR results had presented with fever, four had diffuse or focal rash, three had symptoms suggestive of neurological inclusion, and two were admitted to hospital. The sixth patient presented with knee pain and swelling. Motile spirochaetes were seen in blood samples from one patient and cultured from blood samples from two patients. Among the five blood specimens, the median oppA1 copy number was 180 times higher than that in 13 specimens that tested positive for B burgdorferi sensu stricto during the same time period. Multigene sequencing identified the spirochaete as a novel B burgdorferi sensu lato genospecies. This same genospecies was detected in ticks collected at a probable patient exposure site. INTERPRETATION: We describe a new pathogenic Borrelia burgdorferi sensu lato genospecies (candidatus Borrelia mayonii) in the upper midwestern USA, which causes Lyme borreliosis with unusually high spirochaetaemia. Clinicians should be aware of this new B burgdorferi sensu lato genospecies, its distinct clinical features, and the usefulness of oppA1 PCR for diagnosis. FUNDING: US Centers for Disease Control and Prevention Epidemiology and Laboratory Capacity for Infectious Diseases (ELC) Cooperative Agreement and Mayo Clinic Small Grant programme.

Human Infection with Ehrlichia muris-like Pathogen, United States, 2007-2013(1).

An Ehrlichia muris-like (EML) pathogen was detected among 4 patients in Minnesota and Wisconsin during 2009. We characterized additional cases clinically and epidemiologically. During 2004-2013, blood samples from 75,077 patients from all 50 United States were tested by PCR from the groEL gene for Ehrlichia spp. and Anaplasma phagocytophilum. During 2007-2013, samples from 69 (0.1%) patients were positive for the EML pathogen; patients were from 5 states: Indiana (1), Michigan (1), Minnesota (33), North Dakota (3), and Wisconsin (31). Most (64%) patients were male; median age was 63 (range 15-94) years; and all 69 patients reported likely tick exposure in Minnesota or Wisconsin. Fever, malaise, thrombocytopenia, and lymphopenia were the most common symptoms. Sixteen (23%) patients were hospitalized (median 4 days); all recovered, and 96% received doxycycline. Infection with the EML pathogen should be considered for persons reporting tick exposure in Minnesota or Wisconsin.

Epidemiology of West Nile virus in the highly epidemic state of North Dakota, 2002-2007.

OBJECTIVES: West Nile virus (WNV) continues to cause seasonal epidemics of neuroinvasive disease and febrile illness, which have been most dramatic in the central plains states. We studied the epidemiology of WNV disease in North Dakota (ND), a highly epidemic state, six years following its first appearance in the state. METHODS: We analyzed information from cases of WNV disease reported to the ND Department of Health during August 2002 through December 2007. RESULTS: A total of 1246 cases of WNV disease were reported in ND; 183 cases experienced neuroinvasive disease, including meningitis, encephalitis, or acute flaccid paralysis. Risk factors associated with developing neuroinvasive disease rather than West Nile fever included older age, male gender, and residence in a rural area. Annual cumulative incidence of neuroinvasive disease in ND ranged from 0.3 per 100,000 population to 14.6 per 100,000 population. CONCLUSIONS: Annual cumulative incidence rates of West Nile neuroinvasive disease suggest that this region offers favorable conditions for its continued enzootic transmission, which highlights the need for improved targeted prevention measures, particularly for rural areas of the state.