scholarly journals Complex Population Structure of Borrelia burgdorferi in Southeastern and South Central Canada as Revealed by Phylogeographic Analysis

2014 ◽  
Vol 81 (4) ◽  
pp. 1309-1318 ◽  
Author(s):  
S. Mechai ◽  
G. Margos ◽  
E. J. Feil ◽  
L. R. Lindsay ◽  
N. H. Ogden

ABSTRACTLyme disease, caused by the bacteriumBorrelia burgdorferisensu stricto, is an emerging zoonotic disease in Canada and is vectored by the blacklegged tick,Ixodes scapularis. Here we used Bayesian analyses of sequence types (STs), determined by multilocus sequence typing (MLST), to investigate the phylogeography ofB. burgdorferipopulations in southern Canada and the United States by analyzing MLST data from 564B. burgdorferi-positive samples collected during surveillance. A total of 107 Canadian samples from field sites were characterized as part of this study, and these data were combined with existing MLST data for samples from the United States and Canada. Only 17% of STs were common between both countries, while 49% occurred only in the United States, and 34% occurred only in Canada. However, STs in southeastern Ontario and southwestern Quebec were typically identical to those in the northeastern United States, suggesting a recent introduction into this region from the United States. In contrast, STs in other locations in Canada (the Maritimes; Long Point, Ontario; and southeastern Manitoba) were frequently unique to those locations but were putative descendants of STs previously found in the United States. The picture in Canada is consistent with relatively recent introductions from multiple refugial populations in the United States. These data thus point to a geographic pattern of populations ofB. burgdorferiin North America that may be more complex than simply comprising northeastern, midwestern, and Californian groups. We speculate that this reflects the complex ecology and spatial distribution of key reservoir hosts.

2017 ◽  
Vol 5 (28) ◽  
Author(s):  
Gabriele Margos ◽  
Sabrina Hepner ◽  
Christoph Mang ◽  
Andreas Sing ◽  
Bernhard Liebl ◽  
...  

ABSTRACT Borrelia burgdorferi sensu stricto is a causative agent of human Lyme borreliosis in the United States and Europe. We report here the completed genome sequences of strain B31 isolated from a tick in the United States and two closely related strains from Europe, PAli and PAbe, which were isolated from patients with erythema migrans and neuroborreliosis, respectively.


2009 ◽  
Vol 78 (1) ◽  
pp. 138-144 ◽  
Author(s):  
Sarojini Adusumilli ◽  
Carmen J. Booth ◽  
Juan Anguita ◽  
Erol Fikrig

ABSTRACT Lyme disease is the most common tick-borne illness in the United States. In this paper we explore the contribution of Ixodes scapularis ticks to the pathogenicity of Borrelia burgdorferi in mice. Previously we demonstrated that an isolate of B. burgdorferi sensu stricto (designated N40), passaged 75 times in vitro (N40-75), was infectious but was no longer able to cause arthritis and carditis in C3H mice. We now show that N40-75 spirochetes can readily colonize I. scapularis and multiply during tick engorgement. Remarkably, tick-transmitted N40-75 spirochetes cause disease in mice. N40-75 spirochetes isolated from these animals also retained their pathogenicity when subsequently administered to mice via syringe inoculation. Array analysis revealed that several genes associated with virulence, including bba25, bba65, bba66, bbj09, and bbk32, had higher expression levels in the tick-passaged N40-75 spirochete. These data suggest that transmission of a high-passage attenuated isolate of B. burgdorferi by the arthropod vector results in the generation of spirochetes that have enhanced pathogenesis in mice.


2011 ◽  
Vol 77 (10) ◽  
pp. 3244-3254 ◽  
Author(s):  
N. H. Ogden ◽  
G. Margos ◽  
D. M. Aanensen ◽  
M. A. Drebot ◽  
E. J. Feil ◽  
...  

ABSTRACTThe genetic diversity ofBorrelia burgdorferisensu stricto, the agent of Lyme disease in North America, has consequences for the performance of serological diagnostic tests and disease severity. To investigateB. burgdorferidiversity in Canada, where Lyme disease is emerging, bacterial DNA in 309 infected adultIxodes scapularisticks collected in surveillance was characterized by multilocus sequence typing (MLST) and analysis of outer surface protein C gene (ospC) alleles. Six ticks carriedBorrelia miyamotoi, and one tick carried the novel speciesBorrelia kurtenbachii. 142 ticks carriedB. burgdorferisequence types (STs) previously described from the United States. Fifty-eight ticks carriedB. burgdorferiof 1 of 19 novel or undescribed STs, which were single-, double-, or triple-locus variants of STs first described in the United States. Clonal complexes with founder STs from the United States were identified. SeventeenospCalleles were identified in 309B. burgdorferi-infected ticks. Positive and negative associations in the occurrence of different alleles in the same tick supported a hypothesis of multiple-niche polymorphism forB. burgdorferiin North America. Geographic analysis of STs andospCalleles were consistent with south-to-north dispersion of infected ticks from U.S. sources on migratory birds. These observations suggest that the genetic diversity ofB. burgdorferiin eastern and central Canada corresponds to that in the United States, but there was evidence for founder events skewing the diversity in emerging tick populations. Further studies are needed to investigate the significance of these observations for the performance of diagnostic tests and clinical presentation of Lyme disease in Canada.


Author(s):  
T E Zembsch ◽  
X Lee ◽  
G M Bron ◽  
L C Bartholomay ◽  
S M Paskewitz

Abstract Borrelia burgdorferi, the spirochete that causes Lyme disease, is endemic and widespread in Wisconsin. Research in the northeastern United States has revealed a positive association between Babesia microti, the main pathogen that causes babesiosis in humans, and Bo. burgdorferi in humans and in ticks. This study was conducted to examine associations between the disease agents in the Upper midwestern United States. Ixodes scapularis Say nymphs (N = 2,858) collected between 2015 and 2017 from nine locations in Wisconsin were tested for Babesia spp. and Borrelia spp. using real-time PCR. Two species of Babesia were detected; Ba. microti and Babesia odocoilei (a parasite of members of the family Cervidae). Prevalence of infection at the nine locations ranged from 0 to 13% for Ba. microti, 11 to 31% for Bo. burgdorferi sensu stricto, and 5.7 to 26% for Ba. odocoilei. Coinfection of nymphs with Bo. burgdorferi and Ba. odocoilei was detected in eight of the nine locations and significant positive associations were observed in two of the eight locations. The prevalence of nymphal coinfection with both and Bo. burgdorferi and Ba. microti ranged from 0.81 to 6.5%. These two pathogens were significantly positively associated in one of the five locations where both pathogens were detected. In the other four locations, the observed prevalence of coinfection was higher than expected in all but one site-year. Clinics and healthcare providers should be aware of the association between Ba. microti and Bo. burgdorferi pathogens when treating patients who report tick bites.


2012 ◽  
Vol 19 (4) ◽  
pp. 527-535 ◽  
Author(s):  
Bettina Wagner ◽  
Heather Freer ◽  
Alicia Rollins ◽  
David Garcia-Tapia ◽  
Hollis N. Erb ◽  
...  

ABSTRACTLyme disease in the United States is caused byBorrelia burgdorferisensu stricto, which is transmitted to mammals by infected ticks.Borreliaspirochetes differentially express immunogenic outer surface proteins (Osp). Our aim was to evaluate antibody responses to Osp antigens to aid the diagnosis of early infection and the management of Lyme disease. We analyzed antibody responses during the first 3 months after the experimental infection of dogs using a novel multiplex assay. Results were compared to those obtained with two commercial assays detecting C6 antigen. Multiplex analysis identified antibodies to OspC and C6 as early as 3 weeks postinfection (p.i.) and those to OspF by 5 weeks p.i. Antibodies to C6 and OspF increased throughout the study, while antibodies to OspC peaked between 7 and 11 weeks p.i. and declined thereafter. A short-term antibody response to OspA was observed in 3/8 experimentally infected dogs on day 21 p.i. Quant C6 enzyme-linked immunosorbent assay (ELISA) results matched multiplex results during the first 7 weeks p.i.; however, antibody levels subsequently declined by up to 29%. Immune responses then were analyzed in sera from 125 client-owned dogs and revealed high agreement between antibodies to OspF and C6 as robust markers for infection. Results from canine patient sera supported that OspC is an early infection marker and antibodies to OspC decline over time. The onset and decline of antibody responses toB. burgdorferiOsp antigens and C6 reflect their differential expression during infection. They provide valuable tools to determine the stage of infection, treatment outcomes, and vaccination status in dogs.


2014 ◽  
Vol 58 (8) ◽  
pp. 4923-4927 ◽  
Author(s):  
Rodrigo E. Mendes ◽  
Donald Biek ◽  
Ian A. Critchley ◽  
David J. Farrell ◽  
Helio S. Sader ◽  
...  

ABSTRACTTotals of 8.7% (103/1,190) and 21.0% (249/1,190) of theStreptococcus pneumoniaeisolates recovered from specimens collected in the United States during the 2011-2012 AWARE (AssessingWorldwideAntimicrobialResistanceEvaluation) Surveillance Program were ceftriaxone nonsusceptible according to the CLSI (≤1 μg/ml for susceptible) and EUCAST (≤0.5 μg/ml for susceptible) criteria, respectively. Decreased susceptibility to ceftriaxone (MIC, 1 μg/ml) was frequently observed among serotypes 19A (51.4%; 128/249) and 35B (29.7%; 74/249), which were most often observed in the East South Central and South Atlantic U.S. Census regions. Ceftaroline (MIC50/90, 0.12/0.25 μg/ml) remained active (≥96.8% susceptible) when tested against these less susceptible isolates.


2016 ◽  
Vol 54 (5) ◽  
pp. 1191-1196 ◽  
Author(s):  
Elitza S. Theel

Lyme disease prevails as the most commonly transmitted tick-borne infection in the United States, and serologic evaluation for antibodies toBorrelia burgdorferiremains the recommended modality for diagnosis. This review presents a brief historical perspective on the evolution of serologic assays for Lyme disease and provides a summary of the performance characteristics for the currently recommended two-tiered testing algorithm (TTTA). Additionally, a recently proposed alternative to the traditional TTTA is discussed, and novel methodologies, including immuno-PCR and metabolic profiling for Lyme disease, are outlined.


2015 ◽  
Vol 81 (21) ◽  
pp. 7350-7359 ◽  
Author(s):  
N. H. Ogden ◽  
E. J. Feil ◽  
P. A. Leighton ◽  
L. R. Lindsay ◽  
G. Margos ◽  
...  

ABSTRACTIn North America, Lyme disease (LD) is a tick-borne zoonosis caused by the spirochete bacteriumBorrelia burgdorferisensu stricto, which is maintained by wildlife. Tick vectors and bacteria are currently spreading into Canada and causing increasing numbers of cases of LD in humans and raising a pressing need for public health responses. There is no vaccine, and LD prevention depends on knowing who is at risk and informing them how to protect themselves from infection. Recently, it was found in the United States that some strains ofB. burgdorferisensu strictocause severe disease, whereas others cause mild, self-limiting disease. While many strains occurring in the United States also occur in Canada, strains in some parts of Canada are different from those in the United States. We therefore recognize a need to identify which strains specific to Canada can cause severe disease and to characterize their geographic distribution to determine which Canadians are particularly at risk. In this review, we summarize the history of emergence of LD in North America, our current knowledge ofB. burgdorferisensu strictodiversity, its intriguing origins in the ecology and evolution of the bacterium, and its importance for the epidemiology and clinical and laboratory diagnosis of LD. We propose methods for investigating associations betweenB. burgdorferisensu strictodiversity, ecology, and pathogenicity and for developing predictive tools to guide public health interventions. We also highlight the emergence ofB. burgdorferisensu strictoin Canada as a unique opportunity for exploring the evolutionary aspects of tick-borne pathogen emergence.


2014 ◽  
Vol 80 (12) ◽  
pp. 3632-3644 ◽  
Author(s):  
Sangmi Lee ◽  
Todd J. Ward ◽  
Lewis M. Graves ◽  
Cheryl L. Tarr ◽  
Robin M. Siletzky ◽  
...  

ABSTRACTListeria monocytogenescan cause severe food-borne disease (listeriosis). Numerous outbreaks have involved three serotype 4b epidemic clones (ECs): ECI, ECII, and ECIa. However, little is known about the population structure ofL. monocytogenesserotype 4b from sporadic listeriosis in the United States, even though most cases of human listeriosis are in fact sporadic. Here we analyzed 136 serotype 4b isolates from sporadic cases in the United States, 2003 to 2008, utilizing multiple tools including multilocus genotyping, pulsed-field gel electrophoresis, and sequence analysis of theinlABlocus. ECI, ECII, and ECIa were frequently encountered (32, 17, and 7%, respectively). However, annually 30 to 68% of isolates were outside these ECs, and several novel clonal groups were identified. An estimated 33 and 17% of the isolates, mostly among the ECs, were resistant to cadmium and arsenic, respectively, but resistance to benzalkonium chloride was uncommon (3%) among the sporadic isolates. The frequency of clonal groups fluctuated within the 6-year study period, without consistent trends. However, on several occasions, temporal clusters of isolates with indistinguishable genotypes were detected, suggesting the possibility of hidden multistate outbreaks. Our analysis suggests a complex population structure of serotype 4bL. monocytogenesfrom sporadic disease, with important contributions by ECs and several novel clonal groups. Continuous monitoring will be needed to assess long-term trends in clonality patterns and population structure ofL. monocytogenesfrom sporadic listeriosis.


Genetics ◽  
2002 ◽  
Vol 160 (3) ◽  
pp. 833-849
Author(s):  
Wei-Gang Qiu ◽  
Daniel E Dykhuizen ◽  
Michael S Acosta ◽  
Benjamin J Luft

Abstract Over 80% of reported cases of Lyme disease in the United States occur in coastal regions of northeastern and mid-Atlantic states. The genetic structure of the Lyme disease spirochete (Borrelia burgdorferi) and its main tick vector (Ixodes scapularis) was studied concurrently and comparatively by sampling natural populations of I. scapularis ticks along the East Coast from 1996 to 1998. Borrelia is genetically highly diverse at the outer surface protein ospC. Since Borrelia is highly clonal, the ospC alleles can be used to define clones. A newly designed reverse line blotting (RLB) assay shows that up to 10 Borrelia clones can infect a single tick. The clone frequencies in Borrelia populations are the same across the Northeast. On the other hand, I. scapularis populations show strong regional divergence (among northeastern, mid-Atlantic, and southern states) as well as local differentiation. The high genetic diversity within Borrelia populations and the disparity in the genetic structure between Borrelia and its tick vector are likely consequences of strong balancing selection on local Borrelia clones. Demographically, both Borrelia and I. scapularis populations in the Northeast show the characteristics of a species that has recently expanded from a population bottleneck. Major geological and ecological events, such as the last glacial maximum (18,000 years ago) and the modern-day expansion of tick habitats, are likely causes of the observed “founder effects” for the two organisms in the Northeast. We therefore conclude that the genetic structure of B. burgdorferi has been intimately shaped by the natural history of its main vector, the northern lineage of I. scapularis ticks.


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