Epidemic Spread of Lyme Borreliosis, Northeastern United States

Host specialization is a key issue in infectious disease research because patterns of cross-species transmission affect parasite dispersal

State-building, war and violence : evidence from Latin America

In European history, war has played a major role in state‐building and the state monopoly on violence. But war is a very specific form of organized political violence, and it is decreasing on a global scale. Other patterns of armed violence now dominate, ones that seem to undermine state‐building, thus preventing the replication of European experiences. As a consequence, the main focus of the current state‐building debate is on fragility and a lack of violence control inside these states. Evidence from Latin American history shows that the specific patterns of the termination of both war and violence are more important than the specific patterns of their organization. Hence these patterns can be conceptualized as a critical juncture for state‐building. While military victories in war, the subordination of competing armed actors and the prosecution of perpetrators are conducive for state‐building, negotiated settlements, coexistence, and impunity produce instability due to competing patterns of authority, legitimacy, and social cohesion

Fine-Scale Phylogeographic Structure of Borrelia lusitaniae Revealed by Multilocus Sequence Typing

Borrelia lusitaniae is an Old World species of the Lyme borreliosis (LB) group of tick-borne spirochetes and prevails mainly in countries around the Mediterranean Basin. Lizards of the family Lacertidae have been identified as reservoir hosts of B. lusitaniae. These reptiles are highly structured geographically, indicating limited migration. In order to examine whether host geographic structure shapes the evolution and epidemiology of B. lusitaniae, we analyzed the phylogeographic population structure of this tick-borne bacterium using a recently developed multilocus sequence typing (MLST) scheme based on chromosomal housekeeping genes. A total of 2,099 questing nymphal and adult Ixodes ricinus ticks were collected in two climatically different regions of Portugal, being ∼130 km apart. All ticks were screened for spirochetes by direct PCR. Attempts to isolate strains yielded 16 cultures of B. lusitaniae in total. Uncontaminated cultures as well as infected ticks were included in this study. The results using MLST show that the regional B. lusitaniae populations constitute genetically distinct populations. In contrast, no clear phylogeographic signals were detected in sequences of the commonly used molecular markers ospA and ospC. The pronounced population structure of B. lusitaniae over a short geographic distance as captured by MLST of the housekeeping genes suggests that the migration rates of B. lusitaniae are rather low, most likely because the distribution of mediterranean lizard populations is highly parapatric. The study underlines the importance of vertebrate hosts in the geographic spread of tick-borne microparasites

Bacteriolytic Activity of Selected Vertebrate Sera for \u3ci\u3eBorrelia burgdorferi\u3c/i\u3e Sensu Stricto and \u3ci\u3eBorrelia bissettii\u3c/i\u3e

An in vitro assay to evaluate the bacteriolytic activity of the complement pathway was applied to 2 strains of Borrelia bissettii, CO501 and DN127, and compared with that of B. burgdorferi sensu stricto B31. Sera from mule deer ( Odocoileus hemionus) and the Western Fence lizard ( Sceloporus occidentalis) were completely borreliacidal for B. burgdorferi and for both strains of B. bissettii. Serum from Bobwhite quail ( Colinus virginianus) was nonlytic for B. burgdorferi and partially lytic for B. bissettii strains, CO-501 and DN127. Serum from a New Zealand White rabbit ( Oryctolagus cuniculus) was partially lytic for all 3 strains of Borrelia, whereas serum from white-footed mice ( Peromyscus leucopus) were nonlytic for all 3 Borrelia strains. The spectrum of complement sensitivity of B. bissettii appears to be similar to that of European B. afzelii in that tested rodent serum is not lytic to these 2 genospecies. Interestingly, both B. bissettii and B. afzelii have been found to be closely associated with rodents. Complement sensitivity demonstrated in these experiments may suggest and possibly predict specific reservoir–host associations

Association of\u3ci\u3e Borrelia garinii\u3c/i\u3e and \u3ci\u3e B. valaisiana\u3c/i\u3e with Songbirds in Slovakia

In Europe, 6 of the 11 genospecies of Borrelia burgdorferi sensu lato are prevalent in questing Ixodes ricinus ticks. In most parts of Central Europe, B. afzelii, B. garinii, and B. valaisiana are the most frequent species, whereas B. burgdorferi sensu stricto, B. bissettii, and B. lusitaniae are rare. Previously, it has been shown that B. afzelii is associated with European rodents. Therefore, the aim of this study was to identify reservoir hosts of B. garinii and B. valaisiana in Slovakia. Songbirds were captured in a woodland near Bratislava and investigated for engorged ticks. Questing I. ricinus ticks were collected in the same region. Both tick pools were analyzed for spirochete infections by PCR, followed by DNA-DNA hybridization and, for a subsample, by nucleotide sequencing. Three of the 17 captured songbird species were infested with spirochete-infected ticks. Spirochetes in ticks that had fed on birds were genotyped as B. garinii and B. valaisiana, whereas questing ticks were infected with B. afzelii, B. garinii, and B. valaisiana. Furthermore, identical ospA alleles of B. garinii were found in ticks that had fed on the birds and in questing ticks. The data show that songbirds are reservoir hosts of B. garinii and B. valaisiana but not of B. afzelii. This and previous studies confirm that B. burgdorferi sensu lato is host associated and that this bacterial species complex contains different ecotypes

Plasmid profile analysis of Portuguese Borrelia lusitaniae strains

Plasmid profilesof2Portuguese Borrelia lusitaniae strains, oneisolatedfromahumanpatientandthe other onefroman Ixodes ricinus tick, wereobtainedbypulsed-fieldgelelectrophoresistoevaluatethe plasmid diversityineachstrain.Overall,amaximumof6plasmidsweredetectedthatrangedfrom 19 kbto76kb,revealingcompletelydifferentplasmidprofilesfromthosepreviouslydescribedforother genospecies of B. burgdorferi sensu lato,thecausativeagentsofLymeborreliosis.Theplasmidlocationof the ospA gene wasinvestigatedbyhybridization,allowingitsallocationtotheplasmidof70kbinstead of the54kblinearplasmiddescribedfor B. burgdorferi sensu strictostrains