Evolution of Northeastern and Midwestern Borrelia burgdorferi, United States

The per capita incidence of human Lyme disease in the northeastern United States is more than twice that in the Midwest. However, the prevalence of Borrelia burgdorferi, the bacterium that causes Lyme disease, in the tick vector is nearly identical in the 2 regions. The disparity in human Lyme disease incidence may result from a disparity in the human invasiveness of the bacteria in the Northeast and Midwest caused by fundamentally different evolutionary histories. B. burgdorferi populations in the Northeast and Midwest are geographically isolated, enabling evolutionary divergence in human invasiveness. However, we found that B. burgdorferi populations in the Northeast and Midwest shared a recent common ancestor, which suggests that substantial evolutionary divergence in human invasiveness has not occurred. We propose that differences in either animal ecology or human behavior are the root cause of the differences in human incidence between the 2 regions.     

Prevalence of Borrelia miyamotoi in Ixodes Ticks in Europe and the United States

Borrelia miyamotoi, a relapsing fever-related spirochete transmitted by Ixodes ticks, has been recently shown to be a human pathogen. To characterize the prevalence of this organism in questing Ixodes ticks, we tested 2,754 ticks for a variety of tickborne pathogens by PCR and electrospray-ionization mass spectrometry. Ticks were collected from California, New York, Connecticut, Pennsylvania, and Indiana in the United States and from Germany and the Czech Republic in Europe from 2008 through 2012. In addition, an isolate from Japan was characterized. We found 3 distinct genotypes, 1 for North America, 1 for Europe, and 1 for Japan. We found B. miyamotoi infection in ticks in 16 of the 26 sites surveyed, with infection prevalence as high as 15.4%. These results show the widespread distribution of the pathogen, indicating an exposure risk to humans in areas where Ixodes ticks reside.     

Borrelia species in Ixodes affinis and Ixodes scapularis ticks collected from the coastal plain of North Carolina

Ixodes affinis and I. scapularis are tick species that are widely distributed in the coastal plain region of North Carolina. Both tick species are considered enzootic vectors for spirochetal bacteria of the genus Borrelia and specifically for B. burgdorferi s.s., the pathogen most often attributed as the cause of Lyme disease in the USA. Laboratory testing of individual I. affinis and I. scapularis ticks for the presence of Borrelia DNA was accomplished by PCR, targeting 2 regions of the 16S-23S intergenic spacer. In I. affinis, Borrelia DNA was detected in 63.2% of 155 individual ticks. B. burgdorferi s.s. and B. bissettii were identified by DNA sequencing in 33.5% and 27.9% I. affinis, respectively. Statistical differences were found for sex distribution of Borrelia DNA between I. affinis females (76.8%) and I. affinis males (55.6%) where B. burgdorferi s.s. was more prevalent in females (44.6%) than in males (27.3%). In I. scapularis, 298 individually tested ticks yielded no Borrelia PCR-positive results. This study found a higher incidence of Borrelia spp. in I. affinis collected in coastal North Carolina as compared to previous reports for this tick species in other Southern states, highlighting the potential importance of I. affinis in the maintenance of the enzootic transmission cycle of B. burgdorferi s.l. in North Carolina. The lack of Borrelia DNA in I. scapularis highlights the need for additional studies to better define the transmission cycle for B. burgdorferi s.s. in the southeastern USA and specifically in the state of North Carolina.     

Occurrence of Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii in the Ixodes ricinus ticks from Eastern Slovakia

A total of 2816 unfed adults nymphs of Ixodes ricinus ticks were collected from vegetation in Koice (Eastern Slovakia) from 1994 to 1997. Prevalence of Borrelia burgdorferi s. 1. in I. ricinus ticks, detected by dark field microscopy, varied and depended upon the year and the habitat of the collected ticks. The lowest prevalence was observed in 1994 (4.8%). During 1995 it increased to 17.2% and during the next two years decreased to 15.5% and 14.2%. The rate of infection varied from 2.1 to 23.3% within 10 examined habitats of the Koice area. A different value of relative density of ticks was observed in various habitats. It ranged from 9–212 ticks per collecting hour within one flagged area (600m²) which is 1.5–35.5 ticks per 100m². Eight isolates were obtained from the infected ticks. Electrophoresis and immunoblotting with 6 monoclonal antibodies were used for the identification of Borrelia strains. Three tick isolates were identified as B. burgdorferi s. s. and the other three isolates were found to be B. garinii. One strain reacted as a mixed culture of B. burgdorferi s. s., and B. garinii. The strain originated from the Vihorlat Mountains habitat and was detected by PCR-SSCP as B. burgdorferi s. s. with a small amount of B. afzelii. The obtained results emphasize the epidemiological importance not only of B. garinii and B. afzelii but also of B. burgdorferi s. s. in Central Europe.     

A climate-based model predicts the spatial distribution of the Lyme disease vector Ixodes scapularis in the United States

An understanding of the spatial distribution of the black-legged tick, Ixodes scapularis, is a fundamental component in assessing human risk for Lyme disease in much of the United States. Although a county-level vector distribution map exists for the United States, its accuracy is limited by arbitrary categories of its reported presence. It is unknown whether reported positive areas can support established populations and whether negative areas are suitable for established populations. The steadily increasing range of I. scapularis in the United States suggests that all suitable habitats are not currently occupied. Therefore, we developed a spatially predictive logistic model for I. scapularis in the 48 conterminous states to improve the previous vector distribution map. We used ground-observed environmental data to predict the probability of established I. scapularis populations. The autologistic analysis showed that maximum, minimum, and mean temperatures as well as vapor pressure significantly contribute to population maintenance with an accuracy of 95% (p < 0.0001). A cutoff probability for habitat suitability was assessed by sensitivity analysis and was used to reclassify the previous distribution map. The spatially modeled relationship between I. scapularis presence and large-scale environmental data provides a robust suitability model that reveals essential environmental determinants of habitat suitability, predicts emerging areas of Lyme disease risk, and generates the future pattern of I. scapularis across the United States.     

Predicting the risk of Lyme disease: habitat suitability for Ixodes scapularis in the north central United States

The distribution and abundance of Ixodes scapularis were studied in Wisconsin, northern Illinois, and portions of the Upper Peninsula of Michigan by inspecting small mammals for ticks and by collecting questing ticks at 138 locations in state parks and natural areas. Environmental data were gathered at a local level (i.e., micro and meso levels), and a geographic information system (GIS) was used with several digitized coverages of environmental data to create a habitat profile for each site and a grid map for Wisconsin and Illinois. Results showed that the presence and abundance of I. scapularis varied, even when the host population was adequate. Tick presence was positively associated with deciduous, dry to mesic forests and alfisol-type soils of sandy or loam-sand textures overlying sedimentary rock. Tick absence was associated with grasslands, conifer forests, wet to wet/mesic forests, acidic soils of low fertility and a clay soil texture, and Precambrian bedrock. We performed a discriminant analysis to determine environmental differences between positive and negative tick sites and derived a regression equation to examine the probability of I. scapularis presence per grid. Both analyses indicated that soil order and land cover were the dominant contributors to tick presence. We then constructed a risk map indicating suitable habitats within areas where I. scapularis is already established. The risk map also shows areas of high probability the tick will become established if introduced. Thus, this risk analysis has both explanatory power and predictive capability.     

从桂黔交界地区中华硬蜱中分离到莱姆病螺旋体

目的从桂黔交界地区捕获的蜱中分离莱姆病螺旋体,以探查广西壮族自治区（广西区）和贵州省莱姆病的传播媒介。方法用BSK-Ⅱ培养基从蜱中分离莱姆病螺旋体。用PCR扩增分离菌株的5S～23SrRNA基因间隔区,将PCR扩增产物克隆后测序,通过将测序结果与基因库中莱姆病螺旋体菌株的5S～23SrRNA基因间隔区进行同源性比较和分析,从而鉴定分离株的基因型。结果从捕获的中华硬蜱中分离出1株莱姆病螺旋体（命名为QLT1）。分离株经鉴定为Borrelia valaisiana基因型莱姆病螺旋体。结论中华硬蜱很有可能是广西区和贵州省莱姆病的传播媒介。     

全沟硬蜱在黑龙江小兴安岭莱姆病螺旋体传播中的作用

目的：探讨全沟硬蜱在莱姆病螺旋体传播中的作用。方法：用布旗法在林区草地采蜱，并分类鉴定；用直接荧光抗体法检查蜱类中肠带菌情况，并分离菌株。结果：全沟硬蜱为当地优势蜱种，人群发病与该蜱叮咬率密切相关；该蜱中肠带菌率为４０％，并从１４组（７０只）蜱中分离出２株莱姆病螺旋体；新分离株的单克隆抗体反应与国内分离株Ｍ７相同，而与美国菌株Ｂ３１有区别。结论：当地全沟硬蜱是莱姆病螺旋体的主要生物媒介。     

Doctor-manager relationships in the United States and the United Kingdom

In many developed countries, including the United States and the United Kingdom, the relationships between doctors and hospital managers are strained. The purposes of this article are to examine survey data from the United States and the United Kingdom on doctor-manager relationships and to identify the sources of strain common to both countries as well as those particular to each country's health system. The two countries exhibited many similarities. A very high proportion of respondents from both countries identified external factors-such as governmental budget cuts, pressure from third parties to increase physicians' workload, and the turbulence of the policy environment-as important barriers to improving doctor-manager relationships. Other common sources of strain were concerns over resource availability and the relative power of doctors and managers. Sources of relationship tension particular to each country were also found. Substantial divergence of opinion was expressed with respect to internal factors that affect doctor-manager relationships. Respondents from the United States were more negative than those from the United Kingdom in their ratings of teamwork and communication between doctors and managers, and they were also less likely to have confidence in the medical staff. Respondents from the United Kingdom were more likely to believe that hospital management is driven more by financial than clinical priorities. Managers can implement several strategies to improve doctor-manager relationships, including greater organizational transparency in decision making; more frequent communication between managers and doctors; and more physician involvement in decision making, especially with regard to important resource-related decisions, and in organizational governance.     

Single-step polymerase chain reaction in the detection of Borrelia burgdorferi and the genome species in the Ixodes ricinus tick

The objective of the work to introduce screening PCR into the diagnosis of Borrelia burgdorferi sensu lato in the vector selection of the most suitable primer, derived from chromosomal DNA and detection of different genome species. The sensitivity of primers, described in the literature (LD, 16S, Wk, 5S-23S) was tested by different amounts of DNA strains of borrelias. The most sensitive primer--LD was used for detection of borrelias in the vector. Ticks were collected in municipal parks from 1995-1997. A total of 635 ticks were examined. The positivity of the group differs in individual years: 9.2% in 1995, 3.4% in 1996, and 4.5% in 1997. Adult ticks were markedly more infected than nymphs. Borrelia garinii prevails at the site, Borrelia burgdorferi sensu stricto was not detected so far. Mixed infection with Borrelia garinii/Borrelia afzelii was found in 1997 in one sample (female ticks). PCR is a sensitive and specific method suitable for assessment of the herd immunity of ticks with borrelias. It makes it possible to differentiate with a relatively high sensitivity individual genome species of Borrelia burgdorferi in the vector. Before its use the sensitivity of the reaction must be tested in the presence of tick DNA.     

Distribution and prevalence of Borrelia burgdorferi sensu lato in Ixodes ricinus ticks of canton Ticino (Switzerland)

Free-living Ixodes ricinus ticks were collected from 12 different sites of canton Ticino, south of the Alps (Switzerland). Each tick was examined for the presence of Borrelia burgdorferi sensu lato (sl), the etiologic agent of Lyme borreliosis using direct fluorescent antibody assay, and isolation of the bacteria. Borreliae were characterized by PCR followed by RFLP. The abundance and infection rates of I. ricinus ticks varied greatly between the areas. Two localities were found free of Borrelia. The prevalence of infected ticks ranged from 5 to 19%. Most ticks (96%) were found infected by <50 spirochetes. Three B. burgdorferi sl species were successfully isolated: B. garinii dominated, followed by B. lusitaniae and B. valaisiana. Additionally, a mixed infection with B. garinii and B. valaisiana was observed. The distribution of the various Borrelia species in the different areas was heterogeneous. This is the first report of the presence of B. lusitaniae in I. ricinus in Switzerland.     

Climatic and environmental patterns associated with hantavirus pulmonary syndrome, Four Corners region, United States

To investigate climatic, spatial, temporal, and environmental patterns associated with hantavirus pulmonary syndrome (HPS) cases in the Four Corners region, we collected exposure site data for HPS cases that occurred in 1993 to 1995. Cases clustered seasonally and temporally by biome type and geographic location, and exposure sites were most often found in pinyon-juniper woodlands, grasslands, and Great Basin desert scrub lands, at elevations of 1,800 m to 2,500 m. Environmental factors (e.g., the dramatic increase in precipitation associated with the 1992 to 1993 El Niño) may indirectly increase the risk for Sin Nombre virus exposure and therefore may be of value in designing disease prevention campaigns.     

Borrelia miyamotoi sensu lato Seroreactivity and Seroprevalence in the Northeastern United States

Borrelia miyamotoi sensu lato, a relapsing fever Borrelia sp., is transmitted by the same ticks that transmit B. burgdorferi (the Lyme disease pathogen) and occurs in all Lyme disease�?"endemic areas of the United States. To determine the seroprevalence of IgG against B. miyamotoi sensu lato in the northeastern United States and assess whether serum from B. miyamotoi sensu lato�?"infected persons is reactive to B. burgdorferi antigens, we tested archived serum samples from area residents during 1991�?"2012. Of 639 samples from healthy persons, 25 were positive for B. miyamotoi sensu lato and 60 for B. burgdorferi. Samples from �%^10% of B. miyamotoi sensu lato�?"seropositive persons without a recent history of Lyme disease were seropositive for B. burgdorferi. Our resultsA suggest thatA human B. miyamotoiA sensu latoA infection may be common in southern New England and that B. burgdorferi antibody testing is not an effective surrogate for detecting B. miyamotoi sensu lato infection.     

Air quality and exercise-related health benefits from reduced car travel in the midwestern United States

Background: Automobile exhaust contains precursors to ozone and fine particulate matter (PM ≤ 2.5 µm in aerodynamic diameter; PM_2.5), posing health risks. Dependency on car commuting also reduces physical fitness opportunities.Objective: In this study we sought to quantify benefits from reducing automobile usage for short urban and suburban trips.Methods: We simulated census-tract level changes in hourly pollutant concentrations from the elimination of automobile round trips ≤ 8 km in 11 metropolitan areas in the upper midwestern United States using the Community Multiscale Air Quality (CMAQ) model. Next, we estimated annual changes in health outcomes and monetary costs expected from pollution changes using the U.S. Environmental Protection Agency Benefits Mapping Analysis Program (BenMAP). In addition, we used the World Health Organization Health Economic Assessment Tool (HEAT) to calculate benefits of increased physical activity if 50% of short trips were made by bicycle.Results: We estimate that, by eliminating these short automobile trips, annual average urban PM_2.5 would decline by 0.1 µg/m³ and that summer ozone (O₃) would increase slightly in cities but decline regionally, resulting in net health bene-fits of $4.94 billion/year [95% confidence interval (CI): $0.2 billion, $13.5 billion), with 25% of PM_2.5 and most O₃ bene-fits to populations outside metropolitan areas. Across the study region of approximately 31.3 million people and 37,000 total square miles, mortality would decline by approximately 1,295 deaths/year (95% CI: 912, 1,636) because of improved air quality and increased exercise. Making 50% of short trips by bicycle would yield savings of approximately $3.8 billion/year from avoided mortality and reduced health care costs (95% CI: $2.7 billion, $5.0 billion]. We estimate that the combined benefits of improved air quality and physical fitness would exceed $8 billion/year.Conclusion: Our findings suggest that significant health and economic benefits are possible if bicycling replaces short car trips. Less dependence on automobiles in urban areas would also improve health in downwind rural settings.     

Anaplasma phagocytophilum infection in small mammal hosts of Ixodes ticks, western United States

A total of 2,121 small mammals in California were assessed for Anaplasma phagocytophilum from 2006 through 2008. Odds ratios were >1 for 4 sciurids species and dusky-footed woodrats. High seroprevalence was observed in northern sites. Ten tick species were identified. Heavily infested rodent species included meadow voles, woodrats, deer mice, and redwood chipmunks.     

Antigenic and genomic analysis of a Borrelia burgdorferi sensu stricto strain isolated from Ixodes ricinus ticks in Alto Adige-South Tyrol, Italy

A Borrelia burgdorferi sensu lato strain isolated from Ixodes ricinus ticks in Alto Adige-South Tyrol (Northern Italy) was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole cell proteins, Western immunoblotting analysis (WBA) with polyclonal and monoclonal antibodies, and pulsed-field gel electrophoresis (PFGE). The isolate named BZ6 was identified as belonging to the genospecies B. burgdorferi sensu stricto on the basis of its protein profile and its reactivity with monoclonal and polyclonal antibodies. The PFGE study performed with the two rare-cutting restriction enzymes MluI and SmaI confirmed the SDS-PAGE and WBA characterizations, but showed a genetic diversity between the isolate and two out of the three B. burgdorferi sensu stricto strains used in this study as controls, the American type strain B31 and the locally isolated strain BZ1. No difference in the PFGE patterns between the isolate BZ6 and the Swiss strain IRS was noted. Our findings show the value of PFGE analysis for classifying B. burgdorferi sensu lato isolates and for revealing their genetic diversity, and its usefulness for epidemiological investigations.     

Eating behaviors and health history of rural midlife to older women in the midwestern United States

This study was conducted to examine daily energy, food group, and nutrient intakes of late midlife to older women living in the rural Midwestern United States compared with recommended intakes for the US population, and to describe their physical measures and health history. Random-digit dialing was used to recruit 225 community-dwelling women aged 50 to 69 years from a rural Midwestern area of the United States. Participants completed online food intake and health history surveys. Nearly half of the women had energy intakes in excess of their Estimated Energy Requirement. Mean daily servings of fruits, grains, and dairy products were below target levels identified in the 2000 Dietary Guidelines for Americans. Mean calcium and dietary fiber intakes were below recommended levels, while percent calories from fat (39.0%+/-6.8%) were well above recommendations. Eighty percent were overweight or obese and 76% were prehypertensive or hypertensive, yet only 33.5% indicated their health care provider had discussed dietary factors with them in the previous year. Late midlife and older rural Midwestern women, aged 50 to 69 years, need more guidance than they currently receive to learn how to make changes to meet dietary recommendations, particularly with a focus on establishing a more healthful dietary pattern that will be suitable for their older years.     

Comparison in the immunological properties of Borrelia burgdorferi isolates from Ixodes ricinus derived from three endemic areas in Switzerland.

Borrelia burgdorferi isolates were obtained from Ixodes ricinus from three sites in Switzerland. They were examined by SDS-PAGE and immunoblotting. The phenotypes, in respect of three outer surface proteins (Osp), differed between the sites of collection. In site 1, most isolates had an OspA of 31 kDa and an OspB of 34 kDa; in site 2, isolates presenting an OspA of 33 kDa dominated and in site 3, the isolates with an OspA of 32 kDa and an OspB of 35 kDa were most frequent. This distribution differed significantly. About half of the isolates from sites 1 and 3 reacted with anti-OspA monoclonal antibody H5332 compared to 29% from site 2. Site 1 isolates reacted significantly more frequently (81%) with another anti-OspA monoclonal antibody LA-31 than isolates from site 3 (P < 0.0001). These findings have implications for the epidemiology of Lyme borreliosis, for the further development of serodiagnostic reagents and for the development of a vaccine.