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.     

Genetic determination of biological age in the Mennonites of the Midwestern United States

Numerous studies have shown that longevity is moderately heritable in human populations. Longevity, however, contains limited information on functional status, since individuals may exhibit differential survival patterns. In this study, we employed a stepwise multiple regression approach to estimate biological aging in a Mennonite population, using chronological age as a dependent variable and various predictors of chronological age including subphenotypes related to diabetes, coronary heart disease, hypertension, renal function, and markers of functional ability. The residual (the difference between chronological and predicted ages) is considered a marker of biological age. In fact, two different data sets were used to obtain residuals due to the availability of data. In each analysis, chronological age was regressed on predictor variables in a stepwise manner, retaining the variables significant at the 5% level. The first analysis (N=729) included 6 significant predictors (R(2)=44.3%): glucose, blood urea nitrogen (BUN), cholesterol, albumin, systolic blood pressure (SBP), and ln potassium, and the second analysis (N=232) included 9 significant predictors (R(2)=71.5%): BUN, albumin, SBP, low-density lipoprotein cholesterol, forced expiratory volume in 1 sec (FEV1), grip strength, trunk flexibility, reaction time, and FEV1xsex. Using a variance components approach, we found that the data set-specific residuals were significantly heritable (h(2)+/-SE): first analysis=0.265+/-0.106, and second analysis=0.469+/-0.180. The residuals from the second data set appear to be more informative for biological aging, perhaps due to the inclusion of functional ability-related phenotypes in addition to the blood chemistry variables. In summary, we have shown that markers of biological aging in Mennonites are under substantial additive genetic influences.     

Self-reported occupational injuries among industrial beef slaughterhouse workers in the Midwestern United States

Although workers in meatpacking facilities in the U.S. experience high rates of occupational injury, their injury experiences have received limited research attention. Prior research indicates underreporting in injury rates in this industry as well significant variation in injury rates among facilities. To add detail to the rates and circumstances surrounding occupational injury among meatpacking workers, we conducted a cross-sectional study of workers employed at an industrial beefpacking plant in Nebraska (n = 137) and interviewed workers about recent injury experiences. We assessed frequency, cause and nature of self-reported injury. We estimated annual incidence rates of self-reported injuries using the OSHA formula and compared these rates to industry-wide data. We also evaluated psychological distress in this workforce as measured by the Kessler-6 scale to assess whether distress was associated with recent occupational injury. In this study, 15.1% of workers experienced occupational injuries that required time off work, job transfer, or restriction during the past three months. The estimated annual incidence rate was 15.2 injuries per 100 full-time workers for these injuries at this plant. Rushing was identified as the cause of nearly 50% of injuries, and repetitive work as the cause of an additional 20% of injuries. Use of metal mesh sleeves (POR: 0.10 (p = 0.008)) and metal mesh gloves (POR: 0.41 (p = 0.05) were associated with reduced risk of injury. Use of a carbon steel for knife sharpening (POR: 5.2 (p = 0.02)) was associated with elevated risk of moderate and severe injury. There were no associations between self-reported occupational injury and overall measures of psychological distress. Self-reported incidence rate of severe injury in this plant was more than twice official industry estimates. Worker self-reports may illustrate key areas for injury prevention.     

A Data Driven Approach for Prioritizing COVID-19 Vaccinations in the Midwestern United States

Considering the potential for widespread adoption of social vulnerability indices (SVI) to prioritize COVID-19 vaccinations, there is a need to carefully assess them, particularly for correspondence with outcomes (such as loss of life) in the context of the COVID-19 pandemic. The University of Illinois at Chicago School of Public Health Public Health GIS team developed a methodology for assessing and deriving vulnerability indices based on the premise that these indices are, in the final analysis, classifiers. Application of this methodology to several Midwestern states with a commonly used SVI indicates that by using only the SVI rankings there is a risk of assigning a high priority to locations with the lowest mortality rates and low priority to locations with the highest mortality rates. Based on the findings, we propose using a two-dimensional approach to rationalize the distribution of vaccinations. This approach has the potential to account for areas with high vulnerability characteristics as well as to incorporate the areas that were hard hit by the pandemic.     

Rural Health Research: Factors Affecting Use of Chiropractic Services in Seven Midwestern States of the United States

Although chiropractic is used by approximately 10 percent of the U.S. population, predictors of its use have not been definitively described. Previous studies have suggested that chiropractic users differ from nonusers in a number of sociodemographic characteristics, but their findings are inconsistent, perhaps because of differences in populations sampled and dates of data collection, most of which are prior to 1990. Regional studies have been conducted in rural areas based on the premise that rural residents are more likely than non-rural residents to use chiropractice; however, this premise has not been definitively documented. The purpose of this study was to provide clarification of these sociodemographic predictors of chiropractic use in Illinois, Iowa, Minnesota, Missouri, Nebraska, South Dakota and Wisconsin by characterizing chiropractic users and nonusers in terms of sociodemographics, including rural or non-rural residence, and presence of low back pain. Data from 1,511 respondents to a 1994 population-based survey, conducted by the University of Iowa Social Science Institute, were analyzed. Unconditional logistic regression was used to derive odds ratios and 95 percent confidence intervals for univariate and multiple regression models. Overall, 15.1 percent of respondents had used chiropractic within the last year, most often for low back pain (57 percent). Chiropractic use was less likely in African Americans, Hispanics and Asians than whites, less likely by non-rural than rural residents, and less likely in Catholics than Protestants in states other than Iowa and South Dakota. Overall, 42.7 percent of workers with low back pain reported using chiropractic, and use increased with age but remained significantly related to race, rural or non-rural residence, state of residence and religious preference. Race, rural or non-rural residence, state of residence and religious preference, independently of low back pain, affect use of chiropractice in seven Midwestern states.     

Predicting Chronic Fine and Coarse Particulate Exposures Using Spatiotemporal Models for the Northeastern and Midwestern United States

Background

Chronic epidemiologic studies of particulate matter (PM) are limited by the lack of monitoring data, relying instead on citywide ambient concentrations to estimate exposures. This method ignores within-city spatial gradients and restricts studies to areas with nearby monitoring data. This lack of data is particularly restrictive for fine particles (PM with aerodynamic diameter < 2.5 μm; PM_2.5) and coarse particles (PM with aerodynamic diameter 2.5–10 μm; PM_10–2.5), for which monitoring is limited before 1999. To address these limitations, we developed spatiotemporal models to predict monthly outdoor PM_2.5 and PM_10–2.5 concentrations for the northeastern and midwestern United States.

Methods

For PM_2.5, we developed models for two periods: 1988–1998 and 1999–2002. Both models included smooth spatial and regression terms of geographic information system-based and meteorologic predictors. To compensate for sparse monitoring data, the pre-1999 model also included predicted PM₁₀ (PM with aerodynamic diameter < 10 μm) and extinction coefficients (km⁻¹). PM_10–2.5 levels were estimated as the difference in monthly predicted PM₁₀ and PM_2.5, with predicted PM₁₀ from our previously developed PM₁₀ model.

Results

Predictive performance for PM_2.5 was strong (cross-validation R² = 0.77 and 0.69 for post-1999 and pre-1999 PM_2.5 models, respectively) with high precision (2.2 and 2.7 μg/m³, respectively). Models performed well irrespective of population density and season. Predictive performance for PM_10–2.5 was weaker (cross-validation R² = 0.39) with lower precision (5.5 μg/m³). PM_10–2.5 levels exhibited greater local spatial variability than PM₁₀ or PM_2.5, suggesting that PM_2.5 measurements at ambient monitoring sites are more representative for surrounding populations than for PM₁₀ and especially PM_10–2.5.

Conclusions

We provide semiempirical models to predict spatially and temporally resolved long-term average outdoor concentrations of PM_2.5 and PM_10–2.5 for estimating exposures of populations living in the northeastern and midwestern United States.     

Disparities in Access to HIV Prevention Among Men of Mexican Descent Living in the Midwestern United States

Men of Mexican descent (MMD) in the U.S. are disproportionately affected by HIV. Understanding MMD’s access to HIV prevention is necessary to reduce their transmission rates. We explored disparities in access to HIV prevention among MMD of different assimilation status, healthcare access, and sexual risk behavior. 322 Midwestern MMD completed a survey assessing their access to passive interventions (e.g., lectures), interactive interventions (e.g., counseling), HIV testing, media information, and information from the Internet. 64% MMD had received passive interventions, 36% interactive interventions, 42% HIV testing, 41% information from media, and 12% from the Internet. MMD who were less assimilated to the U.S., had lower healthcare access, and were at risk for HIV, were less likely to have accessed prevention interventions but more likely to have received media information. Access to HIV prevention among Midwestern MMD is tied to their assimilation and healthcare access. Findings have implications for developing strategies of intervention delivery.     

Increased diversity of zoonotic pathogens and Borrelia burgdorferi strains in established versus incipient Ixodes scapularis populations across the Midwestern United States

The center of origin theory predicts that genetic diversity will be greatest near a specie’s geographic origin because of the length of time for evolution. By corollary, diversity will decrease with distance from the origin; furthermore, invasion and colonization are frequently associated with founder effects that reduce genetic variation in incipient populations. The blacklegged tick, Ixodes scapularis, harbors a suite of zoonotic pathogens, and the geographic range of the tick is expanding in the upper Midwestern United States. Therefore, we posited that diversity of I. scapularis-borne pathogens across its Midwestern range should correlate with the rate of the range expansion of this tick as well as subsequent disease emergence. Analysis of 1565 adult I. scapularis ticks from 13 sites across five Midwestern states revealed that tick infection prevalence with multiple microbial agents (Borrelia burgdorferi, Borrelia miyamotoi, Babesia odocoilei, Babesia microti, and Anaplasma phagocytophilum), coinfections, and molecular genetic diversity of B. burgdorferi all were positively correlated with the duration of establishment of tick populations, and therefore generally support the center of origin – pathogen diversity hypothesis. The observed differences across the gradient of establishment, however, were not strong and were nuanced by the high frequency of coinfections in tick populations at both established and recently-invaded tick populations. These results suggest that the invasion of ticks and their associated pathogens likely involve multiple means of pathogen introduction, rather than the conventionally presented scenario whereby infected, invading ticks are solely responsible for introducing pathogens to naïve host populations.     

Context matters: Contrasting behavioral and residential risk factors for Lyme disease between high-incidence states in the Northeastern and Midwestern United States

The dynamics of zoonotic vector-borne diseases are determined by a complex set of parameters including human behavior that may vary with socio-ecological contexts. Lyme disease is the most common vector-borne disease in the United States. The Northeast and upper Midwest are the regions most affected - two areas with differing levels of urbanization and differing sociocultural settings. The probability of being infected with Lyme disease is related to the risk of encounters with Ixodes scapularis ticks infected with Borrelia burgdorferi sensu lato, which reflects both the environmental tick hazard and human behaviors. Herein, we compare behavioral and peridomestic risk factors perceived to influence the risk for human-tick encounters between two high-incidence states in the Northeast (New York and New Jersey) and one high-incidence state in the Midwest (Wisconsin). We used a smartphone application, The Tick App, as a novel survey tool, during spring and summer of 2018. Adaptive human behavior was identified in the relationship between outdoor activities and the use of methods to prevent tick bites. More frequent recreational outdoor activities and gardening (a peridomestic activity) were associated with a 1.4–2.3 times increased likelihood of using personal protective measures to prevent tick bites, when accounting for demographics and previous Lyme diagnosis. Most outdoor activities were more frequently reported by participants from the Midwest (n = 697), representing an older demographic, than the Northeast (n = 396). Participants from the Northeast were less likely to report use of personal protective measures to prevent tick bites, but a larger proportion of participants from the Northeast reported application of environmental pesticides targeting ticks or mosquitoes or other insects on their property (34 % of 279 versus 22 % of 616 participants) and interventions to reduce the presence of peridomestic deer compared to participants from the Midwest (e.g. 20 % of 278 versus 7% of 615 participants reported having a deer proof fence). Participants from the Midwest were more likely to kill rodents on their property (28 % versus 13 %). These differences illustrate the need for further assessment of personal behavior and tick exposure in these two Lyme disease-endemic regions to aid in targeted public health messaging to reduce tick-borne diseases.     

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.     

A Qualitative Description of Pregnancy-Related Social Support Experiences of Low-Income Women with Low Birth Weight Infants in the Midwestern United States

Maternal and Child Health Journal - Objective Low birth weight (LBW) is a significant health problem in the United States, and the incidence is higher in women with low socioeconomic status....