Existing conditions
Ankur Pandya et al.
Health Affairs, October 2013, Pages 1706-1714
Abstract:
In the past several decades, some risk factors for cardiovascular disease have improved, while others have worsened. For example, smoking rates have dropped and treatment rates for cardiovascular disease have increased — factors that have made the disease less fatal. At the same time, Americans’ average body mass index and incidence of diabetes have increased as the population continues to live longer — factors that have made cardiovascular disease more prevalent. To assess the aggregate impact of these opposing trends, we used the nine National Health and Nutrition Examination Survey waves from 1973 to 2010 to forecast total cardiovascular disease risk and prevalence from 2015 to 2030. We found that continued improvements in cardiovascular disease treatment and declining smoking rates will not outweigh the influence of increasing population age and obesity on cardiovascular disease risk. Given an aging population, an obesity epidemic, and declining mortality from the disease, the United States should expect to see a sharp rise in the health care costs, disability, and reductions in quality of life associated with increased prevalence of cardiovascular disease. Policies that target the treatment of high blood pressure and cholesterol and the reduction of obesity will be necessary to curb the imminent spike in cardiovascular disease prevalence.
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Pounds That Kill: The External Costs of Vehicle Weight
Michael Anderson & Maximilian Auffhammer
Review of Economic Studies, forthcoming
Abstract:
Heavier vehicles are safer for their own occupants but more hazardous for other vehicles. Simple theory thus suggests that an unregulated vehicle fleet is inefficiently heavy. Using three separate identification strategies we show that, controlling for own-vehicle weight, being hit by a vehicle that is 1,000 pounds heavier generates a 40-50% increase in fatality risk. These results imply a total accident-related externality that exceeds the estimated social cost of U.S. carbon emissions and is equivalent to a gas tax of $0.97 per gallon ($136 billion annually). We consider two policies for internalizing this external cost, a weight-varying mileage tax and a gas tax, and find that they are similar for most vehicles. The findings suggest that European gas taxes may be much closer to optimal levels than the U.S. gas tax.
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Greasy Roads: The Impact of Bad Financial News on Road Traffic Accidents
Sotiris Vandoros, Georgios Kavetsos & Paul Dolan
Risk Analysis, forthcoming
Abstract:
We use evidence from a natural experiment in Greece to study the effect of the announcement of austerity measures on road traffic accidents (RTAs). We use daily RTA data from 2010 and 2011, during which a number of austerity measures were announced, including salary and pension cuts and an increase in direct and indirect taxes. We find that controlling for other factors potentially influencing RTAs, the number of RTAs increased significantly on the first two days following the announcements of austerity measures. We put forward some tentative suggestions for why this happens.
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Ivana Igic, Samuel Ryser & Achum Elfering
Journal of Occupational Health Psychology, October 2013, Pages 469-480
Abstract:
Body height decreases throughout the day due to fluid loss from the intervertebral disk. This study investigated whether spinal shrinkage was greater during workdays compared with nonwork days, whether daily work stressors were positively related to spinal shrinkage, and whether job control was negatively related to spinal shrinkage. In a consecutive 2-week ambulatory field study, including 39 office employees and 512 days of observation, spinal shrinkage was measured by a stadiometer, and calculated as body height in the morning minus body height in the evening. Physical activity was monitored throughout the 14 days by accelerometry. Daily work stressors, daily job control, biomechanical workload, and recreational activities after work were measured with daily surveys. Multilevel regression analyses showed that spinal disks shrank more during workdays than during nonworkdays. After adjustment for sex, age, body weight, smoking status, biomechanical work strain, and time spent on physical and low-effort activities during the day, lower levels of daily job control significantly predicted increased spinal shrinkage. Findings add to knowledge on how work redesign that increases job control may possibly contribute to preserving intervertebral disk function and preventing occupational back pain.
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Emotion suppression and mortality risk over a 12-year follow-up
Benjamin Chapman et al.
Journal of Psychosomatic Research, October 2013, Pages 381–385
Objective: Suppression of emotion has long been suspected to have a role in health, but empirical work has yielded mixed findings. We examined the association between emotion suppression and all-cause, cardiovascular, and cancer mortality over 12 years of follow-up in a nationally representative US sample.
Methods: We used the 2008 General Social Survey–National Death Index (GSS–NDI) cohort, which included an emotion suppression scale administered to 729 people in 1996. Prospective mortality follow up between 1996 and 2008 of 111 deaths (37 by cardiovascular disease, 34 by cancer) was evaluated using Cox proportional hazards models adjusted for age, gender, education, and minority race/ethnicity.
Results: The 75th vs. 25th percentile on the emotional suppression score was associated with hazard ratio (HR) of 1.35 (95% Confidence Interval [95% CI] = 1.00, 1.82; P = .049) for all-cause mortality. For cancer and cardiovascular disease mortality, the HRs were 1.70 (95% CI = 1.01, 2.88, P = .049) and 1.47 (95% CI = .87, 2.47, P = .148) respectively.
Conclusions: Emotion suppression may convey risk for earlier death, including death from cancer. Further work is needed to better understand the biopsychosocial mechanisms for this risk, as well as the nature of associations between suppression and different forms of mortality.
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The State of US Health, 1990-2010: Burden of Diseases, Injuries, and Risk Factors
Christopher Murray et al.
Journal of the American Medical Association, 14 August 2013, Pages 591-608
Objectives: To measure the burden of diseases, injuries, and leading risk factors in the United States from 1990 to 2010 and to compare these measurements with those of the 34 countries in the Organisation for Economic Co-operation and Development (OECD) countries.
Design: We used the systematic analysis of descriptive epidemiology of 291 diseases and injuries, 1160 sequelae of these diseases and injuries, and 67 risk factors or clusters of risk factors from 1990 to 2010 for 187 countries developed for the Global Burden of Disease 2010 Study to describe the health status of the United States and to compare US health outcomes with those of 34 OECD countries. Years of life lost due to premature mortality (YLLs) were computed by multiplying the number of deaths at each age by a reference life expectancy at that age. Years lived with disability (YLDs) were calculated by multiplying prevalence (based on systematic reviews) by the disability weight (based on population-based surveys) for each sequela; disability in this study refers to any short- or long-term loss of health. Disability-adjusted life-years (DALYs) were estimated as the sum of YLDs and YLLs. Deaths and DALYs related to risk factors were based on systematic reviews and meta-analyses of exposure data and relative risks for risk-outcome pairs. Healthy life expectancy (HALE) was used to summarize overall population health, accounting for both length of life and levels of ill health experienced at different ages.
Results: US life expectancy for both sexes combined increased from 75.2 years in 1990 to 78.2 years in 2010; during the same period, HALE increased from 65.8 years to 68.1 years. The diseases and injuries with the largest number of YLLs in 2010 were ischemic heart disease, lung cancer, stroke, chronic obstructive pulmonary disease, and road injury. Age-standardized YLL rates increased for Alzheimer disease, drug use disorders, chronic kidney disease, kidney cancer, and falls. The diseases with the largest number of YLDs in 2010 were low back pain, major depressive disorder, other musculoskeletal disorders, neck pain, and anxiety disorders. As the US population has aged, YLDs have comprised a larger share of DALYs than have YLLs. The leading risk factors related to DALYs were dietary risks, tobacco smoking, high body mass index, high blood pressure, high fasting plasma glucose, physical inactivity, and alcohol use. Among 34 OECD countries between 1990 and 2010, the US rank for the age-standardized death rate changed from 18th to 27th, for the age-standardized YLL rate from 23rd to 28th, for the age-standardized YLD rate from 5th to 6th, for life expectancy at birth from 20th to 27th, and for HALE from 14th to 26th.
Conclusions and Relevance: From 1990 to 2010, the United States made substantial progress in improving health. Life expectancy at birth and HALE increased, all-cause death rates at all ages decreased, and age-specific rates of years lived with disability remained stable. However, morbidity and chronic disability now account for nearly half of the US health burden, and improvements in population health in the United States have not kept pace with advances in population health in other wealthy nations.
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Hygiene and the world distribution of Alzheimer's Disease
Molly Fox et al.
Evolution, Medicine, and Public Health, 2013, Pages 173-186
Background and objectives: Alzheimer's Disease (AD) shares certain etiological features with autoimmunity. Prevalence of autoimmunity varies between populations in accordance with variation in environmental microbial diversity. Exposure to microorganisms may improve individuals' immunoregulation in ways that protect against autoimmunity, and we suggest this may also be the case for AD. Here we investigate whether differences in microbial diversity can explain patterns of age-adjusted AD rates between countries.
Methodology: We use regression models to test whether pathogen prevalence, as a proxy for microbial diversity, across 192 countries can explain a significant amount of the variation in age-standardized AD disability-adjusted life-year (DALY) rates. We also review and assess the relationship between pathogen prevalence and AD rates in different world populations.
Results: Based on our analyses, it appears that hygiene is positively associated with AD risk. Countries with greater degree of sanitation and lower degree of pathogen prevalence have higher age-adjusted AD DALY rates. Countries with greater degree of urbanization and wealth exhibit higher age-adjusted AD DALY rates.
Conclusions and implications: Variation in hygiene may partly explain global patterns in AD rates. Microorganism exposure may be inversely related to AD risk. These results may help predict AD burden in developing countries where microbial diversity is rapidly diminishing. Epidemiological forecasting is important for preparing for future healthcare needs and research prioritization.
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Life Expectancy and Human Capital: Evidence from the International Epidemiological Transition
Casper Worm Hansen
Journal of Health Economics, forthcoming
Abstract:
Exploiting preintervention variation in mortality from various infectious diseases, together with the time variation arising from medical breakthroughs in the late 1940s and the 1950s, this study examines how a large positive shock to life expectancy influenced the formation of human capital within countries during the second half of the 20th century. The results establish that the rise in life expectancy was behind a significant part of the increase in human capital over this period. According to the baseline estimate, for one additional year of life expectancy, years of schooling increase by 0.17 years. Moreover, the evidence suggests that declines in pneumonia mortality are the underlying cause of this finding, indicating that improved childhood health increases human capital investments.
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The effect of household hospitalizations on the educational attainment of youth
Eric Johnson & Lockwood Reynolds
Economics of Education Review, forthcoming
Abstract:
We utilize data from the NLSY97 to investigate the effect of week-long hospitalizations of household members on the educational attainment of youth. These significant household health events could result in a combination of financial and time constraints on the household, limiting the educational opportunities available to survey respondents. We find that household hospitalizations lead to reductions in the likelihood of completing high school, attending college and completing a bachelor's degree. These negative effects are disproportionately experienced by male respondents. Respondents with higher pre-hospitalization ability appear to be insulated from these health events. Birth-order and the gender composition of siblings also appear to play a role. We find that the oldest children in the household bear the burden of a hospitalization, substantially lowering the educational attainment of these respondents, while insulating their younger siblings. Similarly, the presence of a brother appears to insulate respondents from the negative impacts of household hospitalizations.
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Dana Goldman et al.
Health Affairs, October 2013, Pages 1698-1705
Abstract:
Recent scientific advances suggest that slowing the aging process (senescence) is now a realistic goal. Yet most medical research remains focused on combating individual diseases. Using the Future Elderly Model — a microsimulation of the future health and spending of older Americans — we compared optimistic “disease specific” scenarios with a hypothetical “delayed aging” scenario in terms of the scenarios’ impact on longevity, disability, and major entitlement program costs. Delayed aging could increase life expectancy by an additional 2.2 years, most of which would be spent in good health. The economic value of delayed aging is estimated to be $7.1 trillion over fifty years. In contrast, addressing heart disease and cancer separately would yield diminishing improvements in health and longevity by 2060 — mainly due to competing risks. Delayed aging would greatly increase entitlement outlays, especially for Social Security. However, these changes could be offset by increasing the Medicare eligibility age and the normal retirement age for Social Security. Overall, greater investment in research to delay aging appears to be a highly efficient way to forestall disease, extend healthy life, and improve public health.
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Dietary Sodium Restriction: Take It with a Grain of Salt
James DiNicolantonio et al.
American Journal of Medicine, November 2013, Pages 951–955
Abstract:
The American Heart Association recently strongly recommended a dietary sodium intake of <1500 mg/d for all Americans to achieve “Ideal Cardiovascular Health” by 2020. However, low sodium diets have not been shown to reduce cardiovascular events in normotensive individuals or in individuals with pre-hypertension or hypertension. Moreover, there is evidence that a low sodium diet may lead to a worse cardiovascular prognosis in patients with cardiometabolic risk and established cardiovascular disease. Low sodium diets may adversely affect insulin resistance, serum lipids, and neurohormonal pathways, leading to increases in the incidence of new cardiometabolic disease, the severity of existing cardiometabolic disease, and greater cardiovascular and all-cause mortality. Although a high sodium intake also may be deleterious, there is good reason to believe that sodium intake is regulated within such a tight physiologic range that there is little risk to leaving sodium intake to inherent biology as opposed to likely futile attempts at conscious control.
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Frequency of prolonged social-evaluative threat and cytokine activity: A field experiment
L. Frimanson, I. Anderzén & M. Lekander
Brain, Behavior, and Immunity, September 2013, Pages e13
Abstract:
Healthy subordinates in a work organization completed a 1-year treatment of maintained high-frequent (n = 39, M = 8.81, SD = 0.61) or low-frequent (n = 39, M = 4.56, SD = 2.01) evaluation of work performance (HFE or LFE, respectively, p < .001). Subjects did not differ significantly in demographics, health behaviors, and baseline Interleukin-6 production (IL-6), ps > .364. IL-6 was not correlated with health behaviors at baseline or after 12 months in response to the stressor, ps > .068. Results: There was a significant Time X Condition interaction for IL-6, F (2, 75) = 3.82, p > .027, partial eta squared = .092. HFE subjects showed non-significant increases in IL-6 from baseline to 6 months, p > .394, and 12 months, p > .142. LFE subjects showed significant decreases in IL-6 from baseline to 6 months, t (38) = −2.36, p < .023, and 12 months, t (38) = −3.21, p < .004. After 6 months, IL-6 in HFE (M = 1.28, SD = 1.32) and LFE (M = 0.97, SD = 0.51) conditions were significantly different, F (1, 75) = 4.30, p < .042, and after 12 months this significant difference between HFE (M = 1.44, SD = 1.69) and LFE (M = 0.94, SD = 0.40) conditions increased further, F (1, 75) = 7.25, p < .010, partial eta squared = .088 (controlling for baseline IL-6). These findings suggest that prolonged social evaluation is a potent threat capable of influencing cytokine activity, and that this influence is associated with evaluation frequency.
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Voter demand for fluoridated water: A tale of two c(av)ities
Philip Hersch & Jodi Pelkowski
Applied Economics Letters, Winter 2013, Pages 51-54
Abstract:
Government fluoridation of public water systems to promote dental health has long been advocated by many health associations, based on the findings of mainstream scientific studies. Despite this, fluoridation remains a controversial issue. Some in the public are antithetical to the science behind fluoridation while others view it as an infringement on individual choice. Voting data from referendums in two of the six largest US cities without fluoridated water (Portland, Oregon, and Wichita, Kansas) are used to examine the factors driving voter demand for and against fluoridation. Although regression analysis reveals differences between the cities, a strong commonality is greater support for fluoride coming from voting precincts with higher concentrations of college graduates. Additionally, even though advocates often laud water fluoridation as a relatively inexpensive way to extend dental health benefits to all children (regardless of income levels), presence of children in households surprisingly does not appear to translate into voter support. Lastly, after controlling for socio-economic factors, results suggest that opposition to fluoridation does not appear to come from the political centre, but from the libertarian right and environmental left.
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Life Expectancy, Schooling, and Lifetime Labor Supply: Theory and Evidence Revisited
Matteo Cervellati & Uwe Sunde
Econometrica, September 2013, Pages 2055–2086
Abstract:
This paper presents a theoretical and empirical analysis of the role of life expectancy for optimal schooling and lifetime labor supply. The results of a simple prototype Ben-Porath model with age-specific survival rates show that an increase in lifetime labor supply is not a necessary, or a sufficient, condition for greater life expectancy to increase optimal schooling. The observed increase in survival rates during working ages that follows from the “rectangularization” of the survival function is crucial for schooling and labor supply. The empirical results suggest that the relative benefits of schooling have been increasing across cohorts of U.S. men born between 1840 and 1930. A simple quantitative analysis shows that a realistic shift in the survival function can lead to an increase in schooling and a reduction in lifetime labor hours.
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A Dam Problem: TVA's Fight Against Malaria, 1926–1951
Carl Kitchens
Journal of Economic History, September 2013, Pages 694-724
Abstract:
The TVA has been applauded for its anti-malaria programs in the Southeast during the 1930s and 1940s. However, the TVA developed their anti-malaria programs because they created lakes suitable for mosquito breeding. To estimate the relationship between the TVA and malaria, I construct a county-level panel data from the Southeast United States. I find that the net effect of the TVA was to increase malaria rates following its construction. Using statistical life value estimates, I find that the hidden malaria cost of the TVA offset 24 percent of the fiscal stimulus multiplier generated by the TVA.
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Martin Hugo Saavedra
University of Pittsburgh Working Paper, August 2013
Abstract:
Using city-of-birth data from the 100-percent sample of the 1880 Census merged to city-level fatality counts, I estimate the effect of early-life yellow fever exposure on adult occupational status. I find that in utero, neonatal, or postnatal yellow fever exposure decreased adult occupational status for white males with foreign-born mothers, whereas white males with U.S.-born mothers were relatively unaffected. Furthermore, I find no evidence that epidemics 2 to 4 years after birth affect adult occupational status.
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FKBP5 and CRHR1 Polymorphisms Moderate the Stress–Physical Health Association in a National Sample
Jared Lessard & Alison Holman
Health Psychology, forthcoming
Objective: Stressful life events experienced during childhood and as an adult negatively impact mental and physical health over the life span. This study examined polymorphisms from 2 hypothalamic–pituitary–adrenal axis-related genes previously associated with posttraumatic stress disorder — FKBP5 and CRHR1 — as moderators of the impact of child abuse and adult stress on physical health.
Method: A national, community-based subsample of non-Hispanic European American respondents (n = 527) from a prospective longitudinal 3-year study of stress and coping (N = 2,729) provided saliva for genotyping.
Results: FKBP5 (rs1360780) and CRHR1 (rs12944712) polymorphisms significantly interacted with child abuse and adult stress to predict increases in physical health ailments over 3 years. Child abuse and adult stress were strongly related to physician-diagnosed physical ailments among individuals with the risk alleles of both single nucleotide polymorphisms. Individuals carrying the low-risk homozygotic genotypes were protected from the long-term negative health implications of experiencing both child abuse and adult stress.
Conclusion: Consistent with theories linking the hypothalamic–pituitary–adrenal axis with stress-related disease, hypothalamic–pituitary–adrenal axis polymorphism genotypes moderated the association between exposure to child abuse/adult stress and long-term physical health outcomes in a national sample.
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Perry Hystad et al.
Social Science & Medicine, November 2013, Pages 95–103
Abstract:
Neighbourhood socioeconomic status (SES) has been associated with numerous chronic diseases, yet little information exists on its association with lung cancer incidence. This outcome presents two key empirical challenges: a long latency period that requires study participants’ residential histories and long-term neighbourhood characteristics; and adequate data on many risk factors to test hypothesized mediating pathways between neighbourhood SES and lung cancer incidence. Analyzing data on urban participants of a large Canadian population-based lung cancer case-control study, we investigate three issues pertaining to these challenges. First, we examine whether there is an association between long-term neighbourhood SES, derived from 20 years of residential histories and five national censuses, and lung cancer incidence. Second, we determine how this long-term neighbourhood SES association changes when using neighbourhood SES measures based on different latency periods or at time of study entry. Third, we estimate the extent to which long-term neighbourhood SES is mediated by a range of individual-level smoking behaviours, other health behaviours, and environmental and occupational exposures. Results of hierarchical logistic regression models indicate significantly higher odds of lung cancer cases residing in the most compared to the least deprived quintile of the long-term neighbourhood SES index (OR: 1.46; 95% CI: 1.13-1.89) after adjustment for individual SES. This association remained significant (OR: 1.38; 1.01-1.88) after adjusting for smoking behaviour and other known and suspected lung cancer risk factors. Important differences were observed between long-term and study entry neighbourhood SES measures, with the latter attenuating effect estimates by over 50 percent. Smoking behaviour was the strongest partial mediating pathway of the long-term neighbourhood SES effect. This research is the first to examine the effects of long-term neighbourhood SES on lung cancer risk and more research is needed to further identify specific, modifiable pathways by which neighbourhood context may influence lung cancer risk.
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Adult Stature and Risk of Cancer at Different Anatomic Sites in a Cohort of Postmenopausal Women
Geoffrey Kabat et al.
Cancer Epidemiology, Biomarkers & Prevention, August 2013, Pages 1353-1363
Background: Prospective studies in Western and Asian populations suggest that height is a risk factor for various cancers. However, few studies have explored potential confounding or effect modification of the association by other factors.
Methods: We examined the association between height measured at enrollment in 144,701 women participating in the Women's Health Initiative and risk of all cancers combined and cancer at 19 specific sites. Over a median follow-up of 12.0 years, 20,928 incident cancers were identified. We used Cox proportional hazards models to estimate HR and 95% confidence intervals (CI) per 10 cm increase in height, with adjustment for established risk factors. We also examined potential effect modification of the association with all cancer and specific cancers.
Results: Height was significantly positively associated with risk of all cancers (HR = 1.13; 95% CI, 1.11–1.16), as well as with cancers of the thyroid, rectum, kidney, endometrium, colorectum, colon, ovary, and breast, and with multiple myeloma and melanoma (range of HRs: 1.13 for breast cancer to 1.29 for multiple myeloma and thyroid cancer). These associations were generally insensitive to adjustment for confounders, and there was little evidence of effect modification.
Conclusions: This study confirms the positive association of height with risk of all cancers and a substantial number of cancer sites.
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Federal Food Package Revisions: Effects on Purchases of Whole-Grain Products
Tatiana Andreyeva & Joerg Luedicke
American Journal of Preventive Medicine, October 2013, Pages 422–429
Background: In 2009, the U.S. Department of Agriculture’s Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) implemented revisions to the composition and quantities of WIC-provided foods. New whole-grain products such as whole-wheat bread and allowable substitutes were added to encourage increased intake of whole grains and fiber among WIC participants.
Purpose: This paper assesses how the WIC revisions affected purchases of bread and rice among WIC-participating households in Connecticut and Massachusetts.
Methods: Scanner data from a regional supermarket chain were used to examine bread and rice purchases of 2137 WIC households. Purchased volume of bread and rice was compared before and after implementation of the WIC revisions (2009–2010) using generalized estimating equation models. Data were analyzed in 2013.
Results: Before the WIC revisions, when no bread or rice was provided through WIC, white bread dominated bread purchases among WIC households (78% of volume), and almost all rice purchased was white (94%). As a result of the WIC revisions, the share of 100% whole-grain bread in total bread purchases tripled (from 8% to 24%), replacing purchases of white bread; the share of brown rice rose to 30% of rice purchases. WIC households used WIC benefits to change some of their bread purchases, rather than to buy more bread overall, whereas total rice purchases increased.
Conclusions: The 2009 WIC revisions significantly increased purchases of whole-grain bread and rice among WIC-participating families. The likely increase in whole-grain and fiber intake among low-income communities could have important public health implications.
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Predicting the public health benefit of vaccinating cattle against Escherichia coli O157
Louise Matthews et al.
Proceedings of the National Academy of Sciences, 1 October 2013, Pages 16265-16270
Abstract:
Identifying the major sources of risk in disease transmission is key to designing effective controls. However, understanding of transmission dynamics across species boundaries is typically poor, making the design and evaluation of controls particularly challenging for zoonotic pathogens. One such global pathogen is Escherichia coli O157, which causes a serious and sometimes fatal gastrointestinal illness. Cattle are the main reservoir for E. coli O157, and vaccines for cattle now exist. However, adoption of vaccines is being delayed by conflicting responsibilities of veterinary and public health agencies, economic drivers, and because clinical trials cannot easily test interventions across species boundaries, lack of information on the public health benefits. Here, we examine transmission risk across the cattle–human species boundary and show three key results. First, supershedding of the pathogen by cattle is associated with the genetic marker stx2. Second, by quantifying the link between shedding density in cattle and human risk, we show that only the relatively rare supershedding events contribute significantly to human risk. Third, we show that this finding has profound consequences for the public health benefits of the cattle vaccine. A naïve evaluation based on efficacy in cattle would suggest a 50% reduction in risk; however, because the vaccine targets the major source of human risk, we predict a reduction in human cases of nearly 85%. By accounting for nonlinearities in transmission across the human–animal interface, we show that adoption of these vaccines by the livestock industry could prevent substantial numbers of human E. coli O157 cases.