Transmission of viral pathogens in a social network of university students: the eX-FLU study.

Previous research on respiratory infection transmission among university students has primarily focused on influenza. In this study, we explore potential transmission events for multiple respiratory pathogens in a social contact network of university students. University students residing in on-campus housing (n = 590) were followed for the development of influenza-like illness for 10-weeks during the 2012-13 influenza season. A contact network was built using weekly self-reported contacts, class schedules, and housing information. We considered a transmission event to have occurred if students were positive for the same pathogen and had a network connection within a 14-day period. Transmitters were individuals who had onset date prior to their infected social contact. Throat and nasal samples were analysed for multiple viruses by RT-PCR. Five viruses were involved in 18 transmission events (influenza A, parainfluenza virus 3, rhinovirus, coronavirus NL63, respiratory syncytial virus). Transmitters had higher numbers of co-infections (67%). Identified transmission events had contacts reported in small classes (33%), dormitory common areas (22%) and dormitory rooms (17%). These results suggest that targeting person-to-person interactions, through measures such as isolation and quarantine, could reduce transmission of respiratory infections on campus.

Largest GWAS of PTSD (N=20 070) yields genetic overlap with schizophrenia and sex differences in heritability.

The Psychiatric Genomics Consortium-Posttraumatic Stress Disorder group (PGC-PTSD) combined genome-wide case-control molecular genetic data across 11 multiethnic studies to quantify PTSD heritability, to examine potential shared genetic risk with schizophrenia, bipolar disorder, and major depressive disorder and to identify risk loci for PTSD. Examining 20 730 individuals, we report a molecular genetics-based heritability estimate (h2SNP) for European-American females of 29% that is similar to h2SNP for schizophrenia and is substantially higher than h2SNP in European-American males (estimate not distinguishable from zero). We found strong evidence of overlapping genetic risk between PTSD and schizophrenia along with more modest evidence of overlap with bipolar and major depressive disorder. No single-nucleotide polymorphisms (SNPs) exceeded genome-wide significance in the transethnic (overall) meta-analysis and we do not replicate previously reported associations. Still, SNP-level summary statistics made available here afford the best-available molecular genetic index of PTSD-for both European- and African-American individuals-and can be used in polygenic risk prediction and genetic correlation studies of diverse phenotypes. Publication of summary statistics for ∼10 000 African Americans contributes to the broader goal of increased ancestral diversity in genomic data resources. In sum, the results demonstrate genetic influences on the development of PTSD, identify shared genetic risk between PTSD and other psychiatric disorders and highlight the importance of multiethnic/racial samples. As has been the case with schizophrenia and other complex genetic disorders, larger sample sizes are needed to identify specific risk loci.

Persistent socioeconomic and racial and ethnic disparities in pathogen burden in the United States, 1999-2014.

The disproportionate burden of prevalent, persistent pathogens among disadvantaged groups may contribute to socioeconomic and racial/ethnic disparities in long-term health. We assessed if the social patterning of pathogen burden changed over 16 years in a U.S.-representative sample. Data came from 17 660 National Health and Nutrition Examination Survey participants. Pathogen burden was quantified by summing the number of positive serologies for cytomegalovirus, herpes simplex virus-1, HSV-2, human papillomavirus and Toxoplasma gondii and dividing by the number of pathogens tested, giving a percent-seropositive for each participant. We examined sex- and age-adjusted mean pathogen burdens from 1999-2014, stratified by race/ethnicity and SES (poverty-to-income ratio (PIR); educational attainment). Those with a PIR < 1.3 had a mean pathogen burden 1.4-1.8 times those with a PIR > 3.5, with no change over time. Educational disparities were even greater and showed some evidence of increasing over time, with the mean pathogen burden among those with less than a high school education approximately twice that of those who completed more than high school. Non-Hispanic Black, Mexican American and other Hispanic participants had a mean pathogen burden 1.3-1.9 times non-Hispanic Whites. We demonstrate that socioeconomic and racial/ethnic disparities in pathogen burden have persisted across 16 years, with little evidence that the gap is closing.

Investigating pathogen burden in relation to a cumulative deficits index in a representative sample of US adults.

Pathogen burden is a construct developed to assess the cumulative effects of multiple, persistent pathogens on morbidity and mortality. Despite the likely biological wear and tear on multiple body systems caused by persistent infections, few studies have examined the impact of total pathogen burden on such outcomes and specifically on preclinical markers of dysfunction. Using data from two waves of the National Health and Nutrition Examination Survey, we compared three alternative methods for measuring pathogen burden, composed of mainly persistent viral infections, using a cumulative deficits index (CDI) as an outcome: single pathogen associations, a pathogen burden summary score and latent class analyses. We found significant heterogeneity in the distribution of the CDI by age, sex, race/ethnicity and education. There was an association between pathogen burden and the CDI by all three metrics. The latent class classification of pathogen burden showed particularly strong associations with the CDI; these associations remained after controlling for age, sex, body mass index, smoking, race/ethnicity and education. Our results suggest that pathogen burden may influence early clinical indicators of poor health as measured by the CDI. Our results are salient since we were able to detect these associations in a relatively young population. These findings suggest that reducing pathogen burden and the specific pathogens that drive the CDI may provide a target for preventing the early development of age-related physiological changes.

Pathways from assaultive violence to post-traumatic stress, depression, and generalized anxiety symptoms through stressful life events: longitudinal mediation models.

BACKGROUND: Assaultive violence events are associated with increased risk for adverse psychiatric outcomes, including post-traumatic stress (PTS), depression, and generalized anxiety. Prior research has indicated that economic, legal, and social stressors that could follow assaultive events may explain the increased risk for adverse psychiatric outcomes, yet longitudinal studies have not adequately examined this pathway. In the current study, we aimed to address this limitation. METHODS: Participants (N = 1360) were part of a longitudinal population-based study of adults living in Detroit. At three waves, participants indicated their exposure to assaultive violence and economic, legal, and social stressors, and completed inventories of PTS, depression, and generalized anxiety. Longitudinal mediation models were used to test the hypothesized pathway from assaultive violence to each psychiatric outcome. RESULTS: The hypothesized models evidenced good fit with the data and, in each, the paths from Wave 1 (W1) assaultive violence to W2 stressors, and from W2 stressors to W3 symptoms were significant (range of Standardized Estimates: 0.09-0.15, all p < 0.01). Additionally, the indirect paths from W1 assaultive violence to W3 symptoms were significant (range of Standardized Estimates: 0.01-0.02, all p < 0.05). CONCLUSIONS: The findings illustrate that the economic, legal, and social stressors that could follow assaultive violence increase risk for a range of psychiatric symptoms. Although future research is needed, the results suggest that investment in interventions that prevent and mitigate assaultive violence survivors' exposure to such stressors may be an effective way to prevent mental illness in the aftermath of violent assaults.

The impact of pathogen burden on leukocyte telomere length in the Multi-Ethnic Study of Atherosclerosis.

Several infections have been linked to telomere shortening and in some cases these associations have varied by sex. We assessed the association between seropositivity to four persistent pathogens (cytomegalovirus (CMV), herpes simplex virus-1, Helicobacter pylori, Chlamydia pneumoniae), and total pathogen burden on leukocyte telomere length in a diverse US sample. Data came from the Multi-Ethnic Study of Atherosclerosis, a population-based cohort study. We utilized cross-sectional survey data, and biological samples from participants tested for pathogens and telomere length (N = 163). Linear regression was used to examine the association between seropositivity for individual pathogens as well as total pathogen burden and telomere length, adjusting for various confounders. CMV seropositivity and increased total pathogen burden level were significantly associated with shorter telomere length among females (ß = -0·1204 (standard error (s.e.) 0·06), P = 0·044) and (ß = -0·1057 (s.e. = 0·05), P = 0·033), respectively. There was no statistically significant association among males. Our findings suggest that prevention or treatment of persistent pathogens, in particular CMV, may play an important role in reducing telomere shortening over the life course among women. Future research is needed to confirm these novel findings in larger longitudinal samples.

Unpacking the 'black box' of total pathogen burden: is number or type of pathogens most predictive of all-cause mortality in the United States?

A 'black box' paradigm has prevailed in which researchers have focused on the association between the total number of pathogens for which individuals are seropositive (i.e. total pathogen burden) and various chronic diseases, while largely ignoring the role that seropositivity for specific combinations of pathogens may play in the aetiology of such outcomes and consequently mortality. We examined the association between total pathogen burden as well as specific pathogen combinations and all-cause mortality in the United States. Data were from individuals aged ⩾25 years tested for cytomegalovirus (CMV), herpes simplex virus (HSV)-1, HSV-2 and Helicobacter pylori, with mortality follow-up to 31 December 2006 in the National Health and Nutrition Examination Survey (NHANES) III (N = 6522). We did not observe a statistically significant graded relationship between total pathogen burden level and all-cause mortality. Furthermore, compared to those seronegative for all four pathogens, the greatest statistically significant rate of all-cause mortality was for those CMV+/HSV-2+ (hazard ratio 1·95, 95% confidence interval 1·13-3·35) adjusting for age, gender, race/ethnicity, education level, body mass index (kg/m2) and smoking status. Interventions targeting prevention or treatment of particular pathogens may be more effective for reducing mortality than those focused solely on reducing overall pathogen burden.

Longitudinal epigenetic variation of DNA methyltransferase genes is associated with vulnerability to post-traumatic stress disorder.

BACKGROUND: Epigenetic differences exist between trauma-exposed individuals with and without post-traumatic stress disorder (PTSD). It is unclear whether these epigenetic differences pre-exist, or arise following, trauma and PTSD onset. METHOD: In pre- and post-trauma samples from a subset of Detroit Neighborhood Health Study participants, DNA methylation (DNAm) was measured at DNA methyltransferase 1 (DNMT1), DNMT3A, DNMT3B and DNMT3L. Pre-trauma DNAm differences and changes in DNAm from pre- to post-trauma were assessed between and within PTSD cases (n = 30) and age-, gender- and trauma exposure-matched controls (n = 30). Pre-trauma DNAm was tested for association with post-trauma symptom severity (PTSS) change. Potential functional consequences of DNAm differences were explored via bioinformatic search for putative transcription factor binding sites (TFBS). RESULTS: DNMT1 DNAm increased following trauma in PTSD cases (p = 0.001), but not controls (p = 0.067). DNMT3A and DNMT3B DNAm increased following trauma in both cases (DNMT3A: p = 0.009; DNMT3B: p < 0.001) and controls (DNMT3A: p = 0.002; DNMT3B: p < 0.001). In cases only, pre-trauma DNAm was lower at a DNMT3B CpG site that overlaps with a TFBS involved in epigenetic regulation (p = 0.001); lower pre-trauma DNMT3B DNAm at this site was predictive of worsening of PTSS post-trauma (p = 0.034). Some effects were attenuated following correction for multiple hypothesis testing. CONCLUSIONS: DNAm among trauma-exposed individuals shows both longitudinal changes and pre-existing epigenetic states that differentiate individuals who are resilient versus susceptible to PTSD. These distinctive DNAm differences within DNMT loci may contribute to genome-wide epigenetic profiles of PTSD.

Hand hygiene and risk of influenza virus infections in the community: a systematic review and meta-analysis.

Community-based prevention strategies for seasonal and pandemic influenza are essential to minimize their potential threat to public health. Our aim was to evaluate the efficacy of hand hygiene interventions in reducing influenza transmission in the community and to investigate the possible modifying effects of latitude, temperature and humidity on hand hygiene efficacy. We identified 979 articles in the initial search and 10 randomized controlled trials met our inclusion criteria. The combination of hand hygiene with facemasks was found to have statistically significant efficacy against laboratory-confirmed influenza while hand hygiene alone did not. Our meta-regression model did not identify statistically significant effects of latitude, temperature or humidity on the efficacy of hand hygiene. Our findings highlight the potential importance of interventions that protect against multiple modes of influenza transmission, and the modest efficacy of hand hygiene suggests that additional measures besides hand hygiene may also be important to control influenza.

Home foreclosure and risk of psychiatric morbidity during the recent financial crisis.

BACKGROUND: A defining feature of the US economic downturn of 2008-2010 was the alarming rate of home foreclosure. Although a substantial number of US households have experienced foreclosure since 2008, the effects of foreclosure on mental health are unknown. We examined the effects of foreclosure on psychiatric symptomatology in a prospective, population-based community survey. METHOD: Data were drawn from the Detroit Neighborhoods and Health Study (DNHS), waves 1 and 2 (2008-2010). A probability sample of predominantly African-American adults in Detroit, Michigan participated (n=1547). We examined the association between home foreclosure between waves 1 and 2 and increases in symptoms of DSM-IV major depression and generalized anxiety disorder (GAD). RESULTS: The most common reasons for foreclosure were an increase in monthly payments, an increase in non-medical expenses and a reduction in family income. Exposure to foreclosure between waves 1 and 2 predicted symptoms of major depression and GAD at wave 2, controlling for symptoms at wave 1. Even after adjusting for wave 1 symptoms, sociodemographics, lifetime history of psychiatric disorder at wave 1 and exposure to other financial stressors between waves 1 and 2, foreclosure was associated with an increased rate of symptoms of major depression [incidence density ratio (IDR) 2.4, 95% confidence interval (CI) 1.6-3.6] and GAD (IDR 1.9, 95% CI 1.4-2.6). CONCLUSIONS: We provide the first prospective evidence linking foreclosure to the onset of mental health problems. These results, combined with the high rate of home foreclosure since 2008, suggest that the foreclosure crisis may have adverse effects on the mental health of the US population.

Epigenetic and inflammatory marker profiles associated with depression in a community-based epidemiologic sample.

BACKGROUND: Recent work suggests that epigenetic differences may be associated with psychiatric disorders. Here we investigate, in a community-based sample, whether methylation profiles distinguish between individuals with and without lifetime depression. We also investigate the physiologic consequences that may be associated with these profiles. METHOD: Using whole blood-derived genomic DNA from a subset of participants in the Detroit Neighborhood Health Study (DNHS), we applied methylation microarrays to assess genome-wide methylation profiles for over 14 000 genes in 33 persons who reported a lifetime history of depression and 67 non-depressed adults. Bioinformatic functional analyses were performed on the genes uniquely methylated and unmethylated in each group, and inflammatory biomarkers [interleukin (IL)-6 and C-reactive protein (CRP)] were measured to investigate the possible functional significance of the methylation profiles observed. RESULTS: Uniquely unmethylated gene sets distinguished between those with versus without lifetime depression. In particular, some processes (e.g. brain development, tryptophan metabolism) showed patterns suggestive of increased methylation among individuals with depression whereas others (e.g. lipoprotein) showed patterns suggestive of decreased methylation among individuals with depression. IL-6 and CRP levels were elevated among those with lifetime depression and, among those with depression only, IL-6 methylation showed an inverse correlation with circulating IL-6 and CRP. CONCLUSIONS: Genome-wide methylation profiles distinguish individuals with versus without lifetime depression in a community-based setting, and show coordinated signals with pathophysiological mechanisms previously implicated in the etiology of this disorder. Examining epigenetic mechanisms in concert with other dynamic markers of physiologic functioning should improve our understanding of the neurobiology of depression.

Face masks to prevent transmission of influenza virus: a systematic review.

Influenza viruses circulate around the world every year. From time to time new strains emerge and cause global pandemics. Many national and international health agencies recommended the use of face masks during the 2009 influenza A (H1N1) pandemic. We reviewed the English-language literature on this subject to inform public health preparedness. There is some evidence to support the wearing of masks or respirators during illness to protect others, and public health emphasis on mask wearing during illness may help to reduce influenza virus transmission. There are fewer data to support the use of masks or respirators to prevent becoming infected. Further studies in controlled settings and studies of natural infections in healthcare and community settings are required to better define the effectiveness of face masks and respirators in preventing influenza virus transmission.

Race/Ethnic and Educational Disparities in the Association Between Pathogen Burden and a Laboratory-Based Cumulative Deficits Index.

BACKGROUND: Disparities in adult morbidity and mortality may be rooted in patterns of biological dysfunction in early life. We sought to examine the association between pathogen burden and a cumulative deficits index (CDI), conceptualized as a pre-clinical marker of an unhealthy biomarker profile, specifically focusing on patterns across levels of social disadvantage. METHODS: Using the data from the National Health and Nutrition Examination Survey 2003-2004 wave (aged 20-49 years), we examined the association of pathogen burden, composed of seven pathogens, with the CDI. The CDI comprised 28 biomarkers corresponding to available clinical laboratory measures. Models were stratified by race/ethnicity and education level. RESULTS: The CDI ranged from 0.04 to 0.78. Nearly half of Blacks were classified in the high burden pathogen class compared with 8% of Whites. Among both Mexican Americans and other Hispanic groups, the largest proportion of individuals were classified in the common pathogens class. Among educational classes, 19% of those with less than a high school education were classified in the high burden class compared with 7% of those with at least a college education. Blacks in the high burden pathogen class had a CDI 0.05 greater than those in the low burden class (P < 0.05). Whites in the high burden class had a CDI only 0.03 greater than those in the low burden class (P < 0.01). DISCUSSION: Our findings suggest there are significant social disparities in the distribution of pathogen burden across race/ethnic groups, and the effects of pathogen burden may be more significant for socially disadvantaged individuals.

The association of parental and offspring educational attainment with systolic blood pressure, fasting blood glucose and waist circumference in Latino adults.

OBJECTIVE: The objective of the study is to evaluate the association of intergenerational educational attainment with cardiovascular disease (CVD) risk factors among US Latinos. METHODS: We used cross-sectional data from the Niños Lifestyle and Diabetes Study, an offspring cohort of middle-aged Mexican-Americans whose parents participated in the Sacramento Latino Study on Aging. We collected educational attainment, demographic and health behaviours and measured systolic blood pressure (SBP), fasting glucose and waist circumference. We evaluated the association of parental, offspring and a combined parent-offspring education variable with each CVD risk factor using multivariable regression. RESULTS: Higher parental education was associated only with smaller offspring waist circumference. In contrast, higher offspring education was associated with lower SBP, fasting glucose and smaller waist circumference. Adjustment for parental health behaviours modestly attenuated these offspring associations, whereas adjustment for offspring health behaviours and income attenuated the associations of offspring education with offspring SBP and fasting glucose but not smaller waist circumference, even among offspring with low parental education. CONCLUSIONS: Higher offspring education is associated with lower levels of CVD risk factors in adulthood, despite intergenerational exposure to low parental education.

Concordance of haemoglobin A1c, blood pressure and C-reactive protein between children and their parents in Chinese households.

BACKGROUND: China has the world's highest diabetes prevalence, which along with hypertension and inflammation continues to grow particularly among children. Little is known about the strength of the association of these cardiometabolic risk factors between parents and their children; thus, the potential of household-based strategies to reduce risk is unknown. OBJECTIVES: The objective of the study is to examine the parent-child association for haemoglobin A1c (HbA1c), blood pressure (BP) and C-reactive protein (CRP) in a large, geographically diverse Chinese sample. METHODS: In 940 parent-child pairs (children aged 7-17 years) who participated in the 2009 China Health and Nutrition Survey, we measured each individual's HbA1c and CRP using fasting blood and BP. We used sex-specific random-effects linear regression to examine the parent-child association for these risk factors, accounting for within-family clustering. RESULTS: Child's HbA1c was positively associated with parental HbA1c. Beta coefficients ranged from 0.06 (95% CI 0.03-0.12) for father-daughter to 0.43 (95% CI 0.28-0.58) for mother-son pairs. We also detected a positive mother-daughter association for BP and positive father-child associations for CRP. CONCLUSION: The statistically significant parent-child association for HbA1c, BP and CRP in Chinese families suggests that household-based interventions could be useful for confronting the high rates of diabetes, hypertension and inflammation in China.

Frequency of alcohol consumption in humans; the role of metabotropic glutamate receptors and downstream signaling pathways.

Rodent models implicate metabotropic glutamate receptors (mGluRs) and downstream signaling pathways in addictive behaviors through metaplasticity. One way mGluRs can influence synaptic plasticity is by regulating the local translation of AMPA receptor trafficking proteins via eukaryotic elongation factor 2 (eEF2). However, genetic variation in this pathway has not been examined with human alcohol use phenotypes. Among a sample of adults living in Detroit, Michigan (Detroit Neighborhood Health Study; n = 788; 83% African American), 206 genetic variants across the mGluR-eEF2-AMPAR pathway (including GRM1, GRM5, HOMER1, HOMER2, EEF2K, MTOR, EIF4E, EEF2, CAMK2A, ARC, GRIA1 and GRIA4) were found to predict number of drinking days per month (corrected P-value < 0.01) when considered as a set (set-based linear regression conducted in PLINK). In addition, a CpG site located in the 3'-untranslated region on the north shore of EEF2 (cg12255298) was hypermethylated in those who drank more frequently (P < 0.05). Importantly, the association between several genetic variants within the mGluR-eEF2-AMPAR pathway and alcohol use behavior (i.e., consumption and alcohol-related problems) replicated in the Grady Trauma Project (GTP), an independent sample of adults living in Atlanta, Georgia (n = 1034; 95% African American), including individual variants in GRM1, GRM5, EEF2, MTOR, GRIA1, GRIA4 and HOMER2 (P < 0.05). Gene-based analyses conducted in the GTP indicated that GRM1 (empirical P < 0.05) and EEF2 (empirical P < 0.01) withstood multiple test corrections and predicted increased alcohol consumption and related problems. In conclusion, insights from rodent studies enabled the identification of novel human alcohol candidate genes within the mGluR-eEF2-AMPAR pathway.

An analysis of 6 decades of hygiene-related advertising: 1940-2000.

OBJECTIVES: To describe and analyze trends in hygiene-related advertisements and examine potential social and regulatory changes that might be associated with these trends. METHODS: From 1940 to 2000, advertisements in January issues of 2 widely read magazines were analyzed every fifth year, and 2 additional magazines only available from 1960 to 2000 were also analyzed every fifth year. In a content analysis, the total number of advertisements were determined and specific advertisements were grouped into categories (personal hygiene, dishwashing, laundry, and house cleaning) and further examined for the presence of 4 key claims (aesthetics, health effects, time-saving, and microbial effects). RESULTS: From 1940 to 2000 for all magazines combined, 10.4% of the advertisements were devoted to hygiene products. After 1960 there were significantly fewer hygiene advertisements as compared with 1940 to 1955, and there was a significant increase after 1980 (P <.00001). Throughout all 6 decades, most advertisements related to personal hygiene. There were no significant differences over time in the proportion of advertisements that made claims related to health, microbial effects, or aesthetics, but significantly more advertisements before 1960 made time-savings claims (P =.009). CONCLUSIONS: This content analysis reflects a cyclical attention in consumer advertising to personal and home hygiene products during the past 6 decades, with a waning of interest in the decades from 1960 to 1980 and an apparent resurgence of advertisements from 1985 to 2000. The potential contributions of federal regulatory bodies and societal changes (e.g., new marketing strategies and options, product development, new and re-emerging infectious diseases, increasing concern about antimicrobial resistance, and increasing recognition that infectious diseases are unlikely to be eradicated) to these marketing trends are discussed.

A comparison of the bacteria found on the hands of 'homemakers' and neonatal intensive care unit nurses.

This prevalence study was conducted to compare the counts, types and antimicrobial resistance profiles of bacterial flora on the hands of individuals in the community to that of nurses at a nearby university teaching hospital, with an intense hand hygiene regimen. Hand cultures were obtained from 204 individuals during a home visit and 119 nurses in two neonatal intensive care units (NICUs). The mean total log counts of organisms were 5.73 and 5.24 for the homemakers [defined as the person (usually the mother) who is the primary person responsible for arranging childcare, cooking, cleaning etc] and nurse hands, respectively (P<0.0001). Significantly more homemakers had Acinetobacter lwoffii, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, P. fluorescens/putida, and Staphylococcus aureus on their hands compared with the nurses (all P<0.05). However, significantly more nurses had Enterococcus faecalis, S. epidermidis, and S. warneri on their hands (P<0.05). Of note, the hands of nurses harboured significantly more S. epidermidis strains resistant to amoxicillin/clavulanate, cefazolin, clindamycin, erythromycin, and oxacillin and S. warneri resistant to amoxicillin/clavulanate, cefazolin, clindamycin, and oxacillin (P<0.05). Surprisingly, significantly more trimethoprim/sulfamethoxazole-resistant S. epidermidis and ciprofloxacin-resistant S. warneri was recovered from the hands of homemakers (P<0.05). This study demonstrates differences in prevalence, bacterial composition and antimicrobial resistance of hand flora of hospital personnel compared with homemakers. Moreover, the hands of homemakers may serve as community reservoirs for antimicrobial resistant strains of clinical importance.

Comparison of different regimens for surgical hand preparation.

Twenty surgical staff members participated in a clinical trial to compare the microbiology and skin condition of hands when using a traditional surgical scrub (TSS) with a detergent-based antiseptic containing 4% chlorhexidine gluconate (CHG) and a short application without scrub of a waterless hand preparation (HP) containing 61% ethyl alcohol, 1% CHG, and emollients. The HP was associated with less skin damage (P = .002) and lower microbial counts postscrub at days five (P = .002) and 19 (P = .02). The HP protocol had shorter contact time (HP mean [M] = 80.7 seconds; TSS M = 144.9 seconds; P < .0001), and more subjects preferred the HP regimen (P = .001). The HP performed better than the TSS, was less costly, and should be evaluated in larger trials and considered for widespread implementation.

Interaction between polygenic risk for cigarette use and environmental exposures in the Detroit Neighborhood Health Study.

Cigarette smoking is influenced both by genetic and environmental factors. Until this year, all large-scale gene identification studies on smoking were conducted in populations of European ancestry. Consequently, the genetic architecture of smoking is not well described in other populations. Further, despite a rich epidemiologic literature focused on the social determinants of smoking, few studies have examined the moderation of genetic influences (for example, gene-environment interactions) on smoking in African Americans. In the Detroit Neighborhood Health Study (DNHS), a sample of randomly selected majority African American residents of Detroit, we constructed a genetic risk score (GRS), in which we combined top (P-value <5 × 10(-7)) genetic variants from a recent meta-analysis conducted in a large sample of African Americans. Using regression (effective n=399), we first tested for association between the GRS and cigarettes per day, attempting to replicate the findings from the meta-analysis. Second, we examined interactions with three social contexts that may moderate the genetic association with smoking: traumatic events, neighborhood social cohesion and neighborhood physical disorder. Among individuals who had ever smoked cigarettes, the GRS significantly predicted the number of cigarettes smoked per day and accounted for ~3% of the overall variance in the trait. Significant interactions were observed between the GRS and number of traumatic events experienced, as well as between the GRS and average neighborhood social cohesion; the association between genetic risk and smoking was greater among individuals who had experienced an increased number of traumatic events in their lifetimes, and diminished among individuals who lived in a neighborhood characterized by greater social cohesion. This study provides support for the utility of the GRS as an alternative approach to replication of common polygenic variation, and in gene-environment interaction, for smoking behaviors. In addition, this study indicates that environmental determinants have the potential to both exacerbate (traumatic events) and diminish (neighborhood social cohesion) genetic influences on smoking behaviors.