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Sample records for epidemiologic methods

  1. Epidemiologic methods in analysis of scientific issues

    NASA Astrophysics Data System (ADS)

    Erdreich, Linda S.

    2003-10-01

    Studies of human populations provide much of the information that is used to evaluate compensation cases for hearing loss, including rates of hearing loss by age, and dose-response relationships. The reference data used to make decisions regarding workman's compensation is based on epidemiologic studies of cohorts of workers exposed to various noise levels. Epidemiology and its methods can be used in other ways in the courtroom; to assess the merits of a complaint, to support Daubert criteria, and to explain scientific issues to the trier of fact, generally a layperson. Using examples other than occupational noise induced hearing loss, these methods will be applied to respond to a complaint that hearing loss followed exposure to a sudden noise, a medication, or an occupational chemical, and thus was caused by said exposure. The standard criteria for assessing the weight of the evidence, and epidemiologic criteria for causality show the limits of such anecdotal data and incorporate quantitative and temporal issues. Reports of clusters of cases are also intuitively convincing to juries. Epidemiologic methods provide a scientific approach to assess whether rates of the outcome are indeed increased, and the extent to which increased rates provide evidence for causality.

  2. Kinetics methods for clinical epidemiology problems.

    PubMed

    Corlan, Alexandru Dan; Ross, John

    2015-11-17

    Calculating the probability of each possible outcome for a patient at any time in the future is currently possible only in the simplest cases: short-term prediction in acute diseases of otherwise healthy persons. This problem is to some extent analogous to predicting the concentrations of species in a reactor when knowing initial concentrations and after examining reaction rates at the individual molecule level. The existing theoretical framework behind predicting contagion and the immediate outcome of acute diseases in previously healthy individuals is largely analogous to deterministic kinetics of chemical systems consisting of one or a few reactions. We show that current statistical models commonly used in chronic disease epidemiology correspond to simple stochastic treatment of single reaction systems. The general problem corresponds to stochastic kinetics of complex reaction systems. We attempt to formulate epidemiologic problems related to chronic diseases in chemical kinetics terms. We review methods that may be adapted for use in epidemiology. We show that some reactions cannot fit into the mass-action law paradigm and solutions to these systems would frequently exhibit an antiportfolio effect. We provide a complete example application of stochastic kinetics modeling for a deductive meta-analysis of two papers on atrial fibrillation incidence, prevalence, and mortality.

  3. Methods of Measurement in epidemiology: Sedentary Behaviour

    PubMed Central

    Atkin, Andrew J; Gorely, Trish; Clemes, Stacy A; Yates, Thomas; Edwardson, Charlotte; Brage, Soren; Salmon, Jo; Marshall, Simon J; Biddle, Stuart JH

    2012-01-01

    Background Research examining sedentary behaviour as a potentially independent risk factor for chronic disease morbidity and mortality has expanded rapidly in recent years. Methods We present a narrative overview of the sedentary behaviour measurement literature. Subjective and objective methods of measuring sedentary behaviour suitable for use in population-based research with children and adults are examined. The validity and reliability of each method is considered, gaps in the literature specific to each method identified and potential future directions discussed. Results To date, subjective approaches to sedentary behaviour measurement, e.g. questionnaires, have focused predominantly on TV viewing or other screen-based behaviours. Typically, such measures demonstrate moderate reliability but slight to moderate validity. Accelerometry is increasingly being used for sedentary behaviour assessments; this approach overcomes some of the limitations of subjective methods, but detection of specific postures and postural changes by this method is somewhat limited. Instruments developed specifically for the assessment of body posture have demonstrated good reliability and validity in the limited research conducted to date. Miniaturization of monitoring devices, interoperability between measurement and communication technologies and advanced analytical approaches are potential avenues for future developments in this field. Conclusions High-quality measurement is essential in all elements of sedentary behaviour epidemiology, from determining associations with health outcomes to the development and evaluation of behaviour change interventions. Sedentary behaviour measurement remains relatively under-developed, although new instruments, both objective and subjective, show considerable promise and warrant further testing. PMID:23045206

  4. An introduction to epidemiologic and statistical methods useful in environmental epidemiology.

    PubMed

    Nitta, Hiroshi; Yamazaki, Shin; Omori, Takashi; Sato, Tosiya

    2010-01-01

    Many developments in the design and analysis of environmental epidemiology have been made in air pollution studies. In the analysis of the short-term effects of particulate matter on daily mortality, Poisson regression models with flexible smoothing methods have been developed for the analysis of time-series data. Another option for such studies is the use of case-crossover designs, and there have been extensive discussions on the selection of control periods. In the Study on Respiratory Disease and Automobile Exhaust project conducted by the Japanese Ministry of the Environment, we adopted a new 2-stage case-control design that is efficient when both exposure and disease are rare. Based on our experience in conducting air pollution epidemiologic studies, we review 2-stage case-control designs, case-crossover designs, generalized linear models, generalized additive models, and generalized estimating equations, all of which are useful approaches in environmental epidemiology.

  5. [Malignant tumours of the eye: Epidemiology, diagnostic methods and radiotherapy].

    PubMed

    Jardel, P; Caujolle, J-P; Gastaud, L; Maschi, C; Sauerwein, W; Thariat, J

    2015-12-01

    Malignant tumours of the eye are not common, barely representing 1 % of all cancers. This article aims to summarise, for each of the main eye malignant diseases, aspects of epidemiology, diagnostic methods and treatments, with a focus on radiation therapy techniques. The studied tumours are: eye metastasis, intraocular and ocular adnexal lymphomas, uveal melanomas, malignant tumours of the conjunctive, of the lids, and retinoblastomas. The last chapter outlines ocular complications of radiation therapy and their management.

  6. Anonymous statistical methods versus cryptographic methods in epidemiology.

    PubMed

    Quantin; Allaert; Dusserre

    2000-11-01

    Sensitive data are most often indirectly identifiable and so need to be rendered anonymous in order to ensure privacy. Statistical methods to provide anonymity require data perturbation and so generate data processing difficulties. Encryption methods, while preserving confidentiality, do not require data modification.

  7. Epidemiology and statistical methods in prediction of patient outcome.

    PubMed

    Bostwick, David G; Adolfsson, Jan; Burke, Harry B; Damber, Jan-Erik; Huland, Hartwig; Pavone-Macaluso, Michele; Waters, David J

    2005-05-01

    Substantial gaps exist in the data of the assessment of risk and prognosis that limit our understanding of the complex mechanisms that contribute to the greatest cancer epidemic, prostate cancer, of our time. This report was prepared by an international multidisciplinary committee of the World Health Organization to address contemporary issues of epidemiology and statistical methods in prostate cancer, including a summary of current risk assessment methods and prognostic factors. Emphasis was placed on the relative merits of each of the statistical methods available. We concluded that: 1. An international committee should be created to guide the assessment and validation of molecular biomarkers. The goal is to achieve more precise identification of those who would benefit from treatment. 2. Prostate cancer is a predictable disease despite its biologic heterogeneity. However, the accuracy of predicting it must be improved. We expect that more precise statistical methods will supplant the current staging system. The simplicity and intuitive ease of using the current staging system must be balanced against the serious compromise in accuracy for the individual patient. 3. The most useful new statistical approaches will integrate molecular biomarkers with existing prognostic factors to predict conditional life expectancy (i.e. the expected remaining years of a patient's life) and take into account all-cause mortality.

  8. Using Epidemiologic Methods to Test Hypotheses regarding Causal Influences on Child and Adolescent Mental Disorders

    ERIC Educational Resources Information Center

    Lahey, Benjamin B.; D'Onofrio, Brian M.; Waldman, Irwin D.

    2009-01-01

    Epidemiology uses strong sampling methods and study designs to test refutable hypotheses regarding the causes of important health, mental health, and social outcomes. Epidemiologic methods are increasingly being used to move developmental psychopathology from studies that catalogue correlates of child and adolescent mental health to designs that…

  9. Has epidemiology become infatuated with methods? A historical perspective on the place of methods during the classical (1945-1965) phase of epidemiology.

    PubMed

    Morabia, Alfredo

    2015-03-18

    Before World War II, epidemiology was a small discipline, practiced by a handful of people working mostly in the United Kingdom and in the United States. Today it is practiced by tens of thousands of people on all continents. Between 1945 and 1965, during what is known as its "classical" phase, epidemiology became recognized as a major academic discipline in medicine and public health. On the basis of a review of the historical evidence, this article examines to which extent classical epidemiology has been a golden age of an action-driven, problem-solving science, in which epidemiologists were less concerned with the sophistication of their methods than with the societal consequences of their work. It also discusses whether the paucity of methods stymied or boosted classical epidemiology's ability to convince political and financial agencies about the need to intervene in order to improve the health of the people.

  10. Bone lead measured by X-ray fluorescence: epidemiologic methods.

    PubMed Central

    Hu, H; Aro, A; Rotnitzky, A

    1995-01-01

    In vivo X-ray fluorescence (XRF) measurement of bone lead concentration (XRF) has emerged as an important technique for future epidemiological studies of long-term toxicity. Several issues germane to epidemiologic methodology need to be addressed, however. First, sources of variability in measurements of bone lead need to be quantified, including imprecision related to the physical measurement itself and the variability of lead deposition over the two main compartments of bones (cortical vs. trabecular) and within each compartment. Imprecision related to the physical measurement can be estimated for each individual measurement based on the variability of the signal and background. Second, approaches to low-level data need to be debated. We argue for using the minimal detection limit (MDL) to compare instruments and interpret individual measurements; however, with regard to epidemiologic studies, we would abandon the MDL in favor of using all point estimates. In analyses using bone lead as an independent variable, statistical techniques can be used to adjust regression estimates based on estimates of measurement uncertainty and bone lead variability. Third, factors that can be expected to modify the relationship between bone lead and toxicity such as gravida history, endocrinological states, nutrition, and other important influences on bone metabolism, need to be identified and measured in epidemiologic studies. By addressing these issues, investigators will be able to maximize the utility of XRF measurements in environmental epidemiologic studies. Images Figure 2. PMID:7621788

  11. [An analysis to the focus of (American Journal of Epidemiology) research with bibliometrics methods].

    PubMed

    Cui, L

    1996-06-01

    Using bibliometric method, the author counted the citation of papers published in American Journal of Epidemiology in the last 3 years. The highly cited papers and books were presented and the focus of recent years on American Journal of Epidemiology outlined.

  12. The ZInEP Epidemiology Survey: background, design and methods.

    PubMed

    Ajdacic-Gross, Vladeta; Müller, Mario; Rodgers, Stephanie; Warnke, Inge; Hengartner, Michael P; Landolt, Karin; Hagenmuller, Florence; Meier, Magali; Tse, Lee-Ting; Aleksandrowicz, Aleksandra; Passardi, Marco; Knöpfli, Daniel; Schönfelder, Herdis; Eisele, Jochen; Rüsch, Nicolas; Haker, Helene; Kawohl, Wolfram; Rössler, Wulf

    2014-12-01

    This article introduces the design, sampling, field procedures and instruments used in the ZInEP Epidemiology Survey. This survey is one of six ZInEP projects (Zürcher Impulsprogramm zur nachhaltigen Entwicklung der Psychiatrie, i.e. the "Zurich Program for Sustainable Development of Mental Health Services"). It parallels the longitudinal Zurich Study with a sample comparable in age and gender, and with similar methodology, including identical instruments. Thus, it is aimed at assessing the change of prevalence rates of common mental disorders and the use of professional help and psychiatric sevices. Moreover, the current survey widens the spectrum of topics by including sociopsychiatric questionnaires on stigma, stress related biological measures such as load and cortisol levels, electroencephalographic (EEG) and near-infrared spectroscopy (NIRS) examinations with various paradigms, and sociophysiological tests. The structure of the ZInEP Epidemiology Survey entails four subprojects: a short telephone screening using the SCL-27 (n of nearly 10,000), a comprehensive face-to-face interview based on the SPIKE (Structured Psychopathological Interview and Rating of the Social Consequences for Epidemiology: the main instrument of the Zurich Study) with a stratified sample (n = 1500), tests in the Center for Neurophysiology and Sociophysiology (n = 227), and a prospective study with up to three follow-up interviews and further measures (n = 157). In sum, the four subprojects of the ZInEP Epidemiology Survey deliver a large interdisciplinary database.

  13. The role of applied epidemiology methods in the disaster management cycle.

    PubMed

    Malilay, Josephine; Heumann, Michael; Perrotta, Dennis; Wolkin, Amy F; Schnall, Amy H; Podgornik, Michelle N; Cruz, Miguel A; Horney, Jennifer A; Zane, David; Roisman, Rachel; Greenspan, Joel R; Thoroughman, Doug; Anderson, Henry A; Wells, Eden V; Simms, Erin F

    2014-11-01

    Disaster epidemiology (i.e., applied epidemiology in disaster settings) presents a source of reliable and actionable information for decision-makers and stakeholders in the disaster management cycle. However, epidemiological methods have yet to be routinely integrated into disaster response and fully communicated to response leaders. We present a framework consisting of rapid needs assessments, health surveillance, tracking and registries, and epidemiological investigations, including risk factor and health outcome studies and evaluation of interventions, which can be practiced throughout the cycle. Applying each method can result in actionable information for planners and decision-makers responsible for preparedness, response, and recovery. Disaster epidemiology, once integrated into the disaster management cycle, can provide the evidence base to inform and enhance response capability within the public health infrastructure.

  14. The Role of Applied Epidemiology Methods in the Disaster Management Cycle

    PubMed Central

    Heumann, Michael; Perrotta, Dennis; Wolkin, Amy F.; Schnall, Amy H.; Podgornik, Michelle N.; Cruz, Miguel A.; Horney, Jennifer A.; Zane, David; Roisman, Rachel; Greenspan, Joel R.; Thoroughman, Doug; Anderson, Henry A.; Wells, Eden V.; Simms, Erin F.

    2014-01-01

    Disaster epidemiology (i.e., applied epidemiology in disaster settings) presents a source of reliable and actionable information for decision-makers and stakeholders in the disaster management cycle. However, epidemiological methods have yet to be routinely integrated into disaster response and fully communicated to response leaders. We present a framework consisting of rapid needs assessments, health surveillance, tracking and registries, and epidemiological investigations, including risk factor and health outcome studies and evaluation of interventions, which can be practiced throughout the cycle. Applying each method can result in actionable information for planners and decision-makers responsible for preparedness, response, and recovery. Disaster epidemiology, once integrated into the disaster management cycle, can provide the evidence base to inform and enhance response capability within the public health infrastructure. PMID:25211748

  15. Trends in epidemiology in the 21st century: time to adopt Bayesian methods.

    PubMed

    Martinez, Edson Zangiacomi; Achcar, Jorge Alberto

    2014-04-01

    2013 marked the 250th anniversary of the presentation of Bayes' theorem by the philosopher Richard Price. Thomas Bayes was a figure little known in his own time, but in the 20th century the theorem that bears his name became widely used in many fields of research. The Bayes theorem is the basis of the so-called Bayesian methods, an approach to statistical inference that allows studies to incorporate prior knowledge about relevant data characteristics into statistical analysis. Nowadays, Bayesian methods are widely used in many different areas such as astronomy, economics, marketing, genetics, bioinformatics and social sciences. This study observed that a number of authors discussed recent advances in techniques and the advantages of Bayesian methods for the analysis of epidemiological data. This article presents an overview of Bayesian methods, their application to epidemiological research and the main areas of epidemiology which should benefit from the use of Bayesian methods in coming years.

  16. Concordance and discordance of sequence survey methods for molecular epidemiology

    PubMed Central

    Hasan, Nur A.; Cebula, Thomas A.; Colwell, Rita R.; Robison, Richard A.; Johnson, W. Evan; Crandall, Keith A.

    2015-01-01

    The post-genomic era is characterized by the direct acquisition and analysis of genomic data with many applications, including the enhancement of the understanding of microbial epidemiology and pathology. However, there are a number of molecular approaches to survey pathogen diversity, and the impact of these different approaches on parameter estimation and inference are not entirely clear. We sequenced whole genomes of bacterial pathogens, Burkholderia pseudomallei, Yersinia pestis, and Brucella spp. (60 new genomes), and combined them with 55 genomes from GenBank to address how different molecular survey approaches (whole genomes, SNPs, and MLST) impact downstream inferences on molecular evolutionary parameters, evolutionary relationships, and trait character associations. We selected isolates for sequencing to represent temporal, geographic origin, and host range variability. We found that substitution rate estimates vary widely among approaches, and that SNP and genomic datasets yielded different but strongly supported phylogenies. MLST yielded poorly supported phylogenies, especially in our low diversity dataset, i.e., Y. pestis. Trait associations showed that B. pseudomallei and Y. pestis phylogenies are significantly associated with geography, irrespective of the molecular survey approach used, while Brucella spp. phylogeny appears to be strongly associated with geography and host origin. We contrast inferences made among monomorphic (clonal) and non-monomorphic bacteria, and between intra- and inter-specific datasets. We also discuss our results in light of underlying assumptions of different approaches. PMID:25737810

  17. Influence of DNA extraction methods on relative telomere length measurements and its impact on epidemiological studies

    PubMed Central

    Raschenberger, Julia; Lamina, Claudia; Haun, Margot; Kollerits, Barbara; Coassin, Stefan; Boes, Eva; Kedenko, Ludmilla; Köttgen, Anna; Kronenberg, Florian

    2016-01-01

    Measurement of telomere length is widely used in epidemiologic studies. Insufficient standardization of the measurements processes has, however, complicated the comparison of results between studies. We aimed to investigate whether DNA extraction methods have an influence on measured values of relative telomere length (RTL) and whether this has consequences for epidemiological studies. We performed four experiments with RTL measurement in quadruplicate by qPCR using DNA extracted with different methods: 1) a standardized validation experiment including three extraction methods (magnetic-particle-method EZ1, salting-out-method INV, phenol-chloroform-isoamyl-alcohol PCI) each in the same 20 samples demonstrated pronounced differences in RTL with lowest values with EZ1 followed by INV and PCI-isolated DNA; 2) a comparison of 307 samples from an epidemiological study showing EZ1-measurements 40% lower than INV-measurements; 3) a matching-approach of two similar non-diseased control groups including 143 pairs of subjects revealed significantly shorter RTL in EZ1 than INV-extracted DNA (0.844 ± 0.157 vs. 1.357 ± 0.242); 4) an association analysis of RTL with prevalent cardiovascular disease detected a stronger association with INV than with EZ1-extracted DNA. In summary, DNA extraction methods have a pronounced influence on the measured RTL-values. This might result in spurious or lost associations in epidemiological studies under certain circumstances. PMID:27138987

  18. Influence of DNA extraction methods on relative telomere length measurements and its impact on epidemiological studies.

    PubMed

    Raschenberger, Julia; Lamina, Claudia; Haun, Margot; Kollerits, Barbara; Coassin, Stefan; Boes, Eva; Kedenko, Ludmilla; Köttgen, Anna; Kronenberg, Florian

    2016-05-03

    Measurement of telomere length is widely used in epidemiologic studies. Insufficient standardization of the measurements processes has, however, complicated the comparison of results between studies. We aimed to investigate whether DNA extraction methods have an influence on measured values of relative telomere length (RTL) and whether this has consequences for epidemiological studies. We performed four experiments with RTL measurement in quadruplicate by qPCR using DNA extracted with different methods: 1) a standardized validation experiment including three extraction methods (magnetic-particle-method EZ1, salting-out-method INV, phenol-chloroform-isoamyl-alcohol PCI) each in the same 20 samples demonstrated pronounced differences in RTL with lowest values with EZ1 followed by INV and PCI-isolated DNA; 2) a comparison of 307 samples from an epidemiological study showing EZ1-measurements 40% lower than INV-measurements; 3) a matching-approach of two similar non-diseased control groups including 143 pairs of subjects revealed significantly shorter RTL in EZ1 than INV-extracted DNA (0.844 ± 0.157 vs. 1.357 ± 0.242); 4) an association analysis of RTL with prevalent cardiovascular disease detected a stronger association with INV than with EZ1-extracted DNA. In summary, DNA extraction methods have a pronounced influence on the measured RTL-values. This might result in spurious or lost associations in epidemiological studies under certain circumstances.

  19. Trends in Citations to Books on Epidemiological and Statistical Methods in the Biomedical Literature

    PubMed Central

    Porta, Miquel; Vandenbroucke, Jan P.; Ioannidis, John P. A.; Sanz, Sergio; Fernandez, Esteve; Bhopal, Raj; Morabia, Alfredo; Victora, Cesar; Lopez, Tomàs

    2013-01-01

    Background There are no analyses of citations to books on epidemiological and statistical methods in the biomedical literature. Such analyses may shed light on how concepts and methods changed while biomedical research evolved. Our aim was to analyze the number and time trends of citations received from biomedical articles by books on epidemiological and statistical methods, and related disciplines. Methods and Findings The data source was the Web of Science. The study books were published between 1957 and 2010. The first year of publication of the citing articles was 1945. We identified 125 books that received at least 25 citations. Books first published in 1980–1989 had the highest total and median number of citations per year. Nine of the 10 most cited texts focused on statistical methods. Hosmer & Lemeshow's Applied logistic regression received the highest number of citations and highest average annual rate. It was followed by books by Fleiss, Armitage, et al., Rothman, et al., and Kalbfleisch and Prentice. Fifth in citations per year was Sackett, et al., Evidence-based medicine. The rise of multivariate methods, clinical epidemiology, or nutritional epidemiology was reflected in the citation trends. Educational textbooks, practice-oriented books, books on epidemiological substantive knowledge, and on theory and health policies were much less cited. None of the 25 top-cited books had the theoretical or sociopolitical scope of works by Cochrane, McKeown, Rose, or Morris. Conclusions Books were mainly cited to reference methods. Books first published in the 1980s continue to be most influential. Older books on theory and policies were rooted in societal and general medical concerns, while the most modern books are almost purely on methods. PMID:23667447

  20. [Mendelian randomisation - a genetic approach to an epidemiological method].

    PubMed

    Stensrud, Mats Julius

    2016-06-01

    BACKGROUND Genetic information is becoming more easily available, and rapid progress is being made in developing methods of illuminating issues of interest. Mendelian randomisation makes it possible to study causes of disease using observational data. The name refers to the random distribution of gene variants in meiosis. The methodology makes use of genes that influence a risk factor for a disease, without influencing the disease itself. In this review article I explain the principles behind Mendelian randomisation and present the areas of application for this methodology.MATERIAL AND METHOD Methodology articles describing Mendelian randomisation were reviewed. The articles were found through a search in PubMed with the combination «mendelian randomization» OR «mendelian randomisation», and a search in McMaster Plus with the combination «mendelian randomization». A total of 15 methodology articles were read in full text. Methodology articles were supplemented by clinical studies found in the PubMed search.RESULTS In contrast to traditional observational studies, Mendelian randomisation studies are not affected by two important sources of error: conventional confounding variables and reverse causation. Mendelian randomisation is therefore a promising tool for studying causality. Mendelian randomisation studies have already provided valuable knowledge on the risk factors for a wide range of diseases. It is nevertheless important to be aware of the limitations of the methodology. As a result of the rapid developments in genetics research, Mendelian randomisation will probably be widely used in future years.INTERPRETATION If Mendelian randomisation studies are conducted correctly, they may help to reveal both modifiable and non-modifiable causes of disease.

  1. Violent crime in San Antonio, Texas: an application of spatial epidemiological methods.

    PubMed

    Sparks, Corey S

    2011-12-01

    Violent crimes are rarely considered a public health problem or investigated using epidemiological methods. But patterns of violent crime and other health conditions are often affected by similar characteristics of the built environment. In this paper, methods and perspectives from spatial epidemiology are used in an analysis of violent crimes in San Antonio, TX. Bayesian statistical methods are used to examine the contextual influence of several aspects of the built environment. Additionally, spatial regression models using Bayesian model specifications are used to examine spatial patterns of violent crime risk. Results indicate that the determinants of violent crime depend on the model specification, but are primarily related to the built environment and neighborhood socioeconomic conditions. Results are discussed within the context of a rapidly growing urban area with a diverse population.

  2. Comparing Two Epidemiologic Surveillance Methods to Assess Underestimation of Human Stampedes in India

    PubMed Central

    Ngai, Ka Ming; Lee, Wing Yan; Madan, Aditi; Sanyal, Saswata; Roy, Nobhojit; Burkle, Frederick M.; Hsu, Edbert B.

    2013-01-01

    Background: Two separate but complementary epidemiologic surveillance methods for human stampedes have emerged since the publication of the topic in 2009. The objective of this study is to estimate the degree of underreporting in India. Method: The Ngai Search Method was compared to the Roy Search Method for human stampede events occurring in India between 2001 and 2010. Results: A total of 40 stampedes were identified by both search methods. Using the Ngai method, 34 human stampedes were identified. Using a previously defined stampede scale: 2 events were class I, 21 events were class II, 8 events were class III, and 3 events were class IV. The median deaths were 5.5 per event and median injuries were 13.5 per event. Using the Roy method, 27 events were identified, including 9 events that were not identified by the Ngai method. After excluding events based on exclusion criteria, six additional events identified by the Roy’s method had a median of 4 deaths and 30 injuries. In multivariate analysis using the Ngai method, religious (6.52, 95%CI 1.73-24.66, p=0.006) and political (277.09, 95%CI 5.12-15,001.96, p=0.006) events had higher relative number of deaths. Conclusion: Many causes accounting for the global increase in human stampede events can only be elucidated through systematic epidemiological investigation. Focusing on a country with a high recurrence of human stampedes, we compare two independent methods of data abstraction in an effort to improve the existing database and to identify pertinent risk factors. We concluded that our previous publication underestimated stampede events in India by approximately 18% and an international standardized database to systematically record occurrence of human stampedes is needed to facilitate understanding of the epidemiology of human stampedes. PMID:24077300

  3. An internet-based method of selecting control populations for epidemiologic studies.

    PubMed

    Stone, Mary Bishop; Lyon, Joseph L; Simonsen, Sara Ellis; White, George L; Alder, Stephen C

    2007-01-01

    Identifying control subjects for epidemiologic studies continues to increase in difficulty because of changes in telephone technology such as answering services and machines, caller identification, and cell phones. An Internet-based method for obtaining study subjects that may increase response rates has been developed and is described. This method uses information from two websites that, when combined, provide accurate and complete lists of names, addresses, and listed phone numbers. This method was developed by use of randomly selected streets in a suburb of Salt Lake City, Utah, in June 2005.

  4. [Methodical reflections on epidemiological methods to measure adverse medical device events].

    PubMed

    Lessing, C

    2009-06-01

    Drugs and medical devices are common remedies in patient care. Concerning patient safety, much research has been undertaken to study medication-related events, such as adverse drug events or medication errors; however, only little is known about device-related events and patient safety. Until now, only one survey on the epidemiology of adverse medical device events has been published. Estimates amount to 8.4 adverse medical device events/100 hospitalizations. As this indicates, further research is needed on epidemiological methodology to investigate the frequency, distribution, causes and results of medical device-related events. Only profound knowledge will constitute a resilient base for the development of safety strategies which can be then implemented and evaluated. Also in the German health care system, the special challenges described for data collection have to be mastered.

  5. Methods for measuring utilization of mental health services in two epidemiologic studies

    PubMed Central

    NOVINS, DOUGLAS K.; BEALS, JANETTE; CROY, CALVIN; MANSON, SPERO M.

    2015-01-01

    Objectives of Study Psychiatric epidemiologic studies often include two or more sets of questions regarding service utilization, but the agreement across these different questions and the factors associated with their endorsement have not been examined. The objectives of this study were to describe the agreement of different sets of mental health service utilization questions that were included in the American Indian Service Utilization Psychiatric Epidemiology Risk and Protective Factors Project (AI-SUPERPFP), and compare the results to similar questions included in the baseline National Comorbidity Survey (NCS). Methods Responses to service utilization questions by 2878 AI-SUPERPFP and 5877 NCS participants were examined by calculating estimates of service use and agreement (κ) across the different sets of questions. Logistic regression models were developed to identify factors associated with endorsement of specific sets of questions. Results In both studies, estimates of mental health service utilization varied across the different sets of questions. Agreement across the different question sets was marginal to good (κ = 0.27–0.69). Characteristics of identified service users varied across the question sets. Limitations Neither survey included data to examine the validity of participant responses to service utilization questions. Recommendations for Further Research Question wording and placement appear to impact estimates of service utilization in psychiatric epidemiologic studies. Given the importance of these estimates for policy-making, further research into the validity of survey responses as well as impacts of question wording and context on rates of service utilization is warranted. PMID:18767205

  6. A survey of variable selection methods in two Chinese epidemiology journals

    PubMed Central

    2010-01-01

    Background Although much has been written on developing better procedures for variable selection, there is little research on how it is practiced in actual studies. This review surveys the variable selection methods reported in two high-ranking Chinese epidemiology journals. Methods Articles published in 2004, 2006, and 2008 in the Chinese Journal of Epidemiology and the Chinese Journal of Preventive Medicine were reviewed. Five categories of methods were identified whereby variables were selected using: A - bivariate analyses; B - multivariable analysis; e.g. stepwise or individual significance testing of model coefficients; C - first bivariate analyses, followed by multivariable analysis; D - bivariate analyses or multivariable analysis; and E - other criteria like prior knowledge or personal judgment. Results Among the 287 articles that reported using variable selection methods, 6%, 26%, 30%, 21%, and 17% were in categories A through E, respectively. One hundred sixty-three studies selected variables using bivariate analyses, 80% (130/163) via multiple significance testing at the 5% alpha-level. Of the 219 multivariable analyses, 97 (44%) used stepwise procedures, 89 (41%) tested individual regression coefficients, but 33 (15%) did not mention how variables were selected. Sixty percent (58/97) of the stepwise routines also did not specify the algorithm and/or significance levels. Conclusions The variable selection methods reported in the two journals were limited in variety, and details were often missing. Many studies still relied on problematic techniques like stepwise procedures and/or multiple testing of bivariate associations at the 0.05 alpha-level. These deficiencies should be rectified to safeguard the scientific validity of articles published in Chinese epidemiology journals. PMID:20920252

  7. New Saliva DNA Collection Method Compared to Buccal Cell Collection Techniques for Epidemiological Studies

    PubMed Central

    ROGERS, NIKKI L.; COLE, SHELLEY A.; LAN, HAO-CHANG; CROSSA, ALDO; DEMERATH, ELLEN W.

    2009-01-01

    Epidemiological studies may require noninvasive methods for off-site DNA collection. We compared the DNA yield and quality obtained using a whole-saliva collection device (Oragene™ DNA collection kit) to those from three established noninvasive methods (cytobrush, foam swab, and oral rinse). Each method was tested on 17 adult volunteers from our center, using a random crossover collection design and analyzed using repeated-measures statistics. DNA yield and quality were assessed via gel electrophoresis, spectophotometry, and polymerase chain reaction (PCR) amplification rate. The whole-saliva method provided a significantly greater DNA yield (mean ± SD = 154.9 ± 103.05 μg, median = 181.88) than the other methods (oral rinse = 54.74 ± 41.72 μg, 36.56; swab = 11.44 ± 7.39 μg, 10.72; cytobrush = 12.66 ± 6.19, 13.22 μg) (all pairwise P < 0.05). Oral-rinse and whole-saliva samples provided the best DNA quality, whereas cytobrush and swab samples provided poorer quality DNA, as shown by lower OD260/OD280 and OD260/OD230 ratios. We conclude that both a 10-ml oral-rinse sample and 2-ml whole-saliva sample provide sufficient DNA quantity and better quality DNA for genetic epidemiological studies than do the commonly used buccal swab and brush techniques. PMID:17421001

  8. New saliva DNA collection method compared to buccal cell collection techniques for epidemiological studies.

    PubMed

    Rogers, Nikki L; Cole, Shelley A; Lan, Hao-Chang; Crossa, Aldo; Demerath, Ellen W

    2007-01-01

    Epidemiological studies may require noninvasive methods for off-site DNA collection. We compared the DNA yield and quality obtained using a whole-saliva collection device (Oragene DNA collection kit) to those from three established noninvasive methods (cytobrush, foam swab, and oral rinse). Each method was tested on 17 adult volunteers from our center, using a random crossover collection design and analyzed using repeated-measures statistics. DNA yield and quality were assessed via gel electrophoresis, spectophotometry, and polymerase chain reaction (PCR) amplification rate. The whole-saliva method provided a significantly greater DNA yield (mean +/- SD = 154.9 +/- 103.05 microg, median = 181.88) than the other methods (oral rinse = 54.74 +/- 41.72 microg, 36.56; swab = 11.44 +/- 7.39 microg, 10.72; cytobrush = 12.66 +/- 6.19, 13.22 microg) (all pairwise P < 0.05). Oral-rinse and whole-saliva samples provided the best DNA quality, whereas cytobrush and swab samples provided poorer quality DNA, as shown by lower OD(260)/OD(280) and OD(260)/OD(230) ratios. We conclude that both a 10-ml oral-rinse sample and 2-ml whole-saliva sample provide sufficient DNA quantity and better quality DNA for genetic epidemiological studies than do the commonly used buccal swab and brush techniques.

  9. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation

    PubMed Central

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2–90.8% and 83.3–86.9% and a specificity of 97.7–98.8% and 95.1–97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values. PMID:26904678

  10. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation.

    PubMed

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2-90.8% and 83.3-86.9% and a specificity of 97.7-98.8% and 95.1-97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values.

  11. A practical method for use in epidemiological studies on enamel hypomineralisation.

    PubMed

    Ghanim, A; Elfrink, M; Weerheijm, K; Mariño, R; Manton, D

    2015-06-01

    With the development of the European Academy of Paediatric Dentistry (EAPD) judgment criteria, there has been increasing interest worldwide in investigation of the prevalence of demarcated opacities in tooth enamel substance, known as molar-incisor hypomineralisation (MIH). However, the lack of a standardised system for the purpose of recording MIH data in epidemiological surveys has contributed greatly to the wide variations in the reported prevalence between studies. The present publication describes the rationale, development, and content of a scoring method for MIH diagnosis in epidemiological studies as well as clinic- and hospital-based studies. The proposed grading method allows separate classification of demarcated hypomineralisation lesions and other enamel defects identical to MIH. It yields an informative description of the severity of MIH-affected teeth in terms of the stage of visible enamel destruction and the area of tooth surface affected (i.e. lesion clinical status and extent, respectively). In order to preserve the maximum amount of information from a clinical examination consistent with the need to permit direct comparisons between prevalence studies, two forms of the charting are proposed, a short form for simple screening surveys and a long form desirable for prospective, longitudinal observational research where aetiological factors in demarcated lesions are to be investigated in tandem with lesions distribution. Validation of the grading method is required, and its reliability and usefulness need to be tested in different age groups and different populations.

  12. Quantitative methods in the tuberculosis epidemiology and in the evaluation of BCG vaccination programs.

    PubMed

    Lugosi, L

    1986-01-01

    Controversies concerning the protective efficacy of the BCG vaccination result mostly from the fact that quantitative methods have not been used in the evaluation of the BCG programs. Therefore, to eliminate the current controversy an unconditional requirement is to apply valid biostatistical models to analyse the results of the BCG programs. In order to achieve objective statistical inferences and epidemiological interpretations the following conditions should be fulfilled: data for evaluation have to be taken from epidemiological trials exempt from sampling error, since the morbidity rates are not normally distributed an appropriate normalizing transformation is needed for point and confidence interval estimations, only unbiased point estimates (dependent variables) could be used in valid models for hypothesis tests, in cases of rejected null hypothesis the ranked estimates of the compared groups must be evaluated in a multiple comparison model in order to diminish the Type I error in the decision. The following quantitative methods are presented to evaluate the effectiveness of BCG vaccination in Hungary: linear regression analysis, stepwise regression analysis and log-linear analysis.

  13. Comparison of Methods to Account for Implausible Reporting of Energy Intake in Epidemiologic Studies

    PubMed Central

    Rhee, Jinnie J.; Sampson, Laura; Cho, Eunyoung; Hughes, Michael D.; Hu, Frank B.; Willett, Walter C.

    2015-01-01

    In a recent article in the American Journal of Epidemiology by Mendez et al. (Am J Epidemiol. 2011;173(4):448–458), the use of alternative approaches to the exclusion of implausible energy intakes led to significantly different cross-sectional associations between diet and body mass index (BMI), whereas the use of a simpler recommended criteria (<500 and >3,500 kcal/day) yielded no meaningful change. However, these findings might have been due to exclusions made based on weight, a primary determinant of BMI. Using data from 52,110 women in the Nurses' Health Study (1990), we reproduced the cross-sectional findings of Mendez et al. and compared the results from the recommended method with those from 2 weight-dependent alternative methods (the Goldberg method and predicted total energy expenditure method). The same 3 exclusion criteria were then used to examine dietary variables prospectively in relation to change in BMI, which is not a direct function of attained weight. We found similar associations using the 3 methods. In a separate cross-sectional analysis using biomarkers of dietary factors, we found similar correlations for intakes of fatty acids (n = 439) and carotenoids and retinol (n = 1,293) using the 3 methods for exclusions. These results do not support the general conclusion that use of exclusion criteria based on the alternative methods might confer an advantage over the recommended exclusion method. PMID:25656533

  14. Development of the residential case-specular epidemiologic investigation method. Final report

    SciTech Connect

    Zaffanella, L.E.; Savitz, D.A.

    1995-11-01

    The residential case-specular method is an innovative approach to epidemiologic studies of the association between wire codes and childhood cancer. This project was designed to further the development of the residential case-specular method, which seeks to help resolve the ``wire code paradox``. For years, wire codes have been used as surrogate measures of past electric and magnetic field (EMF) exposure. There is a magnetic field hypothesis that suggests childhood cancer is associated with exposure to magnetic fields, with wire codes as a proxy for these fields. The neighborhood hypothesis suggests that childhood cancer is associated with neighborhood characteristics and exposures other than magnetic fields, with wire codes as a proxy for these characteristics and exposures. The residential case-specular method was designed to discriminate between the magnetic field and the neighborhood hypothesis. Two methods were developed for determining the specular of a residence. These methods were tested with 400 randomly selected residences. The main advantage of the residential case-specular method is that it may efficiently confirm or eliminate the suspicion that control selection bias or confounding by neighborhood factors affected the results of case-control studies of childhood cancer and magnetic fields. The method may be applicable to both past and ongoing studies. The main disadvantage is that the method is untried. Consequently, further work is required to verify its validity and to ensure that sufficient statistical power can be obtained in a cost-effective manner.

  15. Comparison of methods to account for implausible reporting of energy intake in epidemiologic studies.

    PubMed

    Rhee, Jinnie J; Sampson, Laura; Cho, Eunyoung; Hughes, Michael D; Hu, Frank B; Willett, Walter C

    2015-02-15

    In a recent article in the American Journal of Epidemiology by Mendez et al. (Am J Epidemiol. 2011;173(4):448-458), the use of alternative approaches to the exclusion of implausible energy intakes led to significantly different cross-sectional associations between diet and body mass index (BMI), whereas the use of a simpler recommended criteria (<500 and >3,500 kcal/day) yielded no meaningful change. However, these findings might have been due to exclusions made based on weight, a primary determinant of BMI. Using data from 52,110 women in the Nurses' Health Study (1990), we reproduced the cross-sectional findings of Mendez et al. and compared the results from the recommended method with those from 2 weight-dependent alternative methods (the Goldberg method and predicted total energy expenditure method). The same 3 exclusion criteria were then used to examine dietary variables prospectively in relation to change in BMI, which is not a direct function of attained weight. We found similar associations using the 3 methods. In a separate cross-sectional analysis using biomarkers of dietary factors, we found similar correlations for intakes of fatty acids (n = 439) and carotenoids and retinol (n = 1,293) using the 3 methods for exclusions. These results do not support the general conclusion that use of exclusion criteria based on the alternative methods might confer an advantage over the recommended exclusion method.

  16. Reporting of occupational and environmental research: use and misuse of statistical and epidemiological methods

    PubMed Central

    Rushton, L.

    2000-01-01

    OBJECTIVES—To report some of the most serious omissions and errors which may occur in papers submitted to Occupational and Environmental Medicine, and to give guidelines on the essential components that should be included in papers reporting results from studies of occupational and environmental health.
METHODS—Since 1994 Occupational and Environmental Medicine has used a panel of medical statisticians to review submitted papers which have a substantial statistical content. Although some studies may have genuine errors in their design, execution, and analysis, many of the problems identified during the reviewing process are due to inadequate and incomplete reporting of essential aspects of a study. This paper outlines some of the most important errors and omissions that may occur. Observational studies are often the preferred choice of design in occupational and environmental medicine. Some of the issues relating to design, execution, and analysis which should be considered when reporting three of the most common observational study designs, cross sectional, case-control, and cohort are described. An illustration of good reporting practice is given for each. Various mathematical modelling techniques are often used in the analysis of these studies, the reporting of which causes a major problem to some authors. Suggestions for the presentation of results from modelling are made.
CONCLUSIONS—There is increasing interest in the development and application of formal "good epidemiology practices". These not only consider issues of data quality, study design, and study conduct, but through their structured approach to the documentation of the study procedures, provide the potential for more rigorous reporting of the results in the scientific literature.


Keywords: research reporting; statistical methods; epidemiological methods PMID:10711263

  17. A robust method for iodine status determination in epidemiological studies by capillary electrophoresis.

    PubMed

    de Macedo, Adriana Nori; Teo, Koon; Mente, Andrew; McQueen, Matthew J; Zeidler, Johannes; Poirier, Paul; Lear, Scott A; Wielgosz, Andy; Britz-McKibbin, Philip

    2014-10-21

    Iodine deficiency is the most common preventable cause of intellectual disabilities in children. Global health initiatives to ensure optimum nutrition thus require continuous monitoring of population-wide iodine intake as determined by urinary excretion of iodide. Current methods to analyze urinary iodide are limited by complicated sample pretreatment, costly infrastructure, and/or poor selectivity, posing restrictions to large-scale epidemiological studies. We describe a simple yet selective method to analyze iodide in volume-restricted human urine specimens stored in biorepositories by capillary electrophoresis (CE) with UV detection. Excellent selectivity is achieved when using an acidic background electrolyte in conjunction with dynamic complexation via α-cyclodextrin in an unmodified fused-silica capillary under reversed polarity. Sample self-stacking is developed as a novel online sample preconcentration method to boost sensitivity with submicromolar detection limits for iodide (S/N ≈ 3, 0.06 μM) directly in urine. This assay also allows for simultaneous analysis of environmental iodide uptake inhibitors, including thiocyanate and nitrate. Rigorous method validation confirmed good linearity (R(2) = 0.9998), dynamic range (0.20 to 4.0 μM), accuracy (average recovery of 93% at three concentration levels) and precision for reliable iodide determination in pooled urine specimens over 29 days of analysis (RSD = 11%, n = 87).

  18. Evaluation and validity of a polymerase chain reaction-based open reading frame typing method to dissect the molecular epidemiology for Acinetobacter baumannii in an epidemiologic study of a hospital outbreak.

    PubMed

    Fujikura, Yuji; Yuki, Atsushi; Hamamoto, Takaaki; Ichimura, Sadahiro; Kawana, Akihiko; Ohkusu, Kiyofumi; Matsumoto, Tetsuya

    2016-11-01

    Acinetobacter baumannii is regarded as one of the most important pathogens in hospital outbreaks. To obtain an efficient and simple epidemiologic method of surveillance during outbreaks, we assessed the applicability of the polymerase chain reaction-based open reading frames typing (POT) method and compared it with pulsed-field gel electrophoresis. The POT method was found to have sufficient discriminatory power to identify the strains and would be widely applicable to epidemiologic surveillance during hospital outbreaks.

  19. Imputation method for lifetime exposure assessment in air pollution epidemiologic studies

    PubMed Central

    2013-01-01

    Background Environmental epidemiology, when focused on the life course of exposure to a specific pollutant, requires historical exposure estimates that are difficult to obtain for the full time period due to gaps in the historical record, especially in earlier years. We show that these gaps can be filled by applying multiple imputation methods to a formal risk equation that incorporates lifetime exposure. We also address challenges that arise, including choice of imputation method, potential bias in regression coefficients, and uncertainty in age-at-exposure sensitivities. Methods During time periods when parameters needed in the risk equation are missing for an individual, the parameters are filled by an imputation model using group level information or interpolation. A random component is added to match the variance found in the estimates for study subjects not needing imputation. The process is repeated to obtain multiple data sets, whose regressions against health data can be combined statistically to develop confidence limits using Rubin’s rules to account for the uncertainty introduced by the imputations. To test for possible recall bias between cases and controls, which can occur when historical residence location is obtained by interview, and which can lead to misclassification of imputed exposure by disease status, we introduce an “incompleteness index,” equal to the percentage of dose imputed (PDI) for a subject. “Effective doses” can be computed using different functional dependencies of relative risk on age of exposure, allowing intercomparison of different risk models. To illustrate our approach, we quantify lifetime exposure (dose) from traffic air pollution in an established case–control study on Long Island, New York, where considerable in-migration occurred over a period of many decades. Results The major result is the described approach to imputation. The illustrative example revealed potential recall bias, suggesting that regressions

  20. Optical fingerprinting in bacterial epidemiology: Raman spectroscopy as a real-time typing method.

    PubMed

    Willemse-Erix, Diana F M; Scholtes-Timmerman, Maarten J; Jachtenberg, Jan-Willem; van Leeuwen, Willem B; Horst-Kreft, Deborah; Bakker Schut, Tom C; Deurenberg, Ruud H; Puppels, Gerwin J; van Belkum, Alex; Vos, Margreet C; Maquelin, Kees

    2009-03-01

    Hospital-acquired infections (HAI) increase morbidity and mortality and constitute a high financial burden on health care systems. An effective weapon against HAI is early detection of potential outbreaks and sources of contamination. Such monitoring requires microbial typing with sufficient reproducibility and discriminatory power. Here, a microbial-typing method is presented, based on Raman spectroscopy. This technique provides strain-specific optical fingerprints in a few minutes instead of several hours to days, as is the case with genotyping methods. Although the method is generally applicable, we used 118 Staphylococcus aureus isolates to illustrate that the discriminatory power matches that of established genotyping techniques (numerical index of diversity [D]=0.989) and that concordance with the gold standard (pulsed-field gel electrophoresis) is high (95%). The Raman clustering of isolates was reproducible to the strain level for five independent cultures, despite the various culture times from 18 h to 24 h. Furthermore, this technique was able to classify stored (-80 degrees C) and recent isolates of a methicillin-resistant Staphylococcus aureus-colonized individual during surveillance studies and did so days earlier than established genotyping techniques did. Its high throughput and ease of use make it suitable for use in routine diagnostic laboratory settings. This will set the stage for continuous, automated, real-time epidemiological monitoring of bacterial infections in a hospital, which can then be followed by timely corrective action by infection prevention teams.

  1. Environmental epidemiology

    SciTech Connect

    Kopfler, F.C.; Craun, G.F.

    1986-01-01

    This volume is a compendium of peer-reviewed papers presented at the Symposium on Exposure Measurement and Evaluation Methods for Epidemiology, cosponsored in 1985 by the Health Effects Research Laboratory, USEPA, and the Division of Environmental Chemistry of the American Chemical Society. The book is divided into four sections: Use of Biological Monitoring to Assess Exposure, Epidemiologic Considerations for Assessing Exposure, Health and Exposure Data Bases, and Assessment of Exposure to Environmental Contaminants for Epidemiologic Studies. Both background papers and detailed reports of human studies are presented. The Biological Monitoring section contains reports of efforts to quantify adducts in blood and urine samples. In the section on Epidemiologic Considerations the feasibility of conducting epidemiologic studies of persons residing near hazardous waste sites and those exposed to arsenic in drinking water is described. The review of Data Bases includes government and industry water quality monitoring systems, the FDA Market Basket Study, major EPA air monitoring data, the National Database on Body Burden of Toxic chemicals, and the National Human Adipose Tissue Survey. Methods of assessing current exposure and estimating past exposure are detailed in the final section. Exposure to trichloroethylene in shower water, the relationship between water quality and cardiovascular disease, the contribution of environmental lead exposures to pediatric blood lead levels, and data from the TEAM study in which researchers compare indoor, outdoor, and breath analysis of air pollutant exposures are also discussed.

  2. An updated systematic review of epidemiological evidence on hormonal contraceptive methods and HIV acquisition in women

    PubMed Central

    Polis, Chelsea B.; Curtis, Kathryn M.; Hannaford, Philip C.; Phillips, Sharon J.; Chipato, Tsungai; Kiarie, James N.; Westreich, Daniel J.; Steyn, Petrus S.

    2016-01-01

    Objective and design: Some studies suggest that specific hormonal contraceptive methods [particularly depot medroxyprogesterone acetate (DMPA)] may increase women's HIV acquisition risk. We updated a systematic review to incorporate recent epidemiological data. Methods: We searched for articles published between 15 January 2014 and 15 January 2016 and hand-searched reference lists. We identified longitudinal studies comparing users of a specific hormonal contraceptive method against either nonusers of hormonal contraception or users of another specific hormonal contraceptive method. We added newly identified studies to those in the previous review, assessed study quality, created forest plots to display results, and conducted a meta-analysis for data on DMPA versus non-use of hormonal contraception. Results: We identified 10 new reports of which five were considered ‘unlikely to inform the primary question’. We focus on the other five reports, along with nine from the previous review, which were considered ‘informative but with important limitations’. The preponderance of data for oral contraceptive pills, injectable norethisterone enanthate, and levonorgestrel implants do not suggest an association with HIV acquisition, though data for implants are limited. The new, higher quality studies on DMPA (or nondisaggregated injectables), which had mixed results in terms of statistical significance, had hazard ratios between 1.2 and 1.7, consistent with our meta-analytic estimate for all higher quality studies of hazard ratio 1.4. Conclusion: Although confounding in these observational data cannot be excluded, new information increases concerns about DMPA and HIV acquisition risk in women. If the association is causal, the magnitude of effect is likely hazard ratio 1.5 or less. Data for other hormonal contraceptive methods, including norethisterone enanthate, are largely reassuring. PMID:27500670

  3. RADRUE METHOD FOR RECONSTRUCTION OF EXTERNAL PHOTON DOSES TO CHERNOBYL LIQUIDATORS IN EPIDEMIOLOGICAL STUDIES

    PubMed Central

    Kryuchkov, Victor; Chumak, Vadim; Maceika, Evaldas; Anspaugh, Lynn R.; Cardis, Elisabeth; Bakhanova, Elena; Golovanov, Ivan; Drozdovitch, Vladimir; Luckyanov, Nickolas; Kesminiene, Ausrele; Voillequé, Paul; Bouville, André

    2010-01-01

    Between 1986 and 1990, several hundred thousand workers, called “liquidators” or “clean-up workers”, took part in decontamination and recovery activities within the 30-km zone around the Chernobyl nuclear power plant in Ukraine, where a major accident occurred in April 1986. The Chernobyl liquidators were mainly exposed to external ionizing radiation levels that depended primarily on their work locations and the time after the accident when the work was performed. Because individual doses were often monitored inadequately or were not monitored at all for the majority of liquidators, a new method of photon (i.e. gamma and x-rays) dose assessment, called “RADRUE” (Realistic Analytical Dose Reconstruction with Uncertainty Estimation) was developed to obtain unbiased and reasonably accurate estimates for use in three epidemiologic studies of hematological malignancies and thyroid cancer among liquidators. The RADRUE program implements a time-and-motion dose reconstruction method that is flexible and conceptually easy to understand. It includes a large exposure rate database and interpolation and extrapolation techniques to calculate exposure rates at places where liquidators lived and worked within ~70 km of the destroyed reactor. The RADRUE technique relies on data collected from subjects’ interviews conducted by trained interviewers, and on expert dosimetrists to interpret the information and provide supplementary information, when necessary, based upon their own Chernobyl experience. The RADRUE technique was used to estimate doses from external irradiation, as well as uncertainties, to the bone-marrow for 929 subjects and to the thyroid gland for 530 subjects enrolled in epidemiologic studies. Individual bone-marrow dose estimates were found to range from less than one μGy to 3,300 mGy, with an arithmetic mean of 71 mGy. Individual thyroid dose estimates were lower and ranged from 20 μGy to 507 mGy, with an arithmetic mean of 29 mGy. The

  4. Genetic diversity of Bacillus anthracis in Europe: genotyping methods in forensic and epidemiologic investigations.

    PubMed

    Derzelle, Sylviane; Thierry, Simon

    2013-09-01

    Bacillus anthracis, the etiological agent of anthrax, a zoonosis relatively common throughout the world, can be used as an agent of bioterrorism. In naturally occurring outbreaks and in criminal release of this pathogen, a fast and accurate diagnosis is crucial to an effective response. Microbiological forensics and epidemiologic investigations increasingly rely on molecular markers, such as polymorphisms in DNA sequence, to obtain reliable information regarding the identification or source of a suspicious strain. Over the past decade, significant research efforts have been undertaken to develop genotyping methods with increased power to differentiate B. anthracis strains. A growing number of DNA signatures have been identified and used to survey B. anthracis diversity in nature, leading to rapid advances in our understanding of the global population of this pathogen. This article provides an overview of the different phylogenetic subgroups distributed across the world, with a particular focus on Europe. Updated information on the anthrax situation in Europe is reported. A brief description of some of the work in progress in the work package 5.1 of the AniBioThreat project is also presented, including (1) the development of a robust typing tool based on a suspension array technology and multiplexed single nucleotide polymorphisms scoring and (2) the typing of a collection of DNA from European isolates exchanged between the partners of the project. The know-how acquired will contribute to improving the EU's ability to react rapidly when the identity and real origin of a strain need to be established.

  5. Discriminatory Indices of Typing Methods for Epidemiologic Analysis of Contemporary Staphylococcus aureus Strains.

    PubMed

    Rodriguez, Marcela; Hogan, Patrick G; Satola, Sarah W; Crispell, Emily; Wylie, Todd; Gao, Hongyu; Sodergren, Erica; Weinstock, George M; Burnham, Carey-Ann D; Fritz, Stephanie A

    2015-09-01

    Historically, a number of typing methods have been evaluated for Staphylococcus aureus strain characterization. The emergence of contemporary strains of community-associated S. aureus, and the ensuing epidemic with a predominant strain type (USA300), necessitates re-evaluation of the discriminatory power of these typing methods for discerning molecular epidemiology and transmission dynamics, essential to investigations of hospital and community outbreaks. We compared the discriminatory index of 5 typing methods for contemporary S. aureus strain characterization. Children presenting to St. Louis Children's Hospital and community pediatric practices in St. Louis, Missouri (MO), with community-associated S. aureus infections were enrolled. Repetitive sequence-based PCR (repPCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal protein A (spa), and staphylococcal cassette chromosome (SCC) mec typing were performed on 200 S. aureus isolates. The discriminatory index of each method was calculated using the standard formula for this metric, where a value of 1 is highly discriminatory and a value of 0 is not discriminatory. Overall, we identified 26 distinct strain types by repPCR, 17 strain types by PFGE, 30 strain types by MLST, 68 strain types by spa typing, and 5 strain types by SCCmec typing. RepPCR had the highest discriminatory index (D) of all methods (D = 0.88), followed by spa typing (D = 0.87), MLST (D = 0.84), PFGE (D = 0.76), and SCCmec typing (D = 0.60). The method with the highest D among MRSA isolates was repPCR (D = 0.64) followed by spa typing (D = 0.45) and MLST (D = 0.44). The method with the highest D among MSSA isolates was spa typing (D = 0.98), followed by MLST (D = 0.93), repPCR (D = 0.92), and PFGE (D = 0.89). Among isolates designated USA300 by PFGE, repPCR was most discriminatory, with 10 distinct strain types identified (D = 0.63). We identified 45

  6. Discriminatory Indices of Typing Methods for Epidemiologic Analysis of Contemporary Staphylococcus aureus Strains

    PubMed Central

    Rodriguez, Marcela; Hogan, Patrick G.; Satola, Sarah W.; Crispell, Emily; Wylie, Todd; Gao, Hongyu; Sodergren, Erica; Weinstock, George M.; Burnham, Carey-Ann D.; Fritz, Stephanie A.

    2015-01-01

    Abstract Historically, a number of typing methods have been evaluated for Staphylococcus aureus strain characterization. The emergence of contemporary strains of community-associated S. aureus, and the ensuing epidemic with a predominant strain type (USA300), necessitates re-evaluation of the discriminatory power of these typing methods for discerning molecular epidemiology and transmission dynamics, essential to investigations of hospital and community outbreaks. We compared the discriminatory index of 5 typing methods for contemporary S. aureus strain characterization. Children presenting to St. Louis Children's Hospital and community pediatric practices in St. Louis, Missouri (MO), with community-associated S. aureus infections were enrolled. Repetitive sequence-based PCR (repPCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal protein A (spa), and staphylococcal cassette chromosome (SCC) mec typing were performed on 200 S. aureus isolates. The discriminatory index of each method was calculated using the standard formula for this metric, where a value of 1 is highly discriminatory and a value of 0 is not discriminatory. Overall, we identified 26 distinct strain types by repPCR, 17 strain types by PFGE, 30 strain types by MLST, 68 strain types by spa typing, and 5 strain types by SCCmec typing. RepPCR had the highest discriminatory index (D) of all methods (D = 0.88), followed by spa typing (D = 0.87), MLST (D = 0.84), PFGE (D = 0.76), and SCCmec typing (D = 0.60). The method with the highest D among MRSA isolates was repPCR (D = 0.64) followed by spa typing (D = 0.45) and MLST (D = 0.44). The method with the highest D among MSSA isolates was spa typing (D = 0.98), followed by MLST (D = 0.93), repPCR (D = 0.92), and PFGE (D = 0.89). Among isolates designated USA300 by PFGE, repPCR was most discriminatory, with 10 distinct strain types identified (D = 0.63). We

  7. Phene Plate (PhP) biochemical fingerprinting. A screening method for epidemiological typing of enterococcal isolates.

    PubMed

    Saeedi, B; Tärnberg, M; Gill, H; Hällgren, A; Jonasson, J; Nilsson, L E; Isaksson, B; Kühn, I; Hanberger, H

    2005-09-01

    Pulsed-field gel electrophoresis (PFGE) is currently considered the gold standard for genotyping of enterococci. However, PFGE is both expensive and time-consuming. The purpose of this study was to investigate whether the PhP system can be used as a reliable clinical screening method for detection of genetically related isolates of enterococci. If so, it should be possible to minimize the number of isolates subjected to PFGE typing, which would save time and money. Ninety-nine clinical enterococcal isolates were analysed by PhP (similarity levels 0.90-0.975) and PFGE (similarity levels < or =3 and < or =6 bands) and all possible pairs of isolates were cross-classified as matched or mismatched. We found that the probability that a pair of isolates (A and B) belonging to the same type according to PhP also belong to the same cluster according to PFGE, i.e. p(A(PFGE)=B(PFGE) * A(PhP)=B(PhP)), and the probability that a pair of isolates of different types according to PhP also belong to different clusters according to PFGE, i.e. p(A(PFGE) not equalB(PFGE) * A(PhP) not equalB(PhP)), was relatively high for E. faecalis (0.86 and 0.96, respectively), but was lower for E. faecium (0.51 and 0.77, respectively). The concordance which shows the probability that PhP and PFGE agree on match or mismatch was 86%-93% for E. faecalis and 54%-66% for E. faecium, which indicates that the PhP method may be useful for epidemiological typing of E. faecalis in the current settings but not for E. faecium.

  8. [Dermato-epidemiology].

    PubMed

    Apfelbacher, C J; Diepgen, T L; Weisshaar, E

    2011-11-01

    Dermato-epidemiology is an important scientific discipline which investigates skin diseases using epidemiological methods. Epidemiology is the science of the distribution and determinants of disease in specified populations. We describe fundamental terms of dermato-epidemiology (measures of disease occurrence, measures of risk), different study types (observational studies, interventional studies), the selection of statistical tests, bias and confounding as well as the principles of evidence-based dermatology, and give illustrative examples.

  9. Age-Based Methods to Explore Time-Related Variables in Occupational Epidemiology Studies

    SciTech Connect

    Janice P. Watkins, Edward L. Frome, Donna L. Cragle

    2005-08-31

    Although age is recognized as the strongest predictor of mortality in chronic disease epidemiology, a calendar-based approach is often employed when evaluating time-related variables. An age-based analysis file, created by determining the value of each time-dependent variable for each age that a cohort member is followed, provides a clear definition of age at exposure and allows development of diverse analytic models. To demonstrate methods, the relationship between cancer mortality and external radiation was analyzed with Poisson regression for 14,095 Oak Ridge National Laboratory workers. Based on previous analysis of this cohort, a model with ten-year lagged cumulative radiation doses partitioned by receipt before (dose-young) or after (dose-old) age 45 was examined. Dose-response estimates were similar to calendar-year-based results with elevated risk for dose-old, but not when film badge readings were weekly before 1957. Complementary results showed increasing risk with older hire ages and earlier birth cohorts, since workers hired after age 45 were born before 1915, and dose-young and dose-old were distributed differently by birth cohorts. Risks were generally higher for smokingrelated than non-smoking-related cancers. It was difficult to single out specific variables associated with elevated cancer mortality because of: (1) birth cohort differences in hire age and mortality experience completeness, and (2) time-period differences in working conditions, dose potential, and exposure assessment. This research demonstrated the utility and versatility of the age-based approach.

  10. Epidemiological causality.

    PubMed

    Morabia, Alfredo

    2005-01-01

    Epidemiological methods, which combine population thinking and group comparisons, can primarily identify causes of disease in populations. There is therefore a tension between our intuitive notion of a cause, which we want to be deterministic and invariant at the individual level, and the epidemiological notion of causes, which are invariant only at the population level. Epidemiologists have given heretofore a pragmatic solution to this tension. Causal inference in epidemiology consists in checking the logical coherence of a causality statement and determining whether what has been found grossly contradicts what we think we already know: how strong is the association? Is there a dose-response relationship? Does the cause precede the effect? Is the effect biologically plausible? Etc. This approach to causal inference can be traced back to the English philosophers David Hume and John Stuart Mill. On the other hand, the mode of establishing causality, devised by Jakob Henle and Robert Koch, which has been fruitful in bacteriology, requires that in every instance the effect invariably follows the cause (e.g., inoculation of Koch bacillus and tuberculosis). This is incompatible with epidemiological causality which has to deal with probabilistic effects (e.g., smoking and lung cancer), and is therefore invariant only for the population.

  11. Comparison of epidemiological marker methods for identification of Salmonella typhimurium isolates from an outbreak caused by contaminated chocolate.

    PubMed Central

    Kapperud, G; Lassen, J; Dommarsnes, K; Kristiansen, B E; Caugant, D A; Ask, E; Jahkola, M

    1989-01-01

    Plasmid profile analysis, restriction endonuclease analysis, and multilocus enzyme electrophoresis were used in conjunction with serotyping, bacteriophage typing, and biochemical fingerprinting to trace epidemiologically related isolates of Salmonella typhimurium from an outbreak caused by contaminated chocolate products in Norway and Finland. To evaluate the efficiency of the epidemiological marker methods, isolates from the outbreak were compared with five groups of control isolates not known to be associated with the outbreak. Both plasmid profile analysis and phage typing provided further discrimination over that produced by serotyping and biochemical fingerprinting. Plasmid profile analysis and phage typing were equally reliable in differentiating the outbreak isolates from the epidemiologically unrelated controls and were significantly more effective than multilocus enzyme electrophoresis and restriction enzyme analysis of total DNA. The greatest differentiation was achieved when plasmid profile analysis and phage typing were combined to complement serotyping and biochemical fingerprinting. However, none of the methods employed, including restriction enzyme analysis of plasmid DNA, were able to distinguish the outbreak isolates from five isolates recovered in Norway and Finland over a period of years from dead passerine birds and a calf. Images PMID:2674198

  12. Epidemiologic study of residential proximity to transmission lines and childhood cancer in California: description of design, epidemiologic methods and study population.

    PubMed

    Kheifets, Leeka; Crespi, Catherine M; Hooper, Chris; Oksuzyan, Sona; Cockburn, Myles; Ly, Thomas; Mezei, Gabor

    2015-01-01

    We conducted a large epidemiologic case-control study in California to examine the association between childhood cancer risk and distance from the home address at birth to the nearest high-voltage overhead transmission line as a replication of the study of Draper et al. in the United Kingdom. We present a detailed description of the study design, methods of case ascertainment, control selection, exposure assessment and data analysis plan. A total of 5788 childhood leukemia cases and 3308 childhood central nervous system cancer cases (included for comparison) and matched controls were available for analysis. Birth and diagnosis addresses of cases and birth addresses of controls were geocoded. Distance from the home to nearby overhead transmission lines was ascertained on the basis of the electric power companies' geographic information system (GIS) databases, additional Google Earth aerial evaluation and site visits to selected residences. We evaluated distances to power lines up to 2000 m and included consideration of lower voltages (60-69 kV). Distance measures based on GIS and Google Earth evaluation showed close agreement (Pearson correlation >0.99). Our three-tiered approach to exposure assessment allowed us to achieve high specificity, which is crucial for studies of rare diseases with low exposure prevalence.

  13. [Phenotypic and genotypic methods for epidemiological typing of veterinary important bacterial pathogens of the genera Staphylococcus, Salmonella, and Pasteurella].

    PubMed

    Schwarz, Stefan; Blickwede, Maren; Kehrenberg, Corinna; Michael, Geovana Brenner

    2003-01-01

    Molecular typing methods are capable of providing detailed strain characteristics which are commonly far beyond the capacities of phenotypic typing methods. Such molecular-based characteristics have proved to be very helpful in epidemiological studies of bacterial pathogens. The primary criteria that all typing methods should fulfill include (1) the typeability of the strains in question, (2) the reproducibility of the results, and (3) a high discriminatory power. In general, molecular typing methods can be differentiated with regard to their use in methods that can be applied to virtually all bacteria (e.g. plasmid profiling, ribotyping, macrorestriction analysis) and methods which can only be used for typing of certain bacterial genera or species (e.g. IS200 typing of certain Salmonella enterica subsp. enterica serovars, or coa-PCR of coagulase-positive staphylococci). In the present review, various phenotypic and molecular methods for the epidemiological typing of bacteria of the genera Staphylococcus, Salmonella, and Pasteurella are described and their advantages/disadvantages--also with regard to the fulfillment of the above-mentioned primary criteria--are critically assessed.

  14. Overview of the epidemiology methods and applications: strengths and limitations of observational study designs.

    PubMed

    Colditz, Graham A

    2010-01-01

    The impact of study design on the results of medical research has long been an area of both substantial debate and a smaller body of empirical research. Examples come from many disciplines within clinical and public health research. Among the early major contributions in the 1970s was work by Mosteller and colleagues (Gilbert et al., 1997), who noted that innovations in surgery and anesthesia showed greater gains than standard therapy when nonrandomized, controlled trials were evaluated compared with the gains reported in randomized, controlled trials. More recently, we and others have evaluated the impact of design in medical and surgical research, and concluded that the mean gain comparing new therapies to established therapies was biased by study design in nonrandomized trials (Colditz et al., 1989; Miller et al., 1989). Benson and Hartz (2000) conducted a study in which they focused only on studies reported after 1985. On the basis of 136 reports of 19 diverse treatments, Benson and Hartz concluded that in only 2 of the 19 analyses did the combined data from the observational studies lie outside the 95% confidence interval for the combined data from the randomized trials. A similar study drew only on data reported from 1991 to 1995, which showed remarkably similar results among observational studies and randomized, controlled trials (Concato et al., 2000). These more recent data suggest that advancing the study design and analytic methods may reduce bias in some evaluations of medical and public health interventions. Such methods apply not only to the original studies, but also to the approaches that are taken to quantitatively combine results by using meta-analytic approaches such as random effects meta-regression, Bayesian meta-analysis, and the like (Normand, 1999). By focusing attention on thorough data analysis, design issues can be understood and their impact or bias can be estimated, on average, and then ideally accounted for in the interpretation of

  15. Review of methods of dose estimation for epidemiological studies of the radiological impact of nevada test site and global fallout.

    PubMed

    Beck, Harold L; Anspaugh, Lynn R; Bouville, André; Simon, Steven L

    2006-07-01

    Methods to assess radiation doses from nuclear weapons test fallout have been used to estimate doses to populations and individuals in a number of studies. However, only a few epidemiology studies have relied on fallout dose estimates. Though the methods for assessing doses from local and regional compared to global fallout are similar, there are significant differences in predicted doses and contributing radionuclides depending on the source of the fallout, e.g. whether the nuclear debris originated in Nevada at the U.S. nuclear test site or whether it originated at other locations worldwide. The sparse historical measurement data available are generally sufficient to estimate external exposure doses reasonably well. However, reconstruction of doses to body organs from ingestion and inhalation of radionuclides is significantly more complex and is almost always more uncertain than are external dose estimates. Internal dose estimates are generally based on estimates of the ground deposition per unit area of specific radionuclides and subsequent transport of radionuclides through the food chain. A number of technical challenges to correctly modeling deposition of fallout under wet and dry atmospheric conditions still remain, particularly at close-in locations where sizes of deposited particles vary significantly over modest changes in distance. This paper summarizes the various methods of dose estimation from weapons test fallout and the most important dose assessment and epidemiology studies that have relied on those methods.

  16. A Review of Exposure Assessment Methods in Epidemiological Studies on Incinerators

    PubMed Central

    Ranzi, Andrea; De Leo, Giulio A.; Lauriola, Paolo

    2013-01-01

    Incineration is a common technology for waste disposal, and there is public concern for the health impact deriving from incinerators. Poor exposure assessment has been claimed as one of the main causes of inconsistency in the epidemiological literature. We reviewed 41 studies on incinerators published between 1984 and January 2013 and classified them on the basis of exposure assessment approach. Moreover, we performed a simulation study to explore how the different exposure metrics may influence the exposure levels used in epidemiological studies. 19 studies used linear distance as a measure of exposure to incinerators, 11 studies atmospheric dispersion models, and the remaining 11 studies a qualitative variable such as presence/absence of the source. All reviewed studies utilized residence as a proxy for population exposure, although residence location was evaluated with different precision (e.g., municipality, census block, or exact address). Only one study reconstructed temporal variability in exposure. Our simulation study showed a notable degree of exposure misclassification caused by the use of distance compared to dispersion modelling. We suggest that future studies (i) make full use of pollution dispersion models; (ii) localize population on a fine-scale; and (iii) explicitly account for the presence of potential environmental and socioeconomic confounding. PMID:23840228

  17. An IARC Manual series aimed at assisting cancer epidemiology and prevention. "Environmental carcinogens: selected methods of analysis".

    PubMed

    O'Neill, I K; Fishbein, L

    1986-01-01

    Since 1975, the IARC has been preparing a series of volumes entitled "Environmental Carcinogens: Selected Methods of Analysis" (IARC Manual series) of which the purposes are to assist analysts, epidemiologists and regulatory authorities in planning or performing exposure measurements that are truly comparable between different studies. The Manual series provides expert information within each volume on multi-media sampling, methods of analyses and some background of epidemiology, metabolism, use/occurrence for a group of known or suspect carcinogens. So far, eleven volumes have been published or are in preparation on the following subjects: N-nitrosamines, vinyl chloride, PAH, aromatic amines, mycotoxins, N-nitroso compounds, volatile halogenated hydrocarbons, metals, passive smoking, benzene and alkylated benzenes, dioxins, PCDFs and PCBs. The presentation will discuss needs and priorities for use of analytical chemistry in estimating exposures of apparently greatest relevance to cancer causation, i.e. the approach to developing this series. Indications from epidemiology, evaluations of carcinogenic risk to humans, and recent developments in total exposure assessment are that new methods and matrices need more emphasis, e.g. as with biochemical dosimetry, exhaled breath, and in indoor air.

  18. Design and implementation of epidemiological field investigation method based on mobile collaboration

    NASA Astrophysics Data System (ADS)

    Zhang, Lihui; Wang, Dongchuan; Huang, Mingxiang; Gong, Jianhua; Fang, Liqun; Cao, Wuchun

    2008-10-01

    With the development of mobile technologies and the integration with the spatial information technologies, it becomes possible to provide a potential to develop new techno-support solutions to Epidemiological Field Investigation especially for the disposal of emergent public health events. Based on mobile technologies and virtual geographic environment, the authors have designed a model for collaborative work in four communication patterns, namely, S2S (Static to Static), M2S (Mobile to Static), S2M (Static to Mobile), and M2M (Mobile to Mobile). Based on the model mentioned above, this paper stresses to explore mobile online mapping regarding mobile collaboration and conducts an experimental case study of HFRS (Hemorrhagic Fever with Renal Syndrome) fieldwork, and then develops a prototype system of emergent response disposition information system to test the effectiveness and usefulness of field survey based on mobile collaboration.

  19. Surveillance in a Telemedicine Setting: Application of Epidemiologic Methods at NASA Johnson Space Center Adriana

    NASA Technical Reports Server (NTRS)

    Babiak-Vazquez, Adriana; Ruffaner, Lanie; Wear, Mary; Crucian Brian; Sams, Clarence; Lee, Lesley R.; Van Baalen, Mary

    2016-01-01

    Space medicine presents unique challenges and opportunities for epidemiologists, such as the use of telemedicine during spaceflight. Medical capabilities aboard the International Space Station (ISS) are limited due to severe restrictions on power, volume, and mass. Consequently, inflight health information is based heavily on crewmember (CM) self-report of signs and symptoms, rather than formal diagnoses. While CM's are in flight, the primary source of crew health information is verbal communication between physicians and crewmembers. In 2010 NASA implemented the Lifetime Surveillance of Astronaut Health, an occupational surveillance program for the U.S. Astronaut corps. This has shifted the epidemiological paradigm from tracking diagnoses based on traditional terrestrial clinical practice to one that incorporates symptomatology and may gain a more population-based understanding of early detection of disease process.

  20. Meta-epidemiology.

    PubMed

    Bae, Jong-Myon

    2014-01-01

    The concept of meta-epidemiology has been introduced with considering the methodological limitations of systematic review for intervention trials. The paradigm of meta-epidemiology has shifted from a statistical method into a new methodology to close gaps between evidence and practice. Main interest of meta-epidemiology is to control potential biases in previous quantitative systematic reviews and draw appropriate evidences for establishing evidence-base guidelines. Nowadays, the network meta-epidemiology was suggested in order to overcome some limitations of meta-epidemiology. To activate meta-epidemiologic studies, implementation of tools for risk of bias and reporting guidelines such as the Consolidated Standards for Reporting Trials (CONSORT) should be done.

  1. Measuring socio-economic position for epidemiological studies in low- and middle-income countries: a methods of measurement in epidemiology paper

    PubMed Central

    Howe, Laura D; Galobardes, Bruna; Matijasevich, Alicia; Gordon, David; Johnston, Deborah; Onwujekwe, Obinna; Patel, Rita; Webb, Elizabeth A; Lawlor, Debbie A; Hargreaves, James R

    2012-01-01

    Much has been written about the measurement of socio-economic position (SEP) in high-income countries (HIC). Less has been written for an epidemiology, health systems and public health audience about the measurement of SEP in low- and middle-income countries (LMIC). The social stratification processes in many LMIC—and therefore the appropriate measurement tools—differ considerably from those in HIC. Many measures of SEP have been utilized in epidemiological studies; the aspects of SEP captured by these measures and the pathways through which they may affect health are likely to be slightly different but overlapping. No single measure of SEP will be ideal for all studies and contexts; the strengths and limitations of a given indicator are likely to vary according to the specific research question. Understanding the general properties of different indicators, however, is essential for all those involved in the design or interpretation of epidemiological studies. In this article, we describe the measures of SEP used in LMIC. We concentrate on measures of individual or household-level SEP rather than area-based or ecological measures such as gross domestic product. We describe each indicator in terms of its theoretical basis, interpretation, measurement, strengths and limitations. We also provide brief comparisons between LMIC and HIC for each measure. PMID:22438428

  2. Epidemiologic Methods Lessons Learned from Environmental Public Health Disasters: Chernobyl, the World Trade Center, Bhopal, and Graniteville, South Carolina

    PubMed Central

    Svendsen, Erik R.; Runkle, Jennifer R.; Dhara, Venkata Ramana; Lin, Shao; Naboka, Marina; Mousseau, Timothy A.; Bennett, Charles

    2012-01-01

    Background: Environmental public health disasters involving hazardous contaminants may have devastating effects. While much is known about their immediate devastation, far less is known about long-term impacts of these disasters. Extensive latent and chronic long-term public health effects may occur. Careful evaluation of contaminant exposures and long-term health outcomes within the constraints imposed by limited financial resources is essential. Methods: Here, we review epidemiologic methods lessons learned from conducting long-term evaluations of four environmental public health disasters involving hazardous contaminants at Chernobyl, the World Trade Center, Bhopal, and Graniteville (South Carolina, USA). Findings: We found several lessons learned which have direct implications for the on-going disaster recovery work following the Fukushima radiation disaster or for future disasters. Interpretation: These lessons should prove useful in understanding and mitigating latent health effects that may result from the nuclear reactor accident in Japan or future environmental public health disasters. PMID:23066404

  3. Realist explanatory theory building method for social epidemiology: a protocol for a mixed method multilevel study of neighbourhood context and postnatal depression.

    PubMed

    Eastwood, John G; Jalaludin, Bin B; Kemp, Lynn A

    2014-01-01

    A recent criticism of social epidemiological studies, and multi-level studies in particular has been a paucity of theory. We will present here the protocol for a study that aims to build a theory of the social epidemiology of maternal depression. We use a critical realist approach which is trans-disciplinary, encompassing both quantitative and qualitative traditions, and that assumes both ontological and hierarchical stratification of reality. We describe a critical realist Explanatory Theory Building Method comprising of an: 1) emergent phase, 2) construction phase, and 3) confirmatory phase. A concurrent triangulated mixed method multilevel cross-sectional study design is described. The Emergent Phase uses: interviews, focus groups, exploratory data analysis, exploratory factor analysis, regression, and multilevel Bayesian spatial data analysis to detect and describe phenomena. Abductive and retroductive reasoning will be applied to: categorical principal component analysis, exploratory factor analysis, regression, coding of concepts and categories, constant comparative analysis, drawing of conceptual networks, and situational analysis to generate theoretical concepts. The Theory Construction Phase will include: 1) defining stratified levels; 2) analytic resolution; 3) abductive reasoning; 4) comparative analysis (triangulation); 5) retroduction; 6) postulate and proposition development; 7) comparison and assessment of theories; and 8) conceptual frameworks and model development. The strength of the critical realist methodology described is the extent to which this paradigm is able to support the epistemological, ontological, axiological, methodological and rhetorical positions of both quantitative and qualitative research in the field of social epidemiology. The extensive multilevel Bayesian studies, intensive qualitative studies, latent variable theory, abductive triangulation, and Inference to Best Explanation provide a strong foundation for Theory

  4. Variable genetic element typing: a quick method for epidemiological subtyping of Legionella pneumophila.

    PubMed

    Pannier, K; Heuner, K; Lück, C

    2010-04-01

    A total of 57 isolates of Legionella pneumophila were randomly selected from the German National Legionella strain collection and typed by monoclonal antibody subgrouping, seven-gene locus sequence-based typing (SBT) scheme and a newly developed variable element typing (VET) system based on the presence or absence of ten variable genetic elements. These elements were detected while screening a genomic library of strain Corby, as well as being taken from published data for PAI-1 (pathogenicity island) from strain Philadelphia. Specific primers were designed and used in gel-based polymerase chain reaction (PCR) assays. PCR amplification of the mip gene served as a control. The end-point was the presence/absence of a PCR product on an ethidium bromide-strained gel. In the present study, the index of discrimination was somewhat lower than that of the SBT (0.87 versus 0.97). Nevertheless, the results obtained showed as a 'proof of principle' that this simple and quick typing assay might be useful for the epidemiological characterisation of L. pneumophila strains.

  5. The causal pie model: an epidemiological method applied to evolutionary biology and ecology.

    PubMed

    Wensink, Maarten; Westendorp, Rudi G J; Baudisch, Annette

    2014-05-01

    A general concept for thinking about causality facilitates swift comprehension of results, and the vocabulary that belongs to the concept is instrumental in cross-disciplinary communication. The causal pie model has fulfilled this role in epidemiology and could be of similar value in evolutionary biology and ecology. In the causal pie model, outcomes result from sufficient causes. Each sufficient cause is made up of a "causal pie" of "component causes". Several different causal pies may exist for the same outcome. If and only if all component causes of a sufficient cause are present, that is, a causal pie is complete, does the outcome occur. The effect of a component cause hence depends on the presence of the other component causes that constitute some causal pie. Because all component causes are equally and fully causative for the outcome, the sum of causes for some outcome exceeds 100%. The causal pie model provides a way of thinking that maps into a number of recurrent themes in evolutionary biology and ecology: It charts when component causes have an effect and are subject to natural selection, and how component causes affect selection on other component causes; which partitions of outcomes with respect to causes are feasible and useful; and how to view the composition of a(n apparently homogeneous) population. The diversity of specific results that is directly understood from the causal pie model is a test for both the validity and the applicability of the model. The causal pie model provides a common language in which results across disciplines can be communicated and serves as a template along which future causal analyses can be made.

  6. Global Dissemination of Carbapenemase-Producing Klebsiella pneumoniae: Epidemiology, Genetic Context, Treatment Options, and Detection Methods

    PubMed Central

    Lee, Chang-Ro; Lee, Jung Hun; Park, Kwang Seung; Kim, Young Bae; Jeong, Byeong Chul; Lee, Sang Hee

    2016-01-01

    The emergence of carbapenem-resistant Gram-negative pathogens poses a serious threat to public health worldwide. In particular, the increasing prevalence of carbapenem-resistant Klebsiella pneumoniae is a major source of concern. K. pneumoniae carbapenemases (KPCs) and carbapenemases of the oxacillinase-48 (OXA-48) type have been reported worldwide. New Delhi metallo-β-lactamase (NDM) carbapenemases were originally identified in Sweden in 2008 and have spread worldwide rapidly. In this review, we summarize the epidemiology of K. pneumoniae producing three carbapenemases (KPCs, NDMs, and OXA-48-like). Although the prevalence of each resistant strain varies geographically, K. pneumoniae producing KPCs, NDMs, and OXA-48-like carbapenemases have become rapidly disseminated. In addition, we used recently published molecular and genetic studies to analyze the mechanisms by which these three carbapenemases, and major K. pneumoniae clones, such as ST258 and ST11, have become globally prevalent. Because carbapenemase-producing K. pneumoniae are often resistant to most β-lactam antibiotics and many other non-β-lactam molecules, the therapeutic options available to treat infection with these strains are limited to colistin, polymyxin B, fosfomycin, tigecycline, and selected aminoglycosides. Although, combination therapy has been recommended for the treatment of severe carbapenemase-producing K. pneumoniae infections, the clinical evidence for this strategy is currently limited, and more accurate randomized controlled trials will be required to establish the most effective treatment regimen. Moreover, because rapid and accurate identification of the carbapenemase type found in K. pneumoniae may be difficult to achieve through phenotypic antibiotic susceptibility tests, novel molecular detection techniques are currently being developed. PMID:27379038

  7. Optimization and Application of Direct Infusion Nanoelectrospray HRMS Method for Large-Scale Urinary Metabolic Phenotyping in Molecular Epidemiology

    PubMed Central

    2017-01-01

    Large-scale metabolic profiling requires the development of novel economical high-throughput analytical methods to facilitate characterization of systemic metabolic variation in population phenotypes. We report a fit-for-purpose direct infusion nanoelectrospray high-resolution mass spectrometry (DI-nESI-HRMS) method with time-of-flight detection for rapid targeted parallel analysis of over 40 urinary metabolites. The newly developed 2 min infusion method requires <10 μL of urine sample and generates high-resolution MS profiles in both positive and negative polarities, enabling further data mining and relative quantification of hundreds of metabolites. Here we present optimization of the DI-nESI-HRMS method in a detailed step-by-step guide and provide a workflow with rigorous quality assessment for large-scale studies. We demonstrate for the first time the application of the method for urinary metabolic profiling in human epidemiological investigations. Implementation of the presented DI-nESI-HRMS method enabled cost-efficient analysis of >10 000 24 h urine samples from the INTERMAP study in 12 weeks and >2200 spot urine samples from the ARIC study in <3 weeks with the required sensitivity and accuracy. We illustrate the application of the technique by characterizing the differences in metabolic phenotypes of the USA and Japanese population from the INTERMAP study. PMID:28245357

  8. The Epidemiology of Substance Use Disorders in US Veterans: A Systematic Review and Analysis of Assessment Methods

    PubMed Central

    Lan, Chiao-Wen; Fiellin, David A.; Barry, Declan T.; Bryant, Kendall J.; Gordon, Adam J.; Edelman, E. Jennifer; Gaither, Julie R.; Maisto, Stephen A.; Marshall, Brandon D.L.

    2016-01-01

    Background Substance use disorders (SUDs), which encompass alcohol and drug use disorders (AUDs, DUDs), constitute a major public health challenge among US veterans. SUDs are among the most common and costly of all health conditions among veterans. Objectives This study sought to examine the epidemiology of SUDs among US veterans, compare the prevalence of SUDs in studies using diagnostic and administrative criteria assessment methods, and summarize trends in the prevalence of SUDs reported in studies sampling US veterans over time. Methods Comprehensive electronic database searches were conducted. A total of 3,490 studies were identified. We analyzed studies sampling US veterans and reporting prevalence, distribution, and examining AUDs and DUDs. Results Of the studies identified, 72 met inclusion criteria. The studies were published between 1995 and 2013. Studies using diagnostic criteria reported higher prevalence of AUDs (32% vs. 10%) and DUDs (20% vs. 5%) than administrative criteria, respectively. Regardless of assessment method, both the lifetime and past year prevalence of AUDs in studies sampling US veterans has declined gradually over time. Conclusion The prevalence of SUDs reported in studies sampling US veterans are affected by assessment method. Given the significant public health problems of SUDs among US veterans, improved guidelines for clinical screening using validated diagnostic criteria to assess AUDs and DUDs in US veteran populations are needed. Scientific Significance These findings may inform VA and other healthcare systems in prevention, diagnosis, and intervention for SUDs among US veterans. PMID:26693830

  9. MEASUREMENT ERROR ESTIMATION AND CORRECTION METHODS TO MINIMIZE EXPOSURE MISCLASSIFICATION IN EPIDEMIOLOGICAL STUDIES: PROJECT SUMMARY

    EPA Science Inventory

    This project summary highlights recent findings from research undertaken to develop improved methods to assess potential human health risks related to drinking water disinfection byproduct (DBP) exposures.

  10. INFLUENCE OF EXPOSURE ASSESSMENT METHOD IN AN EPIDEMIOLOGIC STUDY OF TRIHALOMETHANE EXPOSURE AND SPONTANEOUS ABORTION

    EPA Science Inventory

    Trihalomethanes are common contaminants of chlorinated drinking water. Studies of their health effects have been hampered by exposure misclassification, due in part to limitations inherent in using utility sampling records. We used two exposure assessment methods, one based on ut...

  11. Method to Select Metropolitan Areas of Epidemiologic Interest for Enhanced Air Quality Monitoring

    EPA Science Inventory

    The U.S. Environmental Protection Agency’s current Speciation Trends Network (STN) covers most major U.S. metropolitan areas and a wide range of particulate matter (PM) constituents and gaseous co-pollutants. However, using filter-based methods, most PM constituents are measured ...

  12. Novel Microbiological and Spatial Statistical Methods to Improve Strength of Epidemiological Evidence in a Community-Wide Waterborne Outbreak

    PubMed Central

    Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W.; Hänninen, Marja-Liisa; Pitkänen, Tarja

    2014-01-01

    Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9–16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak. PMID:25147923

  13. Novel microbiological and spatial statistical methods to improve strength of epidemiological evidence in a community-wide waterborne outbreak.

    PubMed

    Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W; Hänninen, Marja-Liisa; Pitkänen, Tarja

    2014-01-01

    Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9-16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak.

  14. Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology-Veterinary (STROBE-Vet) Statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-12-01

    Reporting of observational studies in veterinary research presents challenges that often are not addressed in published reporting guidelines. Our objective was to develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. We conducted a consensus meeting with 17 experts in Mississauga, Canada. Experts completed a premeeting survey about whether items in the STROBE statement should be modified or added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. During the meeting, each STROBE item was discussed to determine whether or not rewording was recommended, and whether additions were warranted. Anonymous voting was used to determine consensus. Six items required no modifications or additions. Modifications or additions were made to the STROBE items 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources and measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations), and 22 (funding). The methods and processes used were similar to those used for other extensions of the STROBE statement. The use of this STROBE statement extension should improve reporting of observational studies in veterinary research by recognizing unique features of observational studies involving food-producing and companion animals, products of animal origin, aquaculture, and wildlife.

  15. [Epidemiology and heterogeny].

    PubMed

    Breilh, J; Granda, E

    1989-01-01

    The innovation of epidemiology plays a crucial role in the development of the health sciences. The authors emphasize the importance of epistemological analysis related to scientific and technical production. They focus on the theoretical and methodological contributions of the principal Latin American groups in the field of epidemiology, stating their main accomplishments, issues and potentials. When reviewing those conceptual and practical innovations, the authors analyse the effects of broader historical conditions on scientific work. To them, Latin American contemporary innovative epidemiological research and production have developed clearly differentiated principles, methods and technical projections which have led to a movement of critical or 'social' epidemiology. The functionalist approach of conventional epidemiology, characterized by an empiricist viewpoint, is being overcome by a more rigorous and analytical approach. This new epidemiological approach, in which the authors as members of CEAS (Health Research and Advisory Center) are working, has selectively incorporated some of the technical instruments of conventional epidemiology, subordinating them to a different theoretical and logical paradigm. The new framework of this group explains the need to consider the people's objective situation and necessities, when constructing scientific interpretations and planning technical action. In order to accomplish this goal, epidemiological reasoning has to reflect the unity of external epidemiological facts and associations, the so-called phenomenological aspect of health, with the underlying determinants and conditioning processes or internal relations, which are the essence of the health-disease production and distribution process. Epidemiological analysis is considered not only as a problem of empirical observation but as a process of theoretical construction, in which there is a dynamic fusion of deductive and inductive reasoning.(ABSTRACT TRUNCATED AT 250

  16. A graph-theory method for pattern identification in geographical epidemiology – a preliminary application to deprivation and mortality

    PubMed Central

    Maheswaran, Ravi; Craigs, Cheryl; Read, Simon; Bath, Peter A; Willett, Peter

    2009-01-01

    Background Graph theoretical methods are extensively used in the field of computational chemistry to search datasets of compounds to see if they contain particular molecular sub-structures or patterns. We describe a preliminary application of a graph theoretical method, developed in computational chemistry, to geographical epidemiology in relation to testing a prior hypothesis. We tested the methodology on the hypothesis that if a socioeconomically deprived neighbourhood is situated in a wider deprived area, then that neighbourhood would experience greater adverse effects on mortality compared with a similarly deprived neighbourhood which is situated in a wider area with generally less deprivation. Methods We used the Trent Region Health Authority area for this study, which contained 10,665 census enumeration districts (CED). Graphs are mathematical representations of objects and their relationships and within the context of this study, nodes represented CEDs and edges were determined by whether or not CEDs were neighbours (shared a common boundary). The overall area in this study was represented by one large graph comprising all CEDs in the region, along with their adjacency information. We used mortality data from 1988–1998, CED level population estimates and the Townsend Material Deprivation Index as an indicator of neighbourhood level deprivation. We defined deprived CEDs as those in the top 20% most deprived in the Region. We then set out to classify these deprived CEDs into seven groups defined by increasing deprivation levels in the neighbouring CEDs. 506 (24.2%) of the deprived CEDs had five adjacent CEDs and we limited pattern development and searching to these CEDs. We developed seven query patterns and used the RASCAL (Rapid Similarity Calculator) program to carry out the search for each of the query patterns. This program used a maximum common subgraph isomorphism method which was modified to handle geographical data. Results Of the 506 deprived CEDs

  17. [Pharmacological vigilance and pharmacological epidemiology: principles, definition, methods and current trends in neurology].

    PubMed

    Montastruc, J L; Bagheri, H; Lapeyre-Mestre, M; Senard, J M

    1999-04-01

    It is now well established that only clinical trials performed before drug approval are not sufficient for a full modern pharmacological evaluation of drugs and treatments. The need of both pharmacovigilance and pharmacoepidemiology is underlined in order to evaluate drugs under real conditions. After a summary of methods used in pharmacoepidemiological trials (spontaneous reports, imputability assessment, cohorts, case control studies etc.), recent pharmacoepidemiological data useful for the neurologist are summarized: side effects of tacrine and vaccines, serotoninergic syndrome and side effects of new antiepileptic drugs.

  18. Hormonal contraceptive methods and risk of HIV acquisition in women: a systematic review of epidemiological evidence.

    PubMed

    Polis, Chelsea B; Phillips, Sharon J; Curtis, Kathryn M; Westreich, Daniel J; Steyn, Petrus S; Raymond, Elizabeth; Hannaford, Philip; Turner, Abigail Norris

    2014-10-01

    Whether use of various types of hormonal contraception (HC) affect risk of HIV acquisition is a critical question for women's health. For this systematic review, we identified 22 studies published by January 15, 2014 which met inclusion criteria; we classified thirteen studies as having severe methodological limitations, and nine studies as "informative but with important limitations". Overall, data do not support an association between use of oral contraceptives and increased risk of HIV acquisition. Uncertainty persists regarding whether an association exists between depot-medroxyprogesterone acetate (DMPA) use and risk of HIV acquisition. Most studies suggested no significantly increased HIV risk with norethisterone enanthate (NET-EN) use, but when assessed in the same study, point estimates for NET-EN tended to be larger than for DMPA, though 95% confidence intervals overlapped substantially. No data have suggested significantly increased risk of HIV acquisition with use of implants, though data were limited. No data are available on the relationship between use of contraceptive patches, rings, or hormonal intrauterine devices and risk of HIV acquisition. Women choosing progestin-only injectable contraceptives such as DMPA or NET-EN should be informed of the current uncertainty regarding whether use of these methods increases risk of HIV acquisition, and like all women at risk of HIV, should be empowered to access and use condoms and other HIV preventative measures. Programs, practitioners, and women urgently need guidance on how to maximize health with respect to avoiding both unintended pregnancy and HIV given inconclusive or limited data for certain HC methods.

  19. Methods for estimation of radiation risk in epidemiological studies accounting for classical and Berkson errors in doses.

    PubMed

    Kukush, Alexander; Shklyar, Sergiy; Masiuk, Sergii; Likhtarov, Illya; Kovgan, Lina; Carroll, Raymond J; Bouville, Andre

    2011-02-16

    With a binary response Y, the dose-response model under consideration is logistic in flavor with pr(Y=1 | D) = R (1+R)(-1), R = λ(0) + EAR D, where λ(0) is the baseline incidence rate and EAR is the excess absolute risk per gray. The calculated thyroid dose of a person i is expressed as Dimes=fiQi(mes)/Mi(mes). Here, Qi(mes) is the measured content of radioiodine in the thyroid gland of person i at time t(mes), Mi(mes) is the estimate of the thyroid mass, and f(i) is the normalizing multiplier. The Q(i) and M(i) are measured with multiplicative errors Vi(Q) and ViM, so that Qi(mes)=Qi(tr)Vi(Q) (this is classical measurement error model) and Mi(tr)=Mi(mes)Vi(M) (this is Berkson measurement error model). Here, Qi(tr) is the true content of radioactivity in the thyroid gland, and Mi(tr) is the true value of the thyroid mass. The error in f(i) is much smaller than the errors in ( Qi(mes), Mi(mes)) and ignored in the analysis. By means of Parametric Full Maximum Likelihood and Regression Calibration (under the assumption that the data set of true doses has lognormal distribution), Nonparametric Full Maximum Likelihood, Nonparametric Regression Calibration, and by properly tuned SIMEX method we study the influence of measurement errors in thyroid dose on the estimates of λ(0) and EAR. The simulation study is presented based on a real sample from the epidemiological studies. The doses were reconstructed in the framework of the Ukrainian-American project on the investigation of Post-Chernobyl thyroid cancers in Ukraine, and the underlying subpolulation was artificially enlarged in order to increase the statistical power. The true risk parameters were given by the values to earlier epidemiological studies, and then the binary response was simulated according to the dose-response model.

  20. Epidemiology: Then and Now.

    PubMed

    Kuller, Lewis H

    2016-03-01

    Twenty-five years ago, on the 75th anniversary of the Johns Hopkins Bloomberg School of Public Health, I noted that epidemiologic research was moving away from the traditional approaches used to investigate "epidemics" and their close relationship with preventive medicine. Twenty-five years later, the role of epidemiology as an important contribution to human population research, preventive medicine, and public health is under substantial pressure because of the emphasis on "big data," phenomenology, and personalized medical therapies. Epidemiology is the study of epidemics. The primary role of epidemiology is to identify the epidemics and parameters of interest of host, agent, and environment and to generate and test hypotheses in search of causal pathways. Almost all diseases have a specific distribution in relation to time, place, and person and specific "causes" with high effect sizes. Epidemiology then uses such information to develop interventions and test (through clinical trials and natural experiments) their efficacy and effectiveness. Epidemiology is dependent on new technologies to evaluate improved measurements of host (genomics), epigenetics, identification of agents (metabolomics, proteomics), new technology to evaluate both physical and social environment, and modern methods of data collection. Epidemiology does poorly in studying anything other than epidemics and collections of numerators and denominators without specific hypotheses even with improved statistical methodologies.

  1. The INTERPHONE study: design, epidemiological methods, and description of the study population.

    PubMed

    Cardis, Elisabeth; Richardson, Lesley; Deltour, Isabelle; Armstrong, Bruce; Feychting, Maria; Johansen, Christoffer; Kilkenny, Monique; McKinney, Patricia; Modan, Baruch; Sadetzki, Siegal; Schüz, Joachim; Swerdlow, Anthony; Vrijheid, Martine; Auvinen, Anssi; Berg, Gabriele; Blettner, Maria; Bowman, Joseph; Brown, Julianne; Chetrit, Angela; Christensen, Helle Collatz; Cook, Angus; Hepworth, Sarah; Giles, Graham; Hours, Martine; Iavarone, Ivano; Jarus-Hakak, Avital; Klaeboe, Lars; Krewski, Daniel; Lagorio, Susanna; Lönn, Stefan; Mann, Simon; McBride, Mary; Muir, Kenneth; Nadon, Louise; Parent, Marie-Elise; Pearce, Neil; Salminen, Tiina; Schoemaker, Minouk; Schlehofer, Brigitte; Siemiatycki, Jack; Taki, Masao; Takebayashi, Toru; Tynes, Tore; van Tongeren, Martie; Vecchia, Paolo; Wiart, Joe; Woodward, Alistair; Yamaguchi, Naohito

    2007-01-01

    The very rapid worldwide increase in mobile phone use in the last decade has generated considerable interest in the possible health effects of exposure to radio frequency (RF) fields. A multinational case-control study, INTERPHONE, was set-up to investigate whether mobile phone use increases the risk of cancer and, more specifically, whether the RF fields emitted by mobile phones are carcinogenic. The study focused on tumours arising in the tissues most exposed to RF fields from mobile phones: glioma, meningioma, acoustic neurinoma and parotid gland tumours. In addition to a detailed history of mobile phone use, information was collected on a number of known and potential risk factors for these tumours. The study was conducted in 13 countries. Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden, and the UK using a common core protocol. This paper describes the study design and methods and the main characteristics of the study population. INTERPHONE is the largest case-control study to date investigating risks related to mobile phone use and to other potential risk factors for the tumours of interest and includes 2,765 glioma, 2,425 meningioma, 1,121 acoustic neurinoma, 109 malignant parotid gland tumour cases and 7,658 controls. Particular attention was paid to estimating the amount and direction of potential recall and participation biases and their impact on the study results.

  2. Statistical Reasoning and Methods in Epidemiology to Promote Individualized Health: In Celebration of the 100th Anniversary of the Johns Hopkins Bloomberg School of Public Health.

    PubMed

    Ogburn, Elizabeth L; Zeger, Scott L

    2016-03-01

    Epidemiology is concerned with determining the distribution and causes of disease. Throughout its history, epidemiology has drawn upon statistical ideas and methods to achieve its aims. Because of the exponential growth in our capacity to measure and analyze data on the underlying processes that define each person's state of health, there is an emerging opportunity for population-based epidemiologic studies to influence health decisions made by individuals in ways that take into account the individuals' characteristics, circumstances, and preferences. We refer to this endeavor as "individualized health." The present article comprises 2 sections. In the first, we describe how graphical, longitudinal, and hierarchical models can inform the project of individualized health. We propose a simple graphical model for informing individual health decisions using population-based data. In the second, we review selected topics in causal inference that we believe to be particularly useful for individualized health. Epidemiology and biostatistics were 2 of the 4 founding departments in the world's first graduate school of public health at Johns Hopkins University, the centennial of which we honor. This survey of a small part of the literature is intended to demonstrate that the 2 fields remain just as inextricably linked today as they were 100 years ago.

  3. Endodontic Epidemiology

    PubMed Central

    Shahravan, Arash; Haghdoost, Ali Akbar

    2014-01-01

    Epidemiology is the study of disease distribution and factors determining or affecting it. Likewise, endodontic epidemiology can be defined as the science of studying the distribution pattern and determinants of pulp and periapical diseases; specially apical periodontitis. Although different study designs have been used in endodontics, researchers must pay more attention to study designs with higher level of evidence such as randomized clinical trials. PMID:24688577

  4. Assessment of methods and results of reproductive occupational epidemiology: spontaneous abortions and malformations in the offspring of working women

    SciTech Connect

    Hemminki, K.; Axelson, O.; Niemi, M.L.; Ahlborg, G.

    1983-01-01

    Epidemiological studies relating occupational exposures of working women to spontaneous abortions and malformation are reviewed and some methodological considerations are presented. The reproductive epidemiology is less developed than epidemiology in general and seems to involve some specific problems. The exposures may be reported differently by the women depending on the outcome of the pregnancy; thus confirmation of exposure from an independent data source would be an asset. The types of occupational exposures of the women, suggested to carry a risk of spontaneous abortions, include anesthetic agents, laboratory work, copper smelting, soldering, and chemical sterilization using ethylene oxide and glutaraldehyde. Maternal employment in laboratories and exposure to solvents has been linked to a risk of congenital malformations in the offspring in five studies. Data on the teratogenic effects of anesthetic gases has been conflicting. In one study, employment in copper smelting was associated with malformations in the offspring.

  5. Prevalence and Epidemiologic Characteristics of FASD From Various Research Methods with an Emphasis on Recent In-School Studies

    ERIC Educational Resources Information Center

    May, Philip A.; Gossage, J. Phillip; Kalberg, Wendy O.; Robinson, Luther K.; Buckley, David; Manning, Melanie; Hoyme, H. Eugene

    2009-01-01

    Researching the epidemiology and estimating the prevalence of fetal alcohol syndrome (FAS) and other fetal alcohol spectrum disorders (FASD) for mainstream populations anywhere in the world has presented a challenge to researchers. Three major approaches have been used in the past: surveillance and record review systems, clinic-based studies, and…

  6. Evaluation of method for secondary DNA typing of Mycobacterium tuberculosis with pTBN12 in epidemiologic study of tuberculosis.

    PubMed

    Yang, Z; Chaves, F; Barnes, P F; Burman, W J; Koehler, J; Eisenach, K D; Bates, J H; Cave, M D

    1996-12-01

    Secondary fingerprinting of Mycobacterium tuberculosis DNA with a probe containing the polymorphic GC-rich repetitive sequence present in pTBN12 has been found to have greater discriminating power than does fingerprinting with the insertion sequence IS6110 for strains carrying few copies of IS6110. To validate the use of pTBN12 fingerprinting in the molecular epidemiology of tuberculosis, M. tuberculosis isolates from 67 patients in five states in the United States and in Spain were fingerprinted with both IS6110 and pTBN12. Epidemiologic links among the 67 patients were evaluated by patient interview and/or review of medical records. The 67 isolates had 5 IS6110 fingerprint patterns with two to five copies of IS6110 and 18 pTBN12 patterns, of which 10 were shared by more than 1 isolate. Epidemiologic links are consistently found among patients whose isolates had identical pTBN12 patterns, whereas no links were found among patients whose isolates had unique pTBN12 patterns. This suggests that pTBN12 fingerprinting is a useful tool to identify epidemiologically linked tuberculosis patients whose isolates have identical IS6110 fingerprints containing fewer than six fragments.

  7. Polygenic Epidemiology

    PubMed Central

    2016-01-01

    ABSTRACT Much of the genetic basis of complex traits is present on current genotyping products, but the individual variants that affect the traits have largely not been identified. Several traditional problems in genetic epidemiology have recently been addressed by assuming a polygenic basis for disease and treating it as a single entity. Here I briefly review some of these applications, which collectively may be termed polygenic epidemiology. Methodologies in this area include polygenic scoring, linear mixed models, and linkage disequilibrium scoring. They have been used to establish a polygenic effect, estimate genetic correlation between traits, estimate how many variants affect a trait, stratify cases into subphenotypes, predict individual disease risks, and infer causal effects using Mendelian randomization. Polygenic epidemiology will continue to yield useful applications even while much of the specific variation underlying complex traits remains undiscovered. PMID:27061411

  8. Molecular Epidemiology of Breast Cancer: Development and Validation of Acetylation Methods for Carcinogen-DNA Adduct Detection

    DTIC Science & Technology

    2001-10-01

    epidemiological studies, and determine adduct levels in relation to metabolizing gene polymorphisms . The originally proposed assay is novel because one uses a...carcinogenic mechanisms. Currently, many ongoing breast cancer studies are exploring risks related to genetic polymorphisms in these genes. Yet these...the surrogate tissue). Finally, in these subjects, we will perform assays for genetic polymorphisms , to assess the association of "at risk" genetic

  9. Molecular epidemiology of human hepatitis A virus defined by an antigen-capture polymerase chain reaction method.

    PubMed Central

    Jansen, R W; Siegl, G; Lemon, S M

    1990-01-01

    We describe an immunoaffinity-linked nucleic acid amplification system (antigen-capture/polymerase chain reaction, or AC/PCR) for detection of viruses in clinical specimens and its application to the study of the molecular epidemiology of a picornavirus, hepatitis A virus (HAV). Immunoaffinity capture of virus, synthesis of viral cDNA, and amplification of cDNA by a polymerase chain reaction (PCR) were carried out sequentially in a single reaction vessel. This approach simplified sample preparation and enhanced the specificity of conventional PCR. AC/PCR detected less than one cell culture infectious unit of virus in 80 microliters of sample. Sequencing of AC/PCR reaction products from 34 virus strains demonstrated remarkable conservation at the nucleotide level among most strains but revealed hitherto unsuspected genetic diversity among human isolates. Epidemiologically related strains were identical or closely related in sequence. Virus strains recovered from epidemics of hepatitis A in the United States and Germany were identical in sequence, providing evidence for a previously unrecognized epidemiologic link between these outbreaks. Images PMID:2158093

  10. Against Popperized epidemiology.

    PubMed

    Jacobsen, M

    1976-03-01

    The recommendation of Popper's philosophy of science should be adopted by epidemiologists is disputed. Reference is made to other authors who have shown that the most constructive elements in Popper's ideas have been advocated by earlier philosophers and have been used in epidemiology without abandoning inductive reasoning. It is argued that Popper's denigration of inductive methods is particularly harmful to epidemiology. Inductive reasoning and statistical inference play a key role in the science; it is suggested that unfamiliarity with these ideas contributes to widespread misunderstanding of the function of epidemiology. Attention is drawn to a common fallacy involving correlations between three random variables. The prevalence of the fallacy may be related to confusion between deductive and inductive logic.

  11. Digital Epidemiology

    PubMed Central

    Salathé, Marcel; Bengtsson, Linus; Bodnar, Todd J.; Brewer, Devon D.; Brownstein, John S.; Buckee, Caroline; Campbell, Ellsworth M.; Cattuto, Ciro; Khandelwal, Shashank; Mabry, Patricia L.; Vespignani, Alessandro

    2012-01-01

    Mobile, social, real-time: the ongoing revolution in the way people communicate has given rise to a new kind of epidemiology. Digital data sources, when harnessed appropriately, can provide local and timely information about disease and health dynamics in populations around the world. The rapid, unprecedented increase in the availability of relevant data from various digital sources creates considerable technical and computational challenges. PMID:22844241

  12. Comparison of pulsed-field gel electrophoresis & repetitive sequence-based PCR methods for molecular epidemiological studies of Escherichia coli clinical isolates

    PubMed Central

    Bae, Il Kwon; Kim, Juwon; Sun, Je Young Hannah; Jeong, Seok Hoon; Kim, Yong-Rok; Wang, Kang-Kyun; Lee, Kyungwon

    2014-01-01

    Background & objectives: PFGE, rep-PCR, and MLST are widely used to identify related bacterial isolates and determine epidemiologic associations during outbreaks. This study was performed to compare the ability of repetitive sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE) to determine the genetic relationships among Escherichia coli isolates assigned to various sequence types (STs) by two multilocus sequence typing (MLST) schemes. Methods: A total of 41 extended-spectrum β-lactamase- (ESBL-) and/or AmpC β-lactamase-producing E. coli clinical isolates were included in this study. MLST experiments were performed following the Achtman's MLST scheme and the Whittam's MLST scheme, respectively. Rep-PCR experiments were performed using the DiversiLab system. PFGE experiments were also performed. Results: A comparison of the two MLST methods demonstrated that these two schemes yielded compatible results. PFGE correctly segregated E. coli isolates belonging to different STs as different types, but did not group E. coli isolates belonging to the same ST in the same group. Rep-PCR accurately grouped E. coli isolates belonging to the same ST together, but this method demonstrated limited ability to discriminate between E. coli isolates belonging to different STs. Interpretation & conclusions: These results suggest that PFGE would be more effective when investigating outbreaks in a limited space, such as a specialty hospital or an intensive care unit, whereas rep-PCR should be used for nationwide or worldwide epidemiology studies. PMID:25579152

  13. Rapid species identification and epidemiological analysis of carbapenem-resistant Acinetobacter spp. by a PCR-based open reading frame typing method.

    PubMed

    Yamada, Yuki; Endo, Kentaro; Sawase, Kaori; Anetai, Marie; Narita, Kazuya; Hatakeyama, Yuji; Ishifuji, Katsunori; Kurota, Makiko; Suwabe, Akira

    2016-09-01

    The spread of carbapenem-resistant Acinetobacter spp. has become a global problem. In this study, 18 carbapenem-resistant Acinetobacter calcoaceticus-baumannii (ACB) complexes, identified using a conventional biochemical method at our hospital during 2004-2013, were studied for species identification and epidemiological analyses. Species identification was performed using matrix-assisted laser desorption ionization-time-of-flight MS, a partial sequence analysis of rpoB and a PCR-based ORF typing (POT) method. The POT method can not only identify the species of ACB complexes but also simultaneously determine the international epidemic clones and the genetic identities of Acinetobacterbaumannii in several hours. Carbapenem resistance gene detection by PCR, molecular epidemiological analysis by PFGE and Pasteur Institute multilocus sequence typing (MLST) analysis were performed. All three methods identified 18 isolates as A. baumannii (n=10), Acinetobacterpittii (n=4) and Acinetobacternosocomialis (n=4). A metallo-β-lactamase gene in all strains of A. pittii and A. nosocomialis and an ISAba1 gene in the upstream of the blaOXA-51-like gene in eight strains of A. baumannii were detected, respectively, as carbapenemase-related genes. Results from PFGE demonstrated that nine strains of A. baumannii were closely related genetically. Results of MLST analysis showed that A. baumannii are classifiable to sequence type 2. These results were consistent with those obtained using the POT method. This POT method can easily and rapidly identify the international epidemic clones and the identities of A. baumannii. It can be a useful tool for infection control.

  14. Molecular epidemiology and a loop-mediated isothermal amplification method for diagnosis of infection with rabies virus in Zambia.

    PubMed

    Muleya, Walter; Namangala, Boniface; Mweene, Aaron; Zulu, Luke; Fandamu, Paul; Banda, Douglas; Kimura, Takashi; Sawa, Hirofumi; Ishii, Akihiro

    2012-01-01

    The National Livestock Epidemiology and Information Center (NALEIC) in Zambia reported over 132 cases of canine rabies diagnosed by the direct fluorescent antibody test (DFAT) from 2004 to 2009. In this study, the lineage of rabies virus (RABV) in Zambia was determined by phylogenetic analysis of the nucleoprotein (N) and glycoprotein (G) gene sequences. Total RNA was extracted from 87-DFAT brain specimens out of which only 35 (40%) were positive on nested reverse transcription polymerase chain reaction (RT-PCR) for each gene, and 26 being positive for both genes. Positive specimens for the N (n=33) and G (n=35) genes were used for phylogenetic analysis. Phylogenetic analysis of the N gene showed two phylogenetic clusters in Zambia belonging to the Africa 1b lineage present in eastern and southern Africa. While one cluster exclusively comprised Zambian strains, the other was more heterogeneous regarding the RABV origins and included strains from Tanzania, Mozambique and Zambia. Phylogenetic analysis of the G gene revealed similar RABV strains in different hosts and regions of Zambia. We designed primers for reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay from the consensus sequence of the N gene in an attempt to improve the molecular diagnosis of RABV in Zambia. The specificity and reproducibility of the RT-LAMP assay was confirmed with actual clinical specimens. Therefore, the RT-LAMP assay presented in this study may prove to be useful for routine diagnosis of rabies in Zambia.

  15. A Review of the Epidemiological Methods Used to Investigate the Health Impacts of Air Pollution around Major Industrial Areas

    PubMed Central

    Pascal, Laurence; Bidondo, Marie-Laure; Cochet, Amandine; Sarter, Hélène; Stempfelet, Morgane; Wagner, Vérène

    2013-01-01

    We performed a literature review to investigate how epidemiological studies have been used to assess the health consequences of living in the vicinity of industries. 77 papers on the chronic effects of air pollution around major industrial areas were reviewed. Major health themes were cancers (27 studies), morbidity (25 studies), mortality (7 studies), and birth outcome (7 studies). Only 3 studies investigated mental health. While studies were available from many different countries, a majority of papers came from the United Kingdom, Italy, and Spain. Several studies were motivated by concerns from the population or by previous observations of an overincidence of cases. Geographical ecological designs were largely used for studying cancer and mortality, including statistical designs to quantify a relationship between health indicators and exposure. Morbidity was frequently investigated through cross-sectional surveys on the respiratory health of children. Few multicenter studies were performed. In a majority of papers, exposed areas were defined based on the distance to the industry and were located from <2 km to >20 km from the plants. Improving the exposure assessment would be an asset to future studies. Criteria to include industries in multicenter studies should be defined. PMID:23818910

  16. A review of the epidemiological methods used to investigate the health impacts of air pollution around major industrial areas.

    PubMed

    Pascal, Mathilde; Pascal, Laurence; Bidondo, Marie-Laure; Cochet, Amandine; Sarter, Hélène; Stempfelet, Morgane; Wagner, Vérène

    2013-01-01

    We performed a literature review to investigate how epidemiological studies have been used to assess the health consequences of living in the vicinity of industries. 77 papers on the chronic effects of air pollution around major industrial areas were reviewed. Major health themes were cancers (27 studies), morbidity (25 studies), mortality (7 studies), and birth outcome (7 studies). Only 3 studies investigated mental health. While studies were available from many different countries, a majority of papers came from the United Kingdom, Italy, and Spain. Several studies were motivated by concerns from the population or by previous observations of an overincidence of cases. Geographical ecological designs were largely used for studying cancer and mortality, including statistical designs to quantify a relationship between health indicators and exposure. Morbidity was frequently investigated through cross-sectional surveys on the respiratory health of children. Few multicenter studies were performed. In a majority of papers, exposed areas were defined based on the distance to the industry and were located from <2 km to >20 km from the plants. Improving the exposure assessment would be an asset to future studies. Criteria to include industries in multicenter studies should be defined.

  17. Melanocortin-1 receptor, skin cancer and phenotypic characteristics (M-SKIP) project: study design and methods for pooling results of genetic epidemiological studies

    PubMed Central

    2012-01-01

    Background For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia. Design and methods Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling. Discussion Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields. PMID:22862891

  18. The Global Enteric Multicenter Study (GEMS) of Diarrheal Disease in Infants and Young Children in Developing Countries: Epidemiologic and Clinical Methods of the Case/Control Study

    PubMed Central

    Kotloff, Karen L.; Blackwelder, William C.; Nasrin, Dilruba; Nataro, James P.; Farag, Tamer H.; van Eijk, Annemieke; Adegbola, Richard A.; Alonso, Pedro L.; Breiman, Robert F.; Golam Faruque, Abu Syed; Saha, Debasish; Sow, Samba O.; Sur, Dipika; Zaidi, Anita K. M.; Biswas, Kousick; Panchalingam, Sandra; Clemens, John D.; Cohen, Dani; Glass, Roger I.; Mintz, Eric D.; Sommerfelt, Halvor; Levine, Myron M.

    2012-01-01

    Background. Diarrhea is a leading cause of illness and death among children aged <5 years in developing countries. This paper describes the clinical and epidemiological methods used to conduct the Global Enteric Multicenter Study (GEMS), a 3-year, prospective, age-stratified, case/control study to estimate the population-based burden, microbiologic etiology, and adverse clinical consequences of acute moderate-to-severe diarrhea (MSD) among a censused population of children aged 0–59 months seeking care at health centers in sub-Saharan Africa and South Asia. Methods. GEMS was conducted at 7 field sites, each serving a population whose demography and healthcare utilization practices for childhood diarrhea were documented. We aimed to enroll 220 MSD cases per year from selected health centers serving each site in each of 3 age strata (0–11, 12–23, and 24–59 months), along with 1–3 matched community controls. Cases and controls supplied clinical, epidemiologic, and anthropometric data at enrollment and again approximately 60 days later, and provided enrollment stool specimens for identification and characterization of potential diarrheal pathogens. Verbal autopsy was performed if a child died. Analytic strategies will calculate the fraction of MSD attributable to each pathogen and the incidence, financial costs, nutritional consequences, and case fatality overall and by pathogen. Conclusions. When completed, GEMS will provide estimates of the incidence, etiology, and outcomes of MSD among infants and young children in sub-Saharan Africa and South Asia. This information can guide development and implementation of public health interventions to diminish morbidity and mortality from diarrheal diseases. PMID:23169936

  19. Epidemiology of epilepsy.

    PubMed

    Abramovici, S; Bagić, A

    2016-01-01

    Modern epidemiology of epilepsy maximizes the benefits of advanced diagnostic methods and sophisticated techniques for case ascertainment in order to increase the diagnostic accuracy and representativeness of the cases and cohorts studied, resulting in better comparability of similarly performed studies. Overall, these advanced epidemiologic methods are expected to yield a better understanding of diverse risk factors, high-risk populations, seizure triggers, multiple and poorly understood causes of epilepsy, including the increasing and complex role of genetics, and establish the natural course of treated and untreated epilepsy and syndromes - all of which form the foundation of an attempt to prevent epileptogenesis as the primary prophylaxis of epilepsy. Although data collection continues to improve, epidemiologists still need to overcome definition and coding variability, insufficient documentation, as well as the interplay of socioeconomic factors and stigma. As most of the 65-70 million people with epilepsy live outside of resource-rich countries, extensive underdiagnosis, misdiagnosis, and undertreatment are likely. Epidemiology will continue to provide the necessary information to the medical community, public, and regulators as the foundation for improved health policies, targeted education, and advanced measures of prevention and prognostication of the most common severe brain disorder.

  20. [Schistosomiasis epidemiology (author's transl)].

    PubMed

    Picq, J J; Roux, J

    1980-01-01

    Schistosomiasis are, with three hundred million of infested people, the second world endemy, after malaria. For each of the four species, the distribution areas, the life cycle and the main epidemiological features are recalled in the first chapter. In the five following chapters, the authors consider the human or animal reservoirs of virus, the importance of these diseases towards public health, the gasteropod molluscs acting as intermediate hosts, and the problems of immunity in man. The concepts of "schistosomian infection" and "schistosomian disease" are exposed as well as the differences affecting the various strains of schistosomes and snails intermediate hosts. The authors emphasize the value of quantitative parasitological techniques and sero-immunological methods for epidemiological surveys. They underline the difficulties met in the evaluation of the effect of these diseases upon public health. The main causes inducing the duration of the endemy and those responsible for its extension are studied. The value of mathematic patterns is briefly discussed. Quantitative data compiled through epidemiological surveys should improve the use of the various means presently available for controling schistosomiasis.

  1. Allergic contact dermatitis: epidemiology, molecular mechanisms, in vitro methods and regulatory aspects. Current knowledge assembled at an international workshop at BfR, Germany.

    PubMed

    Peiser, M; Tralau, T; Heidler, J; Api, A M; Arts, J H E; Basketter, D A; English, J; Diepgen, T L; Fuhlbrigge, R C; Gaspari, A A; Johansen, J D; Karlberg, A T; Kimber, I; Lepoittevin, J P; Liebsch, M; Maibach, H I; Martin, S F; Merk, H F; Platzek, T; Rustemeyer, T; Schnuch, A; Vandebriel, R J; White, I R; Luch, A

    2012-03-01

    Contact allergies are complex diseases, and one of the important challenges for public health and immunology. The German 'Federal Institute for Risk Assessment' hosted an 'International Workshop on Contact Dermatitis'. The scope of the workshop was to discuss new discoveries and developments in the field of contact dermatitis. This included the epidemiology and molecular biology of contact allergy, as well as the development of new in vitro methods. Furthermore, it considered regulatory aspects aiming to reduce exposure to contact sensitisers. An estimated 15-20% of the general population suffers from contact allergy. Workplace exposure, age, sex, use of consumer products and genetic predispositions were identified as the most important risk factors. Research highlights included: advances in understanding of immune responses to contact sensitisers, the importance of autoxidation or enzyme-mediated oxidation for the activation of chemicals, the mechanisms through which hapten-protein conjugates are formed and the development of novel in vitro strategies for the identification of skin-sensitising chemicals. Dendritic cell cultures and structure-activity relationships are being developed to identify potential contact allergens. However, the local lymph node assay (LLNA) presently remains the validated method of choice for hazard identification and characterisation. At the workshop the use of the LLNA for regulatory purposes and for quantitative risk assessment was also discussed.

  2. [A method for studying social security records in epidemiology. Use in a study on the prognosis of chronic bronchitis (author's transl)].

    PubMed

    Kauffmann, F; Bahi, J; Brille, D

    1976-01-01

    A method is presented to study, in an epidemiological research, the social security records. This study is based upon records of workers affiliated to the french social security general system. To obtain data which may be compared, it was necessary to take the legislation as a basis; this legislation gives the data which must be in the records. A study of laws and rules has been done to find out these data in the medical record and in the administrative one. A questionnaire is presented. This basic questionnaire should be modified according to the precise objectives of each study and to the characteristics of the population sample. To illustrate this method, some results of a study of chronic bronchitis risk factors are presented in the second part. These results concern 950 men, born in France, aged 30 to 59 in 1960 an still alive in 1972. The study of the long reductions of the ability to work, happened from 1960 to 1971, confirm the disabling character of the group "chronic bronchitis, asthma, emphysema, respiratory insufficiency" which follows immediately cardiovascular and rheumatic diseases. The total number of beneficiaries of the social security is already very important and the whole population will be soon concerned. The use of the social security records as data source could give very interesting informations about morbidity. So, it is possible to study representative samples of the general population or of some particular groups, which has up to now, been done only in a slight extent.

  3. International Evaluation of MIC Distributions and Epidemiological Cutoff Value (ECV) Definitions for Fusarium Species Identified by Molecular Methods for the CLSI Broth Microdilution Method

    PubMed Central

    Colombo, A. L.; Cordoba, S.; Dufresne, P. J.; Fuller, J.; Ghannoum, M.; Gonzalez, G. M.; Guarro, J.; Kidd, S. E.; Melhem, T. M. S. C.; Pelaez, T.; Pfaller, M. A.; Szeszs, M. W.; Takahaschi, J. P.; Wiederhold, N. P.; Turnidge, J.

    2015-01-01

    The CLSI epidemiological cutoff values (ECVs) of antifungal agents are available for various Candida spp., Aspergillus spp., and the Mucorales. However, those categorical endpoints have not been established for Fusarium spp., mostly due to the difficulties associated with collecting sufficient CLSI MICs for clinical isolates identified according to the currently recommended molecular DNA-PCR-based identification methodologies. CLSI MIC distributions were established for 53 Fusarium dimerum species complex (SC), 10 F. fujikuroi, 82 F. proliferatum, 20 F. incarnatum-F. equiseti SC, 226 F. oxysporum SC, 608 F. solani SC, and 151 F. verticillioides isolates originating in 17 laboratories (in Argentina, Australia, Brazil, Canada, Europe, Mexico, and the United States). According to the CLSI guidelines for ECV setting, ECVs encompassing ≥97.5% of pooled statistically modeled MIC distributions were as follows: for amphotericin B, 4 μg/ml (F. verticillioides) and 8 μg/ml (F. oxysporum SC and F. solani SC); for posaconazole, 2 μg/ml (F. verticillioides), 8 μg/ml (F. oxysporum SC), and 32 μg/ml (F. solani SC); for voriconazole, 4 μg/ml (F. verticillioides), 16 μg/ml (F. oxysporum SC), and 32 μg/ml (F. solani SC); and for itraconazole, 32 μg/ml (F. oxysporum SC and F. solani SC). Insufficient data precluded ECV definition for the other species. Although these ECVs could aid in detecting non-wild-type isolates with reduced susceptibility to the agents evaluated, the relationship between molecular mechanisms of resistance (gene mutations) and MICs still needs to be investigated for Fusarium spp. PMID:26643334

  4. Infectious Agents and Cancer Epidemiology Research Webinar Series

    Cancer.gov

    Infectious Agents and Cancer Epidemiology Research Webinar Series highlights emerging and cutting-edge research related to infection-associated cancers, shares scientific knowledge about technologies and methods, and fosters cross-disciplinary discussions on infectious agents and cancer epidemiology.

  5. Classification of personal exposure to radio frequency electromagnetic fields (RF-EMF) for epidemiological research: Evaluation of different exposure assessment methods.

    PubMed

    Frei, Patrizia; Mohler, Evelyn; Bürgi, Alfred; Fröhlich, Jürg; Neubauer, Georg; Braun-Fahrländer, Charlotte; Röösli, Martin

    2010-10-01

    The use of personal exposure meters (exposimeters) has been recommended for measuring personal exposure to radio frequency electromagnetic fields (RF-EMF) from environmental far-field sources in everyday life. However, it is unclear to what extent exposimeter readings are affected by measurements taken when personal mobile and cordless phones are used. In addition, the use of exposimeters in large epidemiological studies is limited due to high costs and large effort for study participants. In the current analysis we aimed to investigate the impact of personal phone use on exposimeter readings and to evaluate different exposure assessment methods potentially useful in epidemiological studies. We collected personal exposimeter measurements during one week and diary data from 166 study participants. Moreover, we collected spot measurements in the participants' bedrooms and data on self-estimated exposure, assessed residential exposure to fixed site transmitters by calculating the geo-coded distance and mean RF-EMF from a geospatial propagation model, and developed an exposure prediction model based on the propagation model and exposure relevant behavior. The mean personal exposure was 0.13 mW/m(2), when measurements during personal phone calls were excluded and 0.15 mW/m(2), when such measurements were included. The Spearman correlation with personal exposure (without personal phone calls) was 0.42 (95%-CI: 0.29 to 0.55) for the spot measurements, -0.03 (95%-CI: -0.18 to 0.12) for the geo-coded distance, 0.28 (95%-CI: 0.14 to 0.42) for the geospatial propagation model, 0.50 (95%-CI: 0.37 to 0.61) for the full exposure prediction model and 0.06 (95%-CI: -0.10 to 0.21) for self-estimated exposure. In conclusion, personal exposure measured with exposimeters correlated best with the full exposure prediction model and spot measurements. Self-estimated exposure and geo-coded distance turned out to be poor surrogates for personal exposure.

  6. Methods and Descriptive Epidemiology of Services Provided by Athletic Trainers in High Schools: The National Athletic Treatment, Injury and Outcomes Network Study

    PubMed Central

    Kerr, Zachary Y.; Dompier, Thomas P.; Dalton, Sara L.; Miller, Sayers John; Hayden, Ross; Marshall, Stephen W.

    2015-01-01

    Context Research is limited on the extent and nature of the care provided by athletic trainers (ATs) to student-athletes in the high school setting. Objective To describe the methods of the National Athletic Treatment, Injury and Outcomes Network (NATION) project and provide the descriptive epidemiology of AT services for injury care in 27 high school sports. Design Descriptive epidemiology study. Setting Athletic training room (ATR) visits and AT services data collected in 147 high schools from 26 states. Patients or Other Participants High school student-athletes participating in 13 boys' sports and 14 girls' sports during the 2011−2012 through 2013−2014 academic years. Main Outcome Measure(s) The number of ATR visits and individual AT services, as well as the mean number of ATR visits (per injury) and AT services (per injury and ATR visit) were calculated by sport and for time-loss (TL) and non–time-loss (NTL) injuries. Results Over the 3-year period, 210 773 ATR visits and 557 381 AT services were reported for 50 604 injuries. Most ATR visits (70%) were for NTL injuries. Common AT services were therapeutic activities or exercise (45.4%), modalities (18.6%), and AT evaluation and reevaluation (15.9%), with an average of 4.17 ± 6.52 ATR visits and 11.01 ± 22.86 AT services per injury. Compared with NTL injuries, patients with TL injuries accrued more ATR visits (7.76 versus 3.47; P < .001) and AT services (18.60 versus 9.56; P < .001) per injury. An average of 2.24 ± 1.33 AT services were reported per ATR visit. Compared with TL injuries, NTL injuries had a larger average number of AT services per ATR visit (2.28 versus 2.05; P < .001). Conclusions These findings highlight the broad spectrum of care provided by ATs to high school student-athletes and demonstrate that patients with NTL injuries require substantial amounts of AT services. PMID:26678290

  7. The American Thoracic Society methods in epidemiologic, clinical, and operations research program. A research capacity-building program in low- and middle-income countries.

    PubMed

    Buist, A Sonia; Parry, Vivienne

    2013-08-01

    Respiratory diseases are a major cause of morbidity and mortality worldwide. The greatest impact of many of these diseases is felt in low- and middle-income countries, but their control and management is hampered by lack of accurate estimates of their prevalence, risk factors, and distribution, and knowledge of the social and cultural setting in which they occur. Providing enough information for cost-effective response to respiratory diseases requires research by trained investigators and public health personnel. The American Thoracic Society (ATS) Methods in Epidemiologic, Clinical, and Operations Research (MECOR) Program was launched in 1994 to provide a sustainable means of increasing local and national research capacity aimed at addressing this need. As of March 2013, approximately 1,015 students have completed at least one level of the training program. Post-MECOR, 64% of participants have published a medical paper, 79% have presented at a scientific or academic meeting, 51% have submitted a research protocol for funding, and 42% have had one funded. One-quarter have been awarded an academic or clinical fellowship, and 78% reported that MECOR had made a significant or extremely important contribution to their professional life and accomplishments. Future challenges include funding, recruitment of local faculty, helping to build the research infrastructure in MECOR countries, and providing ongoing mentoring for research.

  8. A New Method to Predict the Epidemiology of Fungal Keratitis by Monitoring the Sales Distribution of Antifungal Eye Drops in Brazil

    PubMed Central

    Ibrahim, Marlon Moraes; de Angelis, Rafael; Lima, Acacio Souza; Viana de Carvalho, Glauco Dreyer; Ibrahim, Fuad Moraes; Malki, Leonardo Tannus; de Paula Bichuete, Marina; de Paula Martins, Wellington; Rocha, Eduardo Melani

    2012-01-01

    Purpose Fungi are a major cause of keratitis, although few medications are licensed for their treatment. The aim of this study is to observe the variation in commercialisation of antifungal eye drops, and to predict the seasonal distribution of fungal keratitis in Brazil. Methods Data from a retrospective study of antifungal eye drops sales from the only pharmaceutical ophthalmologic laboratory, authorized to dispense them in Brazil (Opthalmos) were gathered. These data were correlated with geographic and seasonal distribution of fungal keratitis in Brazil between July 2002 and June 2008. Results A total of 26,087 antifungal eye drop units were sold, with a mean of 2.3 per patient. There was significant variation in antifungal sales during the year (p<0.01). A linear regression model displayed a significant association between reduced relative humidity and antifungal drug sales (R2 = 0.17,p<0.01). Conclusions Antifungal eye drops sales suggest that there is a seasonal distribution of fungal keratitis. A possible interpretation is that the third quarter of the year (a period when the climate is drier), when agricultural activity is more intense in Brazil, suggests a correlation with a higher incidence of fungal keratitis. A similar model could be applied to other diseases, that are managed with unique, or few, and monitorable medications to predict epidemiological aspects. PMID:22457787

  9. Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary (STROBE-Vet) Statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-12-01

    The reporting of observational studies in veterinary research presents many challenges that often are not adequately addressed in published reporting guidelines. A consensus meeting of experts was organized to develop an extension of the STROBE statement to address observational studies in veterinary medicine with respect to animal health, animal production, animal welfare and food safety outcomes. The consensus meeting was held 11-13 May 2014 in Mississauga, Ontario, Canada. Seventeen experts from North America, Europe and Australia attended the meeting. The experts were epidemiologists and biostatisticians, many of whom hold or have held editorial positions with relevant journals. Prior to the meeting, 19 experts completed a survey about whether they felt any of the 22 items of the STROBE statement should be modified and whether items should be added to address unique issues related to observational studies in animal species with health, production, welfare or food safety outcomes. At the meeting, the participants were provided with the survey responses and relevant literature concerning the reporting of veterinary observational studies. During the meeting, each STROBE item was discussed to determine whether or not re-wording was recommended, and whether additions were warranted. Anonymous voting was used to determine whether there was consensus for each item change or addition. The consensus was that six items needed no modifications or additions. Modifications or additions were made to the STROBE items numbered as follows: 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations) and 22 (funding). Published literature was not always available to support modification to, or inclusion of, an item. The methods and processes used in the

  10. International Lymphoma Epidemiology Consortium

    Cancer.gov

    The InterLymph Consortium, or formally the International Consortium of Investigators Working on Non-Hodgkin's Lymphoma Epidemiologic Studies, is an open scientific forum for epidemiologic research in non-Hodgkin's lymphoma.

  11. Epidemiology of Alcoholism.

    ERIC Educational Resources Information Center

    Helzer, John E.

    1987-01-01

    Reviews the application of epidemiology to alcoholism. Discusses measurement and diagnostic issues and reviews studies of the prevalence of alcoholism, its risk factors, and the contributions of epidemiology to our knowledge of treatment and prevention. (Author/KS)

  12. Epidemiological Cutoff Values for Fluconazole, Itraconazole, Posaconazole, and Voriconazole for Six Candida Species as Determined by the Colorimetric Sensititre YeastOne Method

    PubMed Central

    Pemán, Javier; Iñiguez, Carmen; Hervás, David; Lopez-Hontangas, Jose L.; Pina-Vaz, Cidalia; Camarena, Juan J.; Campos-Herrero, Isolina; García-García, Inmaculada; García-Tapia, Ana M.; Guna, Remedios; Merino, Paloma; Pérez del Molino, Luisa; Rubio, Carmen; Suárez, Anabel

    2013-01-01

    In the absence of clinical breakpoints (CBP), epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of susceptibility tests. Sensititre YeastOne (SYO) is a widely used method to determine susceptibility of Candida spp. to antifungal agents. The CLSI CBP have been established, but not for the SYO method. The ECVs for four azoles, obtained using MIC distributions determined by the SYO method, were calculated via five methods (three statistical methods and based on the MIC50 and modal MIC). Respectively, the median ECVs (in mg/liter) of the five methods for fluconazole, itraconazole, posaconazole, and voriconazole (in parentheses: the percentage of isolates inhibited by MICs equal to or less than the ECVs; the number of isolates tested) were as follows: 2 (94.4%; 944), 0.5 (96.7%; 942), 0.25 (97.6%; 673), and 0.06 (96.7%; 849) for Candida albicans; 4 (86.1%; 642), 0.5 (99.4%; 642), 0.12 (93.9%; 392), and 0.06 (86.9%; 559) for C. parapsilosis; 8 (94.9%; 175), 1 (93.7%; 175), 2 (93.6%; 125), and 0.25 (90.4%; 167) for C. tropicalis; 128 (98.6%; 212), 4 (95.8%; 212), 4 (96.0%; 173), and 2 (98.5; 205) for C. glabrata; 256 (100%; 53), 1 (98.1%; 53), 1 (100%; 33), and 1 (97.9%; 48) for C. krusei; 4 (89.2%; 93), 0.5 (100%; 93), 0.25 (100%; 33), and 0.06 (87.7%; 73) for C. orthopsilosis. All methods included ≥94% of isolates and yielded similar ECVs (within 1 dilution). These ECVs would be suitable for monitoring emergence of isolates with reduced susceptibility by using the SYO method. PMID:23761155

  13. Restriction endonuclease analysis of clinical Pseudomonas aeruginosa strains: useful epidemiologic data from a simple and rapid method.

    PubMed Central

    Maher, W E; Kobe, M; Fass, R J

    1993-01-01

    Newer genetic techniques have replaced phenotypic methods of subtyping Pseudomonas aeruginosa strains. Widespread application of newer methodologies, however, may be limited by technologic complexity and the cost of equipment. We conducted restriction endonuclease analysis (REA) of sheared genomic DNAs from 48 clinical P. aeruginosa strains using the enzyme SalI and electrophoresis in horizontal, low-concentration (0.3 to 0.6%) agarose gels. Each REA profile consisted of a smear of lower-molecular-mass bands as well as a countable number of well-resolved bands in the 8.3- to 48.5-kbp range which could easily be compared when isolates were run side-by-side on the same gel. In general, the REA patterns of strains recovered from different patients differed by at least seven bands, and those of serial isolates from individual patients were identical or differed by, at most, two bands over this 8.3- to 48.5-kbp range. REA of strains already subtyped by field inversion gel electrophoresis revealed that the two techniques generally paralleled each other. Overall, some unrelated strains had similar REA profiles, but the relative simplicity and low cost of the approach coupled with the ability to demonstrate differences between most unrelated strains should make this type of REA an attractive first step in the investigation of institutional P. aeruginosa problems. Images PMID:8391021

  14. Assessing health impacts in complex eco-epidemiological settings in the humid tropics: Advancing tools and methods

    SciTech Connect

    Winkler, Mirko S.; Divall, Mark J.; Krieger, Gary R.; Balge, Marci Z.; Singer, Burton H.; Utzinger, Juerg

    2010-01-15

    In the developing world, large-scale projects in the extractive industry and natural resources sectors are often controversial and associated with long-term adverse health consequences to local communities. In many industrialised countries, health impact assessment (HIA) has been institutionalized for the mitigation of anticipated negative health effects while enhancing the benefits of projects, programmes and policies. However, in developing country settings, relatively few HIAs have been performed. Hence, more HIAs with a focus on low- and middle-income countries are needed to advance and refine tools and methods for impact assessment and subsequent mitigation measures. We present a promising HIA approach, developed within the frame of a large gold-mining project in the Democratic Republic of the Congo. The articulation of environmental health areas, the spatial delineation of potentially affected communities and the use of a diversity of sources to obtain quality baseline health data are utilized for risk profiling. We demonstrate how these tools and data are fed into a risk analysis matrix, which facilitates ranking of potential health impacts for subsequent prioritization of mitigation strategies. The outcomes encapsulate a multitude of environmental and health determinants in a systematic manner, and will assist decision-makers in the development of mitigation measures that minimize potential adverse health effects and enhance positive ones.

  15. Molecular Epidemiology of Leptospirosis in Northern Iran by Nested Polymerase Chain Reaction/Restriction Fragment Length Polymorphism and Sequencing Methods

    PubMed Central

    Zakeri, Sedigheh; Sepahian, Neda; Afsharpad, Mandana; Esfandiari, Behzad; Ziapour, Peyman; Djadid, Navid D.

    2010-01-01

    This study was conducted to investigate the prevalence of Leptospira species in Mazandaran Province of Iran by using nested polymerase chain reaction (PCR)/restriction fragment length polymorphism (RFLP) methods and sequencing analysis. Blood samples (n = 119) were collected from humans suspected of having leptospirosis from different parts of the province in 2007. By using an indirect immunofluorescent antibody test (IFAT), we determined that 35 (29.4%) of 119 suspected cases had leptospiral antibody titers ≥ 1:80, which confirmed the diagnosis of leptospirosis. Nested PCR assay also determined that 60 (50.4%) of 119 samples showed Leptospira infection. Furthermore, 44 (73.3%) of 60 confirmed leptospirosis amplified products were subjected to sequencing analysis. Sequence alignment identified L. interrogans, L. kirschneri, and L. wolffii species. All positive cases diagnosed by IFAT or PCR were in patients who reported contact with animals, high-risk occupational activities, and exposure to contaminated water. Therefore, it is important to increase attention about this disease among physicians and to strengthen laboratory capacity for its diagnosis in infected patients in Iran. PMID:20439973

  16. SU-D-16A-01: A Novel Method to Estimate Normal Tissue Dose for Radiotherapy Patients to Support Epidemiologic Studies of Second Cancer Risk

    SciTech Connect

    Lee, C; Jung, J; Pelletier, C; Kim, J; Lee, C

    2014-06-01

    Purpose: Patient cohort of second cancer study often involves radiotherapy patients with no radiological images available: We developed methods to construct a realistic surrogate anatomy by using computational human phantoms. We tested this phantom images both in a commercial treatment planning system (Eclipse) and a custom Monte Carlo (MC) transport code. Methods: We used a reference adult male phantom defined by International Commission on Radiological Protection (ICRP). The hybrid phantom which was originally developed in Non-Uniform Rational B-Spline (NURBS) and polygon mesh format was converted into more common medical imaging format. Electron density was calculated from the material composition of the organs and tissues and then converted into DICOM format. The DICOM images were imported into the Eclipse system for treatment planning, and then the resulting DICOM-RT files were imported into the MC code for MC-based dose calculation. Normal tissue doses were calculation in Eclipse and MC code for an illustrative prostate treatment case and compared to each other. Results: DICOM images were generated from the adult male reference phantom. Densities and volumes of selected organs between the original phantom and ones represented within Eclipse showed good agreements, less than 0.6%. Mean dose from Eclipse and MC code match less than 7%, whereas maximum and minimum doses were different up to 45%. Conclusion: The methods established in this study will be useful for the reconstruction of organ dose to support epidemiological studies of second cancer in cancer survivors treated by radiotherapy. We also work on implementing body size-dependent computational phantoms to better represent patient's anatomy when the height and weight of patients are available.

  17. Epidemiology, Science as Inquiry and Scientific Literacy

    ERIC Educational Resources Information Center

    Kaelin, Mark; Huebner, Wendy

    2003-01-01

    The recent worldwide SARS outbreak has put the science of epidemiology into the headlines once again. Epidemiology is "... the study of the distribution and the determinants of health-related states or events and the application of these methods to the control of health problems" (Gordis 2000). In this context, the authors have developed a…

  18. Assessing the Epidemiological Data and Management Methods of Body Packers Admitted to a Referral Center in Iran.

    PubMed

    Alipour-Faz, Athena; Shadnia, Shahin; Mirhashemi, Seyyed Hadi; Peyvandi, Maryam; Oroei, Mahbobeh; Shafagh, Omid; Peyvandi, Hassan; Peyvandi, Ali Asghar

    2016-05-01

    The incidence of smuggling and transporting illegal substances by internal concealment, also known as body packing, is on the rise. The clinical approach to such patients has been changed significantly over the past 2 decades. However, despite a recorded increase in body packing in general, there are controversies in the management of these patients. We aimed to gather data regarding the demographic characteristics, treatment, and outcome of body packers, which were that referred to Loghman Hakim Hospital, Tehran, Iran.The data of all body packers admitted to Loghman Hakim Hospital during 2010 to 2014 were evaluated retrospectively. Data regarding the demographic characteristics of the patients, findings of clinical imaging, treatment, and outcome were recorded.In this study, 175 individuals with a mean age of 31 ± 10 years were assessed. The most common concealed substances were crack (37%), crystal (17%), opium (13%), and heroin (6%). According to the results of surgery and imaging (abdominal radiography or computed tomography), the most common place for concealment was stomach in 33.3% and 12% of cases, respectively. Imaging findings were normal in 18% of the individuals. Forty-eight (27%) patients underwent surgery. The main indications for surgery were clinical manifestations of toxicity (79%) and obstruction of the gastro-intestinal tract (17%). The most common surgical techniques were laparotomy and gastrotomy (50%). The mean duration of hospitalization was 3.8 ± 4 days. The mortality rate was 3%.Conservative treatment of body packers seems to be the best treatment method. Careful monitoring of the patients for possible signs and symptoms of intoxication and gastro-intestinal obstruction is strongly recommended.

  19. Assessing the Epidemiological Data and Management Methods of Body Packers Admitted to a Referral Center in Iran

    PubMed Central

    Alipour-faz, Athena; Shadnia, Shahin; Mirhashemi, Seyyed Hadi; Peyvandi, Maryam; Oroei, Mahbobeh; Shafagh, Omid; Peyvandi, Hassan; Peyvandi, Ali Asghar

    2016-01-01

    Abstract The incidence of smuggling and transporting illegal substances by internal concealment, also known as body packing, is on the rise. The clinical approach to such patients has been changed significantly over the past 2 decades. However, despite a recorded increase in body packing in general, there are controversies in the management of these patients. We aimed to gather data regarding the demographic characteristics, treatment, and outcome of body packers, which were that referred to Loghman Hakim Hospital, Tehran, Iran. The data of all body packers admitted to Loghman Hakim Hospital during 2010 to 2014 were evaluated retrospectively. Data regarding the demographic characteristics of the patients, findings of clinical imaging, treatment, and outcome were recorded. In this study, 175 individuals with a mean age of 31 ± 10 years were assessed. The most common concealed substances were crack (37%), crystal (17%), opium (13%), and heroin (6%). According to the results of surgery and imaging (abdominal radiography or computed tomography), the most common place for concealment was stomach in 33.3% and 12% of cases, respectively. Imaging findings were normal in 18% of the individuals. Forty-eight (27%) patients underwent surgery. The main indications for surgery were clinical manifestations of toxicity (79%) and obstruction of the gastro-intestinal tract (17%). The most common surgical techniques were laparotomy and gastrotomy (50%). The mean duration of hospitalization was 3.8 ± 4 days. The mortality rate was 3%. Conservative treatment of body packers seems to be the best treatment method. Careful monitoring of the patients for possible signs and symptoms of intoxication and gastro-intestinal obstruction is strongly recommended. PMID:27175693

  20. Education in epidemiology: "The Times They Are a-Changin'".

    PubMed

    Samet, Jonathan M; Savitz, David A

    2008-03-01

    "The Changing Face of Epidemiology" is a series of symposia sponsored by Epidemiology for the purpose of addressing topical issues that cut across specialty areas. We comment here on 3 papers presented last summer at a symposium ("Education in Epidemiology: Changing needs for changing times") at the 2007 meeting of the Society for Epidemiologic Research. These papers address current challenges in training epidemiologists, including the rise of molecular epidemiology, the ongoing need to redefine core epidemiologic methods and develop optimum approaches, and the increasing difficulty of assuring competency in primary data collection. We offer suggestions for educational programs and professional organizations on approaching these ongoing challenges.

  1. Cancer Epidemiology Matters Blog

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  2. ADHD in the Arab World: A Review of Epidemiologic Studies

    ERIC Educational Resources Information Center

    Farah, Lynn G.; Fayyad, John A.; Eapen, Valsamma; Cassir,Youmna; Salamoun, Mariana M.; Tabet, Caroline C.; Mneimneh, Zeina N.; Karam, Elie G.

    2009-01-01

    Objective: Epidemiological studies on psychiatric disorders are quite rare in the Arab World. This article reviews epidemiological studies on ADHD in all the Arab countries. Method: All epidemiological studies on ADHD conducted from 1966 through th present were reviewed. Samples were drawn from the general community, primary care clinical…

  3. Quantifying Uncertainty in Epidemiological Models

    SciTech Connect

    Ramanathan, Arvind; Jha, Sumit Kumar

    2012-01-01

    Modern epidemiology has made use of a number of mathematical models, including ordinary differential equation (ODE) based models and agent based models (ABMs) to describe the dynamics of how a disease may spread within a population and enable the rational design of strategies for intervention that effectively contain the spread of the disease. Although such predictions are of fundamental importance in preventing the next global pandemic, there is a significant gap in trusting the outcomes/predictions solely based on such models. Hence, there is a need to develop approaches such that mathematical models can be calibrated against historical data. In addition, there is a need to develop rigorous uncertainty quantification approaches that can provide insights into when a model will fail and characterize the confidence in the (possibly multiple) model outcomes/predictions, when such retrospective analysis cannot be performed. In this paper, we outline an approach to develop uncertainty quantification approaches for epidemiological models using formal methods and model checking. By specifying the outcomes expected from a model in a suitable spatio-temporal logic, we use probabilistic model checking methods to quantify the probability with which the epidemiological model satisfies the specification. We argue that statistical model checking methods can solve the uncertainty quantification problem for complex epidemiological models.

  4. A combinational approach of multilocus sequence typing and other molecular typing methods in unravelling the epidemiology of Erysipelothrix rhusiopathiae strains from poultry and mammals.

    PubMed

    Janßen, Traute; Voss, Matthias; Kühl, Michael; Semmler, Torsten; Philipp, Hans-Christian; Ewers, Christa

    2015-07-21

    Erysipelothrix rhusiopathiae infections re-emerged as a matter of great concern particularly in the poultry industry. In contrast to porcine isolates, molecular epidemiological traits of avian E. rhusiopathiae isolates are less well known. Thus, we aimed to (i) develop a multilocus sequence typing (MLST) scheme for E. rhusiopathiae, (ii) study the congruence of strain grouping based on pulsed-field gel electrophoresis (PFGE) and MLST, (iii) determine the diversity of the dominant immunogenic protein SpaA, and (iv) examine the distribution of genes putatively linked with virulence among field isolates from poultry (120), swine (24) and other hosts (21), including humans (3). Using seven housekeeping genes for MLST analysis we determined 72 sequence types (STs) among 165 isolates. This indicated an overall high diversity, though 34.5% of all isolates belonged to a single predominant ST-complex, STC9, which grouped strains from birds and mammals, including humans, together. PFGE revealed 58 different clusters and congruence with the sequence-based MLST-method was not common. Based on polymorphisms in the N-terminal hyper-variable region of SpaA the isolates were classified into five groups, which followed the phylogenetic background of the strains. More than 90% of the isolates harboured all 16 putative virulence genes tested and only intI, encoding an internalin-like protein, showed infrequent distribution. MLST data determined E. rhusiopathiae as weakly clonal species with limited host specificity. A common evolutionary origin of isolates as well as shared SpaA variants and virulence genotypes obtained from avian and mammalian hosts indicates common reservoirs, pathogenic pathways and immunogenic properties of the pathogen.

  5. [METHODS AND TECHNOLOGIES OF HEALTH RISK ANALYSIS IN THE SYSTEM OF THE STATE MANAGEMENT UNDER ASSURANCE OF THE SANITATION AND EPIDEMIOLOGICAL WELFARE OF POPULATION].

    PubMed

    Zaĭtseva, N V; Popova, A Iu; Maĭ, I V; Shur, P Z

    2015-01-01

    The methodology of the analysis of health risk at the present stage of development of Russian society is in-demand at all levels of government management. In conjunction with the methods of mathematical modeling, spatial-temporal analysis and economic tools the risk assessment in the analysis of the situation makes it possible to determine the level of safety of the population, workers and consumers, to select prior resources, and threat factors as a point for exertion efforts. At the planning stage risk assessment is a basis for the establishment of most effective measures for the minimization of hazard and dangers. At the realization stage the methodology allows to estimate the efficiency of measures; at the control and supervision phase it permits to select out priorities for the concentration of efforts on the objects of maximal health risk for population. Risk assessments, including the elements of evolutionary modeling, are incorporated in the system of state hygienic regulation, the formation of evidence base of harm to health, the organization of control and supervisory activities. This allows you to harmonize the domestic legal framework with ternational legal requirements and ultimately enhances the credibility of the Russian data on the safety of the environment products and services. There is seemed to be actual the further assignment of enforcement of methodology of health risk analysis in the field of assurance of sanitary and epidemiological well-being and health of employers; he development of informational and analytical base in the part of the establishment of models of dependencies "exposure-response" for different types and levels of exposure and risk contingents; the accuracy enhancement of estimations of exposure; improvement of the economic aspects of health risk analysis and forecasting of measures aimed at mitigation of the losses associated with the negative impact of manifold factors on the health of citizens.

  6. Antimicrobial Susceptibility of Flavobacterium psychrophilum from Chilean Salmon Farms and Their Epidemiological Cut-Off Values Using Agar Dilution and Disk Diffusion Methods

    PubMed Central

    Miranda, Claudio D.; Smith, Peter; Rojas, Rodrigo; Contreras-Lynch, Sergio; Vega, J. M. Alonso

    2016-01-01

    Flavobacterium psychrophilum is the most important bacterial pathogen for freshwater farmed salmonids in Chile. The aims of this study were to determine the susceptibility to antimicrobials used in fish farming of Chilean isolates and to calculate their epidemiological cut-off (COWT) values. A number of 125 Chilean isolates of F. psychrophilum were isolated from reared salmonids presenting clinical symptoms indicative of flavobacteriosis and their identities were confirmed by 16S rRNA polymerase chain reaction. Susceptibility to antibacterials was tested on diluted Mueller-Hinton by using an agar dilution MIC method and a disk diffusion method. The COWT values calculated by Normalized Resistance Interpretation (NRI) analysis allow isolates to be categorized either as wild-type fully susceptible (WT) or as manifesting reduced susceptibility (NWT). When MIC data was used, NRI analysis calculated a COWT of ≤0.125, ≤2, and ≤0.5 μg mL-1 for amoxicillin, florfenicol, and oxytetracycline, respectively. For the quinolones, the COWT were ≤1, ≤0.5, and ≤0.125 μg mL-1 for oxolinic acid, flumequine, and enrofloxacin, respectively. The disk diffusion data sets obtained in this work were extremely diverse and were spread over a wide range. For the quinolones there was a close agreement between the frequencies of NWT isolates calculated using MIC and disk data. For oxolinic acid, flumequine, and enrofloxacin the frequencies were 45, 39, and 38% using MIC data, and 42, 41, and 44%, when disk data were used. There was less agreement with the other antimicrobials, because NWT frequencies obtained using MIC and disk data, respectively, were 24 and 10% for amoxicillin, 8 and 2% for florfenicol, and 70 and 64% for oxytetracycline. Considering that the MIC data was more precise than the disk diffusion data, MIC determination would be the preferred method for susceptibility testing for this species and the NWT frequencies derived from the MIC data sets should be considered

  7. Antimicrobial Susceptibility of Flavobacterium psychrophilum from Chilean Salmon Farms and Their Epidemiological Cut-Off Values Using Agar Dilution and Disk Diffusion Methods.

    PubMed

    Miranda, Claudio D; Smith, Peter; Rojas, Rodrigo; Contreras-Lynch, Sergio; Vega, J M Alonso

    2016-01-01

    Flavobacterium psychrophilum is the most important bacterial pathogen for freshwater farmed salmonids in Chile. The aims of this study were to determine the susceptibility to antimicrobials used in fish farming of Chilean isolates and to calculate their epidemiological cut-off (COWT) values. A number of 125 Chilean isolates of F. psychrophilum were isolated from reared salmonids presenting clinical symptoms indicative of flavobacteriosis and their identities were confirmed by 16S rRNA polymerase chain reaction. Susceptibility to antibacterials was tested on diluted Mueller-Hinton by using an agar dilution MIC method and a disk diffusion method. The COWT values calculated by Normalized Resistance Interpretation (NRI) analysis allow isolates to be categorized either as wild-type fully susceptible (WT) or as manifesting reduced susceptibility (NWT). When MIC data was used, NRI analysis calculated a COWT of ≤0.125, ≤2, and ≤0.5 μg mL(-1) for amoxicillin, florfenicol, and oxytetracycline, respectively. For the quinolones, the COWT were ≤1, ≤0.5, and ≤0.125 μg mL(-1) for oxolinic acid, flumequine, and enrofloxacin, respectively. The disk diffusion data sets obtained in this work were extremely diverse and were spread over a wide range. For the quinolones there was a close agreement between the frequencies of NWT isolates calculated using MIC and disk data. For oxolinic acid, flumequine, and enrofloxacin the frequencies were 45, 39, and 38% using MIC data, and 42, 41, and 44%, when disk data were used. There was less agreement with the other antimicrobials, because NWT frequencies obtained using MIC and disk data, respectively, were 24 and 10% for amoxicillin, 8 and 2% for florfenicol, and 70 and 64% for oxytetracycline. Considering that the MIC data was more precise than the disk diffusion data, MIC determination would be the preferred method for susceptibility testing for this species and the NWT frequencies derived from the MIC data sets should be

  8. Epigenetic Epidemiology: Promises for Public Health Research

    PubMed Central

    Bakulski, Kelly M.; Fallin, M. Daniele

    2014-01-01

    Epigenetic changes underlie developmental and age related biology. Promising epidemiologic research implicates epigenetics in disease risk and progression, and suggests epigenetic status depends on environmental risks as well as genetic predisposition. Epigenetics may represent a mechanistic link between environmental exposures, or genetics, and many common diseases, or may simply provide a quantitative biomarker for exposure or disease for areas of epidemiology currently lacking such measures. This great promise is balanced by issues related to study design, measurement tools, statistical methods, and biological interpretation that must be given careful consideration in an epidemiologic setting. This article describes the promises and challenges for epigenetic epidemiology, and suggests directions to advance this emerging area of molecular epidemiology. PMID:24449392

  9. Epidemiology, molecular epidemiology and evolution of bovine respiratory syncytial virus.

    PubMed

    Sarmiento-Silva, Rosa Elena; Nakamura-Lopez, Yuko; Vaughan, Gilberto

    2012-11-30

    The bovine respiratory syncytial virus (BRSV) is an enveloped, negative sense, single-stranded RNA virus belonging to the pneumovirus genus within the family Paramyxoviridae. BRSV has been recognized as a major cause of respiratory disease in young calves since the early 1970s. The analysis of BRSV infection was originally hampered by its characteristic lability and poor growth in vitro. However, the advent of numerous immunological and molecular methods has facilitated the study of BRSV enormously. The knowledge gained from these studies has also provided the opportunity to develop safe, stable, attenuated virus vaccine candidates. Nonetheless, many aspects of the epidemiology, molecular epidemiology and evolution of the virus are still not fully understood. The natural course of infection is rather complex and further complicates diagnosis, treatment and the implementation of preventive measures aimed to control the disease. Therefore, understanding the mechanisms by which BRSV is able to establish infection is needed to prevent viral and disease spread. This review discusses important information regarding the epidemiology and molecular epidemiology of BRSV worldwide, and it highlights the importance of viral evolution in virus transmission.

  10. [Molecular epidemiology in the epidemiological transition].

    PubMed

    Tapia-Conyer, R

    1997-01-01

    The epidemiological transition describes the changes in the health profile of populations where infectious diseases are substituted by chronic or non-communicable diseases. Even in industrialized countries, infectious diseases emerge as important public health problems and with a very important association with several type of neoplasm. Molecular epidemiology brings in new tools for the study of the epidemiological transition by discovering infectious agents as etiology of diseases, neither of both new. Much has been advanced in the understanding of the virulence and resistance mechanism of different strains, or improving the knowledge on transmission dynamics and dissemination pathways of infectious diseases. As to the non-communicable diseases, molecular epidemiology has enhanced the identification of endogenous risk factors link to alterations, molecular changes in genetic material, that will allow a more detail definition of risk and the identification of individual and groups at risk of several diseases. The potential impact of molecular epidemiology in other areas as environmental, lifestyles and nutritional areas are illustrated with several examples.

  11. Multicenter study of epidemiological cutoff values and detection of resistance in Candida spp. to anidulafungin, caspofungin, and micafungin using the Sensititre YeastOne colorimetric method.

    PubMed

    Espinel-Ingroff, A; Alvarez-Fernandez, M; Cantón, E; Carver, P L; Chen, S C-A; Eschenauer, G; Getsinger, D L; Gonzalez, G M; Govender, N P; Grancini, A; Hanson, K E; Kidd, S E; Klinker, K; Kubin, C J; Kus, J V; Lockhart, S R; Meletiadis, J; Morris, A J; Pelaez, T; Quindós, G; Rodriguez-Iglesias, M; Sánchez-Reus, F; Shoham, S; Wengenack, N L; Borrell Solé, N; Echeverria, J; Esperalba, J; Gómez-G de la Pedrosa, E; García García, I; Linares, M J; Marco, F; Merino, P; Pemán, J; Pérez Del Molino, L; Roselló Mayans, E; Rubio Calvo, C; Ruiz Pérez de Pipaon, M; Yagüe, G; Garcia-Effron, G; Guinea, J; Perlin, D S; Sanguinetti, M; Shields, R; Turnidge, J

    2015-11-01

    Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 μg/ml for C. albicans, 0.12, 0.25, and 0.03 μg/ml for C. glabrata complex, 4, 2, and 4 μg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 μg/ml for C. tropicalis, 0.25, 1, and 0.25 μg/ml for C. krusei, 0.25, 1, and 0.12 μg/ml for C. lusitaniae, 4, 2, and 2 μg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 μg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.

  12. Multicenter Study of Epidemiological Cutoff Values and Detection of Resistance in Candida spp. to Anidulafungin, Caspofungin, and Micafungin Using the Sensititre YeastOne Colorimetric Method

    PubMed Central

    Alvarez-Fernandez, M.; Cantón, E.; Carver, P. L.; Chen, S. C.-A.; Eschenauer, G.; Getsinger, D. L.; Gonzalez, G. M.; Grancini, A.; Hanson, K. E.; Kidd, S. E.; Klinker, K.; Kubin, C. J.; Kus, J. V.; Lockhart, S. R.; Meletiadis, J.; Morris, A. J.; Pelaez, T.; Rodriguez-Iglesias, M.; Sánchez-Reus, F.; Shoham, S.; Wengenack, N. L.; Borrell Solé, N.; Echeverria, J.; Esperalba, J.; Gómez-G. de la Pedrosa, E.; García García, I.; Linares, M. J.; Marco, F.; Merino, P.; Pemán, J.; Pérez del Molino, L.; Roselló Mayans, E.; Rubio Calvo, C.; Ruiz Pérez de Pipaon, M.; Yagüe, G.; Garcia-Effron, G.; Perlin, D. S.; Sanguinetti, M.; Shields, R.; Turnidge, J.

    2015-01-01

    Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 μg/ml for C. albicans, 0.12, 0.25, and 0.03 μg/ml for C. glabrata complex, 4, 2, and 4 μg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 μg/ml for C. tropicalis, 0.25, 1, and 0.25 μg/ml for C. krusei, 0.25, 1, and 0.12 μg/ml for C. lusitaniae, 4, 2, and 2 μg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 μg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended. PMID:26282428

  13. Problems of epidemiology in malaria eradication

    PubMed Central

    Yekutiel, P.

    1960-01-01

    With an increasing number of malaria eradication programmes approaching or entering the consolidation phase, the epidemiological features of disappearing malaria are getting better known and defined. At the same time, the old classical methods of measuring malaria prevalence have become inadequate and new methods for the epidemiological assessment of the progress of eradication are being developed. In this article the new methods of assessment and epidemiological and statistical criteria for discontinuing residual spraying and for the stability of consolidation are discussed on the basis of field experience in several countries during the past two or three years. Some prominent epidemiological features of malaria at reduced levels of transmission are described, special attention being given to the role of the asymptomatic carrier in malaria eradication. PMID:13846510

  14. Epidemiology as discourse: the politics of development institutions in the Epidemiological Profile of El Salvador

    PubMed Central

    Aviles, L

    2001-01-01

    STUDY OBJECTIVE—To determine the ways in which institutions devoted to international development influence epidemiological studies.
DESIGN—This article takes a descriptive epidemiological study of El Salvador, Epidemiological Profile, conducted in 1994 by the US Agency for International Development, as a case study. The methods include discourse analysis in order to uncover the ideological basis of the report and its characteristics as a discourse of development.
SETTING—El Salvador.
RESULTS—The Epidemiological Profile theoretical basis, the epidemiological transition theory, embodies the ethnocentrism of a "colonizer's model of the world." This report follows the logic of a discourse of development by depoliticising development, creating abnormalities, and relying on the development consulting industry. The epidemiological transition theory serves as an ideology that legitimises and dissimulates the international order.
CONCLUSIONS—Even descriptive epidemiological assessments or epidemiological profiles are imbued with theoretical assumptions shaped by the institutional setting under which epidemiological investigations are conducted.


Keywords: El Salvador; politics PMID:11160170

  15. The Checkered History of American Psychiatric Epidemiology

    PubMed Central

    Horwitz, Allan V; Grob, Gerald N

    2011-01-01

    Context American psychiatry has been fascinated with statistics ever since the specialty was created in the early nineteenth century. Initially, psychiatrists hoped that statistics would reveal the benefits of institutional care. Nevertheless, their fascination with statistics was far removed from the growing importance of epidemiology generally. The impetus to create an epidemiology of mental disorders came from the emerging social sciences, whose members were concerned with developing a scientific understanding of individual and social behavior and applying it to a series of pressing social problems. Beginning in the 1920s, the interest of psychiatric epidemiologists shifted to the ways that social environments contributed to the development of mental disorders. This emphasis dramatically changed after 1980 when the policy focus of psychiatric epidemiology became the early identification and prevention of mental illness in individuals. Methods This article reviews the major developments in psychiatric epidemiology over the past century and a half. Findings The lack of an adequate classification system for mental illness has precluded the field of psychiatric epidemiology from providing causal understandings that could contribute to more adequate policies to remediate psychiatric disorders. Because of this gap, the policy influence of psychiatric epidemiology has stemmed more from institutional and ideological concerns than from knowledge about the causes of mental disorders. Conclusion Most of the problems that have bedeviled psychiatric epidemiology since its inception remain unresolved. In particular, until epidemiologists develop adequate methods to measure mental illnesses in community populations, the policy contributions of this field will not be fully realized. PMID:22188350

  16. [Epidemiology and public policies].

    PubMed

    Barata, Rita Barradas

    2013-03-01

    The present essay deals with the relation between epidemiology and public policies, highlighting the epidemiology position in the public health field, analyzing the impact of public policies over epidemiological profile and contributions from epidemiology to the lay down, implementation and evaluation of public health policies. In the first title, the essay debates the links between the epidemiology and public health field, the social determinants and political action framework proposed by the WHO's Commission on Social Determinants of Health, and different approaches of health policies. In the second title the essay analyses the reduction of child stunting in Brazil as an example of public policies that impact epidemiological profile. The third title presents three strategic topics for the application of public health policies: reduction of social inequalities in health, health promotion and regulation of products and services that have impact over health. The fourth title discusses the possibilities and difficulties to combine the epidemiological knowledge in the lay down, implementation and evaluation of public policies and, finally, material examples of such relation between epidemiology and public policies are presented.

  17. Vaccine epidemiology: A review

    PubMed Central

    Lahariya, Chandrakant

    2016-01-01

    This review article outlines the key concepts in vaccine epidemiology, such as basic reproductive numbers, force of infection, vaccine efficacy and effectiveness, vaccine failure, herd immunity, herd effect, epidemiological shift, disease modeling, and describes the application of this knowledge both at program levels and in the practice by family physicians, epidemiologists, and pediatricians. A case has been made for increased knowledge and understanding of vaccine epidemiology among key stakeholders including policy makers, immunization program managers, public health experts, pediatricians, family physicians, and other experts/individuals involved in immunization service delivery. It has been argued that knowledge of vaccine epidemiology which is likely to benefit the society through contributions to the informed decision-making and improving vaccination coverage in the low and middle income countries (LMICs). The article ends with suggestions for the provision of systematic training and learning platforms in vaccine epidemiology to save millions of preventable deaths and improve health outcomes through life-course. PMID:27453836

  18. Comparison of Three Statistical Methods for Establishing Tentative Wild-Type Population and Epidemiological Cutoff Values for Echinocandins, Amphotericin B, Flucytosine, and Six Candida Species as Determined by the Colorimetric Sensititre YeastOne Method

    PubMed Central

    Pemán, Javier; Hervás, David; Iñiguez, Carmen; Navarro, David; Echeverría, Julia; Martínez-Alarcón, José; Fontanals, Dionisia; Gomila-Sard, Bárbara; Buendía, Buenaventura; Torroba, Luis; Ayats, Josefina; Bratos, Angel; Sánchez-Reus, Ferran; Fernández-Natal, Isabel

    2012-01-01

    The Sensititre YeastOne (SYO) method is a widely used method to determine the susceptibility of Candida spp. to antifungal agents. CLSI clinical breakpoints (CBP) have been reported for antifungals, but not using this method. In the absence of CBP, epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (those without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of any susceptibility test. The ECVs for five agents, obtained using the MIC distributions determined by the SYO test, were calculated and contrasted with those for three statistical methods and the MIC50 and modal MIC, both plus 2-fold dilutions. The median ECVs (in mg/liter) (% of isolates inhibited by MICs equal to or less than the ECV; number of isolates tested) of the five methods for anidulafungin, micafungin, caspofungin, amphotericin B, and flucytosine, respectively, were as follows: 0.25 (98.5%; 656), 0.06 (95.1%; 659), 0.25 (98.7%; 747), 2 (100%; 923), and 1 (98.5%; 915) for Candida albicans; 8 (100%; 352), 4 (99.2%; 392), 2 (99.2%; 480), 1 (99.8%; 603), and 0.5 (97.9%; 635) for C. parapsilosis; 1 (99.2%; 123), 0.12 (99.2%; 121), 0.25 (99.2%; 138), 2 (100%; 171), and 0.5 (97.2%; 175) for C. tropicalis; 0.12 (96.6%; 174), 0.06 (96%; 176), 0.25 (98.4%; 188), 2 (100%; 209), and 0.25 (97.6%; 208) for C. glabrata; 0.25 (97%; 33), 0.5 (93.9%; 33), 1 (91.9%; 37), 4 (100%; 51), and 32 (100%; 53) for C. krusei; and 4 (100%; 33), 2 (100%; 33), 2 (100%; 54), 1 (100%; 90), and 0.25 (93.4%; 91) for C. orthopsilosis. The three statistical methods gave similar ECVs (within one dilution) and included ≥95% of isolates. These tentative ECVs would be useful for monitoring the emergence of isolates with reduced susceptibility by use of the SYO method. PMID:23015676

  19. Arteriovenous malformations: epidemiology and clinical presentation.

    PubMed

    Laakso, Aki; Hernesniemi, Juha

    2012-01-01

    Arteriovenous malformations (AVMs) of the brain are relatively rare congenital developmental vascular lesions. They may cause hemorrhagic stroke, epilepsy, chronic headache, or focal neurologic deficits, and the incidence of asymptomatic AVMs is increasing due to widespread availability of noninvasive imaging methods. Since the most severe complication of an AVM is hemorrhagic stroke, most epidemiologic studies have concentrated on the hemorrhage risk and its risk factors. In this article, the authors discuss the epidemiology, presenting symptoms, and hemorrhage risk associated with brain AVMs.

  20. Criticality in epidemiology

    NASA Astrophysics Data System (ADS)

    Stollenwerk, Nico; Jansen, Vincent A. A.

    For a long time criticality has been considered in epidemiological models. We review the body of theory developed over the last twenty five years for the simplest models. It is at first glance difficult to imagine that an epidemiological system operates at a very fine tuned critical state as opposed to any other parameter region. However, the advent of self-organized criticality has given hints in how to interpret large fluctuations observed in many natural systems including epidemiological systems. We show some scenarios where criticality has been observed (e.g., measles under vaccination) and where evolution towards a critical state can explain fluctuations (e.g., meningococcal disease.)

  1. "Epidemiological criminology": coming full circle.

    PubMed

    Akers, Timothy A; Lanier, Mark M

    2009-03-01

    Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose "epidemiological criminology" as a bridging framework.

  2. Epidemiology of Enterocytozoon bieneusi Infection in Humans

    PubMed Central

    Matos, Olga; Lobo, Maria Luisa; Xiao, Lihua

    2012-01-01

    A review was conducted to examine published works that focus on the complex epidemiology of Enterocytozoon bieneusi infection in humans. Studies on the prevalence of these emerging microsporidian pathogens in humans, in developed and developing countries, the different clinical spectra of E. bieneusi intestinal infection in children, in different settings, and the risk factors associated with E. bieneusi infection have been reviewed. This paper also analyses the impact of the recent application of PCR-based molecular methods for species-specific identification and genotype differentiation has had in increasing the knowledge of the molecular epidemiology of E. bieneusi in humans. The advances in the epidemiology of E. bieneusi, in the last two decades, emphasize the importance of epidemiological control and prevention of E. bieneusi infections, from both the veterinary and human medical perspectives. PMID:23091702

  3. Epidemiology of Lice

    ERIC Educational Resources Information Center

    Juranek, Dennis D.

    1977-01-01

    Research into the epidemiology of lice indicates that infestation is uncommon in blacks, more common in females than males, significantly higher in low income groups, and transmission is by way of articles of clothing. (JD)

  4. Epidemiology & Genomics Research Program

    Cancer.gov

    The Epidemiology and Genomics Research Program, in the National Cancer Institute's Division of Cancer Control and Population Sciences, funds research in human populations to understand the determinants of cancer occurrence and outcomes.

  5. EPIDEMIOLOGY AND EXPOSURE ASSESSMENT

    EPA Science Inventory

    Research collaborations between the National Health and Environmental Effects Research Laboratory (NHEERL) and the National Exposure Research Laboratory (NERL) centered on the development and application of exposure analysis tools in environmental epidemiology include the El Paso...

  6. Cancer Epidemiology Cohorts

    Cancer.gov

    Cohort studies are fundamental for epidemiological research by helping researchers better understand the etiology of cancer and provide insights into the key determinants of this disease and its outcomes.

  7. Molecular Epidemiology of Tuberculosis: Current Insights

    PubMed Central

    Mathema, Barun; Kurepina, Natalia E.; Bifani, Pablo J.; Kreiswirth, Barry N.

    2006-01-01

    Molecular epidemiologic studies of tuberculosis (TB) have focused largely on utilizing molecular techniques to address short- and long-term epidemiologic questions, such as in outbreak investigations and in assessing the global dissemination of strains, respectively. This is done primarily by examining the extent of genetic diversity of clinical strains of Mycobacterium tuberculosis. When molecular methods are used in conjunction with classical epidemiology, their utility for TB control has been realized. For instance, molecular epidemiologic studies have added much-needed accuracy and precision in describing transmission dynamics, and they have facilitated investigation of previously unresolved issues, such as estimates of recent-versus-reactive disease and the extent of exogenous reinfection. In addition, there is mounting evidence to suggest that specific strains of M. tuberculosis belonging to discrete phylogenetic clusters (lineages) may differ in virulence, pathogenesis, and epidemiologic characteristics, all of which may significantly impact TB control and vaccine development strategies. Here, we review the current methods, concepts, and applications of molecular approaches used to better understand the epidemiology of TB. PMID:17041139

  8. Multicenter Study of Method-Dependent Epidemiological Cutoff Values for Detection of Resistance in Candida spp. and Aspergillus spp. to Amphotericin B and Echinocandins for the Etest Agar Diffusion Method.

    PubMed

    Espinel-Ingroff, A; Arendrup, M; Cantón, E; Cordoba, S; Dannaoui, E; García-Rodríguez, J; Gonzalez, G M; Govender, N P; Martin-Mazuelos, E; Lackner, M; Lass-Flörl, C; Linares Sicilia, M J; Rodriguez-Iglesias, M A; Pelaez, T; Shields, R K; Garcia-Effron, G; Guinea, J; Sanguinetti, M; Turnidge, J

    2017-01-01

    Method-dependent Etest epidemiological cutoff values (ECVs) are not available for susceptibility testing of either Candida or Aspergillus species with amphotericin B or echinocandins. In addition, reference caspofungin MICs for Candida spp. are unreliable. Candida and Aspergillus species wild-type (WT) Etest MIC distributions (microorganisms in a species-drug combination with no detectable phenotypic resistance) were established for 4,341 Candida albicans, 113 C. dubliniensis, 1,683 C. glabrata species complex (SC), 709 C. krusei, 767 C. parapsilosis SC, 796 C. tropicalis, 1,637 Aspergillus fumigatus SC, 238 A. flavus SC, 321 A. niger SC, and 247 A. terreus SC isolates. Etest MICs from 15 laboratories (in Argentina, Europe, Mexico, South Africa, and the United States) were pooled to establish Etest ECVs. Anidulafungin, caspofungin, micafungin, and amphotericin B ECVs (in micrograms per milliliter) encompassing ≥97.5% of the statistically modeled population were 0.016, 0.5, 0.03, and 1 for C. albicans; 0.03, 1, 0.03, and 2 for C. glabrata SC; 0.06, 1, 0.25, and 4 for C. krusei; 8, 4, 2, and 2 for C. parapsilosis SC; and 0.03, 1, 0.12, and 2 for C. tropicalis The amphotericin B ECV was 0.25 μg/ml for C. dubliniensis and 2, 8, 2, and 16 μg/ml for the complexes of A. fumigatus, A. flavus, A. niger, and A. terreus, respectively. While anidulafungin Etest ECVs classified 92% of the Candida fks mutants evaluated as non-WT, the performance was lower for caspofungin (75%) and micafungin (84%) cutoffs. Finally, although anidulafungin (as an echinocandin surrogate susceptibility marker) and amphotericin B ECVs should identify Candida and Aspergillus isolates with reduced susceptibility to these agents using the Etest, these ECVs will not categorize a fungal isolate as susceptible or resistant, as breakpoints do.

  9. Epidemiology of Lung Cancer

    PubMed Central

    Brock, Malcolm V.; Ford, Jean G.; Samet, Jonathan M.; Spivack, Simon D.

    2013-01-01

    Background: Ever since a lung cancer epidemic emerged in the mid-1900s, the epidemiology of lung cancer has been intensively investigated to characterize its causes and patterns of occurrence. This report summarizes the key findings of this research. Methods: A detailed literature search provided the basis for a narrative review, identifying and summarizing key reports on population patterns and factors that affect lung cancer risk. Results: Established environmental risk factors for lung cancer include smoking cigarettes and other tobacco products and exposure to secondhand tobacco smoke, occupational lung carcinogens, radiation, and indoor and outdoor air pollution. Cigarette smoking is the predominant cause of lung cancer and the leading worldwide cause of cancer death. Smoking prevalence in developing nations has increased, starting new lung cancer epidemics in these nations. A positive family history and acquired lung disease are examples of host factors that are clinically useful risk indicators. Risk prediction models based on lung cancer risk factors have been developed, but further refinement is needed to provide clinically useful risk stratification. Promising biomarkers of lung cancer risk and early detection have been identified, but none are ready for broad clinical application. Conclusions: Almost all lung cancer deaths are caused by cigarette smoking, underscoring the need for ongoing efforts at tobacco control throughout the world. Further research is needed into the reasons underlying lung cancer disparities, the causes of lung cancer in never smokers, the potential role of HIV in lung carcinogenesis, and the development of biomarkers. PMID:23649439

  10. Causal diagrams in systems epidemiology

    PubMed Central

    2012-01-01

    Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback. PMID:22429606

  11. Legionellaceae in the hospital water-supply. Epidemiological link with disease and evaluation of a method for control of nosocomial legionnaires' disease and Pittsburgh pneumonia.

    PubMed

    Best, M; Yu, V L; Stout, J; Goetz, A; Muder, R R; Taylor, F

    1983-08-06

    An epidemiological link was found between contamination of a hospital water-supply by Legionella pneumophila and by Pittsburgh pneumonia agent (PPA) and subsequent cases of nosocomial legionnaires' disease and Pittsburgh pneumonia. The extent of L pneumophila isolation from the water-supply paralleled the occurrence of disease. Whenever L pneumophila was isolated from more than 30% of ten selected water sites, nosocomial legionellosis occurred. The temperature of the hot water tanks was raised to 60-77 degrees C for 72 h, and water outlets were flushed for 30 min with hot water. A decline in numbers of L pneumophila and PPA in the water-supply was followed by a fall in the incidence of legionnaires' disease and Pittsburgh pneumonia. In addition, intermittent raising of the temperature in the hot water system decreased both the number of months in which disease occurred and the proportion of nosocomial pneumonias caused by these organisms.

  12. Epidemiology 101: toward an educated citizenry.

    PubMed

    Marantz, Paul R

    2008-09-01

    Epidemiology, as the core science underpinning public health, encompasses methods and concepts that are fundamental to understanding health-related information and health policy. Thus, understanding these concepts would enhance the lay public's ability to make informed decisions with respect to health and prevention, and teaching epidemiology at the undergraduate level would be consistent with the goal of creating an educated citizenry. While epidemiology has traditionally been taught largely within graduate schools, there has been experience at the undergraduate level as well. This experience has demonstrated that such courses are popular and effective. While there may be some challenges inherent to teaching Epidemiology 101 at every college and university, this is a worthy and important goal, and most challenges can be successfully overcome with creativity and effort. Perhaps the greatest barrier is instinctive resistance to this idea, since most faculty with epidemiology training received such training in graduate schools. It is up to us to cast off those preconceptions; if one explores the notion of undergraduate epidemiology teaching with an open and unbiased mind, the logic, feasibility, and importance of this effort becomes clear.

  13. [Causal analysis approaches in epidemiology].

    PubMed

    Dumas, O; Siroux, V; Le Moual, N; Varraso, R

    2014-02-01

    Epidemiological research is mostly based on observational studies. Whether such studies can provide evidence of causation remains discussed. Several causal analysis methods have been developed in epidemiology. This paper aims at presenting an overview of these methods: graphical models, path analysis and its extensions, and models based on the counterfactual approach, with a special emphasis on marginal structural models. Graphical approaches have been developed to allow synthetic representations of supposed causal relationships in a given problem. They serve as qualitative support in the study of causal relationships. The sufficient-component cause model has been developed to deal with the issue of multicausality raised by the emergence of chronic multifactorial diseases. Directed acyclic graphs are mostly used as a visual tool to identify possible confounding sources in a study. Structural equations models, the main extension of path analysis, combine a system of equations and a path diagram, representing a set of possible causal relationships. They allow quantifying direct and indirect effects in a general model in which several relationships can be tested simultaneously. Dynamic path analysis further takes into account the role of time. The counterfactual approach defines causality by comparing the observed event and the counterfactual event (the event that would have been observed if, contrary to the fact, the subject had received a different exposure than the one he actually received). This theoretical approach has shown limits of traditional methods to address some causality questions. In particular, in longitudinal studies, when there is time-varying confounding, classical methods (regressions) may be biased. Marginal structural models have been developed to address this issue. In conclusion, "causal models", though they were developed partly independently, are based on equivalent logical foundations. A crucial step in the application of these models is the

  14. The epidemiology of male infertility.

    PubMed

    Winters, Brian R; Walsh, Thomas J

    2014-02-01

    The purpose of this review is to integrate understanding of epidemiology and infertility. A primer on epidemiologic science and an example disease for which the design of epidemiologic investigations is readily apparent are provided. Key features of infertility that limit epidemiologic investigation are described and a survey of available data on the epidemiology of infertility provided. Finally, the work that must be completed to move this area of research forward is proposed, and, with this new perspective of "infertility as a disease," improvements envisioned in public health that may be gained through improved understanding of the epidemiology of male infertility.

  15. [The background, development and perspectives of modern epidemiology].

    PubMed

    Méndez, Fabián

    2013-01-01

    Epidemiology is an ongoing discipline (i.e. still being constructed) and many of the foundations of the theory and methods now in use were mostly developed during the second half of the twentieth century, arising from what is known today as "modern epidemiology". This paper summary the history and main ideas which guided epidemiology at that time, the debates and divisions that characterized such advance and presents a "biased" point of view concerning the perspectives which could help thinking about the disciplinary development of epidemiology.

  16. Multicenter Study of Isavuconazole MIC Distributions and Epidemiological Cutoff Values for Aspergillus spp. for the CLSI M38-A2 Broth Microdilution Method

    PubMed Central

    Chowdhary, A.; Gonzalez, G. M.; Lass-Flörl, C.; Martin-Mazuelos, E.; Meis, J.; Peláez, T.; Pfaller, M. A.; Turnidge, J.

    2013-01-01

    Epidemiological cutoff values (ECVs) were established for the new triazole isavuconazole and Aspergillus species wild-type (WT) MIC distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) that were defined with 855 Aspergillus fumigatus, 444 A. flavus, 106 A. nidulans, 207 A. niger, 384 A. terreus, and 75 A. versicolor species complex isolates; 22 Aspergillus section Usti isolates were also included. CLSI broth microdilution MIC data gathered in Europe, India, Mexico, and the United States were aggregated to statistically define ECVs. ECVs were 1 μg/ml for the A. fumigatus species complex, 1 μg/ml for the A. flavus species complex, 0.25 μg/ml for the A. nidulans species complex, 4 μg/ml for the A. niger species complex, 1 μg/ml for the A. terreus species complex, and 1 μg/ml for the A. versicolor species complex; due to the small number of isolates, an ECV was not proposed for Aspergillus section Usti. These ECVs may aid in detecting non-WT isolates with reduced susceptibility to isavuconazole due to cyp51A (an A. fumigatus species complex resistance mechanism among the triazoles) or other mutations. PMID:23716059

  17. Web tools for molecular epidemiology of tuberculosis.

    PubMed

    Shabbeer, Amina; Ozcaglar, Cagri; Yener, Bülent; Bennett, Kristin P

    2012-06-01

    In this study we explore publicly available web tools designed to use molecular epidemiological data to extract information that can be employed for the effective tracking and control of tuberculosis (TB). The application of molecular methods for the epidemiology of TB complement traditional approaches used in public health. DNA fingerprinting methods are now routinely employed in TB surveillance programs and are primarily used to detect recent transmissions and in outbreak investigations. Here we present web tools that facilitate systematic analysis of Mycobacterium tuberculosis complex (MTBC) genotype information and provide a view of the genetic diversity in the MTBC population. These tools help answer questions about the characteristics of MTBC strains, such as their pathogenicity, virulence, immunogenicity, transmissibility, drug-resistance profiles and host-pathogen associativity. They provide an integrated platform for researchers to use molecular epidemiological data to address current challenges in the understanding of TB dynamics and the characteristics of MTBC.

  18. Phylogenetically resolving epidemiologic linkage

    PubMed Central

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-01-01

    Although the use of phylogenetic trees in epidemiological investigations has become commonplace, their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the true transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. We confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results. PMID:26903617

  19. Epidemiology of Down Syndrome

    ERIC Educational Resources Information Center

    Sherman, Stephanie L.; Allen, Emily G.; Bean, Lora H.; Freeman, Sallie B.

    2007-01-01

    Down syndrome (DS) is the most commonly identified genetic form of mental retardation and the leading cause of specific birth defects and medical conditions. Traditional epidemiological studies to determine the prevalence, cause, and clinical significance of the syndrome have been conducted over the last 100 years. DS has been estimated to occur…

  20. Epidemiology of Cardiovascular Diseases.

    ERIC Educational Resources Information Center

    Jenkins, C. David

    1988-01-01

    Reviews epidemiological studies of cardiovascular diseases especially coronary heart disease (CHD), to document their major public health importance, changes in mortality during this century, and international comparisons of trends. Finds major risk factors for CHD are determined in large part by psychosocial and behavioral mechanisms. Asserts…

  1. Phylogenetically resolving epidemiologic linkage

    SciTech Connect

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-02-22

    The use of phylogenetic trees in epidemiological investigations has become commonplace, but their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the true transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. Moreover, we confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results.

  2. Phylogenetically resolving epidemiologic linkage

    DOE PAGES

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-02-22

    The use of phylogenetic trees in epidemiological investigations has become commonplace, but their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the truemore » transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. Moreover, we confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results.« less

  3. [Analytical epidemiology of urolithiasis].

    PubMed

    Kodama, H; Ohno, Y

    1989-06-01

    In this paper, urolithiasis is reviewed from the standpoint of analytical epidemiology, which examines a statistical association between a given disease and a hypothesized factor with an aim of inferring its causality. Factors incriminated epidemiologically for stone formation include age, sex, occupation, social class (level of affluence), season of the year and climate, dietary and fluid intake and genetic prodisposition. Since some of these factors are interlinked, they are broadly classified into five categories and epidemiologically looked over here. Genetic predisposition is essentially endorsed by the more frequent episodes of stone formation in the family members of stone formers, as compared to non-stone formers. Nevertheless, some environmental factors (likely to be dietary habits) shared by family members are believed to be relatively more important than genetic predisposition. A hot, sunny climate may influence stone formation through inducing dehydration with increased perspiration and increased solute concentration with decreased urine volume, coupled with inadequate liquid intake, and possibly through the greater exposure to ultraviolet radiation which eventually results in an increased vitamin D production, conceivably correlated with seasonal variation in calcium and oxalate excretion to the urine. Urinary tract infections are importantly involved in the formation of magnesium ammonium phosphate stones in particular. The association with regional water hardness is still in controversy. Excessive intake of coffee, tea and alcoholic beverages seemingly increase the risk of renal calculi, though not consistently confirmed. Many dietary elements have been suggested by numerous clinical and experimental investigations, but a few elements are substantiated by analytical epidemiological investigations. An increased ingestion of animal protein and sugar and a decreased ingestion of dietary fiber and green-yellow vegetables are linked with the higher

  4. Causation in epidemiology

    PubMed Central

    Parascandola, M; Weed, D

    2001-01-01

    Causation is an essential concept in epidemiology, yet there is no single, clearly articulated definition for the discipline. From a systematic review of the literature, five categories can be delineated: production, necessary and sufficient, sufficient-component, counterfactual, and probabilistic. Strengths and weaknesses of these categories are examined in terms of proposed characteristics of a useful scientific definition of causation: it must be specific enough to distinguish causation from mere correlation, but not so narrow as to eliminate apparent causal phenomena from consideration. Two categories—production and counterfactual—are present in any definition of causation but are not themselves sufficient as definitions. The necessary and sufficient cause definition assumes that all causes are deterministic. The sufficient-component cause definition attempts to explain probabilistic phenomena via unknown component causes. Thus, on both of these views, heavy smoking can be cited as a cause of lung cancer only when the existence of unknown deterministic variables is assumed. The probabilistic definition, however, avoids these assumptions and appears to best fit the characteristics of a useful definition of causation. It is also concluded that the probabilistic definition is consistent with scientific and public health goals of epidemiology. In debates in the literature over these goals, proponents of epidemiology as pure science tend to favour a narrower deterministic notion of causation models while proponents of epidemiology as public health tend to favour a probabilistic view. The authors argue that a single definition of causation for the discipline should be and is consistent with both of these aims. It is concluded that a counterfactually-based probabilistic definition is more amenable to the quantitative tools of epidemiology, is consistent with both deterministic and probabilistic phenomena, and serves equally well for the acquisition and the

  5. Heart Failure Epidemiology: European Perspective

    PubMed Central

    Guha, K; McDonagh, T

    2013-01-01

    Heart failure poses an increasing problem for global healthcare systems. The epidemiological data which has been accrued over the last thirty years has predominantly been accumulated from experience within North America and Europe. Initial large cohort, prospective longitudinal studies produced the first publications; however latterly the focus has shifted onto epidemiological data governing hospitalisation and mortality. The emphasis behind this shift has been the resource implications with regards to repetitive, costly and prolonged hospitalisation. The European experience in heart failure, though similar to North America has recently demonstrated differences in hospitalisation which may underlie the differences between healthcare system configuration. Heart failure however remains an increasing global problem and the endpoint of a variety of cardiovascular diseases. Allied with the fact of increasingly elderly populations and prior data demonstrating a steep rise in prevalent cases within more elderly populations, it is likely that the increasing burden of disease will continue to pose challenges for modern healthcare. Despite the predicted increase in the number of patients affected by heart failure, over the last thirty years, a clear management algorithm has evolved for the use of pharmacotherapies (neuro-hormonal antagonists), device based therapies (Implantable Cardioverting Defibrillator (ICD) and Cardiac Resynchronisation Therapy (CRT)) and mechanical therapies including left ventricular assist devices and cardiac transplantation. Though the management of such patients has been clearly delineated in national and international guidelines, the underuse of all available and appropriate therapies remains a significant problem. When comparing various epidemiological studies from different settings and timepoints, it should be remembered that rates of prevalence and incidence may vary depending upon the definition used, methods of accumulating information (with

  6. Recent Epidemiological Trends of Stroke

    PubMed Central

    Park, Hyun-Seok; Kang, Myong-Jin

    2008-01-01

    Objective Rapid increase in aged population and westernization of lifestyle have modified epidemiological status of stroke. The purpose of this study is to analyze changing trends of stroke epidemiology in South Korea. Methods We reviewed retrospectively medical records of 1,124 cases diagnosed as stroke among 54,534 patients who visited the Emergency Medical Center at our hospital from January 1994 to December 1996 (Group A). Also, we evaluated 1,705 cases diagnosed as stroke among 55,381 patients who visited to the same hospital from January 2003 to December 2005 (Group B). The variable features of stroke, such as age, sex, seasonal variation and distribution of stroke subtypes were studied by comparing group A with B. Results In group A, hemorrhagic stroke (67.9%) was more prevalent than ischemic stroke (32.1%). However, group B showed that the ratio of hemorrhagic stroke (40.3%) to ischemic stroke (59.6%) has been reversed. The highest incidence of stroke was noted in their sixties and seventies of age in group B, which was older than that of group A. In group A, male ischemic stroke (IS) patients outnumbered female patients (1.26:1). Moreover, this gender disproportion became higher in group B (1.53:1). In group A, the number of male intracerebral hermorrhage (ICH) patients were similar to that of female patients (0.97:1). However, male ICH patients outnumbered female patients in group B (1.23:1). As for subarachnoid hemorrhage (SAH), female patients outnumbered male patients more than two-fold in both groups. Both groups showed that the occurrence of ischemic stroke was highest in summer, but that of hemorrhagic stroke was the highest in winter. Conclusion This study showed the changing trends of stroke in its distribution of subtypes. Multicenter prospective study using stroke registry would be required for the determination of national epidemiologic trends. PMID:19096539

  7. An argument for a consequentialist epidemiology.

    PubMed

    Galea, Sandro

    2013-10-15

    Epidemiology is the study of the causes and distributions of diseases in human populations so that we may identify ways to prevent and control disease. Although this definition broadly serves us well, I suggest that in recent decades, our discipline's robust interest in identifying causes has come at the expense of a more rigorous engagement with the second part of our vision for ourselves-the intent for us to intervene-and that this approach threatens to diminish our field's relevance. I argue here for a consequentialist epidemiology, a formalization and recalibration of the philosophical foundations of our discipline. I discuss how epidemiology is, at its core, more comfortably a consequentialist, as opposed to a deontological, discipline. A more consequentialist approach to epidemiology has several implications. It clarifies our research priorities, offers a perspective on the place of novel epidemiologic approaches and a metric to evaluate the utility of new methods, elevates the importance of global health and considerations about equity to the discipline, brings into sharp focus our engagement in implementation and translational science, and has implications for how we teach our students. I intend this article to be a provocation that can help clarify our disciplinary intentions.

  8. [Hardy-Weinberg equilibrium in genetic epidemiology].

    PubMed

    Liu, Hong; Hu, Yonghua

    2010-01-01

    Hardy-Weinberg equilibrium test is the base of genetic epidemiology. The new methods for Hardy-Weinberg equilibrium test involve: X chromosome-linked single nucleotide polymorphism Hardy-Weinberg test, inbreeding coefficient (F) test, an incomplete enumeration algorithm for an exact test of Hardy-Weinberg proportions with multiple alleles, and graphical tests for Hardy-Weinberg equilibrium based on the ternary plot. It is necessary to conduct Hardy-Weinberg equilibrium test in genetic epidemiology studies and adjust the associations as deviation of Hardy-Weinberg equilibrium occurs.

  9. Child and Adolescent Psychiatric Epidemiology in India

    PubMed Central

    Bhola, Poornima; Kapur, Malavika

    2003-01-01

    The increasing focus on child mental health in developing countries like India points to the importance of epidemiological data in developing training, service and research paradigms.This review attempts to synthesise and evaluate the available research on the prevalence of child and adolescent psychiatric disorders in India and highlight significant conceptual and methodological trends. It identified 55 epidemiological studies conducted between 1964 and 2002 in the community and school settings. Despite considerable progress, various methodological lacunae continue to limit the value of the epidemiological surveys. These include issues related to sampling, case definition methods, tools, multi-informant data and data analysis. The importance of a socio-culturally relevant research framework has been highlighted. The review suggests directions for future research to guide planning of services that meet the mental health needs of vulnerable children and adolescents PMID:21206860

  10. Association Between Cannabis and Psychosis: Epidemiologic Evidence.

    PubMed

    Gage, Suzanne H; Hickman, Matthew; Zammit, Stanley

    2016-04-01

    Associations between cannabis use and psychotic outcomes are consistently reported, but establishing causality from observational designs can be problematic. We review the evidence from longitudinal studies that have examined this relationship and discuss the epidemiologic evidence for and against interpreting the findings as causal. We also review the evidence identifying groups at particularly high risk of developing psychosis from using cannabis. Overall, evidence from epidemiologic studies provides strong enough evidence to warrant a public health message that cannabis use can increase the risk of psychotic disorders. However, further studies are required to determine the magnitude of this effect, to determine the effect of different strains of cannabis on risk, and to identify high-risk groups particularly susceptible to the effects of cannabis on psychosis. We also discuss complementary epidemiologic methods that can help address these questions.

  11. GIS ANALYSIS FOR EPIDEMIOLOGIC RECREATIONAL WATER SUTDIES

    EPA Science Inventory

    Introduction: The Beaches Act of 2000 requires that the Agency develop new rapid method water quality indicators (2 hours or less) that predict whether or not coastal water is safe for swimming. This new set of water quality indicators must be validated through the epidemiologi...

  12. The Epidemiology of Peace and War.

    ERIC Educational Resources Information Center

    Beer, Francis A.

    Health science (epidemiology) is a relatively advanced discipline which offers theories and methods which could be useful in peace science (polemology). Similarities between war and disease, peace and health, center around concern with prevention of physical damage and death on the one hand and preservation and extension of human life on the…

  13. Molecular Epidemiology of Foodborne Pathogens

    NASA Astrophysics Data System (ADS)

    Chen, Yi; Brown, Eric; Knabel, Stephen J.

    The purpose of this chapter is to describe the basic principles and advancements in the molecular epidemiology of foodborne pathogens. Epidemiology is the study of the distribution and determinants of infectious diseases and/or the dynamics of disease transmission. The goals of epidemiology include the identification of physical sources, routes of transmission of infectious agents, and distribution and relationships of different subgroups. Molecular epidemiology is the study of epidemiology at the molecular level. It has been defined as "a science that focuses on the contribution of potential genetic and environmental risk factors, identified at the molecular level, to the etiology, distribution and prevention of diseases within families and across populations".

  14. Advances in spatial epidemiology and geographic information systems.

    PubMed

    Kirby, Russell S; Delmelle, Eric; Eberth, Jan M

    2017-01-01

    The field of spatial epidemiology has evolved rapidly in the past 2 decades. This study serves as a brief introduction to spatial epidemiology and the use of geographic information systems in applied research in epidemiology. We highlight technical developments and highlight opportunities to apply spatial analytic methods in epidemiologic research, focusing on methodologies involving geocoding, distance estimation, residential mobility, record linkage and data integration, spatial and spatio-temporal clustering, small area estimation, and Bayesian applications to disease mapping. The articles included in this issue incorporate many of these methods into their study designs and analytical frameworks. It is our hope that these studies will spur further development and utilization of spatial analysis and geographic information systems in epidemiologic research.

  15. Epidemiology and moral philosophy.

    PubMed Central

    Westrin, C G; Nilstun, T; Smedby, B; Haglund, B

    1992-01-01

    To an increasing extent ethical controversies affect and sometimes obstruct public health work and epidemiological research. In order to improve communication between the concerned parties a model for identification and analysis of ethical conflicts in individual-based research has been worked out in co-operation between epidemiologists and moral philosophers. The model has two dimensions. One dimension specifies relevant ethical principles (as beneficence, non-maleficence, autonomy and justice). The other dimension specifies the groups of persons involved in the conflict under consideration (for example: the study-population, individuals who may benefit from the results, the researchers and their personnel, the community at large). The model has been applied to the problem of legitimacy of case-register research and to problems in psychiatric health services research as well as epidemiological research. PMID:1460647

  16. [Epidemiological situation of Chad].

    PubMed

    Korzeniewski, Krzysztof

    2008-10-01

    Chad, the land located in Central Africa nowadays is one of the poorest countries in the world, what is connected with catastrophic demographic indicators and numerous cases of infectious diseases among local population as well as external and internal refugees. Epidemiologic profile is dominated by vector-, water-, food-borne, respiratory, and sexually transmitted diseases. Environmental factors, such as an effect of high temperature, sand and dust storms also pose essential threat. This is related to location of majority of Chad territory in the area of Sahara and Sahel. The article presents information concerning current epidemiological hazards encountered by visitors in this country. This knowledge is essential for Polish health service and armed forces in the context of forming of EUFOR mission in Chad with participation of our soldiers.

  17. Epidemiology of colorectal cancer

    PubMed Central

    Marley, Andrew R; Nan, Hongmei

    2016-01-01

    Colorectal cancer is currently the third deadliest cancer in the United States and will claim an estimated 49,190 U.S. lives in 2016. The purpose of this review is to summarize our current understanding of this disease, based on nationally published statistics and information presented in peer-reviewed journal articles. Specifically, this review will cover the following topics: descriptive epidemiology (including time and disease trends both in the United States and abroad), risk factors (environmental, genetic, and gene-environment interactions), screening, prevention and control, and treatment. Landmark discoveries in colorectal cancer risk factor research will also be presented. Based on the information reviewed for this report, we suggest that future U.S. public health efforts aim to increase colorectal cancer screening among African American communities, and that future worldwide colorectal cancer epidemiology studies should focus on researching nutrient-gene interactions towards the goal of improving personalized treatment and prevention strategies. PMID:27766137

  18. The leukemias: Epidemiologic aspects

    SciTech Connect

    Linet, M.S.

    1984-01-01

    Particularly geared to physicians and cancer researchers, this study of the epidemiology and etiology of leukemia analyzes the four major leukemia subtypes in terms of genetic and familial determinant factors and examines the incidence, distribution and frequency of reported leukemia clusters. Linet discusses the connection between other types of malignancies, their treatments, and the subsequent development of leukemia and evaluates the impact on leukemia onset of such environmental factors as radiation therapy, drugs, and occupational hazards.

  19. Epidemiology of venous thromboembolism.

    PubMed Central

    Coon, W W

    1977-01-01

    This review of the epidemiology of venous thromboembolism includes estimates of incidence and prevalence of venous thrombosis and its sequelae, a discussion geographical, annual and seasonal variations and data concerning possible risk factors. Selection of patients at increased risk for development of deep venous thrombosis or pulmonary embolism for specific diagnostic screening or for prophylactic therapy with low-dose heparin may be a more effective approach to lowering morbidity and mortality from this disease. PMID:329779

  20. Understanding tuberculosis epidemiology using structured statistical models.

    PubMed

    Getoor, Lise; Rhee, Jeanne T; Koller, Daphne; Small, Peter

    2004-03-01

    Molecular epidemiological studies can provide novel insights into the transmission of infectious diseases such as tuberculosis. Typically, risk factors for transmission are identified using traditional hypothesis-driven statistical methods such as logistic regression. However, limitations become apparent in these approaches as the scope of these studies expand to include additional epidemiological and bacterial genomic data. Here we examine the use of Bayesian models to analyze tuberculosis epidemiology. We begin by exploring the use of Bayesian networks (BNs) to identify the distribution of tuberculosis patient attributes (including demographic and clinical attributes). Using existing algorithms for constructing BNs from observational data, we learned a BN from data about tuberculosis patients collected in San Francisco from 1991 to 1999. We verified that the resulting probabilistic models did in fact capture known statistical relationships. Next, we examine the use of newly introduced methods for representing and automatically constructing probabilistic models in structured domains. We use statistical relational models (SRMs) to model distributions over relational domains. SRMs are ideally suited to richly structured epidemiological data. We use a data-driven method to construct a statistical relational model directly from data stored in a relational database. The resulting model reveals the relationships between variables in the data and describes their distribution. We applied this procedure to the data on tuberculosis patients in San Francisco from 1991 to 1999, their Mycobacterium tuberculosis strains, and data on contact investigations. The resulting statistical relational model corroborated previously reported findings and revealed several novel associations. These models illustrate the potential for this approach to reveal relationships within richly structured data that may not be apparent using conventional statistical approaches. We show that Bayesian

  1. The globalization of epidemiology: introductory remarks.

    PubMed

    Pearce, Neil

    2004-10-01

    We are all living in the era of globalization, and like it or not, it is going to change the way we practice epidemiology, the kinds of questions we ask, and the methods we use to answer them. Increasingly, pubic health problems are being shifted from rich countries to poor countries and from rich to poor populations within Western countries. There is increasing interest and concern about the situation in non-Western populations on the part of Western epidemiologists, with regards to collaborative research, skills transfer, and 'volunteerism' to enable the 'benefits' of Western approaches to epidemiology to be shared by the non-Western world. However, most existing collaborations benefit Western epidemiologists rather than the countries in which the research is conducted. Even when research in non-Western populations is conducted as a genuine collaboration, it can too often 'export failure' from the West. On the other hand, non-Western epidemiologists are increasingly developing new and innovative approaches to health research that are more appropriate to the global public health issues they are addressing. These include recognition of the importance of context and the importance of diversity and local knowledge, and a problem-based approach to addressing the major public health problems using appropriate technology. These debates formed the background for a plenary session on 'International Epidemiology and International Health' at the recent International Epidemiological Association (IEA) meeting in Montreal, and the papers from this session are presented here. The development of a truly global epidemiology can not only better address the public health problems in non-Western populations, but can shed light on the current limitations of epidemiology in addressing the major public health problems in the West.

  2. Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014.

    PubMed

    Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

    2015-01-01

    As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3(rd) African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities.

  3. What matters most: quantifying an epidemiology of consequence.

    PubMed

    Keyes, Katherine; Galea, Sandro

    2015-05-01

    Risk factor epidemiology has contributed to substantial public health success. In this essay, we argue, however, that the focus on risk factor epidemiology has led epidemiology to ever increasing focus on the estimation of precise causal effects of exposures on an outcome at the expense of engagement with the broader causal architecture that produces population health. To conduct an epidemiology of consequence, a systematic effort is needed to engage our science in a critical reflection both about how well and under what conditions or assumptions we can assess causal effects and also on what will truly matter most for changing population health. Such an approach changes the priorities and values of the discipline and requires reorientation of how we structure the questions we ask and the methods we use, as well as how we teach epidemiology to our emerging scholars.

  4. What matters most: quantifying an epidemiology of consequence

    PubMed Central

    Keyes, Katherine; Galea, Sandro

    2015-01-01

    Risk factor epidemiology has contributed to substantial public health success. In this essay, we argue, however, that the focus on risk factor epidemiology has led epidemiology to ever increasing focus on the estimation of precise causal effects of exposures on an outcome at the expense of engagement with the broader causal architecture that produces population health. To conduct an epidemiology of consequence, a systematic effort is needed to engage our science in a critical reflection both about how well and under what conditions or assumptions we can assess causal effects and also on what will truly matter most for changing population health. Such an approach changes the priorities and values of the discipline and requires reorientation of how we structure the questions we ask and the methods we use, as well as how we teach epidemiology to our emerging scholars. PMID:25749559

  5. myEpi. Epidemiology of One.

    PubMed

    Bobashev, Georgiy

    2014-01-01

    A new concept of within-individual epidemiology termed "myEpi" is introduced. It is argued that traditional epidemiological methods, which are usually applied to populations of humans, can be applicable to a single individual and thus used for self-monitoring and forecasting of "epidemic" outbreaks within an individual. Traditional epidemiology requires that results be generalizable to a predefined population. The key component of myEpi is that a single individual may be viewed as an entire population of events and thus, the analysis should be generalizable to this population. Applications of myEpi are aimed for, but not limited to, the analysis of data collected by individuals with the help of wearable sensors and digital diaries. These data can include physiological measures and records of healthy and risky behaviors (e.g., exercise, sleep, smoking, food consumption, alcohol, and drug use). Although many examples of within-individual epidemiology exist, there is a pressing need for systematic guidance to the analysis and interpretation of intensive individual-level data. myEpi serves this need by adapting statistical methods (e.g., regressions, hierarchical models, survival analysis, agent-based models) to individual-level data.

  6. Methods to assess seasonal effects in epidemiological studies of infectious diseases--exemplified by application to the occurrence of meningococcal disease.

    PubMed

    Christiansen, C F; Pedersen, L; Sørensen, H T; Rothman, K J

    2012-10-01

    Seasonal variation in occurrence is a common feature of many diseases, especially those of infectious origin. Studies of seasonal variation contribute to healthcare planning and to the understanding of the aetiology of infections. In this article, we provide an overview of statistical methods for the assessment and quantification of seasonality of infectious diseases, as exemplified by their application to meningococcal disease in Denmark in 1995-2011. Additionally, we discuss the conditions under which seasonality should be considered as a covariate in studies of infectious diseases. The methods considered range from the simplest comparison of disease occurrence between the extremes of summer and winter, through modelling of the intensity of seasonal patterns by use of a sine curve, to more advanced generalized linear models. All three classes of method have advantages and disadvantages. The choice among analytical approaches should ideally reflect the research question of interest. Simple methods are compelling, but may overlook important seasonal peaks that would have been identified if more advanced methods had been applied. For most studies, we suggest the use of methods that allow estimation of the magnitude and timing of seasonal peaks and valleys, ideally with a measure of the intensity of seasonality, such as the peak-to-low ratio. Seasonality may be a confounder in studies of infectious disease occurrence when it fulfils the three primary criteria for being a confounder, i.e. when both the disease occurrence and the exposure vary seasonally without seasonality being a step in the causal pathway. In these situations, confounding by seasonality should be controlled as for any confounder.

  7. Epidemiology of iodine deficiency.

    PubMed

    Vanderpump, Mark P

    2017-04-01

    Iodine is an essential component of the thyroid hormones thyroxine (T4) and triiodothyronine (T3) produced by the thyroid gland. Iodine deficiency impairs thyroid hormone production and has adverse effects throughout life, particularly early in life as it impairs cognition and growth. Iodine deficiency remains a significant problem despite major national and international efforts to increase iodine intake, primarily through the voluntary or mandatory iodization of salt. Recent epidemiological data suggest that iodine deficiency is an emerging issue in industrialized countries, previously thought of as iodine-sufficient. International efforts to control iodine deficiency are slowing, and reaching the third of the worldwide population that remains deficient poses major challenges.

  8. Epidemiologic research in Antarctica

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A study of epidemiology of respiratory viruses that was begun in the early 1960's is described. Locations selected for the study included a Wisconsin University housing village, a second grade school population, individual volunteers who associated socially, married couples, and the winter-over population at McMurdo Bay and at Scott Base in the Antarctic. It was concluded that most rhinovirus transmission is through aerosolized particles. Air filtration and careful nasal sanitation with virucidal tissues are determined to be effective in blocking rhinovirus transmission and should be useful in both isolated space colonies and in ordinary earth-bound populations.

  9. Epidemiology of tuberculosis immunology.

    PubMed

    Fox, G J; Menzies, D

    2013-01-01

    Immunological impairment plays a major role in the epidemiology of TB. Globally, the most common causes of immunological impairment are malnutrition, diabetes, HIV/AIDS, aging, and smoking. With the notable exception of HIV, each factor leads to relatively mild immunological impairment in individuals. However, as these conditions affect a significant proportion of the population, they contribute substantially to the incidence of TB at a global scale. Understanding immunological impairment is central to understanding the global TB pandemic, and vital to the development of effective disease control strategies.

  10. Epidemiology of Brain Tumors.

    PubMed

    McNeill, Katharine A

    2016-11-01

    Brain tumors are the commonest solid tumor in children, leading to significant cancer-related mortality. Several hereditary syndromes associated with brain tumors are nonfamilial. Ionizing radiation is a well-recognized risk factor for brain tumors. Several industrial exposures have been evaluated for a causal association with brain tumor formation but the results are inconclusive. A casual association between the common mutagens of tobacco, alcohol, or dietary factors has not yet been established. There is no clear evidence that the incidence of brain tumors has changed over time. This article presents the descriptive epidemiology of the commonest brain tumors of children and adults.

  11. Global epidemiology of sporotrichosis.

    PubMed

    Chakrabarti, Arunaloke; Bonifaz, Alexandro; Gutierrez-Galhardo, Maria Clara; Mochizuki, Takashi; Li, Shanshan

    2015-01-01

    Sporotrichosis is an endemic mycosis caused by the dimorphic fungus Sporothrix schenckii sensu lato. It has gained importance in recent years due to its worldwide prevalence, recognition of multiple cryptic species within the originally described species, and its distinctive ecology, distribution, and epidemiology across the globe. In this review, we describe the current knowledge of the taxonomy, ecology, prevalence, molecular epidemiology, and outbreaks due to S. schenckii sensu lato. Despite its omnipresence in the environment, this fungus has remarkably diverse modes of infection and distribution patterns across the world. We have delved into the nuances of how sporotrichosis is intimately linked to different forms of human activities, habitats, lifestyles, and environmental and zoonotic interactions. The purpose of this review is to stimulate discussion about the peculiarities of this unique fungal pathogen and increase the awareness of clinicians and microbiologists, especially in regions of high endemicity, to its emergence and evolving presentations and to kindle further research into understanding the unorthodox mechanisms by which this fungus afflicts different human populations.

  12. Molecular Epidemiology of Amebiasis

    PubMed Central

    Ali, Ibne Karim M.; Clark, C. Graham; Petri, William A.

    2008-01-01

    Entamoeba histolytica, the causative agent of human amebiasis, remains a significant cause of morbidity and mortality in developing countries and is responsible for up to 100,000 deaths worldwide each year. Entamoeba dispar, morphologically indistinguishable from E. histolytica, is more common in humans in many parts of the world. Similarly Entamoeba moshkovskii, which was long considered to be a free-living ameba, is also morphologically identical to E. histolytica and E. dispar, and is highly prevalent in some E. histolytica endemic countries. However, the only species to cause disease in humans is E. histolytica. Most old epidemiological data on E. histolytica are unusable as the techniques employed do not differentiate between the above three Entamoeba species. Molecular tools are now available not only to diagnose these species accurately but also to study intra-species genetic diversity. Recent studies suggest that only a minority of all E. histolytica infections progress to development of clinical symptoms in the host and there exist population level differences between the E. histolytica strains isolated from the asymptomatic and symptomatic individuals. Nevertheless the underlying factors responsible for variable clinical outcome of infection by E. histolytica remain largely unknown. We anticipate that the recently completed E. histolytica genome sequence and new molecular techniques will rapidly advance our understanding of the epidemiology and pathogenicity of amebiasis. PMID:18571478

  13. The Epidemiology of Sarcopenia.

    PubMed

    Dodds, Richard Matthew; Roberts, Helen Clare; Cooper, Cyrus; Sayer, Avan Aihie

    2015-01-01

    The aim of this review is to describe the epidemiology of sarcopenia, specifically prevalence, health outcomes, and factors across the life course that have been linked to its development. Sarcopenia definitions involve a range of measures (muscle mass, strength, and physical performance), which tend to decline with age, and hence sarcopenia becomes increasingly prevalent with age. Less is known about prevalence in older people in hospital and care homes, although it is likely to be higher than in community settings. The range of measures used, and the cutpoints suggested for each, presents a challenge for comparing prevalence estimates between studies. The importance of sarcopenia is highlighted by the range of adverse health outcomes that strength and physical performance (and to a lesser extent, muscle mass) have been linked to. This is shown most strikingly by the finding of increased all-cause mortality rates among those with weaker grip strength and slower gait speed. A life course approach broadens the window for our understanding of the etiology of sarcopenia and hence the potential intervention. An example is physical activity, with increased levels across midadulthood appearing to increase muscle mass and strength in early old age. Epidemiologic studies will continue to make an important contribution to our understanding of sarcopenia and possible avenues for intervention and prevention.

  14. Methodologic Issues and Approaches to Spatial Epidemiology

    PubMed Central

    Beale, Linda; Abellan, Juan Jose; Hodgson, Susan; Jarup, Lars

    2008-01-01

    Spatial epidemiology is increasingly being used to assess health risks associated with environmental hazards. Risk patterns tend to have both a temporal and a spatial component; thus, spatial epidemiology must combine methods from epidemiology, statistics, and geographic information science. Recent statistical advances in spatial epidemiology include the use of smoothing in risk maps to create an interpretable risk surface, the extension of spatial models to incorporate the time dimension, and the combination of individual- and area-level information. Advances in geographic information systems and the growing availability of modeling packages have led to an improvement in exposure assessment. Techniques drawn from geographic information science are being developed to enable the visualization of uncertainty and ensure more meaningful inferences are made from data. When public health concerns related to the environment arise, it is essential to address such anxieties appropriately and in a timely manner. Tools designed to facilitate the investigation process are being developed, although the availability of complete and clean health data, and appropriate exposure data often remain limiting factors. PMID:18709139

  15. [The role of epidemiology in mental disorder research].

    PubMed

    Borges, Guilherme; Medina-Mora, María Elena; López-Moreno, Sergio

    2004-01-01

    which are germane to public health, for example, violence. The epidemiology of mental disorders faces great challenges in the new millennium, including a complex, changing epidemiologic scenario. Several important issues will influence the future development of mental disorder epidemiology: measurement of mental disorders and risk factors, more efficient sampling design and methods, the relationships among biological research, genetics, social studies, and epidemiology, and the interface between epidemiology and the evaluation of therapies and health services.

  16. Alzheimer's disease: insights from epidemiology.

    PubMed

    McDowell, I

    2001-06-01

    While a complete understanding of the pathogenesis of Alzheimer's disease (AD) remains elusive, many conclusions can be drawn from the numerous epidemiological studies undertaken to date. Prevalence and incidence estimates show consistency, following a roughly exponential pattern with a doubling of both parameters roughly every five years after age 65. Roughly 7% of the population aged 65 and over has AD. The clinical course of the disease is reasonably well established and mortality rates rise with increasing levels of cognitive deficit. Four risk factors for AD are firmly established: increasing age, the presence of the apolipoproteinE-epsilon4 allele, familial aggregation of cases, and Down's syndrome. Numerous other associations have been shown in some studies, but not in others. For example, women generally appear at higher risk than men, as do people with lower levels of education; depression is probably prodromal; head injury is an established risk factor, and may interact with the apoE gene; several occupational exposures appear hazardous, and exposure to aluminum in the water supply confers excess risk. Hypertension and other vascular symptoms appear to predispose to AD, which is now seen as nosologically closer to vascular dementia than was previously believed. Several apparently protective factors have been identified, although preventive trials based on these have so far shown minimal effectiveness. The use of non-steroidal anti-inflammatory drugs to treat arthritis is associated with a reduced risk of AD, as is estrogen use by post-menopausal women. Physical activity appears beneficial, as does a diet with high levels of vitamins B6, B12 and folate. while red wine in moderate quantities appears protective. This review concludes with a discussion of the strengths and limitations of current epidemiological methods for studying Alzheimer's disease.

  17. Natural sex steroids and their xenobiotic analogs in animal production: growth, carcass quality, pharmacokinetics, metabolism, mode of action, residues, methods, and epidemiology.

    PubMed

    Lone, K P

    1997-03-01

    Natural and xenobiotic compounds having sex-related actions have long been used for growth promotion and various changes in carcass quality in meat animals. The first compounds used were synthetic estrogens; however, later on a whole battery of compounds having androgenic, and progestogenic actions have also been involved. In surveying the effects of these compounds in meat-producing animals, it became clear that these drugs increase the growth rate of the treated animals and bring about changes in the carcass that are generally characterized by lower fat content and more lean mass. Extensive studies undertaken in various countries, including the European Economic Community (EEC), have shown that if used according to good husbandry practices, the meat from treated animals does not have excessive amounts of residues compared with the endogenous amount of steroid production in the animals in question and also in human beings. The banning of these compounds in the European community brought a new phenomenon of illegal or black market cocktails. These mixtures of anabolic steroids are injected into the body of the animals rather than implanted in the ears, which is the normal practice in countries where they have not yet been banned. Several screening and confirmatory methods are now available for monitoring programs. However, these programs need excessive resources in terms of manpower, funds, and proper legislation, which in underdeveloped countries is questionable, particularly in the absence of strong scientific evidence for the exercise.

  18. Application of physico-chemical typing methods for the epidemiological analysis of Salmonella enteritidis strains of phage type 25/17.

    PubMed Central

    Seltmann, G.; Voigt, W.; Beer, W.

    1994-01-01

    Eighty-nine Salmonella enteritidis phage type 25/17 strains isolated from a localized outbreak in the German state Nordrhein-Westfalen (outbreak NWI) could not be further differentiated by biochemotyping and plasmid pattern analysis. They were submitted to a complex typing system consisting of modern physico-chemical analytical procedures. In lipopolysaccharide pattern analysis the strains proved to be homogeneous. In multilocus enzyme electrophoresis, outer membrane and whole cell protein pattern (WCPP) analysis, and Fourier-transform infrared (FT-IR) spectroscopy (increasing extent of differentiation in the given order) strains deviating from each basal pattern were found. The extent of correspondence in these deviations was satisfactory. Forty-six strains of the same sero- and phage type, however, obtained from different outbreaks, were additionally typed. The results obtained with them indicate that the data of the first group were not restricted to strains from outbreak NWI, but of general validity. It was found that both WCPP and FT-IR represent valuable methods for the sub-grouping of bacteria. Images Fig. 1 Fig. 2 Fig. 3 PMID:7995351

  19. Epidemiological analysis of hemorrhagic fever with renal syndrome in China with the seasonal-trend decomposition method and the exponential smoothing model

    PubMed Central

    Ke, Guibao; Hu, Yao; Huang, Xin; Peng, Xuan; Lei, Min; Huang, Chaoli; Gu, Li; Xian, Ping; Yang, Dehua

    2016-01-01

    Hemorrhagic fever with renal syndrome (HFRS) is one of the most common infectious diseases globally. With the most reported cases in the world, the epidemic characteristics are still remained unclear in China. This paper utilized the seasonal-trend decomposition (STL) method to analyze the periodicity and seasonality of the HFRS data, and used the exponential smoothing model (ETS) model to predict incidence cases from July to December 2016 by using the data from January 2006 to June 2016. Analytic results demonstrated a favorable trend of HFRS in China, and with obvious periodicity and seasonality, the peak of the annual reported cases in winter concentrated on November to January of the following year, and reported in May and June also constituted another peak in summer. Eventually, the ETS (M, N and A) model was adopted for fitting and forecasting, and the fitting results indicated high accuracy (Mean absolute percentage error (MAPE) = 13.12%). The forecasting results also demonstrated a gradual decreasing trend from July to December 2016, suggesting that control measures for hemorrhagic fever were effective in China. The STL model could be well performed in the seasonal analysis of HFRS in China, and ETS could be effectively used in the time series analysis of HFRS in China. PMID:27976704

  20. Epidemiological analysis of the dynamic and diversity of Salmonella spp. in five German pig production clusters using pheno- and genotyping methods: an exploratory study.

    PubMed

    Niemann, J; Tietze, E; Ruddat, I; Fruth, A; Prager, R; Rabsch, W; Blaha, T; Münchhausen, C; Merle, R; Kreienbrock, L

    2015-03-23

    An exploratory study in five conventional pig production clusters was carried out to investigate the dynamic and diversity of Salmonella spp. within different production stages and sample site categories (pooled feces, direct and non-direct environment). Observing two production cycles per production cluster, a total of 1276 samples were collected along the pig production chain. Following a microbiological examination via culture, 2246 subcultures were generated out of 285 Salmonella positive samples and analysed by pheno- and genotyping methods. Based on a combination of serotyping, MLVA (multiple-locus variable-number tandem repeat (VNTR) analysis), PFGE (pulse-field gel electrophoresis) and MLST (multilocus sequence typing), an amount of 22.3% Salmonella positive samples were characterized in clonal lineages and its variants. Within each production cluster, one main clonal lineage could be identified and persisted over both production cycles with a large diversity of variants and a wide distribution in sample site categories and production stages. Results underline the importance of biosecurity with emphasis on the environment to prevent persistence and circulation of Salmonella within herds. Furthermore, the combined implementation of MLVA, PFGE and MLST with conventional culture techniques for isolate classification could be successfully applied as an effective and valuable tool for identifying similar pattern of Salmonella occurrence within pig production clusters.

  1. CEDR: Comprehensive Epidemiologic Data Resource

    SciTech Connect

    Not Available

    1993-08-01

    The Department of Energy (DOE) and its predecessor agencies have a long history of epidemiologic research programs. The main focus of these programs has been the Health and Mortality Study of the DOE work force. This epidemiologic study began in 1964 with a feasibility study of workers at the Hanford facility. Studies of other populations exposed to radiation have also been supported, including the classic epidemiologic study of radium dial painters and studies of atomic bomb survivors. From a scientific perspective, these epidemiologic research program have been productive, highly credible, and formed the bases for many radiological protection standards. Recently, there has been concern that, although research results were available, the data on which these results were based were not easily obtained by interested investigators outside DOE. Therefore, as part of an effort to integrate and broaden access to its epidemiologic information, the DOE has developed the Comprehensive Epidemiologic Data Resource (CEDR) Program. Included in this effort is the development of a computer information system for accessing the collection of CEDR data and its related descriptive information. The epidemiologic data currently available through the CEDAR Program consist of analytic data sets, working data sets, and their associated documentation files. In general, data sets are the result of epidemiologic studies that have been conducted on various groups of workers at different DOE facilities during the past 30 years.

  2. Epidemiology of infections in women.

    PubMed

    Risser, Jan M H; Risser, William L; Risser, Amanda L

    2008-12-01

    This article describes the epidemiologic profiles of sexually transmitted infections seen in US women. We present a brief description of the infectious agent, describe the epidemiology of the infection among women in terms of race/ethnicity and age (if those data are available), and present what is known about the behavioral risk factors associated with acquisition.

  3. Cancer Epidemiology Data Repository (CEDR)

    Cancer.gov

    In an effort to broaden access and facilitate efficient data sharing, the Epidemiology and Genomics Research Program (EGRP) has created the Cancer Epidemiology Data Repository (CEDR), a centralized, controlled-access database, where Investigators can deposit individual-level de-identified observational cancer datasets.

  4. The future of genetic epidemiology.

    PubMed

    Morton, N E

    1992-12-01

    Starting from a broad definition of genetic epidemiology, current developments in association, segregation, and linkage analysis of complex inheritance are considered together with integration of genetic and physical maps and resolution of genetic heterogeneity. Mitochondrial inheritance, imprinting, uniparental disomy, pregressive amplification, and gonadal mosaicism are some of the novel mechanisms discussed, with speculation about the future of genetic epidemiology.

  5. The new epidemiology of nephrolithiasis.

    PubMed

    Shoag, Jonathan; Tasian, Greg E; Goldfarb, David S; Eisner, Brian H

    2015-07-01

    Historically nephrolithiasis was considered a disease of dehydration and abnormal urine composition. However, over the past several decades, much has been learned about the epidemiology of this disease and its relation to patient demographic characteristics and common systemic diseases. Here we review the latest epidemiologic studies in the field.

  6. The Epidemiology of Sarcoma

    PubMed Central

    2012-01-01

    Sarcomas account for over 20% of all pediatric solid malignant cancers and less than 1% of all adult solid malignant cancers. The vast majority of diagnosed sarcomas will be soft tissue sarcomas, while malignant bone tumors make up just over 10% of sarcomas. The risks for sarcoma are not well-understood. We evaluated the existing literature on the epidemiology and etiology of sarcoma. Risks for sarcoma development can be divided into environmental exposures, genetic susceptibility, and an interaction between the two. HIV-positive individuals are at an increased risk for Kaposi’s sarcoma, even though HHV8 is the causative virus. Radiation exposure from radiotherapy has been strongly associated with secondary sarcoma development in certain cancer patients. In fact, the risk of malignant bone tumors increases as the cumulative dose of radiation to the bone increases (p for trend <0.001). A recent meta-analysis reported that children with a history of hernias have a greater risk of developing Ewing’s sarcoma (adjusted OR 3.2, 95% CI 1.9, 5.7). Bone development during pubertal growth spurts has been associated with osteosarcoma development. Occupational factors such as job type, industry, and exposures to chemicals such as herbicides and chlorophenols have been suggested as risk factors for sarcomas. A case-control study found a significant increase in soft tissue sarcoma risk among gardeners (adjusted OR 4.1, 95% CI 1.00, 14.00), but not among those strictly involved in farming. A European-based study reported an increased risk in bone tumors among blacksmiths, toolmakers, or machine-tool operators (adjusted OR 2.14, 95% CI 1.08, 4.26). Maternal and paternal characteristics such as occupation, age, smoking status, and health conditions experienced during pregnancy also have been suggested as sarcoma risk factors and would be important to assess in future studies. The limited studies we identified demonstrate significant relationships with sarcoma risk, but many of

  7. [Epidemiology of viral hepatitis].

    PubMed

    Kaić, Bernard; Vilibić-Cavlek, Tatjana; Filipović, Sanja Kurecić; Nemeth-Blazić, Tatjana; Pem-Novosel, Iva; Vucina, Vesna Visekruna; Simunović, Aleksandar; Zajec, Martina; Radić, Ivan; Pavlić, Jasmina; Glamocanin, Marica; Gjenero-Margan, Ira

    2013-10-01

    Understanding the country-specific epidemiology of disease, which may vary greatly among countries, is crucial for identifying the most appropriate preventive and control measures. An overview of the local epidemiology of viral hepatitis in Croatia is given in this paper. The overall prevalence of hepatitis B in Croatia is low (less than 2% HBsAg carriers in the general population). Hepatitis B incidence and prevalence began to decline significantly following the introduction of universal hepatitis B vaccination in 1999. Information on HBsAg seroprevalence is derived from routine testing of certain subpopulations (pregnant women, blood donors) and seroprevalence studies mostly targeted at high-risk populations. Universal childhood vaccination against hepatitis B remains the main preventive measure. We recommend testing for immunity one to two months after the third dose of hepatitis B vaccine for health-care workers. The incidence and prevalence of hepatitis C have also been declining in the general population. The main preventive measures are ensuring safety of blood products, prevention of drug abuse, and harm reduction programs for intravenous drug users. Hepatitis A incidence has declined dramatically since fifty years ago, when thousands of cases were reported annually. In the last five years, an average of twenty cases have been reported per year. The reduction of hepatitis A is a consequence of improved personal and community hygiene and sanitation. Hepatitis D has not been reported in Croatia. The risk of hepatitis D will get to be even smaller as the proportion of population vaccinated against hepatitis B builds up. Hepatitis E is reported only sporadically in Croatia, mostly in persons occupationally in contact with pigs and in travelers to endemic countries. In conclusion, Croatia is a low prevalence country for hepatitides A, B and C. Hepatitis D has not been reported to occur in Croatia and there are only sporadic cases of hepatitis E. Since hepatitis

  8. Epidemiological evidence in forensic pharmacovigilance.

    PubMed

    Persaud, Nav; Healy, David

    2012-01-01

    Until recently epidemiological evidence was not regarded as helpful in determining cause and effect. It generated associations that then had to be explained in terms of bio-mechanisms and applied to individual patients. A series of legal cases surrounding possible birth defects triggered by doxylamine (Bendectin) and connective tissue disorders linked to breast implants made it clear that in some instances epidemiological evidence might have a more important role, but the pendulum swung too far so that epidemiological evidence has in recent decades been given an unwarranted primacy, partly perhaps because it suits the interests of certain stakeholders. Older and more recent epidemiological studies on doxylamine and other antihistamines are reviewed to bring out the ambiguities and pitfalls of an undue reliance on epidemiological studies.

  9. Teaching epidemiology inside and outside the classroom.

    PubMed

    Abramson, Joseph H

    2002-01-01

    There is no single ideal way of teaching epidemiology. Teaching can take place in different situations, and its techniques and content may differ. A good teaching programme is one that is geared to its students' needs, capacity, interests and preferences, and exploits available teaching situations and techniques to provide learning opportunities that will achieve the educational objectives. This paper reviews some features of the teaching of epidemiology inside and outside the classroom. It starts with a discussion of the main factors that affect the choice of methods and then deals in turn with conventional classroom methods, laboratory teaching (problem-solving and other exercises), self-instruction, problem-oriented projects, and distance learning. Separate consideration is then given to teaching in the hospital and in the field (with special attention to teaching in a community health center).

  10. 6) Epidemiology and Control of Guatemalan Onchocerciasis

    PubMed Central

    Takaoka, Hiroyuki; Suzuki, Takeshi

    2015-01-01

    Recent studies on the epidemiology and control of Guatemalan onchocerciasis, chiefly made by the Guatemala–Japan Cooperative Project on Onchocerciasis Research and Control, are reviewed. Epidemiological features of Guatemalan onchocerciasis are summarized as to characteristic altitudinal distribution of endemic areas, disease manifestation, vector taxonomy, biology and transmission dynamic of the disease. Extensive insecticide studies in the field and laboratory demonstrate that the characteristic situations of Guatemalan streams where Simulium ochraceum, the main vector of onchocerciasis, breeds require ingenious methods of larviciding. Finally, the feasibility of an area vector control is indicated by the successful control operation in the San Vicente Pacaya Pilot Area, in which a new fixed-dose larviciding method was applied. PMID:26744576

  11. [Epidemiological examples of infectious disease spread].

    PubMed

    Schlüter, H; Kramer, M

    2001-08-01

    The globalisation of trade with animals and animal products and increase of travel transports are very important issues with respect to prevent and control animal diseases or epizootics respectively. The disease control concepts as a complex manner should be established on scientific basis and must be permanently evaluated and updated. Outbreak investigations in order to clarify the source of infection and/or the spread of animal diseases including zoonoses are important fields of activities of veterinary epidemiologists. The application of modern epidemiological methods is the precondition of a successful disease control. On selected examples of animal diseases, the use of these methods is demonstrated. It is urgently necessary to intensify the epidemiological work in applied research and practice.

  12. Evaluation of primary HPV-DNA testing in relation to visual inspection methods for cervical cancer screening in rural China: an epidemiologic and cost-effectiveness modelling study

    PubMed Central

    2011-01-01

    Background A new lower-cost rapid-throughput human papillomavirus (HPV) test (careHPV, Qiagen, Gaithersburg, USA) has been shown to have high sensitivity for the detection of high grade cervical intraepithelial neoplasia. Methods We assessed the outcomes and cost-effectiveness of careHPV screening in rural China, compared to visual inspection with acetic acid, when used alone (VIA) or in combination with Lugol's iodine (VIA/VILI). Using data on sexual behaviour, test accuracy, diagnostic practices and costs from studies performed in rural China, we estimated the cost-effectiveness ratio (CER) and associated lifetime outcomes for once-lifetime and twice-lifetime screening strategies, and for routine screening at 5-yearly, 10-yearly and IARC-recommended intervals. The optimal age range for once-lifetime screening was also assessed. Results For all strategies, the relative ordering of test technologies in reducing cervical cancer incidence and mortality was VIA (least effective); VIA/VILI; careHPV@1.0 pg/ml and careHPV@0.5 pg/ml (most effective). For once-lifetime strategies, maximum effectiveness was achieved if screening occurred between 35-50 years. Assuming a participation rate of ~70%, once-lifetime screening at age 35 years would reduce cancer mortality by 8% (for VIA) to 12% (for careHPV@0.5) over the long term, with a CER of US$557 (for VIA) to $959 (for careHPV@1.0) per life year saved (LYS) compared to no intervention; referenced to a 2008 GDP per capita in Shanxi Province of $2,975. Correspondingly, regular screening with an age-standardised participation rate of 62% (which has been shown to be achievable in this setting) would reduce cervical cancer mortality by 19-28% (for 10-yearly screening) to 43-54% (using IARC-recommended intervals), with corresponding CERs ranging from $665 (for 10-yearly VIA) to $2,269 (for IARC-recommended intervals using careHPV@1.0) per LYS. Conclusions This modelled analysis suggests that primary careHPV screening compares

  13. [Epidemiology of tuberculosis].

    PubMed

    Mjid, M; Cherif, J; Ben Salah, N; Toujani, S; Ouahchi, Y; Zakhama, H; Louzir, B; Mehiri-Ben Rhouma, N; Beji, M

    2015-01-01

    Tuberculosis is a contagious disease caused by Mycobacterium tuberculosis. It represents, according to World Health Organization (WHO), one of the most leading causes of death worldwide. With nearly 8 million new cases each year and more than 1 million deaths per year, tuberculosis is still a public health problem. Despite of the decrease in incidence, morbidity and mortality remain important partially due to co-infection with human immunodeficiency virus and emergence of resistant bacilli. All WHO regions are not uniformly affected by TB. Africa's region has the highest rates of morbidity and mortality. The epidemiological situation is also worrying in Eastern European countries where the proportion of drug-resistant tuberculosis is increasing. These regional disparities emphasize to develop screening, diagnosis and monitoring to the most vulnerable populations. In this context, the Stop TB program, developed by the WHO and its partner's, aims to reduce the burden of disease in accordance with the global targets set for 2015.

  14. Heat illness. I. Epidemiology.

    PubMed

    Ellis, F P

    1976-01-01

    Reliable information on the epidemiology of heat illness has come, until recently, mainly from the armed forces and, to a lesser extent, from some industries and civil communities. Data from the records of the British Army, Royal Navy, Royal Air Force, Indian Armed Forces, U.S. Army and forces engaged in the Arab-Israeli wars, from the South African gold mining corporations and Persian Gulf oil tankers, and from civilian communities, mainly in the U.S.A., are reviewed and discussed with particular reference to the classification of heat illness and definition of the terms used, and the effects on acclimatized and non-acclimatized personnel and on other sections of the civilian communities most at risk, i.e. the old and very young. This section concludes with an outline of the classification of acute heat illnesses from 1899 to the eighth revision of the WHO International Classification of Diseases in 1967.

  15. Epidemiology of gliomas.

    PubMed

    Ostrom, Quinn T; Gittleman, Haley; Stetson, Lindsay; Virk, Selene M; Barnholtz-Sloan, Jill S

    2015-01-01

    Gliomas are the most common type of primary intracranial tumors. Some glioma subtypes cause significant mortality and morbidity that are disproportionate to their relatively rare incidence. A very small proportion of glioma cases can be attributed to inherited genetic disorders. Many potential risk factors for glioma have been studied to date, but few provide explanation for the number of brain tumors identified. The most significant of these factors includes increased risk due to exposure to ionizing radiation, and decreased risk with history of allergy or atopic disease. The potential effect of exposure to cellular phones has been studied extensively, but the results remain inconclusive. Recent genomic analyses, using the genome-wide association study (GWAS) design, have identified several inherited risk variants that are associated with increased glioma risk. The following chapter provides an overview of the current state of research in the epidemiology of intracranial glioma.

  16. [Epidemiology of obesity].

    PubMed

    Möhr, M

    1977-05-15

    In the GDR about 20% of the males and 40% of the females were estimated to be obese. In the country obesity is more spread than in the town. Increased disablement of obese persons leads to reduction of the national income. With higher expenses for nutrition the frequency of obestiy increases. Hypophages and hyperphages are differently distributed in persons with normal weight and obese ones, so that the average establishments do not reflect the differentiated situation in nutrition. Obesity correlates with the type of structure; with increasing obesity dominate pyknomorphous tendencies of growth. Also in normal weight pyknomorphous persons have a higher proportion of fat. We should speak of obesity in such a case, when, taking into consideration biological differentiations, the normal proportion of the fat in the body is increased by more than 1/3. For epidemiological serial examinations the degrees of relative weight basing on optimum weight are a favourable basis for the classification of obesity.

  17. EPIDEMIOLOGY OF PARACOCCIDIOIDOMYCOSIS.

    PubMed

    Martinez, Roberto

    2015-09-01

    The epidemiological characteristics of paracoccidioidomycosis were reviewed and updated. The new endemic areas in Brazil were discussed in the section regarding the geographic distribution of the mycosis. Subclinical infection with Paracoccidioides brasiliensis was discussed on the basis of skin test surveys with antigens of the fungus, seroepidemiological studies, and disease cases outside Latin America. Large case series permitted a comparison of the prevalence of the mycosis in different regions, its estimated incidence and risk factors for the development of the disease. Aspects modulating the expression of the clinical forms of paracoccidioidomycosis are also presented. This review also deals with diseases associated with the mycosis, opportunistic paracoccidioidomycosis, lethality, mortality and infection and disease in animals.

  18. EPIDEMIOLOGY OF PARACOCCIDIOIDOMYCOSIS

    PubMed Central

    MARTINEZ, Roberto

    2015-01-01

    SUMMARY The epidemiological characteristics of paracoccidioidomycosis were reviewed and updated. The new endemic areas in Brazil were discussed in the section regarding the geographic distribution of the mycosis. Subclinical infection with Paracoccidioides brasiliensis was discussed on the basis of skin test surveys with antigens of the fungus, seroepidemiological studies, and disease cases outside Latin America. Large case series permitted a comparison of the prevalence of the mycosis in different regions, its estimated incidence and risk factors for the development of the disease. Aspects modulating the expression of the clinical forms of paracoccidioidomycosis are also presented. This review also deals with diseases associated with the mycosis, opportunistic paracoccidioidomycosis, lethality, mortality and infection and disease in animals. PMID:26465364

  19. Epidemiology of dental caries.

    PubMed

    Winter, G B

    1990-01-01

    The most recent epidemiological data on the prevalence of dental caries in children indicate a halting of the increasing levels in many developing countries and a continuing decrease in many highly industrialized countries of the world. However, a further fall in caries levels predicted for 5-yr-old children in the U.K. has not occurred and the decline in caries may have begun to level out. 'Polarization' of caries to a minority of high-risk individuals is occurring in the developed world, with 20-25% of children accounting for more than 50% of the disease. Socio-economic factors are important in determining the proportion of high-risk children in these countries. The multifactorial aetiology of caries allows a number of different interpretations to account for changes in the prevalence of the disease with time, in both the developing and developed countries. These changes are variously ascribed to alterations in dietary habits, especially the consumption of sugar; variations in the patterns of oral hygiene; increased contact with trace elements, especially fluoride, in the environment; changes in the ecology and/or virulence of oral and dental plaque microflora and alterations in the oral protective mechanisms including the immune status. The epidemiological evidence available on the relationship of all these social, environmental and other factors to changes in the prevalence levels of caries does not, however, fully explain all the changes that have been observed. The claim that caries is no longer a public health problem is premature, as it ignores the still high proportion of individuals with tooth decay throughout the world.

  20. Epidemiology of abortion.

    PubMed

    Tyler C

    1976-06-01

    This brief summary presents information on the epidemiology of abortion requested by IPPF. In 1975, 8% of the world's population lived in areas where the law prohibits abortion completely, and 27% lived in areas where abortions are severely restricted. Over 2 years, 40,000 hospitalizations for abortion complications were reported in such countries, with 168 deaths. 21% of women hospitalized for a diagnosis related to abortion died. In Latin America, hospitalization and death because of illegal abortion led to epidemiological studies. In Chile, surveys indicate that 1/4 women has had an abortion. Colombia data state that 10 women die/week from abortion complications. Bangladesh identified 31 abortion deaths. When related to live births occurring in the area from which the deaths were reported, the abortion mortality ratio was 19/1000,000 live births. Data from Romania showed that before 1966, when abortion was legal, there were fewer than 100 reported deaths. After 1966, when abortion was restricted, crude birth rate increased from 15-40/1000 total population. During the following 4 years, the birth rate dropped until it was below 25, but concomitant deaths due to abortion increased. In 1965, 64 abortion-related deaths occurred, whereas by 1971, abortion-related deaths increased to 364. In North America abortion deaths and number of illegal abortions decreased dramatically after 1973, when abortion became legal in the U.S. In 1972, illegal abortions led to the deaths of 41 women, but in 1974 only 5 such deaths occurred. If women with unplanned or unwanted pregnancies all underwent abortion within the 1st 8 weeks of pregnancy, 90% of the deaths due to legal abortion could be prevented.

  1. Snippets from the past: the evolution of Wade Hampton Frost's epidemiology as viewed from the American Journal of Hygiene/Epidemiology.

    PubMed

    Morabia, Alfredo

    2013-10-01

    Wade Hampton Frost, who was a Professor of Epidemiology at Johns Hopkins University from 1919 to 1938, spurred the development of epidemiologic methods. His 6 publications in the American Journal of Hygiene, which later became the American Journal of Epidemiology, comprise a 1928 Cutter lecture on a theory of epidemics, a survey-based study of tonsillectomy and immunity to Corynebacterium diphtheriae (1931), 2 papers from a longitudinal study of the incidence of minor respiratory diseases (1933 and 1935), an attack rate ratio analysis of the decline of diphtheria in Baltimore (1936), and a 1936 lecture on the age, time, and cohort analysis of tuberculosis mortality. These 6 American Journal of Hygiene /American Journal of Epidemiology papers attest that Frost's personal evolution mirrored that of the emerging "early" epidemiology: The scope of epidemiology extended beyond the study of epidemics of acute infectious diseases, and rigorous comparative study designs and their associated quantitative methods came to light.

  2. Transforming Epidemiology for 21st Century Medicine and Public Health

    SciTech Connect

    Khoury, Muin J; Lam, Tram Kim; Ioannidis, John; Hartge, Patricia; Spitz, Margaret R.; Buring, Julie E.; Chanock, Stephen J.; Tourassi, Georgia; Zauber, Ann; Schully, Sheri D

    2013-01-01

    n 2012, the National Cancer Institute (NCI) engaged the scientific community to provide a vision for cancer epidemiology in the 21st century. Eight overarching thematic recommendations, with proposed corresponding actions for consideration by funding agencies, professional societies, and the research community emerged from the collective intellectual discourse. The themes are (i) extending the reach of epidemiology beyond discovery and etiologic research to include multilevel analysis, intervention evaluation, implementation, and outcomes research; (ii) transforming the practice of epidemiology by moving toward more access and sharing of protocols, data, metadata, and specimens to foster collaboration, to ensure reproducibility and replication, and accelerate translation; (iii) expanding cohort studies to collect exposure, clinical, and other information across the life course and examining multiple health-related endpoints; (iv) developing and validating reliable methods and technologies to quantify exposures and outcomes on a massive scale, and to assess concomitantly the role of multiple factors in complex diseases; (v) integrating big data science into the practice of epidemiology; (vi) expanding knowledge integration to drive research, policy, and practice; (vii) transforming training of 21st century epidemiologists to address interdisciplinary and translational research; and (viii) optimizing the use of resources and infrastructure for epidemiologic studies. These recommendations can transform cancer epidemiology and the field of epidemiology, in general, by enhancing transparency, interdisciplinary collaboration, and strategic applications of new technologies. They should lay a strong scientific foundation for accelerated translation of scientific discoveries into individual and population health benefits.

  3. Transforming Epidemiology for 21st Century Medicine and Public Health

    PubMed Central

    Khoury, Muin J.; Lam, Tram Kim; Ioannidis, John P.A.; Hartge, Patricia; Spitz, Margaret R.; Buring, Julie E.; Chanock, Stephen J.; Croyle, Robert T.; Goddard, Katrina A.; Ginsburg, Geoffrey S.; Herceg, Zdenko; Hiatt, Robert A.; Hoover, Robert N.; Hunter, David J.; Kramer, Barnet S.; Lauer, Michael S.; Meyerhardt, Jeffrey A.; Olopade, Olufunmilayo I.; Palmer, Julie R.; Sellers, Thomas A.; Seminara, Daniela; Ransohoff, David F.; Rebbeck, Timothy R.; Tourassi, Georgia; Winn, Deborah M.; Zauber, Ann; Schully, Sheri D.

    2013-01-01

    In 2012, the National Cancer Institute (NCI) engaged the scientific community to provide a vision for cancer epidemiology in the 21st century. Eight overarching thematic recommendations, with proposed corresponding actions for consideration by funding agencies, professional societies, and the research community emerged from the collective intellectual discourse. The themes are (i) extending the reach of epidemiology beyond discovery and etiologic research to include multilevel analysis, intervention evaluation, implementation, and outcomes research; (ii) transforming the practice of epidemiology by moving towards more access and sharing of protocols, data, metadata, and specimens to foster collaboration, to ensure reproducibility and replication, and accelerate translation; (iii) expanding cohort studies to collect exposure, clinical and other information across the life course and examining multiple health-related endpoints; (iv) developing and validating reliable methods and technologies to quantify exposures and outcomes on a massive scale, and to assess concomitantly the role of multiple factors in complex diseases; (v) integrating “big data” science into the practice of epidemiology; (vi) expanding knowledge integration to drive research, policy and practice; (vii) transforming training of 21st century epidemiologists to address interdisciplinary and translational research; and (viii) optimizing the use of resources and infrastructure for epidemiologic studies. These recommendations can transform cancer epidemiology and the field of epidemiology in general, by enhancing transparency, interdisciplinary collaboration, and strategic applications of new technologies. They should lay a strong scientific foundation for accelerated translation of scientific discoveries into individual and population health benefits. PMID:23462917

  4. Transforming epidemiology for 21st century medicine and public health.

    PubMed

    Khoury, Muin J; Lam, Tram Kim; Ioannidis, John P A; Hartge, Patricia; Spitz, Margaret R; Buring, Julie E; Chanock, Stephen J; Croyle, Robert T; Goddard, Katrina A; Ginsburg, Geoffrey S; Herceg, Zdenko; Hiatt, Robert A; Hoover, Robert N; Hunter, David J; Kramer, Barnet S; Lauer, Michael S; Meyerhardt, Jeffrey A; Olopade, Olufunmilayo I; Palmer, Julie R; Sellers, Thomas A; Seminara, Daniela; Ransohoff, David F; Rebbeck, Timothy R; Tourassi, Georgia; Winn, Deborah M; Zauber, Ann; Schully, Sheri D

    2013-04-01

    In 2012, the National Cancer Institute (NCI) engaged the scientific community to provide a vision for cancer epidemiology in the 21st century. Eight overarching thematic recommendations, with proposed corresponding actions for consideration by funding agencies, professional societies, and the research community emerged from the collective intellectual discourse. The themes are (i) extending the reach of epidemiology beyond discovery and etiologic research to include multilevel analysis, intervention evaluation, implementation, and outcomes research; (ii) transforming the practice of epidemiology by moving toward more access and sharing of protocols, data, metadata, and specimens to foster collaboration, to ensure reproducibility and replication, and accelerate translation; (iii) expanding cohort studies to collect exposure, clinical, and other information across the life course and examining multiple health-related endpoints; (iv) developing and validating reliable methods and technologies to quantify exposures and outcomes on a massive scale, and to assess concomitantly the role of multiple factors in complex diseases; (v) integrating "big data" science into the practice of epidemiology; (vi) expanding knowledge integration to drive research, policy, and practice; (vii) transforming training of 21st century epidemiologists to address interdisciplinary and translational research; and (viii) optimizing the use of resources and infrastructure for epidemiologic studies. These recommendations can transform cancer epidemiology and the field of epidemiology, in general, by enhancing transparency, interdisciplinary collaboration, and strategic applications of new technologies. They should lay a strong scientific foundation for accelerated translation of scientific discoveries into individual and population health benefits.

  5. Invited commentary: do-it-yourself modern epidemiology--at last!

    PubMed

    Morabia, Alfredo

    2014-10-01

    In this issue of the Journal, Keyes and Galea (Am J Epidemiol. 2014;180(7):661-668) propose "7 foundational steps" for introducing epidemiologic methods and concepts to beginners. Keyes and Galea's credo is that the methododological and conceptual components that comprise epidemiology, today scattered in textbook chapters, come together as an integrated and coherent methodological corpus in the process of designing studies. Thus, they expound, the process of designing studies should be the core of teaching epidemiology. Two aspects of their 7-steps-to-epidemiology, do-it-yourself user manual stand out as novel: 1) the approach, because of its emphasis on modern epidemiology's causal framework of a dynamic population in a steady state evolving across time, and 2) the ambition to teach modern epidemiology in introductory courses, instead of the popular mix of classical and modern epidemiology that is often used today to keep introductory courses simple. Both aspects are of potentially great significance for our discipline.

  6. Epidemiologic methods for investigating male fecundity

    PubMed Central

    Olsen, Jørn; Ramlau-Hansen, Cecilia Høst

    2014-01-01

    Fertility is a couple concept that has been measured since the beginning of demography, and male fecundity (his biological capacity to reproduce) is a component of the fertility rate. Unfortunately, we have no way of measuring the male component directly, although several indirect markers can be used. Population registers can be used to monitor the proportion of childless couples, couples who receive donor semen, trends in dizygotic twinning, and infertility diagnoses. Studies using time-to-pregnancy (TTP) may identify couple subfecundity, and TTP data will correlate with sperm quality and quantity as well as sexual activity and a number of other conditions. Having exposure data available for couples with a fecund female partner would make TTP studies of interest in identifying exposures that may affect male fecundity. Biological indicators such as sperm quality and quantity isolate the male component of fertility, and semen data therefore remain an important source of information for research. Unfortunately, often over half of those invited to provide a sperm sample will refuse, and the study is then subject to a selection that may introduce bias. Because the most important time windows for exposures that impair semen production could be early fetal life, puberty, and the time of ejaculation; longitudinal data over decades of time are required. The ongoing monitoring of semen quality and quantity should continue, and surveys monitoring fertility and waiting TTP should also be designed. PMID:24369129

  7. The epidemiology of premature ejaculation.

    PubMed

    Saitz, Theodore Robert; Serefoglu, Ege Can

    2016-08-01

    Vast advances have occurred over the past decade with regards to understanding the epidemiology, pathophysiology and management of premature ejaculation (PE); however, we still have much to learn about this common sexual problem. As a standardized evidence-based definition of PE has only recently been established, the reported prevalence rates of PE prior to this definition have been difficult to interpret. As a result, a large range of conflicting prevalence rates have been reported. In addition to the lack of a standardized definition and operational criteria, the method of recruitment for study participation and method of data collection have obviously contributed to the broad range of reported prevalence rates. The new criteria and classification of PE will allow for continued research into the diverse phenomenology, etiology and pathogenesis of the disease to be conducted. While the absolute pathophysiology and true prevalence of PE remains unclear, developing a better understanding of the true prevalence of the disease will allow for the completion of more accurate analysis and treatment of the disease.

  8. The epidemiology of premature ejaculation

    PubMed Central

    Saitz, Theodore Robert

    2016-01-01

    Vast advances have occurred over the past decade with regards to understanding the epidemiology, pathophysiology and management of premature ejaculation (PE); however, we still have much to learn about this common sexual problem. As a standardized evidence-based definition of PE has only recently been established, the reported prevalence rates of PE prior to this definition have been difficult to interpret. As a result, a large range of conflicting prevalence rates have been reported. In addition to the lack of a standardized definition and operational criteria, the method of recruitment for study participation and method of data collection have obviously contributed to the broad range of reported prevalence rates. The new criteria and classification of PE will allow for continued research into the diverse phenomenology, etiology and pathogenesis of the disease to be conducted. While the absolute pathophysiology and true prevalence of PE remains unclear, developing a better understanding of the true prevalence of the disease will allow for the completion of more accurate analysis and treatment of the disease. PMID:27652213

  9. Role of data warehousing in healthcare epidemiology.

    PubMed

    Wyllie, D; Davies, J

    2015-04-01

    Electronic storage of healthcare data, including individual-level risk factors for both infectious and other diseases, is increasing. These data can be integrated at hospital, regional and national levels. Data sources that contain risk factor and outcome information for a wide range of conditions offer the potential for efficient epidemiological analysis of multiple diseases. Opportunities may also arise for monitoring healthcare processes. Integrating diverse data sources presents epidemiological, practical, and ethical challenges. For example, diagnostic criteria, outcome definitions, and ascertainment methods may differ across the data sources. Data volumes may be very large, requiring sophisticated computing technology. Given the large populations involved, perhaps the most challenging aspect is how informed consent can be obtained for the development of integrated databases, particularly when it is not easy to demonstrate their potential. In this article, we discuss some of the ups and downs of recent projects as well as the potential of data warehousing for antimicrobial resistance monitoring.

  10. Epidemiological Criminology”: Coming Full Circle

    PubMed Central

    Lanier, Mark M.

    2009-01-01

    Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose “epidemiological criminology” as a bridging framework. PMID:19150901

  11. John Snow's legacy: epidemiology without borders.

    PubMed

    Fine, Paul; Victora, Cesar G; Rothman, Kenneth J; Moore, Patrick S; Chang, Yuan; Curtis, Val; Heymann, David L; Slutkin, Gary; May, Robert M; Patel, Vikram; Roberts, Ian; Wortley, Richard; Torgerson, Carole; Deaton, Angus

    2013-04-13

    This Review provides abstracts from a meeting held at the London School of Hygiene and Tropical Medicine, on April 11-12, 2013, to celebrate the legacy of John Snow. They describe conventional and unconventional applications of epidemiological methods to problems ranging from diarrhoeal disease, mental health, cancer, and accident care, to education, poverty, financial networks, crime, and violence. Common themes appear throughout, including recognition of the importance of Snow's example, the philosophical and practical implications of assessment of causality, and an emphasis on the evaluation of preventive, ameliorative, and curative interventions, in a wide variety of medical and societal examples. Almost all self-described epidemiologists nowadays work within the health arena, and this is the focus of most of the societies, journals, and courses that carry the name epidemiology. The range of applications evident in these contributions might encourage some of these institutions to consider broadening their remits. In so doing, they may contribute more directly to, and learn from, non-health-related areas that use the language and methods of epidemiology to address many important problems now facing the world.

  12. Microtia: epidemiology and genetics.

    PubMed

    Luquetti, Daniela V; Heike, Carrie L; Hing, Anne V; Cunningham, Michael L; Cox, Timothy C

    2012-01-01

    Microtia is a congenital anomaly of the ear that ranges in severity from mild structural abnormalities to complete absence of the ear, and can occur as an isolated birth defect or as part of a spectrum of anomalies or a syndrome. Microtia is often associated with hearing loss and patients typically require treatment for hearing impairment and surgical ear reconstruction. The reported prevalence varies among regions, from 0.83 to 17.4 per 10,000 births, and the prevalence is considered to be higher in Hispanics, Asians, Native Americans, and Andeans. The etiology of microtia and the cause of this wide variability in prevalence are poorly understood. Strong evidence supports the role of environmental and genetic causes for microtia. Although some studies have identified candidate genetic variants for microtia, no causal genetic mutation has been confirmed. The application of novel strategies in developmental biology and genetics has facilitated elucidation of mechanisms controlling craniofacial development. In this paper we review current knowledge of the epidemiology and genetics of microtia, including potential candidate genes supported by evidence from human syndromes and animal models. We also discuss the possible etiopathogenesis in light of the hypotheses formulated to date: Neural crest cells disturbance, vascular disruption, and altitude.

  13. Epidemiology of delayed ejaculation

    PubMed Central

    Di Sante, Stefania; Mollaioli, Daniele; Gravina, Giovanni Luca; Ciocca, Giacomo; Limoncin, Erika; Carosa, Eleonora; Lenzi, Andrea

    2016-01-01

    A large body of literature on diminished ejaculatory disorders has been generated without the use of a clear diagnostic definition. Many studies have not distinguished between the orgasm and ejaculation disorders leading to doubtful results. Delayed ejaculation (DE) is one of the diminished ejaculatory disorders, which range from varying delays in ejaculatory latency to a complete inability to ejaculate. The present review is aimed at providing a comprehensive overview of the current knowledge on the definition and epidemiology of diminished ejaculatory disorders. We focus on the acquired diseases, such as benign prostatic hyperplasia (BPH) and specific drug regimens that may cause an iatrogenic form of ejaculatory disorder. In addition, the impact of aging is discussed since the prevalence of DE appears to be moderately but positively related to age. Finally, we also focus on the importance of the hormonal milieu on male ejaculation. To date, evidence on the endocrine control of ejaculation is derived from small clinical trials, but the evidence suggests that hormones modulate the ejaculatory process by altering its overall latency. PMID:27652226

  14. Staphylococcal epidemiology in Antarctica.

    PubMed

    Cameron, A S

    1970-03-01

    An investigation of staphylococcal epidemiology was undertaken at an Australian National Antarctic Research Expedition station during 1965-1966. It concerned the carriage of staphylococci by the men and their dogs, and the occurrence of staphylococci in the station environment. The year-long study indicated that coagulase-negative strains survived better in the Antarctic environment than coagulase-positive strains. It was demonstrated that naturally acquired coagulase-positive strains could not maintain colonization on forearm skin under the usual cold exposure experienced at Mawson station, though coagulase-negative skin strains appeared to thrive during the winter. Staphylococcus albus and S. aureus were able to persist in the anterior nares, despite the sometimes lower temperatures recorded in this micro-climate, probably because of the greater humidity and denser populations found there. The majority of the nasal carriers of S. aureus were persistent carriers, only two men in 27 being found to be occasional carriers of nasal strains, which was consistent with the observation that transfer of this pathogen from man to man is not common under Antarctic conditions. Half of the 27 sledge dogs at the station were found to carry coagulase-positive staphylococci but this did not appear to be of pathological significance to their human handlers. The local inanimate environment, including mess hut, sleeping huts and sleeping bags used on expeditions, was searched for contamination by S. aureus but none was detected.

  15. Global Epidemiology of Tuberculosis

    PubMed Central

    Glaziou, Philippe; Sismanidis, Charalambos; Floyd, Katherine; Raviglione, Mario

    2015-01-01

    Despite the availability of effective chemotherapy, tuberculosis (TB) killed 1.3 million people in 2012. Alongside HIV, it remains a top cause of death from an infectious disease. Global targets for reductions in the epidemiological burden of TB have been set for 2015 and 2050 within the context of the Millennium Development Goals (MDGs) and by the Stop TB Partnership. Achieving these targets is the focus of national and international efforts in TB control, and showing whether or not they are achieved is of major importance to guide future and sustainable investments. This article provides a short overview of sources of data to estimate TB disease burden; presents estimates of TB incidence, prevalence, and mortality in 2012 and an assessment of progress toward the 2015 targets for reductions in these indicators based on trends since 1990 and projections up to 2015; analyzes trends in TB notifications and in the implementation of the Stop TB Strategy; and considers prospects for elimination of TB after 2015. PMID:25359550

  16. Shigellosis: Epidemiology in India

    PubMed Central

    Taneja, Neelam; Mewara, Abhishek

    2016-01-01

    Shigellosis is one of the major causes of diarrhoea in India. The accurate estimates of morbidity and mortality due to shigellosis are lacking, though it is endemic in the country and has been reported to cause many outbreaks. The limited information available indicates Shigella to be an important food-borne pathogen in India. S. flexneri is the most common species, S. sonnei and non-agglutinable shigellae seem to be steadily surfacing, while S. dysenteriae has temporarily disappeared from the northern and eastern regions. Antibiotic-resistant strains of different Shigella species and serotypes have emerged all over the world. Especially important is the global emergence of multidrug resistant shigellae, notably the increasing resistance to third generation cephalosporins and fluoroquinolones, and also azithromycin. This calls for a continuous and strong surveillance of antibiotic resistance across the country for periodic updation of the local antibiograms. The prevention of shigellosis is desirable as it will substantially reduce the morbidity associated with diarrhoea in the country. Public health measures like provision of safe water and adequate sanitation are of immense importance to reduce the burden of shigellosis, however, the provision of resources to develop such an infrastructure in India is a complex issue and will take time to resolve. Thus, the scientific thrust should be focused towards development of a safe and affordable multivalent vaccine. This review is focused upon the epidemiology, disease burden and the therapeutic challenges of shigellosis in Indian perspective. PMID:27487999

  17. Tuberculosis: Epidemiology and Control

    PubMed Central

    Sulis, Giorgia; Roggi, Alberto; Matteelli, Alberto; Raviglione, Mario C.

    2014-01-01

    Tuberculosis (TB) is a major public health concern worldwide: despite a regular, although slow, decline in incidence over the last decade, as many as 8.6 million new cases and 1.3 million deaths were estimated to have occurred in 2012. TB is by all means a poverty-related disease, mainly affecting the most vulnerable populations in the poorest countries. The presence of multidrug-resistant strains of M. tuberculosis in most countries, with somewhere prevalence is high, is among the major challenges for TB control, which may hinder recent achievements especially in some settings. Early TB case detection especially in resource-constrained settings and in marginalized groups remains a challenge, and about 3 million people are estimated to remain undiagnosed or not notified and untreated. The World Health Organization (WHO) has recently launched a new global TB strategy for the “post-2015 era” aimed at “ending the global TB epidemic” by 2035. This strategy is based on the three pillars that emphasize patient-centred TB care and prevention, bold policies and supportive systems, and intensified research and innovation. This paper aims to provide an overview of the global TB epidemiology as well as of the main challenges that must be faced to eliminate the disease as a public health problem everywhere. PMID:25408856

  18. Epidemiology of severe trauma.

    PubMed

    Alberdi, F; García, I; Atutxa, L; Zabarte, M

    2014-12-01

    Major injury is the sixth leading cause of death worldwide. Among those under 35 years of age, it is the leading cause of death and disability. Traffic accidents alone are the main cause, fundamentally in low- and middle-income countries. Patients over 65 years of age are an increasingly affected group. For similar levels of injury, these patients have twice the mortality rate of young individuals, due to the existence of important comorbidities and associated treatments, and are more likely to die of medical complications late during hospital admission. No worldwide, standardized definitions exist for documenting, reporting and comparing data on severely injured trauma patients. The most common trauma scores are the Abbreviated Injury Scale (AIS), the Injury Severity Score (ISS) and the Trauma and Injury severity Score (TRISS). Documenting the burden of injury also requires evaluation of the impact of post-trauma impairments, disabilities and handicaps. Trauma epidemiology helps define health service and research priorities, contributes to identify disadvantaged groups, and also facilitates the elaboration of comparable measures for outcome predictions.

  19. The epidemiology of favism.

    PubMed

    Belsey, M A

    1973-01-01

    Favism is a potential obstacle to the use of the fava bean in the development of a locally produced, inexpensive weaning food for the Middle East and North Africa. The purposes of this study were to define the epidemiology of favism, to evaluate the advisability of using the fava bean in a weaning food, and to suggest ways of avoiding or eliminating the toxic factor in the bean. Field observations, locally acquired data, and a literature review suggested that the use of the fava bean in a weaning food would be hazardous, but that the hazard might be overcome by using certain strains of the bean or, more particularly, by using old dried beans. The disease is usually directly related in time to the harvesting and availability of fresh beans, but it is also associated with fresh dried beans. On the basis of the age distribution of the disease, patterns of bean consumption, and local food taboos it appears that the toxic factor is concentrated in the skin of the bean, that it is heat-stable, that in dried beans it decreases with age, and that it crosses into the breast milk of lactating mothers. It also appears that disease expression may be a result of the interaction of several host factors, such as nutritional status and the consumption of other foods. These observations are consistent with the results of laboratory studies, which incriminate vicine, divicine, and DOPA in the etiology of favism.

  20. The epidemiology of favism

    PubMed Central

    Belsey, Mark A.

    1973-01-01

    Favism is a potential obstacle to the use of the fava bean in the development of a locally produced, inexpensive weaning food for the Middle East and North Africa. The purposes of this study were to define the epidemiology of favism, to evaluate the advisability of using the fava bean in a weaning food, and to suggest ways of avoiding or eliminating the toxic factor in the bean. Field observations, locally acquired data, and a literature review suggested that the use of the fava bean in a weaning food would be hazardous, but that the hazard might be overcome by using certain strains of the bean or, more particularly, by using old dried beans. The disease is usually directly related in time to the harvesting and availability of fresh beans, but it is also associated with fresh dried beans. On the basis of the age distribution of the disease, patterns of bean consumption, and local food taboos it appears that the toxic factor is concentrated in the skin of the bean, that it is heat-stable, that in dried beans it decreases with age, and that it crosses into the breast milk of lactating mothers. It also appears that disease expression may be a result of the interaction of several host factors, such as nutritional status and the consumption of other foods. These observations are consistent with the results of laboratory studies, which incriminate vicine, divicine, and DOPA in the etiology of favism. PMID:4541143

  1. Rosacea: current state of epidemiology.

    PubMed

    Tan, Jerry; Berg, Mats

    2013-12-01

    Case definitions are critical in epidemiologic research. However, modern disease indicators must now consider complex data from gene-based research along with traditional clinical parameters. Rosacea is a skin disorder with multiple signs and symptoms. In individuals, these features may be multiple or one may predominate. While studies on the epidemiology of rosacea have previously been sparse, there has been a recent increase in research activity. A broader body of epidemiological information that includes a greater variety of countries beyond Northern Europe and general population-based demographics is needed. As there are operational issues in current case definitions of rosacea subtypes--rationalization and standardization--universal consistent applications in future research is also imperative. Further improvement in disease definition combining new research information along with clinical pragmatism should increase the accuracy of rosacea case ascertainment and facilitate further epidemiological research.

  2. Metabolomics and Epidemiology Working Group

    Cancer.gov

    The Metabolomics and Epidemiology (MetEpi) Working Group promotes metabolomics analyses in population-based studies, as well as advancement in the field of metabolomics for broader biomedical and public health research.

  3. Genomic Resources for Cancer Epidemiology

    Cancer.gov

    This page provides links to research resources, complied by the Epidemiology and Genomics Research Program, that may be of interest to genetic epidemiologists conducting cancer research, but is not exhaustive.

  4. Sample Cancer Epidemiology Grant Applications

    Cancer.gov

    The National Cancer Institute frequently receives questions from investigators for examples of successfully funded grant applications. Several investigators agreed to let the Epidemiology and Genomics Research Program post excerpts of their grant applications online.

  5. [Sociocultural epidemiology: an essential aproach].

    PubMed

    Hersch-Martínez, Paul

    2013-01-01

    The necessity of an inclusive epidemiological approach, capable to attend the diverse dimensions involved in health damage as a reflective phenomenon of society is analyzed. The range of perspectives involved requires an inclusive methodological scope and applicative channels, in order to deal with sanitary realities systematically related to culture and social organization. Some constitutive elements of sociocultural epidemiology are underlined, shaping an operative proposal that can enhance the relationship between disciplines and sectors regarding specific outstanding public health problems.

  6. Epidemiology of urolithiasis: an update

    PubMed Central

    Trinchieri, Alberto

    2008-01-01

    Background & Aim. Changing socio-economic conditions generated changes in the prevalence, incidence and distribution for age, sex and type of urolithiasis in terms of both the site and the chemical-physical composition of the calculi. In the latter part of the 20th century the prevalence of upper urinary tract stones was increasing in Western countries whereas endemic infantile bladder stone disease was fairly widespread in huge areas of developing countries. The aim of this paper was to update previous epidemiological reports of urolithiasis by reviewing the more recent literature. Methods. Citations were extracted using PubMed database from January 2003 through December 2007 on the basis of the key words epidemiology AND urinary calculi. Results. An increase in the prevalence and incidence of urolithiasis was described in Germany whereas data from the United States were contradictory with stone disease rates increased only for women with a change of male-to-female ratio. Prevalence figures of stone disease observed in some developing country in tropical regions were similar to rates of Western countries with incidence of renal colic particularly high in warm months. African Americans had a reduced risk of stone disease compared to other racial groups but in renal stone patients all racial groups demonstrated a similarity in the incidence of underlying metabolic abnormalities. Upper urinary tract stones in children were associated more frequently with metabolic disturbances rather than with urinary tract anomalies and infection. Endemic childhood bladder stones are still present in some developing countries. Dietary risk factors for stone disease were shown different by age and sex. In particular in younger women dietary calcium, phytate and fluid intake were associated with a reduced risk of stone formation whereas animal protein and sucrose increased the risk of stone incidence. In older adults there was no association between dietary calcium and stone formation

  7. [Epidemiology and control of rabies].

    PubMed

    Schneider, L G

    1977-09-01

    The epidemiological criteria of the present sylvatic rabies epizootic are shown using the situation in the Federal Republic of Germany and its neighbouring countries as an example. It is demonstrated that the fox plays the leading role in transmitting the disease to other animal species and remains the main vector in the epizootic. Mustelids are of secondary importance. Cervides, rodents and domestic animals are of no concern in the spread of rabies. Rabies control measures have to be aimed at the population reduction of but one species, the fox, since the frequency of rabies among this species is primarily dependent on the population density. Other wild carnivores especially badgers should be spared. Intensified shooting of foxes as a single control measure has proven ineffective. According to the results obtained in Central Europe, the gassing of fox dens, where applicable, has proven to be the best single measure regularly resulting in a decrease of rabies cases. In individual instances this has led to a complete extinction of rabies. The oral immunization of foxes is not yet regarded as acceptable; large-scale success with this method is not to be expected.

  8. Epidemiology of hip fractures.

    PubMed

    Kannus, P; Parkkari, J; Sievänen, H; Heinonen, A; Vuori, I; Järvinen, M

    1996-01-01

    There were an estimated 1.66 million hip fractures world-wide in 1990. According to the epidemiologic projections, this worldwide annual number will rise to 6.26 million by the year 2050. This rise will be in great part due to the huge increase in the elderly population of the world. However, the age-specific incidence rates of hip fractures have also increased during the recent decades and in many countries this rise has not leveled off. In the districts where this increase has either showed or leveled off, the change seems to especially concern women's cervical fractures. In men, the increase has continued unabated almost everywhere. Reasons for the age-specific increase are not known: increase in the age-adjusted incidence of falls of the elderly individuals with accompanying deterioration in the age-adjusted bone quality (strength, mineral density) may partially explain the phenomenon. The growth of the elderly population will be more marked in Asia, Latin America, the Middle East, and Africa than in Europe and North America, and it is in the former regions that the greatest increments in hip fracture are projected so that these regions will account for over 70% of the 6.26 million hip fractures in the year 2050. The incidence rates of hip fractures vary considerably from population to population and race to race but increase exponentially with age in every group. Highest incidences have been described in the whites of Northern Europe (Scandinavia) and North America. In Finland, for example, the 1991 incidence of hip fractures was 1.1% for women and 0.7% for men over 70 years of age. Among elderly nursing home residents, the figures can be as high as 6.2% and 4.9%. The lifetime risk of a hip fracture is 16%-18% in white women and 5%-6% in white men. At the age of 80 years, every fifth woman and at the age of 90 years almost every second woman has suffered a hip fracture. Since populations are aging worldwide, the mean age of the hip fracture patients are

  9. Charting a Future for Epidemiologic Training

    PubMed Central

    Samet, Jonathan M.; Chavez, Gilbert F.; Davies, Megan M.; Galea, Sandro; Hiatt, Robert A.; Hornung, Carlton A.; Khoury, Muin J.; Koo, Denise; Mays, Vickie M.; Remington, Patrick; Yarber, Laura

    2015-01-01

    Purpose To identify macro level trends that are changing the needs of epidemiologic research and practice and to develop and disseminate a set of competencies and recommendations for epidemiologic training that will be responsive to these changing needs. Methods There were three stages to the project: 1) assembly of a working group of senior epidemiologists from multiple sectors, 2) Identifying relevant literature, and 3) conducting key informant interviews with 15 experienced epidemiologists. Results Twelve macro trends were identified along with associated actions for the field and educational competencies. The macro trends include: 1) “Big Data”/ informatics, 2) the changing health communication environment, 3) the Affordable Care Act/health care system reform, 4) shifting demographics, 5) globalization, 6) emerging high throughput technologies (“omics”), 7) a greater focus on accountability, 8) privacy changes, 9) a greater focus on “upstream” causes of disease, 10) the emergence of translational sciences, 11) the growing centrality of team and trans-disciplinary science, and 12) the evolving funding environment. Conclusion Addressing these issues through curricular change is needed to allow the field of epidemiology to more fully reach and sustain its full potential to benefit population health and remain a scientific discipline that makes critical contributions to ensuring clinical, social, and population health. PMID:25976024

  10. Global epidemiology of influenza: past and present.

    PubMed

    Cox, N J; Subbarao, K

    2000-01-01

    Pandemics are the most dramatic presentation of influenza. Three have occurred in the twentieth century: the 1918 H1N1 pandemic, the 1957 H2N2 pandemic, and the 1968 H3N2 pandemic. The tools of molecular epidemiology have been applied in an attempt to determine the origin of pandemic viruses and to understand what made them such successful pathogens. An excellent example of this avenue of research is the recent phylogenetic analysis of genes of the virus that caused the devastating 1918 pandemic. This analysis has been used to identify evolutionarily related influenza virus genes as a clue to the source of the pandemic of 1918. Molecular methods have been used to investigate the avian H5N1 and H9N2 influenza viruses that recently infected humans in Hong Kong. Antigenic, genetic, and epidemiologic analyses have also furthered our understanding of interpandemic influenza. Although many questions remain, advances of the past two decades have demonstrated that several widely held concepts concerning the global epidemiology of influenza were false.

  11. Clinical, epidemiological, and therapeutic profile of dermatophytosis*

    PubMed Central

    Pires, Carla Andréa Avelar; da Cruz, Natasha Ferreira Santos; Lobato, Amanda Monteiro; de Sousa, Priscila Oliveira; Carneiro, Francisca Regina Oliveira; Mendes, Alena Margareth Darwich

    2014-01-01

    BACKGROUND The cutaneous mycoses, mainly caused by dermatophyte fungi, are among the most common fungal infections worldwide. It is estimated that 10% to 15% of the population will be infected by a dermatophyte at some point in their lives, thus making this a group of diseases with great public health importance. OBJECTIVE To analyze the clinical, epidemiological, and therapeutic profile of dermatophytosis in patients enrolled at the Dermatology service of Universidade do Estado do Pará, Brazil, from July 2010 to September 2012. METHOD A total of 145 medical records of patients diagnosed with dermatophytosis were surveyed. Data were collected and subsequently recorded according to a protocol developed by the researchers. This protocol consisted of information regarding epidemiological and clinical aspects of the disease and the therapy employed. RESULTS The main clinical form of dermatophyte infection was onychomycosis, followed by tinea corporis, tinea pedis, and tinea capitis. Furthermore, the female population and the age group of 51 to 60 years were the most affected. Regarding therapy, there was a preference for treatments that combine topical and systemic drugs, and the most widely used drugs were fluconazole (systemic) and ciclopirox olamine (topical). CONCLUSION This study showed the importance of recurrent analysis of the epidemiological profile of dermatophytosis to enable correct therapeutic and preventive management of these conditions, which have significant clinical consequences, with chronic, difficult-totreat lesions that can decrease patient quality of life and cause disfigurement. PMID:24770502

  12. Epidemiological determinants of psoriasis.

    PubMed

    Islam, M T; Paul, H K; Zakaria, S M; Islam, M M; Shafiquzzaman, M

    2011-01-01

    A cross-sectional study was conducted on 102 cases having clinical manifestation of psoriasis with a view to evaluate the epidemiological determinants of psoriasis. Psoriasis constituted 1.49% of the total dermatological disorder. Seventy patients (68.6%) were males and thirty two (31.4%) were females with a male to female ratio of 2.18:1. The mean age was 30.76±13.17 years in male and 26.94±14.94 years in female. Sixteen (15.7%) patients had one or more family member having psoriasis with male and female in equal frequency. Regarding precipitating factors, psoriasis was developed after trauma in 4.9%, infection 3.9%, stressful life events 6.9% and drugs 2.9%; and was exacerbated after trauma in 5.9%, infection 5.9%, stressful life events 35.3% and drugs 12.7%. The disease showed improvement in summer (27.5%) and found deteriorated in winter (47.1%). Sunlight had beneficial effect in 33.3% of cases. During pregnancy improvement was observed in 50% but flare up in 22.2% of cases. Fifty percent of patients were smokers, 41.2% were non-smokers and 13.7% were ex-smokers. Forty percent had Body Mass Index (BMI) between 22 to 26 Kg/m², 40.2% had less than 22 Kg/m² and 15.7% had above 26 Kg/m². It was concluded that the prevalence of psoriasis among dermatological patients was similar to results reported in Turkey and in Northern India. The precipitating factors, such as smoking, stressful life events, infection, trauma, sunlight, pregnancy, drugs, and seasonal variations could influence the development of psoriasis and affect its clinical expression.

  13. Epidemiology of Spondyloarthritis

    PubMed Central

    Stolwijk, Carmen; van Tubergen, Astrid; Reveille, John D.

    2014-01-01

    Synopsis Spondyloarthritis (SpA) represents a group of interrelated diseases with common clinical features and a close association with HLA-B27. Figures on the incidence and prevalence of diseases vary highly dependent on methodological differences between studies, the case definition used to classify disease and on the prevalence of HLA-B27 in the population studied. When summarizing the available literature, incidence rates of SpA are mainly based on the ESSG criteria and range between 0.48 and 63/100.000 while prevalence rates vary between 0.01 and 2.5%. For ankylosing spondylitis (AS), the most widely recognized representative of the SpA group of diseases, incidence rates of 0.44-7.3/100.000 and prevalence rates of 0.007-1.7% have been described in studies that were based on the (modified) New York criteria to classify cases. The incidence of psoriatic arthritis (PsA) varied from 3.6 up to 23.1/100.000 in different studies and prevalence between <0.1% and 0.4%, using a variety of classification criteria. The incidence of ReA has been estimated between 0.6 up to 28/100.000 in studies based on different source populations and different case definitions. The newly proposed criteria for axial SpA and peripheral SpA present an attractive new approach to facilitate classification of the SpA into two main subtypes and the axial SpA criteria allow earlier detection of patents with inflammatory back pain. It should be emphasized that these criteria were developed for use in a (specialized) clinical setting and not for large epidemiological studies. PMID:23083748

  14. Defining Chronic Cough: A Systematic Review of the Epidemiological Literature

    PubMed Central

    Song, Woo-Jung; Chang, Yoon-Seok; Faruqi, Shoaib; Kang, Min-Koo; Kim, Ju-Young; Kang, Min-Gyu; Kim, Sujeong; Jo, Eun-Jung; Lee, Seung-Eun; Kim, Min-Hye; Plevkova, Jana; Park, Heung-Woo

    2016-01-01

    Purpose Recent evidence suggests a global burden of chronic cough in general populations. However, the definitions vary greatly among epidemiological studies, and none have been validated for clinical relevance. We aimed to examine previous epidemiological definitions in detail and explore the operational characteristics. Methods A systematic review was conducted for epidemiological surveys that reported the prevalence of chronic cough in general adult populations during the years 1980 to 2013. A literature search was performed on Pubmed and Embase without language restriction. Epidemiological definitions for chronic cough were classified according to their components, such as cutoff duration. Meta-analyses were performed for the male-to-female ratio of chronic cough prevalence to explore operational characteristics of epidemiological definitions. Results A total of 70 studies were included in the systematic review. The most common epidemiological definition was identified as 'cough ≥3 months' duration without specification of phlegm (n=50); however, it conflicted with the cutoff duration in current clinical guidelines (cough ≥8 weeks). Meta-analyses were performed for the male-to-female ratio of chronic cough among 28 studies that reported sex-specific prevalence using the most common definition. The pooled male-to-female odds ratio was 1.26 (95% confidence interval 0.92-1.73) with significant heterogeneity (I2=96%, P<0.001), which was in contrast to clinical observations of female predominance from specialist clinics. Subgroup analyses did not reverse the ratio or reduce the heterogeneity. Conclusions This study identified major issues in defining chronic cough in future epidemiological studies. The conflict between epidemiological and clinical diagnostic criteria needs to be resolved. The unexpected difference in the gender predominance between the community and clinics warrants further studies. Clinical validation of the existing definition is required

  15. Protecting Privacy of Shared Epidemiologic Data without Compromising Analysis Potential

    PubMed Central

    Cologne, John; Grant, Eric J.; Nakashima, Eiji; Chen, Yun; Funamoto, Sachiyo; Katayama, Hiroaki

    2012-01-01

    Objective. Ensuring privacy of research subjects when epidemiologic data are shared with outside collaborators involves masking (modifying) the data, but overmasking can compromise utility (analysis potential). Methods of statistical disclosure control for protecting privacy may be impractical for individual researchers involved in small-scale collaborations. Methods. We investigated a simple approach based on measures of disclosure risk and analytical utility that are straightforward for epidemiologic researchers to derive. The method is illustrated using data from the Japanese Atomic-bomb Survivor population. Results. Masking by modest rounding did not adequately enhance security but rounding to remove several digits of relative accuracy effectively reduced the risk of identification without substantially reducing utility. Grouping or adding random noise led to noticeable bias. Conclusions. When sharing epidemiologic data, it is recommended that masking be performed using rounding. Specific treatment should be determined separately in individual situations after consideration of the disclosure risks and analysis needs. PMID:22505949

  16. Protecting Privacy of Shared Epidemiologic Data without Compromising Analysis Potential

    DOE PAGES

    Cologne, John; Grant, Eric J.; Nakashima, Eiji; ...

    2012-01-01

    Objective . Ensuring privacy of research subjects when epidemiologic data are shared with outside collaborators involves masking (modifying) the data, but overmasking can compromise utility (analysis potential). Methods of statistical disclosure control for protecting privacy may be impractical for individual researchers involved in small-scale collaborations. Methods . We investigated a simple approach based on measures of disclosure risk and analytical utility that are straightforward for epidemiologic researchers to derive. The method is illustrated using data from the Japanese Atomic-bomb Survivor population. Results . Masking by modest rounding did not adequately enhance security but rounding to remove several digits ofmore » relative accuracy effectively reduced the risk of identification without substantially reducing utility. Grouping or adding random noise led to noticeable bias. Conclusions . When sharing epidemiologic data, it is recommended that masking be performed using rounding. Specific treatment should be determined separately in individual situations after consideration of the disclosure risks and analysis needs.« less

  17. Confidence intervals for effect parameters common in cancer epidemiology.

    PubMed Central

    Sato, T

    1990-01-01

    This paper reviews approximate confidence intervals for some effect parameters common in cancer epidemiology. These methods have computational feasibility and give nearly nominal coverage rates. In the analysis of crude data, the simplest type of epidemiologic analysis, parameters of interest are the odds ratio in case-control studies and the rate ratio and difference in cohort studies. These parameters can estimate the instantaneous-incidence-rate ratio and difference that are the most meaningful effect measures in cancer epidemiology. Approximate confidence intervals for these parameters including the classical Cornfield's method are mainly based on efficient scores. When some confounding factors exist, stratified analysis and summary measures for effect parameters are needed. Since the Mantel-Haenszel estimators have been widely used by epidemiologists as summary measures, confidence intervals based on the Mantel-Haenszel estimators are described. The paper also discusses recent developments in these methods. PMID:2269246

  18. [METHODICAL APPROACHES, EXPERIENCE AND PERSPECTIVES OF THE IMPLEMENTATION OF THE RISK MODEL OF SURVEILLANCE ACTIVITIES IN THE SPHERE OF THE ASSURANCE OF SANITARY AND EPIDEMIOLOGICAL WELFARE OF POPULATION, POPULATION'S HEALTH RISK MANAGEMENT AND THE CONSUMER RIGHTS PROTECTION].

    PubMed

    Gurvich, V B; Kuz'min, S V; Dikonskaia, O V; Gileva, M A; Boiarskiĭ, A P

    2015-01-01

    Control and supervision measures--one of the main technologies of Federal Service for Supervision of Consumer Rights protection and Human Welfare in the overall system of risk management for public health and damage to property consumers, aimed at the solution of the prior tasks in the field of assurance of the sanitary and epidemiological welfare of the population and consumer rights protection. The effectiveness of this technology depends on the correct choice of priority objects of supervision, which form the main problems in the sanitary and epidemiological situation and in the consumer market. The application of is approach has led to more effective oversight activity and the improvement of a number of indices characterizing the achievement of the objectives in the common system of risk management for public health and property of consumers.

  19. A Bayesian Ensemble Approach for Epidemiological Projections

    PubMed Central

    Lindström, Tom; Tildesley, Michael; Webb, Colleen

    2015-01-01

    Mathematical models are powerful tools for epidemiology and can be used to compare control actions. However, different models and model parameterizations may provide different prediction of outcomes. In other fields of research, ensemble modeling has been used to combine multiple projections. We explore the possibility of applying such methods to epidemiology by adapting Bayesian techniques developed for climate forecasting. We exemplify the implementation with single model ensembles based on different parameterizations of the Warwick model run for the 2001 United Kingdom foot and mouth disease outbreak and compare the efficacy of different control actions. This allows us to investigate the effect that discrepancy among projections based on different modeling assumptions has on the ensemble prediction. A sensitivity analysis showed that the choice of prior can have a pronounced effect on the posterior estimates of quantities of interest, in particular for ensembles with large discrepancy among projections. However, by using a hierarchical extension of the method we show that prior sensitivity can be circumvented. We further extend the method to include a priori beliefs about different modeling assumptions and demonstrate that the effect of this can have different consequences depending on the discrepancy among projections. We propose that the method is a promising analytical tool for ensemble modeling of disease outbreaks. PMID:25927892

  20. The epidemiology of rheumatoid arthritis.

    PubMed

    Gabriel, S E

    2001-05-01

    Studies of the descriptive epidemiology of RA indicate a population prevalence of 0.5% to 1% and a highly variable annual incidence (12-1200 per 100,000 population) depending on gender, race/ethnicity, and calendar year. Secular trends in RA incidence over time have been shown in several studies, supporting the hypothesis of a host-environment interaction. People with RA have a significantly increased risk of death compared with age- and sex-matched controls without RA from the same community. The determinants of this excess mortality remain unclear; however, reports suggest increased risk from gastrointestinal, respiratory, cardiovascular, infectious, and hematologic diseases among RA patients compared with controls. Despite extensive epidemiologic research, the etiology of RA is unknown. Several risk factors have been suggested as important in the development or progression of RA. These include genetics, infectious agents, oral contraceptives, smoking, and formal education. Epidemiologic research is an essential contributor to our understanding of RA.

  1. Multiple Sclerosis Epidemiology in Europe.

    PubMed

    Bezzini, Daiana; Battaglia, Mario A

    2017-01-01

    Multiple sclerosis is characterized by a non-homogeneous distribution around the world. Some authors in past described a latitude gradient, with increasing risk from the equator to North and South Poles, but this theory is still controversial. Regarding Europe, there are many articles in the literature concerning the epidemiology of this disease but, unfortunately, they are not always comparable due to different methodologies, they do not cover all countries in the continent, and most of them reported data of small areas and rarely at a national level. In 2012 there were 20 national registries that could help to describe the epidemiology of the disease and, in addition, there is an European Register for Multiple Sclerosis that collect data from already existing national or regional MS registries and databases. Another valid alternative to obtain epidemiological data, also at national level, in a routinely and cost-saving way is through administrative data that are of increasing interest in the last years.

  2. Epidemiologic problems associated with exposure to several agents.

    PubMed Central

    Waxweiler, R J

    1981-01-01

    Simultaneous exposure to many potentially hazardous agents in the environment is the rule, yet there have been few studies that have addressed the issue of interactions of these agents in modifying disease outcomes, even though such interactions may potentially be important in terms of policy-making. Epidemiological methods may be an important way to identify interaction effects, especially for chronic disease outcomes. Some examples of epidemiologic investigations of this problem are given, and a matrix method used to evaluate the contribution of nineteen chemicals to the risk of liver angiosarcoma in vinyl chloride workers is discussed. PMID:7199433

  3. Genetic epidemiology, genetic maps and positional cloning.

    PubMed Central

    Morton, Newton E

    2003-01-01

    Genetic epidemiology developed in the middle of the last century, focused on inherited causes of disease but with methods and results applicable to other traits and even forensics. Early success with linkage led to the localization of genes contributing to disease, and ultimately to the Human Genome Project. The discovery of millions of DNA markers has encouraged more efficient positional cloning by linkage disequilibrium (LD), using LD maps and haplotypes in ways that are rapidly evolving. This has led to large international programmes, some promising and others alarming, with laws about DNA patenting and ethical guidelines for responsible research still struggling to be born. PMID:14561327

  4. Descriptive Epidemiology of Cervical Dystonia

    PubMed Central

    Defazio, Giovanni; Jankovic, Joseph; Giel, Jennifer L.; Papapetropoulos, Spyridon

    2013-01-01

    Background Cervical dystonia (CD), the most common form of adult-onset focal dystonia, has a heterogeneous clinical presentation with variable clinical features, leading to difficulties and delays in diagnosis. Owing to the lack of reviews specifically focusing on the frequency of primary CD in the general population, we performed a systematic literature search to examine its prevalence/incidence and analyze methodological differences among studies. Methods We performed a systematic literature search to examine the prevalence data of primary focal CD. Sixteen articles met our methodological criteria. Because the reported prevalence estimates were found to vary widely across studies, we analyzed methodological differences and other factors to determine whether true differences exist in prevalence rates among geographic areas (and by gender and age distributions), as well as to facilitate recommendations for future studies. Results Prevalence estimates ranged from 20–4,100 cases/million. Generally, studies that relied on service-based and record-linkage system data likely underestimated the prevalence of CD, whereas population-based studies suffered from over-ascertainment. The more methodologically robust studies yielded a range of estimates of 28–183 cases/million. Despite the varying prevalence estimates, an approximate 2:1 female:male ratio was consistent among many studies. Three studies estimated incidence, ranging from 8–12 cases/million person-years. Discussion Although several studies have attempted to estimate the prevalence and incidence of CD, there is a need for additional well-designed epidemiological studies on primary CD that include large populations; use defined CD diagnostic criteria; and stratify for factors such as age, gender, and ethnicity. PMID:24255801

  5. Epidemiology of Bluetongue in India.

    PubMed

    Rao, P P; Hegde, N R; Reddy, Y N; Krishnajyothi, Y; Reddy, Y V; Susmitha, B; Gollapalli, S R; Putty, K; Reddy, G H

    2016-04-01

    Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in domestic and wild ruminants, the clinical disease and mortality are observed only in sheep, especially in the southern states of the country. The difference in disease patterns in different parts of the country could be due to varied climatic conditions, sheep population density and susceptibility of the sheep breeds to BT. Over the five decades after the first report of BT in 1964, most of the known serotypes of bluetongue virus (BTV) have been reported from India either by virus isolation or by detection of serotype-specific antibodies. There have been no structured longitudinal studies to identify the circulating serotypes throughout the country. At least ten serotypes were isolated between 1967 and 2000 (BTV-1-4, 6, 9, 16-18, 23). Since 2001, the All-India Network Programme on Bluetongue and other laboratories have isolated eight different serotypes (BTV-1-3, 9, 10, 12, 16, 21). Genetic analysis of these viruses has revealed that some of them vary substantially from reference viruses, and some show high sequence identity with modified live virus vaccines used in different parts of the world. These observations have highlighted the need to develop diagnostic capabilities, especially as BT outbreaks are still declared based on clinical signs. Although virus isolation and serotyping are the gold standards, rapid methods based on the detection of viral nucleic acid may be more suitable for India. The epidemiological investigations also have implications for vaccine design. Although only a handful serotypes may be involved in causing outbreaks every year, the combination of serotypes may change from year to year. For effective control of BT in India, it may be pertinent to introduce sentinel and vector traps systems for identification of the circulating serotypes and to evaluate herd immunity against different serotypes, so that relevant strains can be included in vaccine

  6. Cannabis Epidemiology: A Selective Review

    PubMed Central

    Anthony, James C.; Lopez-Quintero, Catalina; Alshaarawy, Omayma

    2017-01-01

    Background Globally, the most widely used set of compounds among the internationally regulated drugs is cannabis. Objective To review evidence from epidemiological research on cannabis, organized in relation to this field’s five main rubrics: quantity, location, causes, mechanisms, and prevention/control. Method The review covers a selection of evidence from standardized population surveys, official statistics, and governmental reports, as well as published articles and books identified via MEDLINE, Web of Science, and Google Scholar as of July 2016. Results In relation to quantity, an estimated 3% to 5% of the world population is thought to have tried a cannabis product, with at least one fairly recent use, mainly extra-medical and outside boundaries of prescribed use. Among cannabis users in the United States, roughly one in 7–8 has engaged in medical marijuana use. In relation to location, prevalence proportions reveal important variations across countries and between subgroups within countries. Regarding causes and mechanisms of starting to use cannabis, there is no compelling integrative and replicable conceptual model or theoretical formulation. Most studies of mechanisms have focused upon a ‘gateway sequence’ and person-to-person diffusion, with some recent work on disability-adjusted life years. A brief review of cannabis use consequences, as well as prevention and control strategies is also provided. Conclusion At present, we know much about the frequency and occurrence of cannabis use, with too little replicable definitive evidence with respect to the other main rubrics. Given a changing regulatory environment for cannabis products, new institutions such as an independent International Cannabis Products Safety Commission may be required to produce evidence required to weigh benefits versus costs. It is not clear that government sponsored research will be sufficient to meet consumer demand for balanced points of view and truly definitive evidence

  7. AIR POLLUTION EPIDEMIOLOGY: CAN INFORMATION BE OBTAINED FROM THE VARIATIONS IN SIGNIFICANCE AND RISK AS A FUNCTION OF DAYS AFTER EXPOSURE (LAG STRUCTURE)?

    EPA Science Inventory

    Determine if analysis of lag structure from time series epidemiology, using gases, particles, and source factor time series, can contribute to understanding the relationships among various air pollution indicators. Methods: Analyze lag structure from an epidemiologic study of ca...

  8. Methods and Technologies Branch (MTB)

    Cancer.gov

    The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.

  9. Introduction to the use of regression models in epidemiology.

    PubMed

    Bender, Ralf

    2009-01-01

    Regression modeling is one of the most important statistical techniques used in analytical epidemiology. By means of regression models the effect of one or several explanatory variables (e.g., exposures, subject characteristics, risk factors) on a response variable such as mortality or cancer can be investigated. From multiple regression models, adjusted effect estimates can be obtained that take the effect of potential confounders into account. Regression methods can be applied in all epidemiologic study designs so that they represent a universal tool for data analysis in epidemiology. Different kinds of regression models have been developed in dependence on the measurement scale of the response variable and the study design. The most important methods are linear regression for continuous outcomes, logistic regression for binary outcomes, Cox regression for time-to-event data, and Poisson regression for frequencies and rates. This chapter provides a nontechnical introduction to these regression models with illustrating examples from cancer research.

  10. Sustainable agriculture and plant diseases: an epidemiological perspective.

    PubMed

    Gilligan, Christopher A

    2008-02-27

    The potential for modern biology to identify new sources for genetical, chemical and biological control of plant disease is remarkably high. Successful implementation of these methods within globally and locally changing agricultural environments demands new approaches to durable control. This, in turn, requires fusion of population genetics and epidemiology at a range of scales from the field to the landscape and even to continental deployment of control measures. It also requires an understanding of economic and social constraints that influence the deployment of control. Here I propose an epidemiological framework to model invasion, persistence and variability of epidemics that encompasses a wide range of scales and topologies through which disease spreads. By considering how to map control methods onto epidemiological parameters and variables, some new approaches towards optimizing the efficiency of control at the landscape scale are introduced. Epidemiological strategies to minimize the risks of failure of chemical and genetical control are presented and some consequences of heterogeneous selection pressures in time and space on the persistence and evolutionary changes of the pathogen population are discussed. Finally, some approaches towards embedding epidemiological models for the deployment of control in an economically plausible framework are presented.

  11. Trichloroethylene Cancer Epidemiology: A Consideration of Select Issues

    PubMed Central

    Scott, Cheryl Siegel; Chiu, Weihsueh A.

    2006-01-01

    A large body of epidemiologic evidence exists for exploring causal associations between cancer and trichloroethylene (TCE) exposure. The U.S. Environmental Protection Agency 2001 draft TCE health risk assessment concluded that epidemiologic studies, on the whole, support associations between TCE exposure and excess risk of kidney cancer, liver cancer, and lymphomas, and, to a lesser extent, cervical cancer and prostate cancer. As part of a mini-monograph on key issues in the health risk assessment of TCE, this article reviews recently published scientific literature examining cancer and TCE exposure and identifies four issues that are key to interpreting the larger body of epidemiologic evidence: a) relative sensitivity of cancer incidence and mortality data; b) different classifications of lymphomas, including non-Hodgkin lymphoma; c) differences in data and methods for assigning TCE exposure status; and d) different methods employed for causal inferences, including statistical or meta-analysis approaches. The recent epidemiologic studies substantially expand the epidemiologic database, with seven new studies available on kidney cancer and somewhat fewer studies available that examine possible associations at other sites. Overall, recently published studies appear to provide further support for the kidney, liver, and lymphatic systems as targets of TCE toxicity, suggesting, as do previous studies, modestly elevated (typically 1.5–2.0) site-specific relative risks, given exposure conditions in these studies. However, a number of challenging issues need to be considered before drawing causal conclusions about TCE exposure and cancer from these data. PMID:16966107

  12. JPRS Report, Epidemiology.

    DTIC Science & Technology

    1989-05-08

    situation worthy of the pen of Saltykov -Shchedrin, but perhaps of Dostoevsky as well. That which had been declared illegal was simultaneously declared to... methods of detection cannot identify virus carri- ers in the first months following infection, and yet their blood is already contaminated. The ukase of...considerably. When the body becomes emaciated, the level of HIV antibodies also decreases sharply and cannot be deter- mined with the sampling methods

  13. JPRS Report, Epidemiology.

    DTIC Science & Technology

    1989-02-02

    immunoassay employing the Abbott HTLV -III and Abbott HTLV -III confirmatory El A kits and by the immune blotting method. All of the patients in the hospital...1987. On that same day antibodies to HIV had been detected in an enzyme immunoassay and subse- quently confirmed in the immune blotting test. The...only. The immune blotting method was used to test the blood serum of 16 out of the 19 antibody carriers. All 16 patients were found to have serum

  14. Assessment of mechanical exposure in ergonomic epidemiology

    PubMed Central

    van der Beek, A. J.; Frings-Dresen, M. H.

    1998-01-01

    In recent years several different methods have been developed to assess mechanical exposures, which are related to musculoskeletal disorders in ergonomic epidemiology. Each of these methods is capable of measuring one or more aspects of risk factors, but has drawbacks as well. Improper application of methods might result in biased exposure estimates, which has serious consequences for risk estimates arising from epidemiological studies. The aim of this paper was to systematically evaluate the usefulness of different measurement methods in terms of accuracy and applicability. Assessment of external exposure measures by subjective judgements (from experts or self reports from workers), observational methods (on site or afterwards from video recordings), and direct measurements methods (at work or during laboratory simulations) are discussed for each of the dimensions of exposure level, duration, and frequency. It is concluded that expert judgements and self reports give only limited insight into the occurrence of tasks and activities. Further information can be obtained from observations, which can best be combined with direct measurements of exposure to posture, movement, and exerted forces to achieve exposure profiles by occupational task. Internal exposures estimated by biomechanical modelling mostly consider the low back and require information on postures of the different body segments and exerted forces, completed with movement data in the case of dynamic models. Moreover, electromyography (EMG) and measurements of intra-abdominal pressure might be used for this purpose. Both biomechanical models and EMG are useful methods to assess internal exposure, but biomechanical models should not be restricted to the level of compressive forces on the lower back. Finally, current problems and future directions in measurement strategies and methods are discussed.   PMID:9764106

  15. Mitochondrial DNA and Cancer Epidemiology Workshop

    Cancer.gov

    A workshop to review the state-of-the science in the mitochondrial DNA field and its use in cancer epidemiology, and to develop a concept for a research initiative on mitochondrial DNA and cancer epidemiology.

  16. About the Epidemiology and Genomics Research Program

    Cancer.gov

    Epidemiology is the scientific study of the causes and distribution of disease in populations. NCI-funded epidemiology research is conducted through research at institutions in the United States and internationally.

  17. Glossary for econometrics and epidemiology.

    PubMed

    Gunasekara, F Imlach; Carter, K; Blakely, T

    2008-10-01

    Epidemiologists and econometricians are often interested in similar topics-socioeconomic position and health outcomes-but the different languages that epidemiologists and economists use to interpret and discuss their results can create a barrier to mutual communication. This glossary defines key terms used in econometrics and epidemiology to assist in bridging this gap.

  18. Brain Tumor Epidemiology Consortium (BTEC)

    Cancer.gov

    The Brain Tumor Epidemiology Consortium is an open scientific forum organized to foster the development of multi-center, international and inter-disciplinary collaborations that will lead to a better understanding of the etiology, outcomes, and prevention of brain tumors.

  19. Methodologic research needs in environmental epidemiology: data analysis.

    PubMed Central

    Prentice, R L; Thomas, D

    1993-01-01

    A brief review is given of data analysis methods for the identification and quantification of associations between environmental exposures and health events of interest. Data analysis methods are outlined for each of the study designs mentioned, with an emphasis on topics in need of further research. Particularly noted are the need for improved methods for accommodating exposure assessment measurement errors in analytic epidemiologic studies and for improved methods for the conduct and analysis of aggregate data (ecologic) studies. PMID:8206041

  20. Conduct Disorder and Oppositional Defiant Disorder in a National Sample: Developmental Epidemiology

    ERIC Educational Resources Information Center

    Maughan, Barbara; Rowe, Richard; Messer, Julie; Goodman, Robert; Meltzer, Howard

    2004-01-01

    Background: Despite an expanding epidemiological evidence base, uncertainties remain over key aspects of the epidemiology of the "antisocial" disorders in childhood and adolescence. Methods: We used cross-sectional data on a nationally representative sample of 10,438 5-15-year-olds drawn from the 1999 British Child Mental Health Survey…

  1. Epidemiology of hepatitis C virus exposure in Egypt: Opportunities for prevention and evaluation

    PubMed Central

    Miller, F DeWolfe; Elzalabany, Mahmoud S; Hassani, Sara; Cuadros, Diego F

    2015-01-01

    AIM: To critically evaluate the current epidemiology data on exposures, rather than infection, to hepatitis C virus (HCV) transmission and recommend epidemiologic strategies to fill gaps. METHODS: Standard methods for identifying and evaluating relevant epidemiologic literature and available data were used. RESULTS: There is a large body of literature on the epidemiology of HCV transmission in Egypt that collectively identifies ongoing iatrogenic exposures as the major driver for HCV transmission due to short comings in infection control and standard procedures. Additional epidemiologic studies on HCV transmission that requires the participation of human subject is unwarranted. Alternatively, very little literature was found on the epidemiology of exposure to HCV, infection control, and safe injection practices. The information that is available on patterns of HCV exposure shows high frequencies of inadequate infection control, problems in sterilization in health care facilities, low rates of hand washing, untrained personnel, lack of stated policies in facilities, HCV contamination of instruments and very large injection frequencies with low but very significant syringe and needle reuse. There is an important need to increase the number, size, and diversity of epidemiologic studies on HCV exposures, patterns of risk factors for infection, infection control, and safe injection practices. In addition to health care facilities evaluation, relevant knowledge attitude and practice studies are recommended. CONCLUSION: Epidemiologic methods on HCV exposure can be used to characterize the magnitude of exposures to HCV infection, target interventions to reduce exposures, and provide the best method for evaluating interventions by demonstrating the reduction of exposure to HCV infection. PMID:26668697

  2. Relative risk regression analysis of epidemiologic data.

    PubMed

    Prentice, R L

    1985-11-01

    Relative risk regression methods are described. These methods provide a unified approach to a range of data analysis problems in environmental risk assessment and in the study of disease risk factors more generally. Relative risk regression methods are most readily viewed as an outgrowth of Cox's regression and life model. They can also be viewed as a regression generalization of more classical epidemiologic procedures, such as that due to Mantel and Haenszel. In the context of an epidemiologic cohort study, relative risk regression methods extend conventional survival data methods and binary response (e.g., logistic) regression models by taking explicit account of the time to disease occurrence while allowing arbitrary baseline disease rates, general censorship, and time-varying risk factors. This latter feature is particularly relevant to many environmental risk assessment problems wherein one wishes to relate disease rates at a particular point in time to aspects of a preceding risk factor history. Relative risk regression methods also adapt readily to time-matched case-control studies and to certain less standard designs. The uses of relative risk regression methods are illustrated and the state of development of these procedures is discussed. It is argued that asymptotic partial likelihood estimation techniques are now well developed in the important special case in which the disease rates of interest have interpretations as counting process intensity functions. Estimation of relative risks processes corresponding to disease rates falling outside this class has, however, received limited attention. The general area of relative risk regression model criticism has, as yet, not been thoroughly studied, though a number of statistical groups are studying such features as tests of fit, residuals, diagnostics and graphical procedures. Most such studies have been restricted to exponential form relative risks as have simulation studies of relative risk estimation

  3. Cancer Epidemiology Matters Blog - 2012 Archive

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  4. Cancer Epidemiology Matters Blog - 2013 Archive

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  5. Cancer Epidemiology Matters Blog - 2014 Archive

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  6. Cancer Epidemiology Matters Blog - 2015 Archive

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  7. Seasonal Variation in Epidemiology

    ERIC Educational Resources Information Center

    Marrero, Osvaldo

    2013-01-01

    Seasonality analyses are important in medical research. If the incidence of a disease shows a seasonal pattern, then an environmental factor must be considered in its etiology. We discuss a method for the simultaneous analysis of seasonal variation in multiple groups. The nuts and bolts are explained using simple trigonometry, an elementary…

  8. Combining Epidemiologic Information Across Space Agencies

    NASA Technical Reports Server (NTRS)

    Minard, Charles G.; Clark, April L.; Wear, Mary L.; Mason, Sara; Van Baalen, Mary

    2010-01-01

    Space flight is a very unique occupational exposure with potential hazards that are not fully understood. A limited number of individuals have experienced the exposures incurred during space flight, and epidemiologic research would benefit from shared information across space agencies. However, data sharing can be problematic due to agency protection policies for personally identifiable information as well as medical records. Compliance with these protocols in the astronaut population is particularly difficult given the small, high-profile population under study. Creativity in combining data is necessary in order to overcome these difficulties and improve statistical power in research. This study presents methods in meta-analysis that may be used to combine non-attributable data across space agencies so that meaningful conclusions may be drawn about study interests. Methods for combining epidemiologic data across space agencies are presented, and the processes are demonstrated using life-time mortality data in U.S. astronauts and Russian cosmonauts. This proof of concept was found to be an acceptable way of sharing data across agencies, and will be used in the future as more relevant research interests are identified.

  9. The global epidemiology of waterpipe smoking

    PubMed Central

    Maziak, Wasim; Taleb, Ziyad Ben; Bahelah, Raed; Islam, Farahnaz; Jaber, Rana; Auf, Rehab; Salloum, Ramzi G

    2015-01-01

    Objectives In the past decade, waterpipe smoking (a.k.a. hookah, shisha, narghile) has become a global phenomenon. In this review, we provide an updated picture of the main epidemiological trends in waterpipe smoking globally. Data sources Peer-reviewed publications indexed in major biomedical databases between 2004 and 2014. Search keywords included a combination of: waterpipe, hookah, shisha along with epidemiology, patterns, prevalence and predictors. We also used different spellings of waterpipe terms commonly used. Study selection The focus was on studies with large representative samples, national data or high-quality reports that illuminated aspects of the epidemiology and trends in waterpipe smoking. Data extraction Multiple researchers extracted the data independently and collectively decided on the most important and pertinent studies to include in the review. Data synthesis Waterpipe smoking has become a global phenomenon among youth. The global waterpipe epidemic is likely driven by (1) the introduction of manufactured flavoured tobacco (Maassel); (2) the intersection between waterpipe's social dimension and thriving café culture; (3) the evolution of mass communication media; (4) the lack of regulatory/policy framework specific to the waterpipe. Waterpipe smoking is becoming the most popular tobacco use method among youth in the Middle East, and is quickly gaining popularity elsewhere. Important patterns of waterpipe smoking include the predominance among younger, male, high socioeconomic, and urban groups. Intermittent and social use are also noted patterns. Conclusions Waterpipe smoking has become a global public health problem. Developing surveillance, intervention and regulatory/policy frameworks specific to the waterpipe has become a public health priority. PMID:25298368

  10. Injury epidemiology in Iran: a systematic review

    PubMed Central

    Azami-Aghdash, Saber; Sadeghi-Bazargani, Homayoun; Shabaninejad, Hosein; Abolghasem Gorji, Hassan

    2017-01-01

    Abstract: Background: Injuries are the second greatest cause of mortality in Iran. Information about the epidemiological pattern of injuries is effective in decision-making. In this regard, the aim of the current study is to elaborate on the epidemiology of injuries in Iran through a systematic review. Methods: Required data were collected searching the following key words and their Persian equivalents; trauma, injury, accident, epidemiology, prevalence, pattern, etiology, risk factors and Iran. The following databases were searched: Google Scholar, PubMed, Scopus, MagIran, Iranian scientific information database (SID) and Iran Medex. Some of the relevant journals and web sites were searched manually. The lists of references from the selected articles were also investigated. We have also searched the gray literature and consulted some experts. Results: Out of 2747 retrieved articles, 25 articles were finally included in the review. A total of 3234481 cases have been investigated. Mean (SD) age among these cases was 30 (17.4) years. The males comprised 75.7% of all the patients. Only 31.1% of patients were transferred to hospital by ambulance. The most common mechanism of injuries was road traffic accidents (50.1%) followed by falls (22.3%). In road traffic accidents, motorcyclists have accounted for the majority of victims (45%). Roads were the most common accident scene for the injuries (57.5%). The most common injuries were to the head and neck. (47.3%). The mean (SD) Injury Severity Score (ISS) was 8.1(8.6%). The overall case-fatality proportion was 3.8% and 75% of all the mortalities related to road traffic accidents. Conclusions: The main priorities in reducing the burden of injuries include: the young, male target group, improving pre-hospital and ambulance services, preventing road traffic accidents, improving road safety and the safety of motorcyclists (compulsory helmet use, safer vehicles, dedicated motorcycle lanes). PMID:28039683

  11. Improving Concordance in Environmental Epidemiology: A Three-Part Proposal

    PubMed Central

    LaKind, Judy S.; Goodman, Michael; Makris, Susan L.; Mattison, Donald R.

    2015-01-01

    In observational research, evidence is usually derived from multiple studies, and any single result is rarely considered sufficient for public health decision making. Despite more than five decades of research and thousands of studies published, the ability to draw robust conclusions regarding the presence or absence of causal links between specific environmental exposures and human health remains limited. To develop policies that are protective of public health and can withstand scrutiny, agencies need to rely on investigations of satisfactory quality that follow sufficiently concordant protocols in terms of exposure assessment, outcome ascertainment, data analysis, and reporting of results. Absent such concordance, the ability of environmental epidemiology studies to inform decision making is greatly diminished. Systems and tools are proposed here to improve concordance among environmental epidemiology studies. Specifically, working systems in place in other fields of research are critically examined and used as guidelines to develop analogous policies and procedures for environmental epidemiology. A three-part path forward toward more concordant, transparent, and readily accessible environmental epidemiology evidence that parallels ongoing efforts in medical research is proposed. The three parts address methods for improving quality and accessibility of systematic reviews, access to information on ongoing and completed studies, and principles for reporting. The goals are to increase the value of epidemiological research in public health decision making and to stimulate discussions around solutions proposed herein. PMID:26158301

  12. Childhood Brain Tumor Epidemiology: A Brain Tumor Epidemiology Consortium Review

    PubMed Central

    Johnson, Kimberly J.; Cullen, Jennifer; Barnholtz-Sloan, Jill S.; Ostrom, Quinn T.; Langer, Chelsea E.; Turner, Michelle C.; McKean-Cowdin, Roberta; Fisher, James L.; Lupo, Philip J.; Partap, Sonia; Schwartzbaum, Judith A.; Scheurer, Michael E.

    2014-01-01

    Childhood brain tumors are the most common pediatric solid tumor and include several histological subtypes. Although progress has been made in improving survival rates for some subtypes, understanding of risk factors for childhood brain tumors remains limited to a few genetic syndromes and ionizing radiation to the head and neck. In this report, we review descriptive and analytical epidemiology childhood brain tumor studies from the past decade and highlight priority areas for future epidemiology investigations and methodological work that is needed to advance our understanding of childhood brain tumor causes. Specifically, we summarize the results of a review of studies published since 2004 that have analyzed incidence and survival in different international regions and that have examined potential genetic, immune system, developmental and birth characteristics, and environmental risk factors. PMID:25192704

  13. Epidemiology of chronic non-specific respiratory diseases*

    PubMed Central

    1975-01-01

    The current state of research into the epidemiology of chronic non-specific respiratory diseases (CNSRD) is reviewed. Recommendations are made on the definitions of CNSRD for use in epidemiological studies, and various aspects of the etiology and natural history of CNSRD are identified as requiring further investigation. The need for standardization of investigative methods is emphasized. Since smoking is such an important factor in the etiology of CNSRD, it is recommended that efforts be made to discourage children from taking up the habit. PMID:1084795

  14. An Application of Epidemiological Modeling to Information Diffusion

    NASA Astrophysics Data System (ADS)

    McCormack, Robert; Salter, William

    Messages often spread within a population through unofficial - particularly web-based - media. Such ideas have been termed "memes." To impede the flow of terrorist messages and to promote counter messages within a population, intelligence analysts must understand how messages spread. We used statistical language processing technologies to operationalize "memes" as latent topics in electronic text and applied epidemiological techniques to describe and analyze patterns of message propagation. We developed our methods and applied them to English-language newspapers and blogs in the Arab world. We found that a relatively simple epidemiological model can reproduce some dynamics of observed empirical relationships.

  15. Strengthening the Reporting of Observational Studies in Epidemiology—Nutritional Epidemiology (STROBE-nut): An Extension of the STROBE Statement

    PubMed Central

    Hawwash, Dana; Ocké, Marga C.; Berg, Christina; Forsum, Elisabet; Sonestedt, Emily; Wirfält, Elisabet; Åkesson, Agneta; Kolsteren, Patrick; Byrnes, Graham; De Keyzer, Willem; Van Camp, John; Slimani, Nadia; Cevallos, Myriam; Egger, Matthias; Huybrechts, Inge

    2016-01-01

    Background Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology—Nutritional Epidemiology (STROBE-nut). Methods and Findings Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, coordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three-round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. Conclusion When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health. PMID:27270749

  16. Brain Tumor Epidemiology: Consensus from the Brain Tumor Epidemiology Consortium (BTEC)

    PubMed Central

    Bondy, Melissa L.; Scheurer, Michael E.; Malmer, Beatrice; Barnholtz-Sloan, Jill S.; Davis, Faith G.; Il’yasova, Dora; Kruchko, Carol; McCarthy, Bridget J.; Rajaraman, Preetha; Schwartzbaum, Judith A.; Sadetzki, Siegal; Schlehofer, Brigitte; Tihan, Tarik; Wiemels, Joseph L.; Wrensch, Margaret; Buffler, Patricia A.

    2010-01-01

    Epidemiologists in the Brain Tumor Epidemiology Consortium (BTEC) have prioritized areas for further research. Although many risk factors have been examined over the past several decades, there are few consistent findings possibly due to small sample sizes in individual studies and differences between studies in subjects, tumor types, and methods of classification. Individual studies have generally lacked sufficient sample size to examine interactions. A major priority based on available evidence and technologies includes expanding research in genetics and molecular epidemiology of brain tumors. BTEC has taken an active role in promoting understudied groups such as pediatric brain tumors, the etiology of rare glioma subtypes, such as oligodendroglioma, and meningioma, which not uncommon, has only recently been systematically registered in the US. There is also a pressing need to bring more researchers, especially junior investigators, to study brain tumor epidemiology. However, relatively poor funding for brain tumor research has made it difficult to encourage careers in this area. We review the group’s consensus on the current state of scientific findings and present a consensus on research priorities to identify the important areas the science should move to address. PMID:18798534

  17. Molecular epidemiology of tuberculosis: achievements and challenges to current knowledge.

    PubMed Central

    Murray, Megan; Nardell, Edward

    2002-01-01

    Over the past 10 years, molecular methods have become available with which to strain-type Mycobacterium tuberculosis. They have allowed researchers to study certain important but previously unresolved issues in the epidemiology of tuberculosis (TB). For example, some unsuspected microepidemics have been revealed and it has been shown that the relative contribution of recently acquired disease to the TB burden in many settings is far greater than had been thought. These findings have led to the strengthening of TB control. Other research has demonstrated the existence and described the frequency of exogenous reinfection in areas of high incidence. Much recent work has focused on the phenotypic variation among strains and has evaluated the relative transmissibility, virulence, and immunogenicity of different lineages of the organism. We summarize the recent achievements in TB epidemiology associated with the introduction of DNA fingerprinting techniques, and consider the implications of this technology for the design and analysis of epidemiological studies. PMID:12132006

  18. Epidemiological criminology: drug use among African American gang members.

    PubMed

    Lanier, Mark M; Pack, Robert P; Akers, Timothy A

    2010-01-01

    Epidemiological methods and public health theories can be tied to theories of crime and delinquency and used to create evidence-based policy. Interdisciplinary theoretical approaches to existing, and emerging, public health and criminal justice problems hold great promise. Differential association theory postulates that close association with delinquent peers leads to an increase in deviant activities such as illicit drug use. Social cognitive theory postulates that health behavior change is driven by the interaction of (a) cognitive states that support a health outcome, (b) the social and contextual environment, (c) and individual action. Combined, these theories can be applied to drug eradication programs as well as other health and crime issues. Focus groups and interviews were performed to identify rates of illicit substance use among incarcerated African American adolescent male gang members and nongang members. The policy recommendations illustrate the convergence of criminological and epidemiological theory under the new paradigm of epidemiological criminology or ''EpiCrim.''

  19. Epidemiology of Hospital-Treated Injuries Sustained by Fitness Participants

    ERIC Educational Resources Information Center

    Gray, Shannon E.; Finch, Caroline F.

    2015-01-01

    Purpose: The purpose of this study was to provide an epidemiological profile of injuries sustained by participants in fitness activities in Victoria, Australia, based on hospital admissions and emergency department (ED) presentations and to identify the most common types, causes, and sites of these injuries. Method: Hospital-treated fitness…

  20. [Epidemiological research on environmental health risks and their economic consequences].

    PubMed

    Haucke, F; Holle, R; Wichmann, H E

    2009-12-01

    In environmental health research, methods for quantitative analysis of human population studies data are gaining importance. In recent years, it has been realized that they can also provide an important link to the economic view on environmental health effects. In this review, fundamental concepts and methods from environmental epidemiology and health economics are presented and it is shown how they can be linked in order to support environmental policy decisions. In addition, the characteristics of environmental epidemiology and the role of epidemiologic studies in risk assessment are discussed. From the economic point of view, cost-of-illness studies and cost effectiveness studies are the main approaches, and we have placed special focus on methods of monetary valuation of health effects that are generally proposed in the environmental context. Two conceptually differing strategies to combine epidemiologic and economic evidence are presented: the environmental attributable fraction model as a top-down approach and the impact pathway approach which follows a bottom-up analysis strategy. Finally, two examples are used to illustrate the application of these concepts and methods: health risks caused by fine particle air pollution and their costs, and the cost-effectiveness of radon exposure reduction policies.

  1. [A conceptual and operational framework for an epidemiology of citizenship].

    PubMed

    Tognoni, Gianni

    2010-01-01

    "Epidemiology of citizenship" is the challenge of a multidisciplinary group of clinicians, epidemiologists, social workers that, with this book, try to approach problems implementing a cross-fertilization of methods, approach, languages and interventions across the different disciplines. The introduction of the book is proposed where its background and philosophy are presented and discussed.

  2. [Studies on markers of exposure and early effect in areas with arsenic pollution: methods and results of the project SEpiAs. Epidemiological studies on population exposed to low-to-moderate arsenic concentration in drinking water].

    PubMed

    Bustaffa, Elisa; Bianchi, Fabrizio

    2014-01-01

    Arsenic and its inorganic compounds are classified as human carcinogens. Several epidemiological studies conducted in areas of the world characterized by high arsenic concentration in drinking water, even up to 3,000 μg/l, report associations between arsenic exposure and skin, bladder, lung, liver and kidney cancer as well as cardiovascular diseases, diabetes and reproductive and developmental effects. Since general population is not exposed to these high arsenic concentrations in the last years attention focused on adverse health effects that low-to-moderate arsenic concentrations (0-150 μg/l) in drinking water could induce. The World Health Organization recommends a maximum limit of 10 μg/l for arsenic in drinking water. Almost all epidemiological studies conducted on populations exposed to low-to-moderate arsenic concentrations in drinking water are limited due to problems arising from both individual exposure assessment and low subjects number. The aim of the present review is to collect literature-based evidences regarding adverse health effects associated with exposure to low-to-moderate arsenic concentrations in drinking water (10-150 μg/l) in order to obtain a comprehensive picture of the health outcomes that such exposure can have on general population.

  3. [Epidemiology of Asperger's syndrome].

    PubMed

    Suzuki, Yukiko; Saito, Kazuhiko

    2007-03-01

    Only a little data is available so far on the prevalence of Asperger's syndrome. The prevalence that Fombonne (2003) estimated after considering six European research was 2/10,000. In Ishikawa's study (2006) conducted in Nagoya city, Japan, the prevalence of Asperger's syndrome was 56/10,000. Currently there are not strict diagnostic criteria of Asperger's syndrome and methods of investigation are not consistent in each study. Therefore the prevalence rate for Asperger's syndrome covered very wide range. Although we still don't have a precise prevalence data on Asperger's syndrome, the awareness of this syndrome emerged in these several decades tells us that further research and support for the children of Asperger's syndrome and their family are necessary.

  4. Epidemiology of human listeriosis.

    PubMed Central

    Schuchat, A; Swaminathan, B; Broome, C V

    1991-01-01

    During the 1980s, investigation of several large epidemics of listeriosis confirmed that transmission of L. monocytogenes in food causes human disease. Progress in laboratory detection and subtyping of the organism has enhanced our ability to compare human and environmental isolates of L. monocytogenes. Transmission by foodborne organisms is now recognized as causing both epidemic and sporadic listeriosis. Continued study of dietary risk factors associated with listeriosis is needed in order to develop dietary recommendations for the expanding population at increased risk of disease. Current research application of new molecular methods to the study of L. monocytogenes may improve the ability to diagnose pregnancy-associated disease and permit the rapid detection and control of L. monocytogenes in the food supply. PMID:1906370

  5. Is epidemiology correcting its vision problem? A perspective on our perspective: 2012 presidential address for American College of Epidemiology.

    PubMed

    McKeown, Robert E

    2013-10-01

    Epidemiology, like all disciplines, exists within and is shaped by a culture that frames its ways of understanding. In the last 60 years epidemiology as a discipline and scientific approach has undergone major transition, but remains challenged by vestiges of the limiting frameworks of our origins which shape the way we approach questions, and even the questions we choose to investigate. A part of the current transformation is a reframing of our perspective and a broadening of our methods to encourage creativity and to encompass new types of evidence and new approaches to investigation and interpretation. Epidemiologists are developing innovative ways to approach increasingly complex problems and becoming more open to multi-disciplinary approaches to solving epidemiologic challenges.

  6. [Epidemiology of HTN in dialysis].

    PubMed

    Simon, P

    2007-10-01

    Increased cardio-vascular morbidity-mortality in dialysed patients is particularly due to an insufficiency of blood pressure control. Previous epidemiological surveys show that prevalence of dialysis hypertension is high, from 55 to 85% according to period and mean age of the studied population, despite an improvement of dialysis strategies during the last decade. Control of hypertension is not better in peritoneal dialysis than in haemodialysis. Antihypertensive drugs are administered to 3/4 of dialysed patients. Dialysis strategies which increase the number of sessions per week or the duration of each session in conventional haemodialysis improve the volume control and consequently the blood pressure. Atherosclerosis, cause or consequence of hypertension in dialysed elderly patients, more and more old, lead to adapt treatment strategies in order to prevent hypotension, which is also, a major risk factor of morbidity-mortality in dialysed patients (reverse epidemiology).

  7. Epidemiology of idiopathic pulmonary fibrosis

    PubMed Central

    Ley, Brett; Collard, Harold R

    2013-01-01

    Idiopathic pulmonary fibrosis is a chronic fibrotic lung disease of unknown cause that occurs in adults and has a poor prognosis. Its epidemiology has been difficult to study because of its rarity and evolution in diagnostic and coding practices. Though uncommon, it is likely underappreciated both in terms of its occurrence (ie, incidence, prevalence) and public health impact (ie, health care costs and resource utilization). Incidence and mortality appear to be on the rise, and prevalence is expected to increase with the aging population. Potential risk factors include occupational and environmental exposures, tobacco smoking, gastroesophageal reflux, and genetic factors. An accurate understanding of its epidemiology is important, especially as novel therapies are emerging. PMID:24348069

  8. Molecular Epidemiology for Vector Research on Leishmaniasis

    PubMed Central

    Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Uezato, Hiroshi; Mimori, Tatsuyuki; Hashiguchi, Yoshihisa

    2010-01-01

    Leishmaniasis is a protozoan disease caused by the genus Leishmania transmitted by female phlebotomine sand flies. Surveillance of the prevalence of Leishmania and responsive vector species in endemic and surrounding areas is important for predicting the risk and expansion of the disease. Molecular biological methods are now widely applied to epidemiological studies of infectious diseases including leishmaniasis. These techniques are used to detect natural infections of sand fly vectors with Leishmania protozoa and are becoming powerful tools due to their sensitivity and specificity. Recently, genetic analyses have been performed on sand fly species and genotyping using PCR-RFLP has been applied to the sand fly taxonomy. In addition, a molecular mass screening method has been established that enables both sand fly species and natural leishmanial infections to be identified simultaneously in hundreds of sand flies with limited effort. This paper reviews recent advances in the study of sand flies, vectors of leishmaniasis, using molecular biological approaches. PMID:20617005

  9. [Epidemiology of burns in France].

    PubMed

    Latarjet, Jacques; Ravat, François

    2012-01-01

    As with most traumas, the epidemiology of the "burn" health-event has long been neglected by public health doctors and rarely considered by burns specialists. There were therefore few verified data and many approximations and preconceived ideas. The gathering of information recently undertaken in France enables the reliability of the data to be improved and the diagnostic and demographic elements relating to hospitalised patients with burns to be established.

  10. Current Epidemiology of Genitourinary Trauma

    PubMed Central

    McGeady, James B.; Breyer, Benjamin N.

    2013-01-01

    Synopsis This article reviews recent publications evaluating the current epidemiology of urologic trauma. It begins by providing a brief explanation of databases that have been recently used to study this patient population, then proceeds to discuss each genitourinary organ individually, discussing the most relevant and up to date information published for each one. The conclusion of the article briefly discusses possible future research and development areas pertaining to the topic. PMID:23905930

  11. Current practices in teaching introductory epidemiology: how we got here, where to go.

    PubMed

    Keyes, Katherine M; Galea, Sandro

    2014-10-01

    The number of students and disciplines requiring basic instruction in epidemiologic methods is growing. As a field, we now have a lexicon of epidemiologic terminology and particular methods that have developed and become canonical through the historical development of the field. Yet, many of our basic concepts remain elusive to some students, particularly those not pursuing a career in epidemiology. Further, disagreement and redundancy across basic terms limit their utility in teaching epidemiology. Many approaches to teaching epidemiology generally start with labeling key concepts and then move on to explain them. We submit that an approach grounded not in labels but in foundational concepts may offer a useful adjunct to introductory epidemiology education. We propose 7 foundational steps in conducting an epidemiologic study and provide examples of how these steps can be operationalized, using simple graphics that articulate how populations are defined, samples are selected, and individuals are followed to count cases. A reorganization of introductory epidemiology around core first principles may be an effective way forward for educating the next generation of public health scientists.

  12. Onychomycosis in Israel: epidemiological aspects.

    PubMed

    Segal, Rina; Shemer, Avner; Hochberg, Malca; Keness, Yoram; Shvarzman, Rima; Mandelblat, Marina; Frenkel, Michael; Segal, Esther

    2015-03-01

    Onychomycosis is a fungal infection treated orally for prolonged periods of treatment, caused primarily by Dermatophytes, Candida species and non-dermatophyte moulds (NDMs). The prevalence of specific aetiology may differ in dependence of environmental, geographic and demographic factors, and may affect management of the infection. The objective of this survey was to analyse epidemiologic parameters of onychomycosis in Israel. Data of a cohort of 27,093 patients were collected from six centres during a 2- and 10-year period. The diagnosis was based on microscopy of KOH/calcofluor mounts of nail scrapings and culture isolation. A positive result indicates isolation of a fungus in culture. Data were analysed for each centre and expressed as range for the whole cohort, using the spss v18 software. Analysis included three epidemiologic parameters: fungal aetiology in toe- and fingernails; association with gender; association with age group. Dermatophytes were the major causative agents and Trichophyton rubrum the most frequent isolate. Candida species were more frequent in women fingernails; frequency increased with age and C. parapsilosis the most frequent species. NDMs were isolated at low rate and Aspergillus terreus was the most frequent isolate. This is a first large cohort of onychomycosis patients from Israel analysed by defined epidemiological parameters.

  13. Natural history of tuberculosis. Epidemiology.

    PubMed

    Grzybowski, S

    1991-12-01

    This Symposium honours the achievements of Dr Karel Styblo. In this presentation, specific epidemiologic insights are reviewed. Studies of the epidemiology of tuberculosis in Eskimos showed a picture of tuberculosis at the height of the epidemic. Very high incidence was observed in young people who experienced a high fatality rate. Application of specific control measures were accompanied by rapid decline in rates, greater than observed in any other human population, demonstrating that tuberculosis could be brought under control by specific intervention. Studies of the natural trend of tuberculosis in South India showed that, even in the absence of intervention, a decline was observed in the rates of this disease. In the absence of chemotherapy, 50 per cent of cases die within 5 years, 30 per cent recover spontaneously and 20 per cent remain sputum positive. Studies of the efficacy of BCG in Madras, enabled to study the impact of efficient case-finding associated with poor treatment results showing that such a situation multiplies the number of surviving, infectious cases in the community and, thus, actually deteriorates the epidemiological situation. These various basic studies have shown both how to create success and how to create failure in tuberculosis programmes.

  14. Epidemiology and clinical presentations of the four human coronaviruses 229E, HKU1, NL63, and OC43 detected over 3 years using a novel multiplex real-time PCR method.

    PubMed

    Gaunt, E R; Hardie, A; Claas, E C J; Simmonds, P; Templeton, K E

    2010-08-01

    Four human coronaviruses (HCoV-229E, HCoV-HKU1, HCoV-NL63, and HCoV-OC43) are associated with a range of respiratory outcomes, including bronchiolitis and pneumonia. Their epidemiologies and clinical characteristics are poorly described and are often reliant on case reports. To address these problems, we conducted a large-scale comprehensive screening for all four coronaviruses by analysis of 11,661 diagnostic respiratory samples collected in Edinburgh, United Kingdom, over 3 years between July 2006 and June 2009 using a novel four-way multiplex real-time reverse transcription-PCR (RT-PCR) assay. Coronaviruses were detected in 0.3 to 0.85% of samples in all age groups. Generally, coronaviruses displayed marked winter seasonality between the months of December and April and were not detected in summer months, which is comparable to the pattern seen with influenza viruses. HCoV-229E was the exception; detection was confined to the winter of 2008 and was sporadic in the following year. There were additional longer-term differences in detection frequencies between seasons, with HCoV-OC43 predominant in the first and third seasons and HCoV-HKU1 dominating in the second (see Results for definitions of seasons). A total of 11 to 41% of coronaviruses detected were in samples testing positive for other respiratory viruses, although clinical presentations of coronavirus monoinfections were comparable to those of viruses which have an established role in respiratory disease, such as respiratory syncytial virus, influenza virus, and parainfluenza viruses. The novel multiplex assay for real-time pan-coronavirus detection enhances respiratory virus diagnosis, overcomes potential diagnostic problems arising through seasonal variation in coronavirus frequency, and provides novel insights into the epidemiology and clinical implications of coronaviruses.

  15. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1982-08-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.

  16. Epidemiology of bovine viral diarrhea virus.

    PubMed

    Houe, H

    1995-11-01

    Prevalence studies around the world show that BVDV is widespread in most cattle raising countries. There are significant differences, however, in prevalence between areas, probably the result of differences in cattle population structure and management practice. Direct contact with PI animals is probably the most important method of transmission of infection; however, field studies have shown that some limited spread of infection also occurs in the absence of PI animals. This may be due to contact with acutely infected animals or contact with other species infected with BVDV. Different ways of indirect transmission such as contaminated needles and equipment have been proven experimentally, and indirect transmission is considered to have some importance. If a PI animal is introduced directly into a dairy herd, most animals will be infected within a few months. On many occasions, however, a herd gets infected by other means than direct introduction of PI animals. In these cases, the infection is often spread to only a few animals after which the infections stops. The infection is then reinforced when PI animals are born. Slow and hence prolonged spread of infection in herds without PI animals also has been described, but the mechanism is not fully understood. Family lines of PI animals delivering PI calves are fairly common and can cause the infection to continue for several years. The clinical manifestations, acute BVDV, reproductive disorders, birth of malformed, weak and undersized calves, unthrifty PI animals, and mucosal disease often appear within certain periods. Large variation, however, can occur between herd outbreaks due to variation in virulence of the BVDV strain, housing of the cattle, and variation in transmission patterns. The extensive transmission of infection from PI animals makes different surveillance methods possible. Thus testing of a screening sample of a few young stock of antibodies and determination of antibody titer in bulk milk will often

  17. Epidemiology of and diagnostic strategies for toxoplasmosis.

    PubMed

    Robert-Gangneux, Florence; Dardé, Marie-Laure

    2012-04-01

    The apicomplexan parasite Toxoplasma gondii was discovered a little over 100 years ago, but knowledge of its biological life cycle and its medical importance has grown in the last 40 years. This obligate intracellular parasite was identified early as a pathogen responsible for congenital infection, but its clinical expression and the importance of reactivations of infections in immunocompromised patients were recognized later, in the era of organ transplantation and HIV infection. Recent knowledge of host cell-parasite interactions and of parasite virulence has brought new insights into the comprehension of the pathophysiology of infection. In this review, we focus on epidemiological and diagnostic aspects, putting them in perspective with current knowledge of parasite genotypes. In particular, we provide critical information on diagnostic methods according to the patient's background and discuss the implementation of screening tools for congenital toxoplasmosis according to health policies.

  18. The genetic epidemiology of personality disorders

    PubMed Central

    Reichborn-Kjennerud, Ted

    2010-01-01

    Genetic epidemiologic studies indicate that all ten personality disorders (PDs) classified on the DSM-IV axis II are modestly to moderately heritable. Shared environmental and nonadditive genetic factors are of minor or no importance. No sex differences have been identified. Multivariate studies suggest that the extensive comorbidity between the PDs can be explained by three common genetic and environmental risk factors. The genetic factors do not reflect the DSM-IV cluster structure, but rather: i) broad vulnerability to PD pathology or negative emotionality; ii) high impulsivity/low agreeableness; and iii) introversion. Common genetic and environmental liability factors contribute to comorbidity between pairs or clusters of axis I and axis II disorders. Molecular genetic studies of PDs, mostly candidate gene association studies, indicate that genes linked to neurotransmitter pathways, especially in the serotonergic and dopaminergic systems, are involved. Future studies, using newer methods like genome-wide association, might take advantage of the use of endophenotypes. PMID:20373672

  19. Molecular epidemiology of Legionella pneumophila serogroup 1.

    PubMed Central

    van Ketel, R J; ter Schegget, J; Zanen, H C

    1984-01-01

    The DNA of patient and environmental isolates of Legionella pneumophila serogroup 1 was analyzed by restriction endonuclease cleavage. The electrophoretic patterns of the DNA digests of isolates from a group of patients with Legionnaires disease acquired in a hospital were indistinguishable from one another and were identical to the DNA pattern of a strain isolated from the hot water supply of the hospital. On the other hand, they were easily differentiated from strains isolated from patients and hot water supplies in other hospitals in the same city. The homogeneity of populations of L. pneumophila serogroup 1 colonizing plumbing systems was also investigated by DNA restriction endonuclease analysis in three hospitals. We distinguished two subtypes in one hospital; the two other hospitals had homogeneous populations. Restriction endonuclease digest analysis of L. pneumophila serogroup 1 DNA enables subtyping and appears to be a useful method for examining the epidemiology of outbreaks of Legionnaires disease. Images PMID:6092423

  20. Evaluation of endometrial cancer epidemiology in Romania.

    PubMed

    Bohîlțea, R E; Furtunescu, F; Dosius, M; Cîrstoiu, M; Radoi, V; Baroș, A; Bohîlțea, L C

    2015-01-01

    Endometrial cancer represents the most frequent gynecological malignant affection in the developed countries, in which the incidence of cervical cancer has significantly decreased due to the rigorous application of screening methods and prophylaxis. According to its frequency, endometrial cancer is situated on the fourth place in the category of women's genital-mammary malignant diseases, after breast, cervical and ovarian cancer in Romania. The incidence and mortality rates due to endometrial cancer have registered an increasing trend worldwide and also in Romania, a significant decrease of the age of appearance for the entire endometrial pathology sphere being noticed. At the national level, the maximum incidence is situated between 60 and 64 years old, the mortality rate of the women under 65 years old being high in Romania. The study evaluates endometrial cancer, from an epidemiologic point of view, at the national level compared to the international statistic data.

  1. The genetic epidemiology of personality disorders.

    PubMed

    Reichborn-Kjennerud, Ted

    2010-01-01

    Genetic epidemiologic studies indicate that all ten personality disorders (PDs) classified on the DSM-IV axis II are modestly to moderately heritable. Shared environmental and nonadditive genetic factors are of minor or no importance. No sex differences have been identified, Multivariate studies suggest that the extensive comorbidity between the PDs can be explained by three common genetic and environmental risk factors. The genetic factors do not reflect the DSM-IV cluster structure, but rather: i) broad vulnerability to PD pathology or negative emotionality; ii) high impulsivity/low agreeableness; and iii) introversion. Common genetic and environmental liability factors contribute to comorbidity between pairs or clusters of axis I and axis II disorders. Molecular genetic studies of PDs, mostly candidate gene association studies, indicate that genes linked to neurotransmitter pathways, especially in the serotonergic and dopaminergic systems, are involved. Future studies, using newer methods like genome-wide association, might take advantage of the use of endophenotypes.

  2. Epidemiology of Youth Suicide and Suicidal Behavior

    PubMed Central

    Cash, Scottye J.; Bridge, Jeffrey A.

    2010-01-01

    Purpose of Review Suicide is the third leading cause of death among young people in the U.S. and represents a significant public health problem worldwide. This review focuses on recent developments in our understanding of the epidemiology and risk factors for adolescent suicide and suicidal behavior. Recent Findings The suicide rate among children and adolescents in the U.S. has increased dramatically in recent years and has been accompanied by substantial changes in the leading methods of youth suicide, especially among young girls. Much work is currently underway to elucidate the relationships between psychopathology, substance use, child abuse, bullying, internet use, and youth suicidal behavior. Recent evidence also suggests sex-specific and moderating roles of gender in influencing risk for suicide and suicidal behavior. Summary Empirical research into the causal mechanisms underlying youth suicide and suicidal behavior is needed to inform early identification and prevention efforts. PMID:19644372

  3. Epidemiology of and Diagnostic Strategies for Toxoplasmosis

    PubMed Central

    Dardé, Marie-Laure

    2012-01-01

    Summary: The apicomplexan parasite Toxoplasma gondii was discovered a little over 100 years ago, but knowledge of its biological life cycle and its medical importance has grown in the last 40 years. This obligate intracellular parasite was identified early as a pathogen responsible for congenital infection, but its clinical expression and the importance of reactivations of infections in immunocompromised patients were recognized later, in the era of organ transplantation and HIV infection. Recent knowledge of host cell-parasite interactions and of parasite virulence has brought new insights into the comprehension of the pathophysiology of infection. In this review, we focus on epidemiological and diagnostic aspects, putting them in perspective with current knowledge of parasite genotypes. In particular, we provide critical information on diagnostic methods according to the patient's background and discuss the implementation of screening tools for congenital toxoplasmosis according to health policies. PMID:22491772

  4. Intrathoracic neoplasia: Epidemiology and etiology

    SciTech Connect

    Weller, R.E.

    1992-05-01

    Neoplasms of the thorax encompass those derived from the thoracic wall, trachea, mediastinum, lungs and pleura. They represent a wide variety of lesions including benign and malignant tumors arising from many tissues. The large surface area, 60 to 90 m{sup 2} in man, represented by the respiratory epithelium and associated thoracic structures are ideal targets for carcinogens carried by inspired air. The topic of discussion in this report is the epidemiology, etiology, and mechanisms of spontaneous intrathoracic neoplasia in animals and man. Much of what we know or suspect about thoracic neoplasia in animals has been extrapolated from experimentally-induced neoplasms.

  5. [DOHaD: epidemiological researches].

    PubMed

    Delpierre, Cyrille; Lepeule, Johanna; Cordier, Sylvaine; Slama, Remy; Heude, Barbara; Charles, Marie-Aline

    2016-01-01

    Epidemiological researches in the field of DOHaD are in favor of a role of early environment, including chemical (pesticides), physical (air pollution), nutritional or psychosocial environment, on child and adult health. Disentangling the different factors of environment that may affect health, especially over time, and identifying critical periods of exposure remains a major challenge. The biological mechanisms involved remain elusive in human beings. Nevertheless, it seems that whatever the nature of the exposure, epigenetic mechanisms are currently discussed to explain how the environment may alter biological systems over time.

  6. Epidemiology of youth sports concussion.

    PubMed

    Jinguji, Thomas M; Krabak, Brian J; Satchell, Emma K

    2011-11-01

    The overall prevalence of concussion is high school sports is unknown. In general, concussions in this age range occur much more frequently in games than in practice. Also for sports in which both sexes participate, reported concussion rates are higher for female than male high school athletes. Recent data show that the time required for return to play and resolution of symptoms is similar for women and men. Very little is known about the epidemiology of concussions in middle school-aged athletes and younger children.

  7. Some aspects of cancer epidemiology

    SciTech Connect

    Lilienfeld, A.M.

    1982-03-01

    Epidemiolgic studies have strongly suggested that a vast majority (80-90%) of cancers are caused by radiation, chemical and biologic agents; the remainder result from endogenous or genetic factors. Biologically, cancer is most probably the end result of a complex multistage process and therefore may be due to a sequence of exposures to different agents at each of these stages. This emphasizes the need to stress the study of interactions in epidemiologic studies to a greater extent than has been done thus far. Examples of the importance of interactions in several types of cancer are presented.

  8. Clinical and Translational Epidemiology Branch (CTEB)

    Cancer.gov

    The Clinical and Translational Epidemiology Branch focuses on factors that influence cancer progression, recurrence, survival, and other treatment outcomes, and factors associated with cancer development.

  9. Clinical Epidemiology Unit - overview of research areas

    Cancer.gov

    Clinical Epidemiology Unit (CEU) conducts etiologic research with potential clinical and public health applications, and leads studies evaluating population-based early detection and cancer prevention strategies

  10. Infection control in the new age of genomic epidemiology.

    PubMed

    Tang, Patrick; Croxen, Matthew A; Hasan, Mohammad R; Hsiao, William W L; Hoang, Linda M

    2017-02-01

    With the growing importance of infectious diseases in health care and communicable disease outbreaks garnering increasing attention, new technologies are playing a greater role in helping us prevent health care-associated infections and provide optimal public health. The microbiology laboratory has always played a large role in infection control by providing tools to identify, characterize, and track pathogens. Recently, advances in DNA sequencing technology have ushered in a new era of genomic epidemiology, where traditional molecular diagnostics and genotyping methods are being enhanced and even replaced by genomics-based methods to aid epidemiologic investigations of communicable diseases. The ability to analyze and compare entire pathogen genomes has allowed for unprecedented resolution into how and why infectious diseases spread. As these genomics-based methods continue to improve in speed, cost, and accuracy, they will be increasingly used to inform and guide infection control and public health practices.

  11. Use of monoclonal antibodies in an epidemiological marker system: a retrospective study of lung specimens from the 1976 outbreak of Legionnaires disease in Philadelphia by indirect fluorescent-antibody and enzyme-linked immunosorbent assay methods.

    PubMed Central

    Brown, S L; Bibb, W F; McKinney, R M

    1985-01-01

    Autopsy specimens of lung tissues from 15 patients that contracted legionellosis during the 1976 Philadelphia outbreak of Legionnaires disease were examined for the presence of Legionella organisms and soluble antigens by indirect fluorescent-antibody (IFA) testing and by an enzyme-linked immunosorbent assay (ELISA) with both polyclonal and monoclonal antibodies. In all 15 cases, at least one specimen was positive for Legionella pneumophila serogroup 1 (Lp-1) antigens by a polyclonal antibody ELISA system. Of the 15 cases tested for Lp-1, 9 were positive by a polyclonal antibody IFA test. Nine mouse monoclonal antibodies to Lp-1 gave essentially the same reactivity pattern with extracts from lung tissue homogenates as that obtained with a Philadelphia 1 culture extract by using a monoclonal antibody ELISA system. The same monoclonal antibody panel gave similar results when used in the IFA system with tissue homogenates. Monoclonal antibodies can be used as epidemiological marker systems with both IFA and ELISA testing. This study provides evidence that the 1976 common source outbreak in Philadelphia was probably caused by a single Lp-1 strain. ELISA testing of the soluble antigen of Lp-1 from lung tissue homogenate supernatants was more sensitive than IFA testing of the homogenates and should be extremely useful as either a primary test or as an adjunct to fluorescent antibody testing for legionellosis. Images PMID:3881470

  12. Measles - The epidemiology of elimination.

    PubMed

    Durrheim, David N; Crowcroft, Natasha S; Strebel, Peter M

    2014-12-05

    Tremendous progress has been made globally to reduce the contribution of measles to the burden of childhood deaths and measles cases have dramatically decreased with increased two dose measles-containing vaccine coverage. As a result the Global Vaccine Action Plan, endorsed by the World Health Assembly, has targeted measles elimination in at least five of the six World Health Organisation Regions by 2020. This is an ambitious goal, since measles control requires the highest immunisation coverage of any vaccine preventable disease, which means that the health system must be able to reach every community. Further, while measles remains endemic in any country, importations will result in local transmission and outbreaks in countries and Regions that have interrupted local endemic measles circulation. One of the lines of evidence that countries and Regions must address to confirm measles elimination is a detailed description of measles epidemiology over an extended period. This information is incredibly valuable as predictable epidemiological patterns emerge as measles elimination is approached and achieved. These critical features, including the source, size and duration of outbreaks, the seasonality and age-distribution of cases, genotyping pointers and effective reproduction rate estimates, are discussed with illustrative examples from the Region of the Americas, which eliminated measles in 2002, and the Western Pacific Region, which has established a Regional Verification Commission to review progress towards elimination in all member countries.

  13. Epidemiology of childhood food allergy.

    PubMed

    Dyer, Ashley A; Gupta, Ruchi

    2013-06-01

    Food allergy is a public health problem that affects nearly 6 million children in the United States. The extent to which children, families, and communities live with food allergies varies as much as the range of clinical symptoms associated with the disease itself. Food allergy is defined as the reproducible adverse event that elicits a pathologic immunoglobulin E (IgE)-mediated or non-IgE-mediated reaction. Once an allergic child ingests a specific food allergen, the reaction can result in clinical symptoms ranging from mild hives to life-threatening anaphylaxis.Not surprisingly, food allergies have been shown to limit social interactions and impair children's quality of life due to the ubiquity of food where children live, learn, and play. To ensure the safety of our children, the development of sound policy, clinical practice, and health programs must be informed by current research characterizing childhood food allergy at the population level. To set the stage for understanding the current evidence base, this article reviews: 1) epidemiology of childhood food allergy; 2) severity of symptoms; 3) geographic distribution of childhood food allergy; 4) tolerance; 5) economic impact of childhood food allergy; and 6) future directions in childhood food allergy epidemiological research.

  14. [Tuberculosis epidemiology in Mayotte Island].

    PubMed

    Woessner, J; Receveur, M C; Malvy, D; Taytard, A

    2008-10-01

    Mayotte is a French territory island, part of the Comoros Archipelago in the Indian Ocean with 200,000 inhabitants. The tuberculosis control program started in 1976, although available epidemiological data remains incomplete. We conducted a retrospective hospital-based survey in 202 outpatients and hospital medical records from the Hospital Centre of the main city to contribute to the epidemiological evaluation of tuberculosis patterns. The tuberculosis frequency remains unchanged since 2000. It affects a young population partly coming from the other neighbouring Comoro Islands (69%) with illegal immigrate status (53% in 2004). The systematic diagnostic screening efficiency of the condition appears marginal. Pulmonary involvement is the most frequent clinical manifestation (78%), although severe extrapulmonary manifestations are not exceptional. Co-infection with HIV and multi resistance to antituberculosis agents are not frequent. Up to 60% of cases have been proven to be bacteriologically linked. The notification rate remains critically low with an estimate of 39% of notifications to the local sanitary authorities in charge of secondary cases screening. The case coverage seems limited both by low socio-economical status and poor health facility accessibility The loss of follow up is dramatically high, 41% on the overall period, and up to 51% in 2004. Our results make mandatory the reinforcement of a tuberculosis survey and control involvement within the context of this French territory. Screening, care and follow up are to be implemented particularly for vulnerable and precarious groups and for patients.

  15. The dynamics of tuberculosis epidemiology.

    PubMed

    Rieder, Hans L

    2014-01-01

    A conceptual framework to study the epidemiologic basis of tuberculosis control is provided. The basic model to discuss the epidemiology of tuberculosis is based on a classification of tuberculosis based on its pathogenesis with exposure, latent infection, tuberculosis, and death from tuberculosis, showing the conditional probabilities leading from one to the next step in the chain of events. Historical data are utilized to demonstrate how the dynamics of tuberculosis over multiple decades have contributed to shape the present. It is shown that the key concept to understand the dynamics is related to current and past incidence and prevalence of latent infection with M. tuberculosis. The dynamics of the epidemic are shaped both by the behaviour of the causative organism of tuberculosis as well as the population structure and changes that take place in parallel in which M. tuberculosis thrives. Both the present and the future shape of the epidemic, as well as the principles applied to its control lie very much in the past of a society. While new risk factors such as HIV or diabetes have been or are emerging more strongly, it is noted that the majority of all new cases emerging cannot be pinned to one or the other such factor. It is the historical experience of a population that offers the most valuable key to understanding the present and the future.

  16. The cancer epidemiology of radiation.

    PubMed

    Wakeford, Richard

    2004-08-23

    Ionizing radiation has been the subject of intense epidemiological investigation. Studies have demonstrated that exposure to moderate-to-high levels can cause most forms of cancer, leukaemia and cancers of the breast, lung and thyroid being particularly sensitive to induction by radiation, especially at young ages at exposure. Predominant among these studies is the Life Span Study of the cohort of survivors of the atomic bombings of Japan in 1945, but substantial evidence is derived from groups exposed for medical reasons, occupationally or environmentally. Notable among these other groups are underground hard rock miners who inhaled radioactive radon gas and its decay products, large numbers of patients irradiated therapeutically and workers who received high doses in the nuclear weapons programme of the former USSR. The degree of carcinogenic risk arising from low levels of exposure is more contentious, but the available evidence points to an increased risk that is approximately proportional to the dose received. Epidemiological investigations of nonionizing radiation have established ultraviolet radiation as a cause of skin cancer. However, the evidence for a carcinogenic effect of other forms of nonionizing radiation, such as those associated with mobile telephones or electricity transmission lines, is not convincing, although the possibility of a link between childhood leukaemia and extremely low-frequency electromagnetic fields cannot be dismissed entirely.

  17. Epidemiology of nosocomial fungal infections.

    PubMed Central

    Fridkin, S K; Jarvis, W R

    1996-01-01

    This paper briefly reviews the current knowledge of the epidemiology and modes of transmission of nosocomial fungal infections and some of the therapeutic options for treating these diseases. In the mid-1980s, many institutions reported that fungi were common pathogens in nosocomial infections. Most, if not all, hospitals care for patients at risk for nosocomial fungal infections. The proportion in all nosocomial infections reportedly caused by Candida spp. increased from 2% in 1980 to 5% in 1986 to 1989. Numerous studies have identified common risk factors for acquiring these infections, most of which are very common among hospitalized patients; some factors act primarily by inducing immunosuppression (e.g., corticosteroids, chemotherapy, malnutrition, malignancy, and neutropenia), while others primarily provide a route of infection (e.g., extensive burns, indwelling catheter), and some act in combination. Non-albicans Candida spp., including fluconazole-resistant C. krusei and Torulopsis (C.) glabrata, have become more common pathogens. Newer molecular typing techniques can assist in the determination of a common source of infection caused by several fungal pathogens. Continued epidemiologic and laboratory research is needed to better characterize these pathogens and allow for improved diagnostic and therapeutic strategies. PMID:8894349

  18. Contemporary Renal Cell Cancer Epidemiology

    PubMed Central

    Chow, Wong-Ho; Devesa, Susan S.

    2010-01-01

    We analyzed renal cell cancer incidence patterns in the United States and reviewed recent epidemiologic evidence with regard to environmental and host genetic determinants of renal cell cancer risk. Renal cell cancer incidence rates continued to rise among all racial/ethnic groups in the United States, across all age groups, and for all tumor sizes, with the most rapid increases for localized stage disease and small tumors. Recent cohort studies confirmed the association of smoking, excess body weight, and hypertension with an elevated risk of renal cell cancer, and suggested that these factors can be modified to reduce the risk. There is increasing evidence for an inverse association between renal cell cancer risk and physical activity and moderate intake of alcohol. Occupational exposure to TCE has been positively associated with renal cell cancer risk in several recent studies, but its link with somatic mutations of the VHL gene has not been confirmed. Studies of genetic polymorphisms in relation to renal cell cancer risk have produced mixed results, but genome-wide association studies with larger sample size and a more comprehensive approach are underway. Few epidemiologic studies have evaluated risk factors by subtypes of renal cell cancer defined by somatic mutations and other tumor markers. PMID:18836333

  19. Epidemiology: second-rate science?

    PubMed

    Parascandola, M

    1998-01-01

    In recent years epidemiology has come under increasing criticism in regulatory and public arenas for being "unscientific." The tobacco industry has taken advantage of this, insisting for decades that evidence linking cigarettes and lung cancer falls short of proof. Moreover, many epidemiologists remain unduly skeptical and self-conscious about the status of their own causal claims. This situation persists in part because of a widespread belief that only the laboratory can provide evidence sufficient for scientific proof. Adherents of this view erroneously believe that there is no element of uncertainty or inductive inference in the "direct observation" of the laboratory researcher and that epidemiology provides mere "circumstantial" evidence. The historical roots of this attitude can be traced to philosopher John Stuart Mill and physiologist Claude Bernard and their influence on modern experimental thinking. The author uses the debate over cigarettes and lung cancer to examine ideas of proof in medical science and public health, concluding that inductive inference from a limited sample to a larger population is an element in all empirical science.

  20. Epidemiologic trends of leprosy for the 21st century.

    PubMed

    Schreuder, Pieter A M; Noto, Salvatore; Richardus, Jan Hendrik

    2016-01-01

    Major gaps still exist in the knowledge about leprosy, particularly with regard to how it spreads. Leprosy epidemiology remains complicated due to the specific characteristics of Mycobacterium leprae. To describe epidemiologic trends for the 21st century, the first part of this paper gives an overview of the epidemiology of leprosy, followed by past trends and the present situation of new-case detection as a proxy of the incidence. The third part, regarding predicted epidemiologic trends for the 21st century, elaborates on the main topic of this paper. With limited diagnostic tools to detect infection with M leprae, other methods are necessary to estimate trends in incidence and transmission. A computer program has been developed for modeling the transmission and control of leprosy (SIMLEP). The effect of failure to sustain early case detection beyond 2005 on leprosy incidence and case detection is shown. Important unanswered questions are whether the incubation period is contagious and how rapid close contacts of leprosy patients are infected. As long as such key questions remain unanswered, it will be difficult to estimate the impact of control strategies on the transmission of M leprae on resulting disease incidence. In the meantime we can expect that the global new-case detection trends will stay more or less stable or only decrease slightly for many years to come. There is a need of new preventive interventions to change this situation and reduce the incidence of leprosy in the 21st century.

  1. The Epidemiologic Transition: Changing Patterns of Mortality and Population Dynamics

    PubMed Central

    McKeown, Robert E.

    2009-01-01

    The epidemiologic transition describes changing patterns of population age distributions, mortality, fertility, life expectancy, and causes of death. A number of critiques of the theory have revealed limitations, including an insufficient account of the role of poverty in determining disease risk and mortality, a failure to distinguish adequately the risk of dying from a given cause or set of causes from the relative contributions of various causes of death to overall mortality, and oversimplification of the transition patterns, which do not fit neatly into either historical periods or geographic locations. Recent developments in epidemiologic methods reveal other limitations. A life course perspective prompts examination of changes in causal pathways across the life span when considering shifts in the age distribution of a population as described by the epidemiologic transition theory. The ecological model assumes multiple levels of determinants acting in complex and interrelated ways, with higher level determinants exhibiting emergent properties. Development, testing, and implementation of innovative approaches to reduce the risks associated with the sedentary lifestyle and hyper nutrition in developed countries should not overshadow the continuing threat from infectious diseases, especially resistant strains or newly encountered agents. Interventions must fit populations and the threats to health they experience, while anticipating changes that will emerge with success in some areas. This will require new ways of thinking that go beyond the epidemiologic transition theory. PMID:20161566

  2. Postlicensure epidemiology of childhood vaccination: the Danish experience.

    PubMed

    Hviid, Anders

    2006-10-01

    The efficacy, the ability to confer protection against a target disease and the safety of a vaccine are assessed in great detail before licensure. However, inherent limitations in the prelicensure assessment necessitate continued epidemiological evaluations of efficacy and safety issues after the introduction of vaccines into use. In Denmark, the opportunities available for epidemiological research are unique. In 2001, an initiative was undertaken to take advantage of these opportunities to study the postlicensure epidemiology of childhood vaccination with respect to effectiveness and safety. First, we describe the unique opportunities for postlicensure research in Denmark with respect to the data sources available and the epidemiological and statistical methods used. We then describe a number of recent postlicensure studies of effectiveness and safety that took advantage of these opportunities. Specifically, studies on the effectiveness of Haemophilus influenzae type b vaccination, the effectiveness of pertussis vaccination, the impact of a preschool pertussis booster on infant pertussis, measles-mumps-rubella vaccine and autism, thimerosal-containing vaccine and autism, measles-mumps-rubella vaccine and febrile seizures, childhood vaccination and Type 1 diabetes, and childhood vaccination and nontargeted infectious disease are discussed.

  3. Contrasting the epidemiological and evolutionary dynamics of influenza spatial transmission

    PubMed Central

    Viboud, Cécile; Nelson, Martha I.; Tan, Yi; Holmes, Edward C.

    2013-01-01

    In the past decade, rapid increases in the availability of high-resolution molecular and epidemiological data, combined with developments in statistical and computational methods to simulate and infer migration patterns, have provided key insights into the spatial dynamics of influenza A viruses in humans. In this review, we contrast findings from epidemiological and molecular studies of influenza virus transmission at different spatial scales. We show that findings are broadly consistent in large-scale studies of inter-regional or inter-hemispheric spread in temperate regions, revealing intense epidemics associated with multiple viral introductions, followed by deep troughs driven by seasonal bottlenecks. However, aspects of the global transmission dynamics of influenza viruses are still debated, especially with respect to the existence of tropical source populations experiencing high levels of genetic diversity and the extent of prolonged viral persistence between epidemics. At the scale of a country or community, epidemiological studies have revealed spatially structured diffusion patterns in seasonal and pandemic outbreaks, which were not identified in molecular studies. We discuss the role of sampling issues in generating these conflicting results, and suggest strategies for future research that may help to fully integrate the epidemiological and evolutionary dynamics of influenza virus over space and time. PMID:23382422

  4. Epidemiology of Chronic Pain in Denmark and Sweden

    PubMed Central

    Harker, Julie; Reid, Kim J.; Bekkering, Geertruida E.; Kellen, Eliane; Bala, Malgorzata M.; Riemsma, Rob; Worthy, Gill; Misso, Kate; Kleijnen, Jos

    2012-01-01

    Introduction. Estimates on the epidemiology of chronic pain vary widely throughout Europe. It is unclear whether this variation reflects true differences between populations or methodological factors. Information on the epidemiology of chronic pain can support decision makers in allocating adequate health care resources. Methods. In order to obtain epidemiological data on chronic pain in Denmark and Sweden, we conducted a literature review of epidemiological data primarily on chronic noncancer pain, prioritising studies of highest quality, recency, and validity by conducting a systematic search for relevant studies. Following quality assessment, data were summarised and assigned to the research questions. Results. The prevalence of moderate to severe noncancer pain was estimated at 16% in Denmark and 18% in Sweden. Chronic pain impacts negatively on perceived health status, quality of life and is associated with increased cost. Despite using pain medications, a large proportion of chronic pain sufferers have inadequate pain control. There was a lack of high-quality and low-bias studies with clear inclusion criteria. Conclusions. In both Denmark and Sweden, chronic pain is a common health problem which is potentially undertreated and warrants attention of health care workers, policy makers and researchers. Future research should utilise clear reporting guidelines to assist decision and policy makers, in this important area. PMID:22693667

  5. Epidemiology of Enterovirus D68 in Ontario

    PubMed Central

    Peci, Adriana; Winter, Anne-Luise; Warshawsky, Bryna; Booth, Tim F.; Eshaghi, AliReza; Li, Aimin; Perusini, Stephen; Olsha, Romy; Marchand-Austin, Alex; Kristjanson, Erik; Gubbay, Jonathan B.

    2015-01-01

    In August 2014, children’s hospitals in Kansas City, Missouri and Chicago, Illinois notified the Centers for Disease Control and Prevention (CDC) about increased numbers of pediatric patients hospitalized with severe respiratory illness (SRI). In response to CDC reports, Public Health Ontario Laboratories (PHOL) launched an investigation of patients being tested for enterovirus D-68 (EV-D68) in Ontario, Canada. The purpose of this investigation was to enhance our understanding of EV-D68 epidemiology and clinical features. Data for this study included specimens submitted for EV-D68 testing at PHOL from September 1, 2014 to October 31, 2014. Comparisons were made between patients who tested positive for the virus (cases) and those testing negative (controls). EV-D68 was identified in 153/907 (16.8%) of patients tested. In the logistic regression model adjusting for age, sex, setting and time to specimen collection, individuals younger than 20 years of age were more likely to be diagnosed with EV-D68 compared to those 20 and over, with peak positivity at ages 5–9 years. Cases were not more likely to be hospitalized than controls. Cases were more likely to be identified in September than October (OR 8.07; 95% CI 5.15 to 12.64). Routine viral culture and multiplex PCR were inadequate methods to identify EV-D68 due to poor sensitivity and inability to differentiate EV-D68 from other enterovirus serotypes or rhinovirus. Testing for EV-D68 in Ontario from July to December, 2014 detected the presence of EV-D68 virus among young children during September-October, 2014, with most cases detected in September. There was no difference in hospitalization status between cases and controls. In order to better understand the epidemiology of this virus, surveillance for EV-D68 should include testing of symptomatic individuals from all treatment settings and patient age groups, with collection and analysis of comprehensive clinical and epidemiological data. PMID:26599365

  6. Ophthalmic epidemiology in Europe: the "European Eye Epidemiology" (E3) consortium.

    PubMed

    Delcourt, Cécile; Korobelnik, Jean-François; Buitendijk, Gabriëlle H S; Foster, Paul J; Hammond, Christopher J; Piermarocchi, Stefano; Peto, Tunde; Jansonius, Nomdo; Mirshahi, Alireza; Hogg, Ruth E; Bretillon, Lionel; Topouzis, Fotis; Deak, Gabor; Grauslund, Jakob; Broe, Rebecca; Souied, Eric H; Creuzot-Garcher, Catherine; Sahel, José; Daien, Vincent; Lehtimäki, Terho; Hense, Hans-Werner; Prokofyeva, Elena; Oexle, Konrad; Rahi, Jugnoo S; Cumberland, Phillippa M; Schmitz-Valckenberg, Steffen; Fauser, Sascha; Bertelsen, Geir; Hoyng, Carel; Bergen, Arthur; Silva, Rufino; Wolf, Sebastian; Lotery, Andrew; Chakravarthy, Usha; Fletcher, Astrid; Klaver, Caroline C W

    2016-02-01

    The European Eye Epidemiology (E3) consortium is a recently formed consortium of 29 groups from 12 European countries. It already comprises 21 population-based studies and 20 other studies (case-control, cases only, randomized trials), providing ophthalmological data on approximately 170,000 European participants. The aim of the consortium is to promote and sustain collaboration and sharing of data and knowledge in the field of ophthalmic epidemiology in Europe, with particular focus on the harmonization of methods for future research, estimation and projection of frequency and impact of visual outcomes in European populations (including temporal trends and European subregions), identification of risk factors and pathways for eye diseases (lifestyle, vascular and metabolic factors, genetics, epigenetics and biomarkers) and development and validation of prediction models for eye diseases. Coordinating these existing data will allow a detailed study of the risk factors and consequences of eye diseases and visual impairment, including study of international geographical variation which is not possible in individual studies. It is expected that collaborative work on these existing data will provide additional knowledge, despite the fact that the risk factors and the methods for collecting them differ somewhat among the participating studies. Most studies also include biobanks of various biological samples, which will enable identification of biomarkers to detect and predict occurrence and progression of eye diseases. This article outlines the rationale of the consortium, its design and presents a summary of the methodology.

  7. Rabies Epidemiology and Control in Ecuador

    PubMed Central

    Ortiz-Prado, Esteban; Ponce-Zea, Jorge; Ramirez, Dario; Stewart-Ibarra, Anna M.; Armijos, Luciana; Yockteng, Jaime; Cárdenas, Washington B.

    2016-01-01

    Objective: Describe the epidemiology and the control effort for rabies in Ecuador. Methods: This observational study included data from the Ecuadorian National Institute of Census and Statistics (INEC), and mortality and morbidity data reported by the Ministry of Public Health and the National Institute for Social Security. We conducted a phylogeny analyses to compare the N gene from the Challenge Virus Standard (CVS) vaccine strain used in Ecuador with published Cosmopolitan, Asian and Sylvatic strains. Descriptive and inferential statistics were used to determine the significance of the data. Results: In 1996 Ecuador suffered the highest rate of rabies per capita in the Americas, with an incidence rate of 0.56 cases per 100 000 people per year. Human and canine rabies showed a sharp decline until 2012. Between 1994 and 2014, we found a correlation of 0.925 (p<0.01) between annual cases of dog and human rabies. In 2011, there was an epidemic of sylvatic rabies transmitted to people by vampire bats (Desmodus rotundus) in the Amazon region, specifically in Morona Santiago, leading to 11 fatalities. Phylogenetic analyses of the CVS vaccine N gene showed an association with urban canine rabies strains (the Cosmopolitan lineage and Asian strains), whereas sylvatic rabies, like those reported in the Amazon region, were found to be grouped in a different clade represented mainly by bat-derived strains. Conclusions: This study presents the first compilation of epidemiological data on rabies in Ecuador. The incidence of human and canine rabies, also known as urban rabies, has clearly decreased due to massive canine vaccination campaigns. Phylogenetic analysis of the prevailing vaccine used in the country showed a clear separation from bat-derived rabies, the source of recent rabies outbreaks. Efforts are ongoing to develop rabies vaccines that are highly specific to the rabies virus genotype circulating in the region, including sylvatic rabies. These efforts include the

  8. A human judgment approach to epidemiological forecasting

    PubMed Central

    Farrow, David C.; Brooks, Logan C.; Rosenfeld, Roni

    2017-01-01

    Infectious diseases impose considerable burden on society, despite significant advances in technology and medicine over the past century. Advanced warning can be helpful in mitigating and preparing for an impending or ongoing epidemic. Historically, such a capability has lagged for many reasons, including in particular the uncertainty in the current state of the system and in the understanding of the processes that drive epidemic trajectories. Presently we have access to data, models, and computational resources that enable the development of epidemiological forecasting systems. Indeed, several recent challenges hosted by the U.S. government have fostered an open and collaborative environment for the development of these technologies. The primary focus of these challenges has been to develop statistical and computational methods for epidemiological forecasting, but here we consider a serious alternative based on collective human judgment. We created the web-based “Epicast” forecasting system which collects and aggregates epidemic predictions made in real-time by human participants, and with these forecasts we ask two questions: how accurate is human judgment, and how do these forecasts compare to their more computational, data-driven alternatives? To address the former, we assess by a variety of metrics how accurately humans are able to predict influenza and chikungunya trajectories. As for the latter, we show that real-time, combined human predictions of the 2014–2015 and 2015–2016 U.S. flu seasons are often more accurate than the same predictions made by several statistical systems, especially for short-term targets. We conclude that there is valuable predictive power in collective human judgment, and we discuss the benefits and drawbacks of this approach. PMID:28282375

  9. [Recent new information on epidemiology of headache].

    PubMed

    Kavuk, I; Katsarava, Z; Stang, A; Agelink, M W; Diener, H C

    2004-04-01

    We reviewed the epidemiology of headache disorders for the most frequent primary headache-syndromes: migraine, tension-type headache and trigemino-autonomic headache syndromes. In the last years scientific data about headache disorders have increased. New studies investigated not only the prevalence of headaches, but also economic costs of this disorder. Epidemiologic headache research also investigates the quality of life.

  10. MEASURING RISKS IN HUMANS: THE PROMISE AND PRACTICE OF EPIDEMIOLOGY

    EPA Science Inventory


    Epidemiology has been considered the fundamental science of public health policy. The use of epidemiologic data in environmental health policy has been limited particularly in the environmental regulatory arena. Epidemiologic risk assessment (ERA) is different from risk ass...

  11. Wild-Type MIC Distributions and Epidemiological Cutoff Values for the Triazoles and Six Aspergillus spp. for the CLSI Broth Microdilution Method (M38-A2 Document)▿

    PubMed Central

    Espinel-Ingroff, A.; Diekema, D. J.; Fothergill, A.; Johnson, E.; Pelaez, T.; Pfaller, M. A.; Rinaldi, M. G.; Canton, E.; Turnidge, J.

    2010-01-01

    Clinical breakpoints have not been established for mold testing. Wild-type (WT) MIC distributions (organisms in a species/drug combination with no detectable acquired resistance mechanisms) were defined in order to establish epidemiologic cutoff values (ECVs) for five Aspergillus spp. and itraconazole, posaconazole, and voriconazole. Also, we have expanded prior ECV data for Aspergillus fumigatus. The number of available isolates varied according to the species/triazole combination as follows: 1,684 to 2,815 for A. fumigatus, 323 to 592 for A. flavus, 131 to 143 for A. nidulans, 366 to 520 for A. niger, 330 to 462 for A. terreus, and 45 to 84 for A. versicolor. CLSI broth microdilution MIC data gathered in five independent laboratories in Europe and the United States were aggregated for the analyses. ECVs expressed in μg/ml were as follows (percentages of isolates for which MICs were equal to or less than the ECV are in parentheses): A. fumigatus, itraconazole, 1 (98.8%); posaconazole, 0.5 (99.2%); voriconazole, 1 (97.7%); A. flavus, itraconazole, 1 (99.6%); posaconazole, 0.25 (95%); voriconazole, 1 (98.1%); A. nidulans, itraconazole, 1 (95%); posaconazole, 1 (97.7%); voriconazole, 2 (99.3%); A. niger, itraconazole, 2 (100%); posaconazole, 0.5 (96.9%); voriconazole, 2 (99.4%); A. terreus, itraconazole, 1 (100%); posaconazole, 0.5 (99.7%); voriconazole, 1 (99.1%); A. versicolor, itraconazole, 2 (100%); posaconazole, 1 (not applicable); voriconazole, 2 (97.5%). Although ECVs do not predict therapy outcome as clinical breakpoints do, they may aid in detection of azole resistance (non-WT MIC) due to cyp51A mutations, a resistance mechanism in some Aspergillus spp. These ECVs should be considered for inclusion in the future CLSI M38-A2 document revision. PMID:20592159

  12. Eco-epidemiology as anti-terrorism.

    PubMed

    Miller, Richard E

    Eco-epidemiology is a promising model for cross-disciplinary anti-terrorism. Derived from epidemiology's dominance of agents to illness and injury, the eco-epidemiological paradigm considers natural systems that generate causal pathways to disease and dynamic morbidity. Within this model is a hierarchy of systems interconnecting at biological, human, and social levels. Eco-epidemiology capitalizes on interacting components within and between system levels to identify contact patterns and apply mechanisms of control. Considering the complex and paradoxical nature of the threat-fear dynamic, a systematic, ecological approach would be more adaptive to terrorism's changing rules of engagement. To counter terrorism and nullify threat-fear, eco-epidemiology must be shared by public health researchers with threat assessment and harm reduction disciplines.

  13. Epidemiologic Change of Patients With Spinal Cord Injury

    PubMed Central

    Shin, Ji Cheol; Yu, Su Jin; Yang, Hea Eun; Yoon, Seo Yeon

    2013-01-01

    Objective To evaluate the epidemiologic change of patients with spinal cord injury who were admitted to a Rehabilitation Hospital, Yonsei University College of Medicine, during 1987-1996 and 2004-2008. Methods Medical records of 629 patients with spinal cord injury admitted to the Rehabilitation Hospital, Yonsei University College of Medicine, from 2004 to 2008 were collected and reviewed retrospectively. Results The male-to-female ratio decreased to 2.86:1, the mean age at injury increased, nontraumatic etiology increased, traffic accident remained to be the most common in traumatic spinal cord injury, and falling increased significantly. Tumor was the most common etiology in nontraumatic spinal cord injury, tetraplegia and incomplete injuries occurred more than paraplegia and complete injuries, indwelling catheter was the most common voiding method, and the duration of hospitalization decreased. Conclusion Many trends changed in epidemiology of spinal cord injury. PMID:23525183

  14. The Data Analysis In Epidemiology: A Methodology To Reduce Complexity

    NASA Astrophysics Data System (ADS)

    Esposito, F.

    1982-11-01

    The paper represents a trial of defining and testing a systematic methodology to study medical phenomena in which large sets of variables of an essentially qualitative kind are envolved. The methodology con sists in the organized application of the various methods of the Data Analysis and the Multivariate Statistics to the epidemiology in order to analyze phenomena very complex as to the numerousness and variety of the variables, to evaluate the environment influence, to understand the phenomenon evolution. The data analysis techniques play the role both of tools for synthesizing and validating indexes and of methods for formulating models of the disease propagation, by defining the prognostic function. The methodology is applied to define the epidemiological model of the Essential Arterial Hypertension.

  15. Epidemiological aspects of heart diseases

    PubMed Central

    Shi, Aimin; Tao, Ziqi; Wei, Peng; Zhao, Jing

    2016-01-01

    Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Coronary heart disease (CHD) is the main cause of mortality in heart patients following stroke, rheumatic heart disease and myocardial infarctions. Approximately 80% of individuals succumb to CVDs, due to poor living conditions in low and middle income families and malnutrition. Infectious diseases, human immunodeficiency, tuberculosis, malaria, high blood pressure or hypertension, obesity and overweight, and nutritional disorders including smoking, excessive alcohol consumption, high salt and sugar intake, as well as other factors are responsible for CVDs and CHDs in young as well as elderly individuals. The focus of the present review are recent epidemiological aspects of CVD and CHD as well as the usefulness of a Mediterranean diet for heart patients and the prevention of heart diseases. PMID:27602082

  16. [Epidemiology and prevention in dialysis].

    PubMed

    Cherubini, C; Barbera, G; Petrosillo, N; Di Giulio, S

    2003-01-01

    During the last years, prevention of hospital infections assumed the role of primary objective for active interventions and dedicated laws for safety in work areas and for facilities accreditation defined responsibilities and preventive measures to reduce the biological risk. Dialysis centers are areas where the infective risk is high but the strict application of the Universal Measures and of specific recommendations are sufficient to reduce the risk of diffusion and transmission of pathogens. The late referral of the ESRD patient, with or without infectious comorbidity, shows an intervention field, in which a local epidemiological survey gives useful data and stimulates the data management at hospital level (Epidemiologists and nefrologists) and family doctors, to improve the disease management of very complex and high cost patients.

  17. Epidemiology of blindness in Nepal*

    PubMed Central

    Brilliant, L. B.; Pokhrel, R. P.; Grasset, N. C.; Lepkowski, J. M.; Kolstad, A.; Hawks, W.; Pararajasegaram, R.; Brilliant, G. E.; Gilbert, S.; Shrestha, S. R.; Kuo, J.

    1985-01-01

    This report presents the major findings of the Nepal Blindness Survey, the first nationwide epidemiological survey of blindness, which was conducted in 1979-80. The survey was designed to gather data that could be used to estimate the prevalence and causes of blindness in the country. Ancillary studies were conducted to obtain information on socioeconomic correlates and other risk factors of blinding conditions and patterns of health care utilization. The nationwide blindness prevalence rate is 0.84%. Cataract is the leading cause of blindness, accounting for over 80% of all avoidable blindness. Trachoma is the most prevalent blinding condition, affecting 6.5% of the population. Very few cases of childhood blindness were detected. The implications of the survey findings for programme planning, health manpower development, and health education are discussed. PMID:3874717

  18. Overdiagnosis: epidemiologic concepts and estimation.

    PubMed

    Bae, Jong-Myon

    2015-01-01

    Overdiagnosis of thyroid cancer was propounded regarding the rapidly increasing incidence in South Korea. Overdiagnosis is defined as 'the detection of cancers that would never have been found were it not for the screening test', and may be an extreme form of lead bias due to indolent cancers, as is inevitable when conducting a cancer screening programme. Because it is solely an epidemiological concept, it can be estimated indirectly by phenomena such as a lack of compensatory drop in post-screening periods, or discrepancies between incidence and mortality. The erstwhile trials for quantifying the overdiagnosis in screening mammography were reviewed in order to secure the data needed to establish its prevalence in South Korea.

  19. Epidemiology and treatment of mucormycosis.

    PubMed

    Lewis, Russell E; Kontoyiannis, Dimitrios P

    2013-09-01

    Mucormycosis is an uncommon but aggressive opportunistic fungal infection that afflicts patients with severe underlying immunosuppression, uncontrolled hyperglycemia and/or ketoacidosis, patients with iron overload resulting from frequent blood transfusions or blood disorders and occasionally healthy patients who are inoculated with fungal spores through traumatic injuries. The clinical presentation of mucormycosis is initially indistinguishable from other common infections, and if not diagnosed early and aggressively treated, it is almost always fatal. In this article we summarize recent changes in the epidemiology of mucormycosis, discuss diagnostic and clinical clues suggestive of the infection and provide a general strategy for managing the infection in the absence of data from well-controlled, prospective clinical trials.

  20. Epidemiology of Haemophilus ducreyi Infections.

    PubMed

    González-Beiras, Camila; Marks, Michael; Chen, Cheng Y; Roberts, Sally; Mitjà, Oriol

    2016-01-01

    The global epidemiology of Haemophilus ducreyi infections is poorly documented because of difficulties in confirming microbiological diagnoses. We evaluated published data on the proportion of genital and nongenital skin ulcers caused by H. ducreyi before and after introduction of syndromic management for genital ulcer disease (GUD). Before 2000, the proportion of GUD caused by H. ducreyi ranged from 0.0% to 69.0% (35 studies in 25 countries). After 2000, the proportion ranged from 0.0% to 15.0% (14 studies in 13 countries). In contrast, H. ducreyi has been recently identified as a causative agent of skin ulcers in children in the tropical regions; proportions ranged from 9.0% to 60.0% (6 studies in 4 countries). We conclude that, although there has been a sustained reduction in the proportion of GUD caused by H. ducreyi, this bacterium is increasingly recognized as a major cause of nongenital cutaneous ulcers.

  1. Epidemiology of Haemophilus ducreyi Infections

    PubMed Central

    González-Beiras, Camila; Marks, Michael; Chen, Cheng Y.; Roberts, Sally

    2016-01-01

    The global epidemiology of Haemophilus ducreyi infections is poorly documented because of difficulties in confirming microbiological diagnoses. We evaluated published data on the proportion of genital and nongenital skin ulcers caused by H. ducreyi before and after introduction of syndromic management for genital ulcer disease (GUD). Before 2000, the proportion of GUD caused by H. ducreyi ranged from 0.0% to 69.0% (35 studies in 25 countries). After 2000, the proportion ranged from 0.0% to 15.0% (14 studies in 13 countries). In contrast, H. ducreyi has been recently identified as a causative agent of skin ulcers in children in the tropical regions; proportions ranged from 9.0% to 60.0% (6 studies in 4 countries). We conclude that, although there has been a sustained reduction in the proportion of GUD caused by H. ducreyi, this bacterium is increasingly recognized as a major cause of nongenital cutaneous ulcers. PMID:26694983

  2. [Scientific journalism and epidemiological risk].

    PubMed

    Luiz, Olinda do Carmo

    2007-01-01

    The importance of the communications media in the construction of symbols has been widely acknowledged. Many of the articles on health published in the daily newspapers mention medical studies, sourced from scientific publications focusing on new risks. The disclosure of risk studies in the mass media is also a topic for editorials and articles in scientific journals, focusing the problem of distortions and the appearance of contradictory news items. The purpose of this paper is to explore the meaning and content of disclosing scientific risk studies in large-circulation daily newspapers, analyzing news items published in Brazil and the scientific publications used as their sources during 2000. The "risk" is presented in the scientific research projects as a "black box" in the meaning of Latour, with the news items downplaying scientific disputes and underscoring associations between behavioral habits and the occurrence of diseases, emphasizing individual aspects of the epidemiological approach, to the detriment of the group.

  3. Epidemiology and control of trypanosomosis.

    PubMed

    Chadenga, V

    1994-12-01

    Tsetse-transmitted trypanosomosis remains a major constraint to the development of agriculture, particularly to that of livestock production in sub-Saharan Africa. It is estimated that 10 million km2 of Africa are tsetse infested, exposing some 50 million people and 60 million cattle to the risk of trypanosomosis. The epidemiology of the disease is complex and is greatly influenced by management and farming practices. The different control strategies are reviewed and their comparative advantages assessed. It is concluded that eradication of tsetse flies, while desirable, is rarely achieved. It is perhaps more realistic to aim for disease suppression, with vector-control campaigns linked to sustainable land-use programmes. Nevertheless, progressive tsetse eradication remains the long-term goal.

  4. [Lead poisoning: towards a paleo-epidemiologic re-interpretation?].

    PubMed

    Bourdieu, Anne

    2014-01-01

    Lead is a major public health issue. Its use has been increasing since Neolithic times, climaxing in the Ancient Rome and the nineteenth century. Defining the frequency of plumbism before modern times proves to be a difficult matter because of its various and delayed symptoms, and of diagenetic processes affecting bones. After reviewing various methods of lead measurement in bone and tooth, we will expose ways to ascertain lead measurement interpretation in order to estimate the epidemiology of plumbism in ancient times.

  5. Reducing Prostate Cancer Disparities through Behavioral and Biologic Epidemiologic Approaches

    DTIC Science & Technology

    2010-09-01

    accomplish four main objectives: 1) To increase knowledge in and integrate the application of biologic and behavioral epidemiological methods in...of an R03 on the prognostic effect of vitamin D on prostate cancer. The objectives of this training award include: 1) To increase knowledge in and...most at-risk groups. With the knowledge and experience gained from this award, I will make significant contributions to the development of effective

  6. Reducing Prostate Cancer Disparities Through Behavioral and Biologic Epidemiologic Approaches

    DTIC Science & Technology

    2010-09-01

    accomplish four main objectives: 1) To increase knowledge in and integrate the application of biologic and behavioral epidemiological methods in...of an R03 on the prognostic effect of vitamin D on prostate cancer. The objectives of this training award include: 1) To increase knowledge in and...most at-risk groups. With the knowledge and experience gained from this award, I will make significant contributions to the development of effective

  7. Prevention, communication and equity in environmental epidemiology: ethical issues.

    PubMed

    Pagliarani, Giovanna; Botti, Caterina

    2011-01-01

    In environmental epidemiology research, decisions about when and how to intervene requires adequate ethical reflection. In fact, different kinds of issues may arise about: research methods and knowledge production; management of the results in terms of their overall assessments or for the implementation of preventive actions; reclamation intervention. In this contribution we propose to consider three topics we regard as crucial to this ethical debate: the reporting of conclusive research data; the correct application of the precautionary principle; and the environmental equity issues.

  8. Epidemiological studies of esophageal cancer in the era of genome-wide association studies

    PubMed Central

    Wang, An-Hui; Liu, Yuan; Wang, Bo; He, Yi-Xuan; Fang, Ye-Xian; Yan, Yong-Ping

    2014-01-01

    Esophageal cancer (EC) caused about 395000 deaths in 2010. China has the most cases of EC and EC is the fourth leading cause of cancer death in China. Esophageal squamous cell carcinoma (ESCC) is the predominant histologic type (90%-95%), while the incidence of esophageal adenocarcinoma (EAC) remains extremely low in China. Traditional epidemiological studies have revealed that environmental carcinogens are risk factors for EC. Molecular epidemiological studies revealed that susceptibility to EC is influenced by both environmental and genetic risk factors. Of all the risk factors for EC, some are associated with the risk of ESCC and others with the risk of EAC. However, the details and mechanisms of risk factors involved in the process for EC are unclear. The advanced methods and techniques used in human genome studies bring a great opportunity for researchers to explore and identify the details of those risk factors or susceptibility genes involved in the process of EC. Human genome epidemiology is a new branch of epidemiology, which leads the epidemiology study from the molecular epidemiology era to the era of genome wide association studies (GWAS). Here we review the epidemiological studies of EC (especially ESCC) in the era of GWAS, and provide an overview of the general risk factors and those genomic variants (genes, SNPs, miRNAs, proteins) involved in the process of ESCC. PMID:25133033

  9. A review of the epidemiology and treatment of Peyronie’s disease

    PubMed Central

    Ostrowski, Kevin A; Gannon, John R; Walsh, Thomas J

    2016-01-01

    Introduction Peyronie’s disease (PD) has significant effect on patients and their partners. We provide a current review of the epidemiology as well as the nonsurgical and surgical treatment of PD. Materials and methods Review of literature pertaining to PD with focus on epidemiology and treatment options. Conclusion PD is common and likely underreported. The availability of new and highly effective treatment options will catalyze patient awareness and subsequently the prevalence of disease. PMID:27200305

  10. The Epidemiology of Cancer Among Police Officers

    PubMed Central

    Wirth, Michael; Vena, John E.; Smith, Emily K.; Bauer, Sarah E.; Violanti, John; Burch, James

    2013-01-01

    Background This review summarizes peer-reviewed studies examining cancer risks among police officers. It provides an overview of existing research limitations and uncertainties and the plausible etiologic risk factors associated with cancer in this understudied occupation. Methods Previous cancer studies among police officers were obtained via a systematic review of the MEDLINE, CABDirect, and Web of Science bibliographic databases. Results Quality observational studies of cancer among police officers are sparse and subject to limitations in exposure assessment and other methods. Results from three studies suggested possible increased mortality risks for all cancers, and cancers of the colon, kidney, digestive system, esophagus, male breast, and testis, as well as Hodgkin’s disease. Few incidence studies have been performed, and results have been mixed, although some associations with police work have been observed for thyroid, skin, and male breast cancer. Conclusions Police are exposed to a mix of known or suspected agents or activities that increase cancer risk. Epidemiologic evidence to date is sparse and inconsistent. There is a critical need for more research to understand the biological and social processes underlying exposures and the suggested disproportionate risks and to identify effective prevention strategies. PMID:23255299

  11. The Epidemiology, Prevention, and Detection of Melanoma

    PubMed Central

    Riker, Adam I.; Zea, Nicolas; Trinh, Tan

    2010-01-01

    We are seeing a record number of newly diagnosed skin cancers worldwide, with the incidence of melanoma increasing at a faster rate than almost all other cancers. As clinicians, we will have, by far, the greatest impact on reducing this incidence through better methods of early detection of melanoma and proven prevention methods and techniques. The medical community must enhance its efforts to increase its training of new health care personnel who are capable of diagnosing and treating this record number of patients with skin cancer. We must also try to increase the access to our limited number of dermatologists and provide novel ways of patient education such as through skin self-examinations, total body photography, and improved education for our children. By providing easier access to skin examinations, we will increase our chances of detecting melanoma in its earliest and most curable form. The dangers of indoor tanning beds and salons must be transparent to those that use them, focusing on expanding the oversight of such facilities by our local and federal governmental agencies while establishing legislation in several states to further limit their use to our youth, who are especially at high risk for developing melanoma in the future. This review will focus on the epidemiology, prevention, and detection of melanoma. PMID:21603359

  12. Epidemiology in Latin America and the Caribbean: current situation and challenges

    PubMed Central

    Barreto, Sandhi M; Miranda, Jaime J; Figueroa, J Peter; Schmidt, Maria Inês; Munoz, Sergio; Kuri-Morales, P Pablo; Silva, Jarbas B

    2012-01-01

    Background This article analyses the epidemiological research developments in Latin America and the Caribbean (LAC). It integrates the series commissioned by the International Epidemiological Association to all WHO Regions to identify global opportunities to promote the development of epidemiology. Methods Health situations of the regions were analysed based on published data on selected mortality, morbidity and risk factors. Epidemiological publication output by country was estimated by Medline bibliometrics. Internet and literature searches and data provided by key informants were used to describe perspectives on epidemiological training, research and funding. Findings Despite important advances in recent decades, LAC remains the world's most unequal region. In 2010, 10% of the LAC's people still lived in conditions of multidimensional poverty, with huge variation among countries. The region has experienced fast and complex epidemiological changes in past decades, combining increasing rates of non-communicable diseases and injuries, and keeping uncontrolled many existing endemic and emerging diseases. Overall, epidemiological publications per year increased from 160 articles between 1961 and 1970 to 2492 between 2001 and 2010. The increase in papers per million inhabitants in the past three decades varied from 57% in Panama to 1339% in Paraguay. Universities are the main epidemiological training providers. There are at least 34 universities and other institutions in the region that offer postgraduate programmes at the master’s and doctoral levels in epidemiology or public health. Most LAC countries rely largely on external funding and donors to initiate and sustain long-term research efforts. Despite the limited resources, the critical mass of LAC researchers has produced significant scientific contributions. Future needs The health research panorama of the region shows enormous regional discrepancies, but great prospects. Improving research and human resources

  13. The perfect food and the filth disease: milk-borne typhoid and epidemiological practice in late Victorian Britain.

    PubMed

    Steere-Williams, Jacob

    2010-10-01

    This article explores the initial set of epidemiological investigations in Victorian Britain that linked typhoid fever to milk from dairy cattle. Because Victorian epidemiologists first recognized the milk-borne route in outbreaks of typhoid fever, these investigations served as a model for later studies of milk-borne scarlet fever, diphtheria, and perhaps tuberculosis. By focusing on epidemiological practices conducted by Medical Inspectors at the Medical Department of the Local Government Board and Medical Officers of Health, I show that Victorian epidemiology was committed to field-based, observational methods that defined the professional nature of the discipline and its theories and practices. Epidemiological investigations of milk-borne typhoid heated up several important public health debates in the second half of the nineteenth century, and demonstrate how Victorian epidemiology was not solely wedded to examining population studies using statistical methods, as historians have typically argued, but also relied on observational case-tracing in individuals, animals, and even environments.

  14. Genetic epidemiology of breast cancer.

    PubMed

    Thompson, W D

    1994-07-01

    It has been recognized for some time that a family history of breast cancer is associated rather strongly with a woman's own risk of developing the disease. Recent segregation analyses of population-based data on familial patterns provide evidence for a rare autosomal dominant allele that increases a carrier's susceptibility to breast cancer. The estimated proportion of breast cancer patients who carry this allele declines sharply with age at diagnosis. Empirical estimates of the risk associated with particular patterns of family history of breast cancer indicate the following: (1) having any first-degree relative with breast cancer increases a woman's risk of breast cancer 1.5-3-fold, depending on age, (2) having multiple first degree relatives affected is associated with particularly elevated risks, (3) having a second-degree relative affected increases the risk by approximately 50%, (4) affected family members on the maternal side and the paternal side contribute similarly to the risk, (5) a family history of breast cancer is associated with bilateral disease, and (6) breast cancer in males is associated with breast cancer in female relatives in much the same way as is breast cancer in women. Ovarian cancer clearly has been shown to be associated with breast cancer in families, and genetic linkage has provided strong evidence for a breast-ovarian cancer gene located somewhere on chromosome 17q. At the population level, having a first degree relative with ovarian cancer may be at least as predictive of a woman's risk for developing breast cancer as is having a second-degree relative with breast cancer. Considerably weaker evidence points to a possible familial relationship between breast and endometrial cancer and between breast cancer in women and prostatic cancer in males. The clinical applications of the genetic epidemiology of breast cancer are complicated by uncertainty as to the efficacy of mammographic screening in women under the age of 50. For the vast

  15. Systems Epidemiology: What’s in a Name?

    PubMed Central

    Dammann, O.; Gray, P.; Gressens, P.; Wolkenhauer, O.; Leviton, A.

    2014-01-01

    Systems biology is an interdisciplinary effort to integrate molecular, cellular, tissue, organ, and organism levels of function into computational models that facilitate the identification of general principles. Systems medicine adds a disease focus. Systems epidemiology adds yet another level consisting of antecedents that might contribute to the disease process in populations. In etiologic and prevention research, systems-type thinking about multiple levels of causation will allow epidemiologists to identify contributors to disease at multiple levels as well as their interactions. In public health, systems epidemiology will contribute to the improvement of syndromic surveillance methods. We encourage the creation of computational simulation models that integrate information about disease etiology, pathogenetic data, and the expertise of investigators from different disciplines. PMID:25598870

  16. Epidemiology, Diagnosis, and Antimicrobial Treatment of Acute Bacterial Meningitis

    PubMed Central

    Brouwer, Matthijs C.; Tunkel, Allan R.; van de Beek, Diederik

    2010-01-01

    Summary: The epidemiology of bacterial meningitis has changed as a result of the widespread use of conjugate vaccines and preventive antimicrobial treatment of pregnant women. Given the significant morbidity and mortality associated with bacterial meningitis, accurate information is necessary regarding the important etiological agents and populations at risk to ascertain public health measures and ensure appropriate management. In this review, we describe the changing epidemiology of bacterial meningitis in the United States and throughout the world by reviewing the global changes in etiological agents followed by specific microorganism data on the impact of the development and widespread use of conjugate vaccines. We provide recommendations for empirical antimicrobial and adjunctive treatments for clinical subgroups and review available laboratory methods in making the etiological diagnosis of bacterial meningitis. Finally, we summarize risk factors, clinical features, and microbiological diagnostics for the specific bacteria causing this disease. PMID:20610819

  17. Mental health epidemiological research in South America: recent findings

    PubMed Central

    Silva de Lima, Maurício; Garcia de Oliveira Soares, Bernardo; de Jesus Mari, Jair

    2004-01-01

    This paper aims to review the recent mental health epidemiological research conducted in South America. The Latin American and the Caribbean (LILACS) database was searched from 1999 to 2003 using a specific strategy for identification of cohort, case-control and cross-sectional population-based studies in South America. The authors screened references and identified relevant studies. Further studies were obtained contacting local experts in epidemiology. 140 references were identified, and 12 studies were selected. Most selected studies explored the prevalence and risk factors for common mental disorders, and several of them used sophisticated methods of sample selection and analysis. There is a need for improving the quality of psychiatric journals in Latin America, and for increasing the distribution and access to research data. Regionally relevant problems such as violence and substance abuse should be considered in designing future investigations in this area. PMID:16633474

  18. Molecular Epidemiology of Human Intestinal Amoebas in Iran

    PubMed Central

    Hooshyar, H; Rostamkhani, P; Rezaian, M

    2012-01-01

    Many microscopic-based epidemiological surveys on the prevalence of human intestinal pathogenic and non-pathogenic protozoa including intestinal amoeba performed in Iran show a high prevalence of human intestinal amoeba in different parts of Iran. Such epidemiological studies on amoebiasis are confusing, mainly due to recently appreciated distinction between the Entamoeba histolytica, E. dispar and E. moshkovskii. Differential diagnosis can be done by some methods such as PCR-based methods, monoclonal antibodies and the analysis of isoenzyme typing, however the molecular study of these protozoa in Iran is low. Based on molecular studies, it seems that E. dispar is predominant species especially in the central and northern areas of Iran and amoebiasis due to E. histolytica is a rare infection in the country. It is suggested that infection with E. moshkovskii may be common among Iranians. Considering the importance of molecular epidemiology of amoeba in Iran and also the current data, the present study reviews the data currently available on the molecular distribution of intestinal human amoeba in Iran. PMID:23193500

  19. John Snow’s legacy: epidemiology without borders

    PubMed Central

    Fine, Paul; Victora, Cesar G; Rothman, Kenneth J; Moore, Patrick S; Chang, Yuan; Curtis, Val; Heymann, David L; Slutkin, Gary; May, Robert M; Patel, Vikram; Roberts, Ian; Wortley, Richard; Torgerson, Carole; Deaton, Angus

    2013-01-01

    This Review provides abstracts from a meeting held at the London School of Hygiene and Tropical Medicine, on April 11–12, 2013, to celebrate the legacy of John Snow. They describe conventional and unconventional applications of epidemiological methods to problems ranging from diarrhoeal disease, mental health, cancer, and accident care, to education, poverty, financial networks, crime, and violence. Common themes appear throughout, including recognition of the importance of Snow’s example, the philosophical and practical implications of assessment of causality, and an emphasis on the evaluation of preventive, ameliorative, and curative interventions, in a wide variety of medical and societal examples. Almost all self-described epidemiologists nowadays work within the health arena, and this is the focus of most of the societies, journals, and courses that carry the name epidemiology. The range of applications evident in these contributions might encourage some of these institutions to consider broadening their remits. In so doing, they may contribute more directly to, and learn from, non-health-related areas that use the language and methods of epidemiology to address many important problems now facing the world. PMID:23582396

  20. Consensus statement on assessment of waterpipe smoking in epidemiological studies.

    PubMed

    Maziak, Wasim; Ben Taleb, Ziyad; Jawad, Mohammed; Afifi, Rima; Nakkash, Rima; Akl, Elie A; Ward, Kenneth D; Salloum, Ramzi G; Barnett, Tracey E; Primack, Brian A; Sherman, Scott; Cobb, Caroline O; Sutfin, Erin L; Eissenberg, Thomas

    2016-05-10

    Numerous epidemiological accounts suggest that waterpipe smoking (aka hookah, shisha, narghile) has become a global phenomenon, especially among youth. The alarming spread of waterpipe and accumulating evidence of its addictive and harmful effects represent a new threat in the global fight to limit tobacco-related morbidity and mortality. In response to waterpipe's alarming trends, major public health and tobacco control organisations have started or are considering systematic collection of data about waterpipe smoking to monitor its trends and assess its harmful effects in different societies. Such plans require coordination and agreement on epidemiological measurement tools that reflect the uniqueness of this tobacco use method, and at the same time allow comparison of waterpipe trends across time and place, and with other tobacco use methods. We started a decade ago our work to develop standardised measures and definitions for the assessment of waterpipe smoking in epidemiological studies. In this communication, we try to expand and update these assessment tools in light of our increased knowledge and understanding of waterpipe use patterns, its context and marketing, as well as the need for evidence-guided policies and regulations to curb its spread. We have assembled for this purpose a group of leading waterpipe researchers worldwide, and worked through an iterative process to develop the suggested instruments and definitions based on what we know currently about the waterpipe epidemic. While the suggested measures are by no means comprehensive, we hope that they can provide the building blocks for standard and comparable surveillance of waterpipe smoking globally.

  1. [The other epidemiologic transition: landmarks in the development of risk factor epidemiology in Colombia].

    PubMed

    Idrovo, Alvaro Javier; Eslava, Juan Carlos; Ruiz-Rodríguez, Myriam; Rodríguez, Jorge Martín

    2008-12-01

    The history of risk factor epidemiology is detailed as it emerged in Colombia as well as more recent developments. The origins of risk factor epidemiology are described in the context of the national health situation of the mid-20th century, when changes were occurring in the profiles of infectious and nutritional diseases in comparison to chronic diseases and traumatisms. The main achievements in the history of national risk factor epidemiology are described, including: the studies on endemic goiter, gastric and uterine cervical cancers, adverse effects of child undernourishment, and the institution of local health surveys. The important influence of the Rockefeller Foundation and the Pan American Health Organization on the epidemiology education in Colombia is highlighted. Finally, the main, currently active research lines in epidemiology are described. Investigative guidelines are suggested for future historians of Colombian public health and epidemiology.

  2. Prostate cancer in Brazil and Latin America: epidemiology and screening

    PubMed Central

    Tourinho-Barbosa, Rafael Rocha; Pompeo, Antonio Carlos Lima; Glina, Sidney

    2016-01-01

    ABSTRACT Introduction: Prostate cancer is one of the tumors with higher incidence and mortality among men in the World. Epidemiological data are influenced by life expectancy of population, available diagnostic methods, correct collection of data and quality of health services. Screening of the disease is not standardized around the World. Up till now there is no consensus about the risks versus benefits of early detection. There are still missing data about this pathology in Latin America. Objective: to revise current epidemiologic situation and early diagnosis policies of prostate cancer in Brazil and Latin America. Materials and Methods: Medline, Cochrane Library and SciELO databases were reviewed on the subject of epidemiology and screening of prostate cancer. Screening research was performed in websites on national public health organizations and Latin America. Screening recommendations were obtained from those governmental organizations and from Latin American urological societies and compared to the most prominent regulatory agencies and societies of specialists and generalists from around the World. Results: Brazil and Latin America have a special position in relation to incidence and mortality of prostate cancer. In Brazil, it occupies the first position regarding incidence of cancer in men and the second cause of mortality. Central America has the highest rate of mortality of the continent with lower incidence/mortality ratios. Screening recommendations are very distinct, mainly among regulatory organs and urological societies. Conclusion: prostate cancer epidemiology is an important health public topic. Data collection related to incidence and mortality is still precarious, especially in less developed countries. It is necessary to follow-up long term screening studies results in order to conclude its benefits. PMID:27622278

  3. Snowboard traumatology: an epidemiological study.

    PubMed

    Pigozzi, F; Santori, N; Di Salvo, V; Parisi, A; Di-Luigi, L

    1997-06-01

    In the past 10 years, snowboarding has become a popular winter sport among young people, and the number of accidents has increased proportionately. The incidence of traumas from snowboarding is shown to be 4 to 6 for every 1000 medical examinations, which is similar to that of downhill skiing. However, other important statistical differences exist between the two sports. This study of 106 snowboarding-related injury cases analyzes the epidemiology of these injuries in Italy. Results found that 45.1% of injuries are located in the upper limbs and that significant advantages are obtained with the introduction of guards to protect the upper limbs during descent. Serious ligament injuries to the knee are more rare in snowboarding than in downhill skiing. In both sports, injuries are more common with rigid boots, which lead to a higher incidence of injury to the upper limbs. Finally, a high percentage of injury to beginners was found in this study. Training courses for those who are considering taking up the sport of snowboarding could significantly lower their risk of trauma.

  4. Global Epidemiology of Plasmodium vivax

    PubMed Central

    Howes, Rosalind E.; Battle, Katherine E.; Mendis, Kamini N.; Smith, David L.; Cibulskis, Richard E.; Baird, J. Kevin; Hay, Simon I.

    2016-01-01

    Plasmodium vivax is the most widespread human malaria, putting 2.5 billion people at risk of infection. Its unique biological and epidemiological characteristics pose challenges to control strategies that have been principally targeted against Plasmodium falciparum. Unlike P. falciparum, P. vivax infections have typically low blood-stage parasitemia with gametocytes emerging before illness manifests, and dormant liver stages causing relapses. These traits affect both its geographic distribution and transmission patterns. Asymptomatic infections, high-risk groups, and resulting case burdens are described in this review. Despite relatively low prevalence measurements and parasitemia levels, along with high proportions of asymptomatic cases, this parasite is not benign. Plasmodium vivax can be associated with severe and even fatal illness. Spreading resistance to chloroquine against the acute attack, and the operational inadequacy of primaquine against the multiple attacks of relapse, exacerbates the risk of poor outcomes among the tens of millions suffering from infection each year. Without strategies accounting for these P. vivax-specific characteristics, progress toward elimination of endemic malaria transmission will be substantially impeded. PMID:27402513

  5. Global Epidemiology of Campylobacter Infection

    PubMed Central

    Kaakoush, Nadeem O.; Castaño-Rodríguez, Natalia; Mitchell, Hazel M.

    2015-01-01

    SUMMARY Campylobacter jejuni infection is one of the most widespread infectious diseases of the last century. The incidence and prevalence of campylobacteriosis have increased in both developed and developing countries over the last 10 years. The dramatic increase in North America, Europe, and Australia is alarming, and data from parts of Africa, Asia, and the Middle East indicate that campylobacteriosis is endemic in these areas, especially in children. In addition to C. jejuni, there is increasing recognition of the clinical importance of emerging Campylobacter species, including Campylobacter concisus and Campylobacter ureolyticus. Poultry is a major reservoir and source of transmission of campylobacteriosis to humans. Other risk factors include consumption of animal products and water, contact with animals, and international travel. Strategic implementation of multifaceted biocontrol measures to reduce the transmission of this group of pathogens is paramount for public health. Overall, campylobacteriosis is still one of the most important infectious diseases that is likely to challenge global health in the years to come. This review provides a comprehensive overview of the global epidemiology, transmission, and clinical relevance of Campylobacter infection. PMID:26062576

  6. Epidemiology of salmonellosis in Arkansas.

    PubMed

    Schutze, G E; Flick, E L; Pope, S K; Lofgren, J P; Kirby, R S

    1995-02-01

    Human salmonellosis continues to be a major public health issue. Our epidemiologic review of cases from 1989 to 1992 was done to define the current reported rate of infection due to Salmonella species for the state of Arkansas, which might be expected to have higher rates of infection because it is a leading producer of poultry. Results showed that the reported case rate in Arkansas (18.0/100,000) did not differ from that of the United States at large (18.6/100,000). Age-specific rates, however, showed that children less than 1 year of age in Arkansas were infected at a higher rate than those in the remainder of the nation. Salmonella newport and S typhimurium were the most commonly isolated serotypes. Individuals living in a county with poultry processing plants and hatcheries were not more likely to have salmonellosis, and individuals residing in Arkansas do not appear to be at increased risk of salmonellosis because of the poultry industry.

  7. Epidemiology of Ciguatera in Florida.

    PubMed

    Radke, Elizabeth G; Reich, Andrew; Morris, John Glenn

    2015-08-01

    Ciguatera is the most commonly reported marine food-borne illness worldwide. Because there is a biological plausibility that ciguatera may be impacted by long-term climate variability and Florida is on the northern border of the geographic distribution of ciguatera, it is important to update our understanding of its epidemiology in Florida. We performed an analysis of 291 reports in Florida from 2000 to 2011 and an e-mail survey of 5,352 recreational fishers to estimate incidence and underreporting and identify high risk demographic groups, fish types, and catch locations. Incidence was 5.6 per 100,000 adjusted for underreporting. Hispanics had the highest incidence rate (relative risk [RR] = 3.4) and were more likely to eat barracuda than non-Hispanics. The most common catch locations for ciguatera-causing fish were the Bahamas and Florida Keys. Cases caused by fish from northern Florida were infrequent. These results indicate that ciguatera incidence is higher than estimated from public health reports alone. There is little evidence that incidence or geographic range has increased because of increased seawater temperatures since earlier studies.

  8. Epidemiology of Ciguatera in Florida

    PubMed Central

    Radke, Elizabeth G.; Reich, Andrew; Morris, John Glenn

    2015-01-01

    Ciguatera is the most commonly reported marine food-borne illness worldwide. Because there is a biological plausibility that ciguatera may be impacted by long-term climate variability and Florida is on the northern border of the geographic distribution of ciguatera, it is important to update our understanding of its epidemiology in Florida. We performed an analysis of 291 reports in Florida from 2000 to 2011 and an e-mail survey of 5,352 recreational fishers to estimate incidence and underreporting and identify high risk demographic groups, fish types, and catch locations. Incidence was 5.6 per 100,000 adjusted for underreporting. Hispanics had the highest incidence rate (relative risk [RR] = 3.4) and were more likely to eat barracuda than non-Hispanics. The most common catch locations for ciguatera-causing fish were the Bahamas and Florida Keys. Cases caused by fish from northern Florida were infrequent. These results indicate that ciguatera incidence is higher than estimated from public health reports alone. There is little evidence that incidence or geographic range has increased because of increased seawater temperatures since earlier studies. PMID:26123957

  9. Epidemiology of the arterial stiffness.

    PubMed

    Breithaupt-Grögler, K; Belz, G G

    1999-06-01

    Aortic stiffening is as much an important risk factor in cardiovascular morbidity and mortality, as it serves as reliable surrogate marker for clinical endpoints like myocardial and cerebrovascular incidents. Elevated aortic stiffness induces high systolic blood pressure, augmented pulse pressure with increased ventricular afterload, reduced subendocardial blood flow and augmented pulsatile stress in the peripheral arteries. Factors with relevant impact on the epidemiology of arterial stiffness are widely spread. 3 major groups of parameters influencing the stiffness of the aorta and the large arteries have been studied and described up to now: (i) physiological properties like age, gender, body height, pressure, hormonal state, genetic factors; (ii) environmental factors like nutrition (fish-, salt-, garlic consumption), smoking, performance of sports and aerobic capacity; (iii) diseases like hypertension, hypercholesterolemia, diabetes, coronary heart disease, cerebrovascular disease, renal failure, Marfan-syndrome, growth hormone deficiency. Close association between several of these factors impedes analyzing them independently from each other. Age and blood pressure were found to be the most prominent predictors of arterial stiffness in normal as well as in disease populations. Physiological and environmental factors can modulate these effects of aging, diseases generally seem to amplify them.

  10. Epidemiology of cancer in children

    SciTech Connect

    Greenberg, R.S.; Shuster, J.L. Jr.

    1985-01-01

    The epidemiologic features of cancers among children have stimulated abundant descriptive and analytic investigation. The descriptive work has demonstrated consistent differences in the incidence rates of these cancers by anatomic site, age, race, and gender. It is clear that the various forms of cancer during childhood have distinctive patterns of occurrence. To a large extent, the characteristic population distributions of these diseases may represent differences in the underlying etiologic processes. Analytic studies of cancer during childhood have addressed possible genetic and environmental risk factors for these diseases. The demonstration of cancers induced by transplacental exposure to diethylstilbestrol has confirmed the speculation that the prenatal environment may influence subsequent carcinogenesis. Although possible leukemogenic effects of intrauterine diagnostic irradiation remain controversial, the issue may become unimportant clinically as prenatal irradiation is replaced by other diagnostic modalities (194). To date, studies of prenatal ultrasound have provided no evidence of an overall excess of subsequent malignancies. Postnatal exposure to high doses of irradiation is known to produce considerable excesses of leukemias and other cancers. At present, there are insufficient data available to reach a firm conclusion on the possible carcinogenic effects of exposure during childhood to low doses of irradiation, fringe magnetic fields, or chemicals.

  11. Trichloroethylene and cancer: epidemiologic evidence.

    PubMed Central

    Wartenberg, D; Reyner, D; Scott, C S

    2000-01-01

    Trichloroethylene is an organic chemical that has been used in dry cleaning, for metal degreasing, and as a solvent for oils and resins. It has been shown to cause liver and kidney cancer in experimental animals. This article reviews over 80 published papers and letters on the cancer epidemiology of people exposed to trichloroethylene. Evidence of excess cancer incidence among occupational cohorts with the most rigorous exposure assessment is found for kidney cancer (relative risk [RR] = 1.7, 95% confidence interval [CI] 1.1-2.7), liver cancer (RR = 1.9, 95% CI(1.0-3.4), and non-Hodgkin's lymphoma (RR = 1.5, 95% CI 0.9-2.3) as well as for cervical cancer, Hodgkin's disease, and multiple myeloma. However, since few studies isolate trichloroethylene exposure, results are likely confounded by exposure to other solvents and other risk factors. Although we believe that solvent exposure causes cancer in humans and that trichloroethylene likely is one of the active agents, we recommend further study to better specify the specific agents that confer this risk and to estimate the magnitude of that risk. PMID:10807550

  12. Epidemiology of Helicobacter pylori infection.

    PubMed

    Leja, Mārcis; Axon, Anthony; Brenner, Hermann

    2016-09-01

    This review of recent publications related to the epidemiology of Helicobacter pylori highlights the origin of the infection, its changing prevalence, transmission, and outcome. A number of studies have addressed the ancestor roots of the bacteria, and the first genomewide analysis of bacterial strains suggests that its coexistence with humans is more ancient than previously thought. As opposed to the generally declining prevalence of H. pylori (including China and Japan), in Sweden, the prevalence of atrophic gastritis in the young population has risen. The prevalence of the infection remains high in the indigenous populations of the Arctic regions, and reinfection rates are high. A high prevalence is permanently found in the Siberian regions of Russia as well. Several studies, some of which used multiplex serology, addressed prevalence of and risks associated with various H. pylori serotypes, thereby enabling more precise risk assessment. Transmission of H. pylori was discussed, specifically fecal-oral transmission and the use of well-water and other unpurified water. Finally, the long-term course of H. pylori infection was considered, with an estimated 89% of noncardia gastric cancer cases being attributable to the infection.

  13. Epidemiology of Helicobacter pylori infection.

    PubMed

    Eusebi, Leonardo H; Zagari, Rocco M; Bazzoli, Franco

    2014-09-01

    Medline and PubMed databases were searched on epidemiology of Helicobacter pylori for the period of April 2013-March 2014. Several studies have shown that the prevalence of H. pylori is still high in most countries. In north European and North American populations, about one-third of adults are still infected, whereas in south and east Europe, South America, and Asia, the prevalence of H. pylori is often higher than 50%. H. pylori remains highly prevalent in immigrants coming from countries with high prevalence of H. pylori. However, the lower prevalence of infection in the younger generations suggests a further decline of H. pylori prevalence in the coming decades. Low socioeconomic conditions in childhood are confirmed to be the most important risk factors for H. pylori infection. Although the way the infection is transmitted is still unclear, interpersonal transmission appears to be the main route. Finally, H. pylori recurrence after successful eradication can still occur, but seems to be an infrequent event.

  14. [Goiter epidemiology in South Tirol].

    PubMed

    Oberhofer, R; Ober, A; Seeber, A; Amor, H

    1992-10-02

    To ascertain the prevalence of goitre among schoolchildren in South Tyrol (uncontrolled voluntary iodine salt prophylaxis), the size of the thyroid gland was determined by palpation and ultrasound in 1,013 of 1,224 children, aged 6 to 14 years (547 boys, 466 girls), selected by statistically criteria. At the same time, to assess thyroid function, total and free fractions of T3 and T4, and TSH were measured, while iodine supply was determined by measuring urinary iodine. Stage Ia goitre was diagnosed by palpation in 157 children, stage Ib in 18 and stage II in two (goitre prevalence of 1.97% according to WHO criteria). Mean thyroid volume as determined by ultrasound was 4.26 (0.8-23.4) ml. As expected, it increased with age and body surface area: it was 2.55 +/- 0.49 ml in 6-year olds, 3.83 +/- 0.42 ml in 10-year olds and 6.42 +/- 0.69 ml in 14-year olds. Iodine excretion (143.8 [4.1-984.8] micrograms iodine/g creatinine) indicated adequate iodine supply to the tested subjects. South Tyrol is thus, according to WHO criteria, no longer an endemic goitre area. The voluntary use of iodinated cooking salt and changed food habits have probably effected this change in goitre epidemiology.

  15. Epidemiology of HBV subgenotypes D.

    PubMed

    Ozaras, Resat; Inanc Balkan, Ilker; Yemisen, Mucahit; Tabak, Fehmi

    2015-02-01

    The natural history of hepatitis B virus infection is not uniform and affected from several factors including, HBV genotype. Genotype D is a widely distributed genotype. Among genotype D, several subgenotypes differentiate epidemiologically and probably clinically. D1 is predominant in Middle East and North Africa, and characterized by early HBeAg seroconversion and low viral load. D2 is seen in Albania, Turkey, Brazil, western India, Lebanon, and Serbia. D3 was reported from Serbia, western India, and Indonesia. It is a predominant subgenotype in injection drug use-related acute HBV infections in Europe and Canada. D4 is relatively rare and reported from Haiti, Russia and Baltic region, Brazil, Kenya, Morocco and Rwanda. Subgenotype D5 seems to be common in Eastern India. D6 has been reported as a rare subgenotype from Indonesia, Kenya, Russia and Baltic region. D7 is the main genotype in Morocco and Tunisia. D8 and D9 are recently described subgenotypes and reported from Niger and India, respectively. Subgenotypes of genotype D may have clinical and/or viral differences. More subgenotype studies are required to conclude on subgenotype and its clinical/viral characteristics.

  16. Gene-Environment Research and Cancer Epidemiology

    Cancer.gov

    The Epidemiology and Genomics Research Program supports extramural research that investigates both genetic and environmental factors that may contribute to the etiology of cancer and/or impact cancer outcomes.

  17. Comprehensive Epidemiologic Data Resource (CEDR) (Poster)

    SciTech Connect

    Oak Ridge Institute for Science and Education

    2012-12-12

    This poster introduces the Comprehensive Epidemiologic Data Resource (CEDR), an electronic database with demographic, health outcome, and exposure information for over a million DOE nuclear plant and laboratory workers.

  18. Epidemiology of Meningococcal Disease in Northeastern Africa

    DTIC Science & Technology

    1987-01-01

    meningococcal meningits in Bamako, Mali: epidemiological features and analysis of vaccine efficacy, Lancet, ii, 315, 1982. 17. Kilpatrickt, MW. E., Maill. 1. A...r LIE) DTIC , . [iE LE CTE ili D PUBLICATION REPORT 1514 33/88 EPIDEMIOLOGY OF MENINGOCOCCAL DISEASE IN NORTHEASTERN AFRICA BY John E. Sippel, and...to the southern regions of the Sudan. Like the disease in the sub-Siaharan region, meningococcal meningitis in the Nile Valley is seaso- nal and most

  19. Courses in environmental and occupational epidemiology.

    PubMed

    Philipp, R; Kjellström, T

    1994-01-01

    The results of a survey are reported in which members of WHO's Global Environmental Epidemiology Network were asked for details of free-standing environmental and occupational epidemiology courses that were offered or planned for 1991-93 with tuition in English, French or Spanish and with places for persons living outside the countries concerned. Of the 126 courses on which information was received, 72 were open to health professionals from more than one discipline.

  20. Breast Cancer Epidemiology in Puerto Rico

    DTIC Science & Technology

    2008-06-30

    of the infrastructure for the study of the Epidemiology of Breast Cancer and the pilot case-control study as well as the initiation of the training...steps of the case-control studies are underway (identification of key personnel and initial training in the study protocol, obtaining local IRBs and...based study , epidemiology 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON

  1. Epidemiology of hepatitis E virus in Iran

    PubMed Central

    Taherkhani, Reza; Farshadpour, Fatemeh

    2016-01-01

    Iran is known as an endemic country for hepatitis E virus (HEV) infection, while there are variations in the epidemiology of HEV infection throughout the country. The available epidemiological studies in different regions of Iran show HEV seroprevalence of 1.1%-14.2% among general population, 4.5% -14.3% among blood donors, 6.1%-22.8% among injecting drug users, 6.3%-28.3% among hemodialysis patients, 1.6%-11.3% among patients infected with other hepatitis viruses, 27.5% among patients with chronic liver disease, 30.8% among kidney transplant recipient patients, and 10%-16.4% among human immunodeficiency virus-infected patients. These variations reflect differences in the status of public health and hygiene, risk factors, and routes of transmission in different regions and groups. Therefore, it is necessary to review the epidemiology of HEV infection to determine the most prevalent risk factors and routes of transmission, and to evaluate the effectiveness of preventive strategies employed in the public health services of the country. Moreover, the other epidemiological aspects of HEV, including the genotypic pattern, extra hepatic manifestations, and incidence of chronic infection need to be investigated among Iranian population to expand the current knowledge on the epidemiology of HEV and to clarify the real burden of HEV infection. Therefore, this review was performed to provide a general overview regarding the epidemiology of HEV in Iran. PMID:27298557

  2. Epidemiology and differential diagnosis of nasal polyps

    PubMed Central

    Chaaban, Mohamad R.; Walsh, Erika M.

    2013-01-01

    Background: Chronic rhinosinusitis (CRS) is one of the most common chronic medical conditions, with a significant impact on patient quality of life. CRS is broadly classified into two groups: CRS with nasal polyposis (CRSwNP) and CRS without NP (CRSsNP). Clinically, the major subtypes of CRSwNP may be divided into eosinophilic chronic rhinosinusitis (e.g., allergic fungal rhinosinusitis and aspirin-exacerbated respiratory disease [AERD]) and nasal polyps associated with neutrophilic inflammation (e.g., cystic fibrosis [CF]). CF is characterized by mutation of the gene encoding the CF transmembrane conductance regulator. Functional endoscopic sinus surgery is usually required for most NP patients with increased frequency in patients with AERD. This study provides a review of the epidemiology and major classification of CRSwNP. Methods: A review was performed of the literature regarding different subtypes of CRSwNP. Results: Many definitions of CRSwNP exist and estimates of prevalence vary. Conclusion: CRSwNP is a clinical syndrome with a heterogeneous inflammatory profile. Of the subtypes associated with eosinophilic inflammation, AERD remains the most recalcitrant to medical and surgical therapeutic interventions. PMID:24274222

  3. Epidemiology of Gallbladder Disease: Cholelithiasis and Cancer

    PubMed Central

    Stinton, Laura M.

    2012-01-01

    Diseases of the gallbladder are common and costly. The best epidemiological screening method to accurately determine point prevalence of gallstone disease is ultrasonography. Many risk factors for cholesterol gallstone formation are not modifiable such as ethnic background, increasing age, female gender and family history or genetics. Conversely, the modifiable risks for cholesterol gallstones are obesity, rapid weight loss and a sedentary lifestyle. The rising epidemic of obesity and the metabolic syndrome predicts an escalation of cholesterol gallstone frequency. Risk factors for biliary sludge include pregnancy, drugs like ceftiaxone, octreotide and thiazide diuretics, and total parenteral nutrition or fasting. Diseases like cirrhosis, chronic hemolysis and ileal Crohn's disease are risk factors for black pigment stones. Gallstone disease in childhood, once considered rare, has become increasingly recognized with similar risk factors as those in adults, particularly obesity. Gallbladder cancer is uncommon in developed countries. In the U.S., it accounts for only ~ 5,000 cases per year. Elsewhere, high incidence rates occur in North and South American Indians. Other than ethnicity and female gender, additional risk factors for gallbladder cancer include cholelithiasis, advancing age, chronic inflammatory conditions affecting the gallbladder, congenital biliary abnormalities, and diagnostic confusion over gallbladder polyps. PMID:22570746

  4. Epidemiological and Clinical Studies of Nutrition

    PubMed Central

    Gibson, Todd M.; Ferrucci, Leah M.; Tangrea, Joseph A.; Schatzkin, Arthur

    2010-01-01

    In this review, we briefly summarize some of the key developments in nutritional epidemiology and cancer over the past two decades with a focus on the strengths and limitations of study designs and dietary assessment methods. We present the evidence on dietary fat, meat, fiber, antioxidant nutrients, and calcium in relation to carcinogenesis from large cohort studies and randomized clinical trials (RCTs) and refer to the conclusions of the 2007 World Cancer Research Fund/American Institute for Cancer Research summary report. One prominent theme that emerged is the lack of concordance of results from RCTs and observational studies. There are multiple potential reasons for these discrepancies, including differences in study population, dose and timing of the exposure, adherence to an intervention, length of follow-up, and the primary endpoint. Therefore, null findings of RCTs do not necessarily indicate a lack of effect for the tested dietary factors on cancer risk, as some of these nutrients may have chemopreventive effects if given at the right time and in the right dose. It is likely that potential benefits from the diet are due to a combination of food constituents rather than single components acting in isolation. Future efforts need to recognize the integrative nature of dietary exposures and attempt to study nutrients in the larger context of the foods and diets in which they are consumed. PMID:20709210

  5. Critical issues in air pollution epidemiology.

    PubMed Central

    Lippmann, M; Lioy, P J

    1985-01-01

    The epidemiological studies which have had significant impact on the setting of National Ambient Air Quality Standards (NAAQSs) were performed more than twenty years ago. Most of the more recent studies have been seriously flawed in their design and/or execution because they neglected to account for important variables such as: pollutant exposures other than those from ambient air; the influence of personal activity on pollutant uptake; host responsiveness; and the separate contributions of recent transient peak exposures and long-term chronic exposures on the effects endpoints. For particulate pollutants, the influence of composition and size distribution has also received too little consideration. In order to address these deficiencies, research and methods development are needed on: indices for particulate exposures; identification of exposures relevant to the effects; improved indices of effects; acquisition of response data; identification of exposed populations; and identification of susceptible subgroups. Approaches to these needs are discussed, along with brief reviews of several recent studies that have focused on critical issues of concern, made the necessary efforts to characterize the relevant exposures of the populations being studied, and demonstrated human responses to ambient pollutants at current exposure levels. PMID:4085428

  6. Ribotyping of Pseudomonas aeruginosa: discriminatory power and usefulness as a tool for epidemiological studies.

    PubMed Central

    Blanc, D S; Siegrist, H H; Sahli, R; Francioli, P

    1993-01-01

    Restriction fragment length polymorphism of ribosomal DNA regions (ribotyping) of Pseudomonas aeruginosa was evaluated as a tool for epidemiological purposes. Fifty-five epidemiologically unrelated isolates from three geographic areas of Switzerland and 11 isolates obtained during an outbreak of P. aeruginosa infections in a burn unit were typed by this method. Typeability and reproducibility of the method reached 100%. With four selected restriction enzymes (BamHI, ClaI, EcoRI, and PstI), the 55 unrelated isolates could be classified into 33 ribotypes. To assess the value of this method for the interpretation of epidemiological data, we calculated an index of discrimination (ID) which takes into consideration both the number of types defined by the typing method and their relative frequencies. Our ribotyping system obtained a high ID of 0.958 with only four restriction enzymes, comparing well with other different typing schemes for which ID values could be calculated from published data. All clinical isolates of the outbreak belonged to the same ribotype, whereas environmental isolates, initially thought to be the source of the epidemic, belonged to a different ribotype. Thus, the typeability, reproducibility, and discriminatory power of our method as well as its value established in an epidemiological investigation were found to be appropriate for further epidemiological studies of P. aeruginosa. Images PMID:8093252

  7. [Epidemiology and laboratory diagnostics of legionellae].

    PubMed

    Szénási, Z; Endo, T; Yagita, K; Veréb, I; Nagy, E

    2001-05-20

    The severe pulmonary disease caused by the inhalation of the different Legionella species is called Legionella pneumonia, while the name of the pulmonary disease caused by the most common Legionella (L. pneumophila) is Legionnaires' disease. Another type of disease caused by legionellae is Pontiac fever with influenza-like symptoms. Legionella spp. are facultative intracellular parasites. They survive within both monocytes in the human organism and amebae in the environment. To prevent and control the occurrence of legionelloses, legionellae should be surveyed and detected in the environmental (water pipes, air-conditioning systems, cooling towers, respiratory equipments, etc.) and clinical (blood, bronchoalveolar lavage, sputum, abscess, etc.) samples. Laboratory diagnosis is complicated by the limitations of the available assays. Thus, it is proposed that the microbiological laboratory diagnosis should be based on the simultaneous application of at least three methods (culturing [on BCYE medium], followed by biochemical assays, serology, molecular biologic methods, such as polymerase chain reaction [PCR], direct demonstration [immunofluorescence microscopy], antigen determination are the most important ones) and on the simultaneous demonstration from three different samples (e.g. lower respiratory tract secretions, sputum, urine, blood culture, serum, moreover, water samples from all potential infectious sources, sediment of hot water tanks, as well as swab samples of faucets and shower heads). The advantage of PCR is that is gives reliable results in one day, in contrast to conventional culturing. However, its sensitivity can not be improved by increasing the sample volume, and neither can it give quantitative results nor can it produce strains for epidemiologic studies, contrary to the method of culturing. It is concluded that PCR and culturing do complement, but do not substitute each other.

  8. High heterogeneity in methods used for the laboratory confirmation of pertussis diagnosis among European countries, 2010: integration of epidemiological and laboratory surveillance must include standardisation of methodologies and quality assurance.

    PubMed

    He, Q; Barkoff, A M; Mertsola, J; Glismann, S; Bacci, S

    2012-08-09

    Despite extensive childhood immunisation, pertussis remains one of the world’s leading causes of vaccine preventable deaths. The current methods used for laboratory diagnosis of pertussis include bacterial culture, polymerase chain reaction (PCR) and enzyme linked immunosorbent assay (ELISA) serology. We conducted a questionnaire survey to identify variations in the laboratory methods and protocols used among participating countries included in the European surveillance network for vaccine-preventable diseases(EUVAC.NET). In February 2010, we performed the survey using a web-based questionnaire and sent it to the country experts of 25 European Union countries,and two European Economic Area (EEA) countries,Norway and Iceland. The questionnaire consisted of 37 questions which covered both general information on surveillance methods and detailed laboratory methods used. A descriptive analysis was performed.Questionnaires were answered by all 27 contacted countries. Nineteen countries had pertussis reference laboratories at the national level; their functions varied from performing diagnosis to providing technical advice for routine microbiology laboratories. Culture,PCR and serology were used in 17, 18 and 20 countries,respectively. For PCR, nine laboratories used insertion sequence IS481 as the target gene, which is present in multiple copies in the Bordetella pertussis genome and thus has a greater sensitivity over single copy targets, but has been proved not to be specific for B.pertussis. Antibodies directed against pertussis toxin(PT) are specific for B. pertussis infections. For ELISA serology, only 13 countries’ laboratories used purified PT as coating antigen and 10 included World Health Organization (WHO) or Food and Drug Administration (FDA) reference sera in their tests. This present survey shows that methods used for laboratory confirmation of pertussis differ widely among European countries and that there is a great heterogeneity of the reference

  9. Atrazine and Pregnancy Outcomes: A Systematic Review of Epidemiologic Evidence

    PubMed Central

    Goodman, Michael; Mandel, Jack S; DeSesso, John M; Scialli, Anthony R

    2014-01-01

    Atrazine (ATR) is a commonly used agricultural herbicide that has been the subject of epidemiologic studies assessing its relation to reproductive health problems. This review evaluates both the consistency and the quality of epidemiologic evidence testing the hypothesis that ATR exposure, at usually encountered levels, is a risk factor for birth defects, small for gestational age birth weight, prematurity, miscarriages, and problems of fetal growth and development. We followed the current methodological guidelines for systematic reviews by using two independent researchers to identify, retrieve, and evaluate the relevant epidemiologic literature on the relation of ATR to various adverse outcomes of birth and pregnancy. Each eligible paper was summarized with respect to its methods and results with particular attention to study design and exposure assessment, which have been cited as the main areas of weakness in ATR research. As a quantitative meta-analysis was not feasible, the study results were categorized qualitatively as positive, null, or mixed. The literature on ATR and pregnancy-related health outcomes is growing rapidly, but the quality of the data is poor with most papers using aggregate rather than individual-level information. Without good quality data, the results are difficult to assess; however, it is worth noting that none of the outcome categories demonstrated consistent positive associations across studies. Considering the poor quality of the data and the lack of robust findings across studies, conclusions about a causal link between ATR and adverse pregnancy outcomes are not warranted. PMID:24797711

  10. The Singapore Field Epidemiology Service: Insights Into Outbreak Management

    PubMed Central

    Seetoh, Theresa; Cutter, Jeffery

    2012-01-01

    Field epidemiology involves the implementation of quick and targeted public health interventions with the aid of epidemiological methods. In this article, we share our practical experiences in outbreak management and in safeguarding the population against novel diseases. Given that cities represent the financial nexuses of the global economy, global health security necessitates the safeguard of cities against epidemic diseases. Singapore's public health landscape has undergone a systemic and irreversible shift with global connectivity, rapid urbanization, ecological change, increased affluence, as well as shifting demographic patterns over the past two decades. Concomitantly, the threat of epidemics, ranging from severe acute respiratory syndrome and influenza A (H1N1) to the resurgence of vector-borne diseases as well as the rise of modern lifestyle-related outbreaks, have worsened difficulties in safeguarding public health amidst much elusiveness and unpredictability. One critical factor that has helped the country overcome these innate and man-made public health vulnerabilities is the development of a resilient field epidemiology service, which includes our enhancement of surveillance and response capacities for outbreak management, and investment in public health leadership. We offer herein the Singapore story as a case study in meeting the challenges of disease control in our modern built environment. PMID:23091652

  11. Colorectal Cancer Epidemiology in the Nurses’ Health Study

    PubMed Central

    Lee, Dong Hoon; Giovannucci, Edward L.

    2016-01-01

    Objectives. To review the contribution of the Nurses’ Health Study (NHS) to identifying risk and protective factors for colorectal adenomas and colorectal cancer (CRC). Methods. We performed a narrative review of the publications using the NHS between 1976 and 2016. Results. Existing epidemiological studies using the NHS have reported that red and processed meat, alcohol, smoking, and obesity were associated with an increased risk of CRC, whereas folate, calcium, vitamin D, aspirin, and physical activity were associated with decreased risk of CRC. Moreover, modifiable factors, such as physical activity, vitamin D, folate, insulin and insulin-like growth factor binding protein-1, and diet quality, were identified to be associated with survival among CRC patients. In recent years, molecular pathological epidemiological studies have been actively conducted and have shown refined results by molecular subtypes of CRC. Conclusions. The NHS has provided new insights into colorectal adenomas, CRC etiology, and pathogenic mechanisms. With its unique strengths, the NHS should continue to contribute to the field of CRC epidemiology and play a major role in public health. PMID:27459444

  12. The health impacts of semiconductor production: an epidemiologic review

    PubMed Central

    Kim, Myoung-Hee; Kim, Hyunjoo; Paek, Domyung

    2014-01-01

    Background: Despite concerns over the harmful health effects of semiconductor production, epidemiological studies have shown mixed results. Objectives: We aim to critically appraise epidemiologic studies to date, and to suggest future research and actions to protect workers in semiconductor industry. Methods: Epidemiologic studies were identified through electronic database searches, review of reference lists of relevant published works, and expert consultations, and were narratively reviewed. Results: Most evidence suggests reproductive risks from fabrication jobs, including spontaneous abortion (SAB), congenital malformation, and reduced fertility. Although chemicals have been suspected as causal agents, knowledge of the likely contribution(s) from specific exposures is still limited. Evidence of cancer risk seems to be equivocal. However, the available studies had serious limitations including healthy worker effects (HWEs), information bias, and insufficient power, all of which are associated with underestimation. Nevertheless, excess risks for non-Hodgkin's lymphoma (NHL), leukemia, brain tumor, and breast cancer were observed. Conclusions: Monitoring and innovative research based on international collaboration with a focus on sentinel events are required. PMID:24999845

  13. Doses for post-Chernobyl epidemiological studies: are they reliable?

    PubMed

    Drozdovitch, Vladimir; Chumak, Vadim; Kesminiene, Ausrele; Ostroumova, Evgenia; Bouville, André

    2016-09-01

    On 26 April 2016, thirty years will have elapsed since the occurrence of the Chernobyl accident, which has so far been the most severe in the history of the nuclear reactor industry. Numerous epidemiological studies were conducted to evaluate the possible health consequences of the accident. Since the credibility of the association between the radiation exposure and health outcome is highly dependent on the adequacy of the dosimetric quantities used in these studies, this paper makes an effort to overview the methods used to estimate individual doses and the associated uncertainties in the main analytical epidemiological studies (i.e. cohort or case-control) related to the Chernobyl accident. Based on the thorough analysis and comparison with other radiation studies, the authors conclude that individual doses for the Chernobyl analytical epidemiological studies have been calculated with a relatively high degree of reliability and well-characterized uncertainties, and that they compare favorably with many other non-Chernobyl studies. The major strengths of the Chernobyl studies are: (1) they are grounded on a large number of measurements, either performed on humans or made in the environment; and (2) extensive effort has been invested to evaluate the uncertainties associated with the dose estimates. Nevertheless, gaps in the methodology are identified and suggestions for the possible improvement of the current dose estimates are made.

  14. The Role of Epidemiology in Disaster Response Policy Development

    PubMed Central

    Thorpe, Lorna E; Assari, Shervin; Deppen, Stephen; Glied, Sherry; Lurie, Nicole; Mauer, Matthew P; Mays, Vickie M.; Trapido, Edward

    2015-01-01

    Purpose Disasters expose the general population and responders to a range of potential contaminants and stressors which may harm physical and mental health. This article addresses the role of epidemiology in informing policies after a disaster to mitigate ongoing exposures, provide care and compensation, and improve preparedness for future disasters. Methods The World Trade Center (WTC) disaster response is used as a case study. We examine how epidemiologic evidence was used to shape post-disaster policy and identify important gaps in early research. Results In the wake of WTC attacks, epidemiologic research played a key role in identifying and characterizing affected populations, assessing environmental exposures, quantifying physical and mental health impacts, and producing evidence to ascribe causation. However, most studies suffered from methodological challenges, including delays, selection biases, poor exposure measurement, and nonstandardized outcomes. Gaps included measuring unmet health needs and financing coverage, as well as coordination across longitudinal cohorts of studies for rare conditions with long latency, such as cancer. Conclusions Epidemiologists can increase their impact on evidence-based policymaking by ensuring core mechanisms are in place prior to a disaster to mount monitoring of responders and other affected populations, improve early exposure assessment efforts, identify critical gaps in scientific knowledge, and coordinate communication of scientific findings to policymakers and the public. PMID:25150446

  15. Operational definitions of asthma in recent epidemiological studies are inconsistent

    PubMed Central

    2014-01-01

    Objective The best combination of questions to define asthma in epidemiological asthma studies is not known. We summarized the operational definitions of asthma used in prevalence studies and empirically assess how asthma prevalence estimates vary depending on the definition used. Methods We searched the Thomson Reuters ISI Web of knowledge and included (1) cross-sectional studies (2) on asthma prevalence (3) conducted in the general population and (4) containing an explicit definition of asthma. The search was limited to the 100 most-cited papers or published since January 2010. For each paper, we recorded the asthma definition used and other variables. Then we applied the definitions to the data of the Portuguese National Asthma survey (INAsma) and of the 2005–2006 National Health and Nutrition Examination Survey (NHANES) computing asthma prevalence estimates for the different definitions. Results Of 1738 papers retrieved, 117 were included for analysis. Lifetime asthma, diagnosed asthma and current asthma were defined in 8, 12 and 29 different ways, respectively. By applying definitions of current asthma on INAsma and NHANES data, the prevalence ranged between 5.3%-24.4% and 1.1%-17.2%, respectively. Conclusions There is considerable heterogeneity in the definitions of asthma used in epidemiological studies leading to highly variable estimates of asthma prevalence. Studies to inform a standardized operational definition are needed. Meanwhile, we propose a set of questions to be reported when defining asthma in epidemiological studies. PMID:25136441

  16. Visions for the 20th International Epidemiological Association's World Congress of Epidemiology (WCE 2014).

    PubMed

    Monsour, B B; Johnston, J M; Hennessy, T W; Schmidt, M I; Krieger, N

    2012-03-01

    During August 17th-21st, 2014, the University of Alaska Anchorage, along with other local, state, and federal agencies throughout Alaska, will host the 20(th) International Epidemiological Association's (IEA) World Congress of Epidemiology (WCE 2014). The theme for this Congress is "Global Epidemiology in a Changing Environment: The Circumpolar Perspective." The changing environment includes the full range of environments that shape population health and health inequities from the physical to the social and economic. Our circumpolar perspective on these environments includes views on how political systems, work, immigration, Indigenous status, and gender relations and sexuality affect the global world and the health of its people. Suggestions and insights from the 3(rd) North American Congress of Epidemiology (2011) and the first-ever joint regional workshop co-organized by the IEA North American Region and the IEA Latin American and Caribbean Region held at the 19(th) IEA World Congress of Epidemiology (2011) have helped direct the focus for WCE 2014. Since the Arctic regions are feeling the effects of climate change first, we believe focusing on the emerging data on the health impacts of climate change throughout the world will be an important topic for this Congress. This will include a broad range of more traditional epidemiology areas such as infectious disease epidemiology, environmental epidemiology, health disparities, and surveillance and emergency preparedness. Addressing health inequities and promoting health equity is likewise a key concern of the Congress. This Congress will also host presentations on injury epidemiology, occupational health, infectious diseases, chronic diseases, maternal and child health, surveillance and field epidemiology, mental health, violence (from self-directed, e.g., suicide, to interpersonal to structural), psychoactive substance use (including tobacco), and measures of subjective health. Attention will be given to

  17. Breast Cancer: Epidemiology and Etiology.

    PubMed

    Tao, ZiQi; Shi, Aimin; Lu, Cuntao; Song, Tao; Zhang, Zhengguo; Zhao, Jing

    2015-06-01

    Breast cancer, the most frequently occurring cancer in women, is a major public health problem, with 1,384,155 estimated new cases worldwide with nearly 459,000 related deaths. Breast cancer is highly heterogeneous in its pathological characteristics, some cases showing slow growth with excellent prognosis, while others being aggressive tumors. Current predictions and statistics suggest that both worldwide incidence of breast cancer and related mortality are on the rise. According to 2012 GLOBOCAN statistics, nearly 1.7 million women were diagnosed with breast cancer with 522,000 related deaths-an increase in breast cancer incidence and related mortality by nearly 18 % from 2008. According to American Cancer Society, one in eight women in the United States will develop breast cancer in her lifetime. It has been predicted that the worldwide incidence of female breast cancer will reach approximately 3.2 million new cases per year by 2050. These numbers reflect the magnitude of breast cancer incidence, its effect on society worldwide and the need for urgency for preventive and treatment measures. While technological advances in medical sciences and health care have made it possible to detect the disease early and to start the treatment early on to prevent the progress of the disease into a metastatic state, there are several unanswered questions with regard to the molecular mechanisms that underlie the aggressiveness of certain forms of this disease. Epidemiological studies suggest that addressing socio economical issues is utmost important, so that all women have equal access to medical care from screening to advanced treatment, and only such decisive action can help reduce the worldwide burden of breast cancer.

  18. [Yellow fever epidemiology in Brazil].

    PubMed

    Mondet, B

    2001-08-01

    We have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in Brazil from 1954 to 1972 and especially from 1973 to 1999. This study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. The endemic area is located within the Amazon basin; here cases are scattered and generally limited in number. However, there are also "foci of endemic emergence" within this area, where cases are less rare, although occurrence remains irregular. The epidemic area is for the most part situated outside the Amazon basin, to the north east and particularly to the south. It has been divided into two parts according to whether the occurrence of yellow fever is cyclic or sporadic. The epidemics, which are all sylvatic, follow either a circular path (in the forest area) or a linear path (in forest-galleries of the savannah area). The study of the development of the 3 main epidemics (1972-74; 1979-82; 1986-92) in the cyclic emergence area showed that, on each occasion, the yellow fever virus appeared at a particularly active outbreak site located in the "serra dos Carajás", and from there, it followed the courses of the Tocantins and Araguaia rivers upstream, moving southwards during the "pre-epidemic phase" which may be visible due to the occurrence of a few cases, or may remain invisible. Subsequently the virus reached the emergence area, where it appeared in the form of epidemics. In this zone, it also followed privileged south-western pathways, moving from one hydraulic basin to another along the upstream courses of the rivers. Almost exactly the same pathways have been identified for each of the 3 epidemics studied. The distances travelled by the virus over a period of one year--when it goes rapidly--can reach several hundred kilometers. On the other hand, it may be stationary for a period of one or two consecutive years, occasionally three, remaining

  19. Integrating remote sensing and spatially explicit epidemiological modeling

    NASA Astrophysics Data System (ADS)

    Finger, Flavio; Knox, Allyn; Bertuzzo, Enrico; Mari, Lorenzo; Bompangue, Didier; Gatto, Marino; Rinaldo, Andrea

    2015-04-01

    Spatially explicit epidemiological models are a crucial tool for the prediction of epidemiological patterns in time and space as well as for the allocation of health care resources. In addition they can provide valuable information about epidemiological processes and allow for the identification of environmental drivers of the disease spread. Most epidemiological models rely on environmental data as inputs. They can either be measured in the field by the means of conventional instruments or using remote sensing techniques to measure suitable proxies of the variables of interest. The later benefit from several advantages over conventional methods, including data availability, which can be an issue especially in developing, and spatial as well as temporal resolution of the data, which is particularly crucial for spatially explicit models. Here we present the case study of a spatially explicit, semi-mechanistic model applied to recurring cholera outbreaks in the Lake Kivu area (Democratic Republic of the Congo). The model describes the cholera incidence in eight health zones on the shore of the lake. Remotely sensed datasets of chlorophyll a concentration in the lake, precipitation and indices of global climate anomalies are used as environmental drivers. Human mobility and its effect on the disease spread is also taken into account. Several model configurations are tested on a data set of reported cases. The best models, accounting for different environmental drivers, and selected using the Akaike information criterion, are formally compared via cross validation. The best performing model accounts for seasonality, El Niño Southern Oscillation, precipitation and human mobility.

  20. History, Epidemiology, and Clinical Manifestations of Zika: A Systematic Review

    PubMed Central

    Barreto, Florisneide; da Glória Teixeira, Maria; da Conceição N. Costa, Maria; Rodrigues, Laura C.

    2016-01-01

    Objectives. To describe salient epidemiological characteristics of Zika virus outbreaks across the world and to examine the clinical presentations, complications, and atypical manifestations related to their occurrence in recent history. Methods. We conducted a systematic review of the literature by searching through MEDLINE, Embase, and Global Health Library, as well as the epidemiological bulletins and alerts from the World Health Organization, the Pan American Health Organization, and the European Centre for Disease Prevention and Control over the period 1954 to 2016. Results. The search yielded 547 records. We retained 333 for further analysis, to which we added 11 epidemiological bulletins from various sources. Of these, we systematically reviewed 52 articles and reports, revealing some epidemiological features and patterns of spread of the Zika virus worldwide, as well as pathological outcomes suspected to be linked to Zika outbreaks. Neurologic disorders among zika patients were similar in Brazil and French Polynesia but a causal link is not established. Incidence of zika infection in pregnant women is not known. In Brazil, during the zika outbreak the incidence of microcephaly increased more than 20 times. Among 35 infants with microcephaly, born from women suspected to have Zika infection during pregnancy in northeast Brazil, 74% of the mothers reported rash during the first and second trimester. Conclusions. On February 1, 2016, The World Health Organization declared the ongoing Zika crisis an emergency and that, although not yet scientifically proven, the link between the virus and growing numbers of microcephaly cases was “strongly suspected.” However, the causal relationship between zika and microcephaly is not universally accepted. Public Health Implications. The current situation with regard to Zika is not encouraging, because there is no vaccine, no treatment, and no good serological test, and vector control remains a challenge. PMID:26959260

  1. Epidemiologic research topics in Germany: a keyword network analysis of 2014 DGEpi conference presentations.

    PubMed

    Peter, Raphael Simon; Brehme, Torben; Völzke, Henry; Muche, Rainer; Rothenbacher, Dietrich; Büchele, Gisela

    2016-06-01

    Knowledge of epidemiologic research topics as well as trends is useful for scientific societies, researchers and funding agencies. In recent years researchers recognized the usefulness of keyword network analysis for visualizing and analyzing scientific research topics. Therefore, we applied keyword network analysis to present an overview of current epidemiologic research topics in Germany. Accepted submissions to the 9th annual congress of the German Society for Epidemiology (DGEpi) in 2014 were used as data source. Submitters had to choose one of 19 subject areas, and were ask to provide a title, structured abstract, names of authors along with their affiliations, and a list of freely selectable keywords. Keywords had been provided for 262 (82 %) submissions, 1030 keywords in total. Overall the most common keywords were: "migration" (18 times), "prevention" (15 times), followed by "children", "cohort study", "physical activity", and "secondary data analysis" (11 times each). Some keywords showed a certain concentration under one specific subject area, e.g. "migration" with 8 of 18 in social epidemiology or "breast cancer" with 4 of 7 in cancer epidemiology. While others like "physical activity" were equally distributed over multiple subject areas (cardiovascular & metabolic diseases, ageing, methods, paediatrics, prevention & health service research). This keyword network analysis demonstrated the high diversity of epidemiologic research topics with a large number of distinct keywords as presented at the annual conference of the DGEpi.

  2. The contribution of molecular epidemiology to the understanding and control of viral diseases of salmonid aquaculture.

    PubMed

    Snow, Michael

    2011-04-05

    and analyse knowledge from a range of more traditional information sources. The development of methods to systematically record and share such epidemiologically important information thus represents a major challenge for fish health professionals in making the best future use of molecular data in supporting fish health policy and disease control.

  3. Epidemiology and statistics at the Nordic School of Public Health: Teaching and research 1979-2014.

    PubMed

    Eriksson, Bo

    2015-08-01

    The Nordic School of Public Health (NHV) was jointly founded in 1953 by the Nordic countries. Until 1979, the school provided ad hoc courses on public health topics, using external teachers drawn mainly from the Nordic countries. At the time, the permanent staff of the school was small. In 1979, it began a Master's degree programme and a few academic positions were established and filled, to support these courses. The programme included four main areas: Epidemiology, Social Medicine, Environmental Health and Health Services Administration. Epidemiology was compulsory in all Master of Public Health (MPH) exams, but there were a handful of optional courses that could be substituted for the other subjects.This paper tells the story of Epidemiology at NHV from about 1980, up until closure of the school in 2014. The original MPH model ran until 1995. Nursing Science entered NHV from about 1985 and worked mainly with qualitative research that often focused on individual patients. The new methods attracted nurses, midwives, psychologists and other groups that previously had been less represented in NHV. Being quantitative and population oriented, Epidemiology lost its unique position as a mandatory subject for the MPH examination. In addition the 'New Public Health' proposed by the World Health Organisation (WHO) that advocated health promotion and the philosophy of salutogenesis became a challenge for the programme in epidemiology: pathogenesis no longer was of primary interest. From 1995, the MPH format changed repeatedly and a DrPH programme was begun. For the last 8 years of its existence, NHV offered a reasonably comprehensive, basic course in Epidemiology.Throughout the years, epidemiology training and research at NHV were very traditional. In being a relatively free institution in terms of academic choices, NHV should have contributed to the development and innovation of epidemiology in public health. For several reasons, this did not happen.

  4. [Methodology of assessing and evaluating public health risk in legal regulation of sanitary epidemiologic well-being of population].

    PubMed

    Kuz'min, S V; Gurvich, V B; Dikonskaya, O V; Malykh, O L; Yarushin, S V

    2016-01-01

    The authors describe method to assess and manage risk for public health in system of legal regulation of sanitary epidemiologic well-being of population. Scheme of assessment and management of occupational risks is presented.

  5. Missing data and multiple imputation in clinical epidemiological research.

    PubMed

    Pedersen, Alma B; Mikkelsen, Ellen M; Cronin-Fenton, Deirdre; Kristensen, Nickolaj R; Pham, Tra My; Pedersen, Lars; Petersen, Irene

    2017-01-01

    Missing data are ubiquitous in clinical epidemiological research. Individuals with missing data may differ from those with no missing data in terms of the outcome of interest and prognosis in general. Missing data are often categorized into the following three types: missing completely at random (MCAR), missing at random (MAR), and missing not at random (MNAR). In clinical epidemiological research, missing data are seldom MCAR. Missing data can constitute considerable challenges in the analyses and interpretation of results and can potentially weaken the validity of results and conclusions. A number of methods have been developed for dealing with missing data. These include complete-case analyses, missing indicator method, single value imputation, and sensitivity analyses incorporating worst-case and best-case scenarios. If applied under the MCAR assumption, some of these methods can provide unbiased but often less precise estimates. Multiple imputation is an alternative method to deal with missing data, which accounts for the uncertainty associated with missing data. Multiple imputation is implemented in most statistical software under the MAR assumption and provides unbiased and valid estimates of associations based on information from the available data. The method affects not only the coefficient estimates for variables with missing data but also the estimates for other variables with no missing data.

  6. Missing data and multiple imputation in clinical epidemiological research

    PubMed Central

    Pedersen, Alma B; Mikkelsen, Ellen M; Cronin-Fenton, Deirdre; Kristensen, Nickolaj R; Pham, Tra My; Pedersen, Lars; Petersen, Irene

    2017-01-01

    Missing data are ubiquitous in clinical epidemiological research. Individuals with missing data may differ from those with no missing data in terms of the outcome of interest and prognosis in general. Missing data are often categorized into the following three types: missing completely at random (MCAR), missing at random (MAR), and missing not at random (MNAR). In clinical epidemiological research, missing data are seldom MCAR. Missing data can constitute considerable challenges in the analyses and interpretation of results and can potentially weaken the validity of results and conclusions. A number of methods have been developed for dealing with missing data. These include complete-case analyses, missing indicator method, single value imputation, and sensitivity analyses incorporating worst-case and best-case scenarios. If applied under the MCAR assumption, some of these methods can provide unbiased but often less precise estimates. Multiple imputation is an alternative method to deal with missing data, which accounts for the uncertainty associated with missing data. Multiple imputation is implemented in most statistical software under the MAR assumption and provides unbiased and valid estimates of associations based on information from the available data. The method affects not only the coefficient estimates for variables with missing data but also the estimates for other variables with no missing data. PMID:28352203

  7. Adjustment Disorder: epidemiology, diagnosis and treatment

    PubMed Central

    2009-01-01

    Background Adjustment Disorder is a condition strongly tied to acute and chronic stress. Despite clinical suggestion of a large prevalence in the general population and the high frequency of its diagnosis in the clinical settings, there has been relatively little research reported and, consequently, very few hints about its treatments. Methods the authors gathered old and current information on the epidemiology, clinical features, comorbidity, treatment and outcome of adjustment disorder by a systematic review of essays published on PUBMED. Results After a first glance at its historical definition and its definition in the DSM and ICD systems, the problem of distinguishing AD from other mood and anxiety disorders, the difficulty in the definition of stress and the implied concept of 'vulnerability' are considered. Comorbidity of AD with other conditions, and outcome of AD are then analyzed. This review also highlights recent data about trends in the use of antidepressant drugs, evidence on their efficacy and the use of psychotherapies. Conclusion AD is a very common diagnosis in clinical practice, but we still lack data about its rightful clinical entity. This may be caused by a difficulty in facing, with a purely descriptive methods, a "pathogenic label", based on a stressful event, for which a subjective impact has to be considered. We lack efficacy surveys concerning treatment. The use of psychotropic drugs such as antidepressants, in AD with anxious or depressed mood is not properly supported and should be avoided, while the usefulness of psychotherapies is more solidly supported by clinical evidence. To better determine the correct course of therapy, randomized-controlled trials, even for the combined use of drugs and psychotherapies, are needed vitally, especially for the resistant forms of AD. PMID:19558652

  8. Gallbladder cancer: epidemiology and outcome

    PubMed Central

    Hundal, Rajveer; Shaffer, Eldon A

    2014-01-01

    Gallbladder cancer, though generally considered rare, is the most common malignancy of the biliary tract, accounting for 80%–95% of biliary tract cancers. An early diagnosis is essential as this malignancy progresses silently with a late diagnosis, often proving fatal. Its carcinogenesis follows a progression through a metaplasia–dysplasia–carcinoma sequence. This comprehensive review focuses on and explores the risks, management, and outcomes for primary gallbladder carcinoma. Epidemiological studies have identified striking geographic and ethnic disparities – inordinately high occurrence in American Indians, elevated in Southeast Asia, yet quite low elsewhere in the Americas and the world. Age, female sex, congenital biliary tract anomalies, and a genetic predisposition represent important risk factors that are immutable. Environmental triggers play a critical role in eliciting cancer developing in the gallbladder, best exemplified by cholelithiasis and chronic inflammation from biliary tract and parasitic infections. Mortality rates closely follow incidence; those countries with the highest prevalence of gallstones experience the greatest mortality from gallbladder cancer. Vague symptoms often delay the diagnosis of gallbladder cancer, contributing to its overall progression and poor outcome. Surgery represents the only potential for cure. Some individuals are fortunate to be incidentally found to have gallbladder cancer at the time of cholecystectomy being performed for cholelithiasis. Such an early diagnosis is imperative as a late presentation connotes advanced staging, nodal involvement, and possible recurrence following attempted resection. Overall mean survival is a mere 6 months, while 5-year survival rate is only 5%. The dismal prognosis, in part, relates to the gallbladder lacking a serosal layer adjacent to the liver, enabling hepatic invasion and metastatic progression. Improved imaging modalities are helping to diagnose patients at an earlier

  9. Epidemiology of human African trypanosomiasis

    PubMed Central

    Franco, Jose R; Simarro, Pere P; Diarra, Abdoulaye; Jannin, Jean G

    2014-01-01

    Human African trypanosomiasis (HAT), or sleeping sickness, is caused by Trypanosoma brucei gambiense, which is a chronic form of the disease present in western and central Africa, and by Trypanosoma brucei rhodesiense, which is an acute disease located in eastern and southern Africa. The rhodesiense form is a zoonosis, with the occasional infection of humans, but in the gambiense form, the human being is regarded as the main reservoir that plays a key role in the transmission cycle of the disease. The gambiense form currently assumes that 98% of the cases are declared; the Democratic Republic of the Congo is the most affected country, with more than 75% of the gambiense cases declared. The epidemiology of the disease is mediated by the interaction of the parasite (trypanosome) with the vectors (tsetse flies), as well as with the human and animal hosts within a particular environment. Related to these interactions, the disease is confined in spatially limited areas called “foci”, which are located in Sub-Saharan Africa, mainly in remote rural areas. The risk of contracting HAT is, therefore, determined by the possibility of contact of a human being with an infected tsetse fly. Epidemics of HAT were described at the beginning of the 20th century; intensive activities have been set up to confront the disease, and it was under control in the 1960s, with fewer than 5,000 cases reported in the whole continent. The disease resurged at the end of the 1990s, but renewed efforts from endemic countries, cooperation agencies, and nongovernmental organizations led by the World Health Organization succeeded to raise awareness and resources, while reinforcing national programs, reversing the trend of the cases reported, and bringing the disease under control again. In this context, sustainable elimination of the gambiense HAT, defined as the interruption of the transmission of the disease, was considered as a feasible target for 2030. Since rhodesiense HAT is a zoonosis

  10. [Scientific, practical and educational aspects of clinical epidemiology].

    PubMed

    Briko, N I

    2012-01-01

    This article defines clinical epidemiology and describes its goal and objectives. The author claims that clinical epidemiology is a section of epidemiology which underlies the development of evidence-based standards for diagnostics, treatment and prevention and helps to select the appropriate algorithm for each clinical case. The study provides a comprehensive overview of the relationship between clinical epidemiology and evidence-based medicine. Epidemiological research is shown to be methodological basis of clinical epidemiology and evidence-based medicine with randomized controlled trials being the "gold standard" for obtaining reliable data. The key stages in the history of clinical epidemiology are discussed and further development of clinical epidemiology and the integration of courses on clinical epidemiology in education is outlined for progress in medical research and health care practice.

  11. The origins of American psychiatric epidemiology.

    PubMed Central

    Grob, G N

    1985-01-01

    Psychiatric epidemiology developed relatively late (as compared with epidemiology generally). Nineteenth century psychiatrists, although avid collectors of statistics, did not use such data in any systematic manner. The impetus for the creation of an epidemiology of mental illness came from the work of late nineteenth century social scientists concerned with understanding individual and social behavior and applying their findings to social problems. Initially they helped to create the modern census, which represented a radical faith that quantitative research, when merged with administrative rationality, could replace politics. During and after the 1920s, the demographic analysis of the institutionalized mentally ill population expanded sharply; by the late 1930s and 1940s psychiatric epidemiologists had begun to study the role of socioenvironmental variables and the incidence of mental illness in the community. Twentieth century psychiatric epidemiologists, however, faced a severe intellectual problem; their work rested on a descriptive rather than an etiological nosology. Consequently, the results of epidemiological studies in psychiatry often differed precisely because of variations in the design of studies and classification systems as well as the subjective observations of the investigators themselves. The ensuing disagreements among those involved in the epidemiologic study of mental illness were a natural consequence. Images p230-a p231-a p231-b p232-a p233-a p233-b p234-a PMID:3883818

  12. Evolution of environmental epidemiologic risk assessment

    SciTech Connect

    Anderson, H.A.

    1985-10-01

    Epidemiology has historically played an important role in the recognition of causes for diseases affecting the health of the public. Initially, epidemiology was concerned with infectious diseases. Later it became involved in metabolic and dietary deficiency diseases. Most recently, epidemiology has addressed the question of the public health effects of chemicals from production facilities, accidental spills, and chemical waste disposal sites. Concurrent improvements in the sensitivity of chemical analyses have enabled the identification of chemicals arising from waste disposal sites in the soil, air, drinking water, and food supplies of neighboring residential areas, albeit usually at very low concentrations. This knowledge has created great concerns among the affected populations and their public health agencies. The responsibility for interpreting the potential severity of the health effects of these environmental contaminants has fallen to those scientists experienced in epidemiology. This has led to a subdiscipline, reactive epidemiology, which describes investigations focused on specific events, usually under emotion-laden circumstances, rather than scientific merit. The reactive epidemiologist is rigidly constrained as to the size, timing, and location of the study. There is a strong requirement for public communication skills. New data bases are needed including ''sentinel'' diseases that are linked to exposure to chemicals, records of land use, and residency data for the population at risk.

  13. Epidemiology and causation: a realist view.

    PubMed Central

    Renton, A

    1994-01-01

    In this paper the controversy over how to decide whether associations between factors and diseases are causal is placed within a description of the public health and scientific relevance of epidemiology. It is argued that the rise in popularity of the Popperian view of science, together with a perception of the aims of epidemiology as being to identify appropriate public health interventions, have focussed this debate on unresolved questions of inferential logic, leaving largely unanalysed the notions of causation and of disease at the ontological level. A realist ontology of causation of disease and pathogenesis is constructed within the framework of "scientific materialism", and is shown to provide a coherent basis from which to decide causes and to deal with problems of confounding and interaction in epidemiological research. It is argued that a realist analysis identifies a richer role for epidemiology as an integral part of an ontologically unified medical science. It is this unified medical science as a whole rather than epidemiological observation or experiment which decides causes and, in turn, provides a key element to the foundations of rational public health decision making. PMID:8138775

  14. Hierarchical regression for epidemiologic analyses of multiple exposures

    SciTech Connect

    Greenland, S.

    1994-11-01

    Many epidemiologic investigations are designed to study the effects of multiple exposures. Most of these studies are analyzed either by fitting a risk-regression model with all exposures forced in the model, or by using a preliminary-testing algorithm, such as stepwise regression, to produce a smaller model. Research indicates that hierarchical modeling methods can outperform these conventional approaches. These methods are reviewed and compared to two hierarchical methods, empirical-Bayes regression and a variant here called {open_quotes}semi-Bayes{close_quotes} regression, to full-model maximum likelihood and to model reduction by preliminary testing. The performance of the methods in a problem of predicting neonatal-mortality rates are compared. Based on the literature to date, it is suggested that hierarchical methods should become part of the standard approaches to multiple-exposure studies. 35 refs., 1 fig., 1 tab.

  15. Clinical research: up from 'clinical epidemiology'.

    PubMed

    Miettinen, Olli S; Bachmann, Lucas M; Steurer, Johann

    2009-12-01

    Clinical research must be understood to be the foundation of scientific medicine of the clinical type. But the essence of scientific clinical medicine remains a matter of profound confusion, even in clinical academia, and so does the essence of clinical research. The confusion now revolves, principally, around 'clinical epidemiology'. We address clinical research in the meaning of quintessentially 'applied' clinical research, which we take to be the foundation of the scientific knowledge base of clinical medicine, of gnosis (dia-, etio-, pro-) in it. More specifically, we address the essence, priorities, and status quo of this research - and argue that the requisite theory of this is not a matter of 'clinical epidemiology' but of theory of clinical research endogenous to clinical (rather than epidemiological) academia.

  16. Epidemiology of Injury in Gaelic Handball.

    PubMed

    O'Connor, S; Downey, M; Moran, K

    2016-03-10

    The initial step in developing injury prevention strategies is to establish the epidemiology of injury. However there has been no published research on injury in Gaelic handball. This study describes the epidemiology of injury in 75 Gaelic handball players utilising a retrospective questionnaire. 88% of participants reported one or more injuries. Injuries to the upper limb were prevalent (52.9%), followed by the lower limb (30.3%). The shoulder (17.6%), finger (10.5%) and ankle (9.8%) were the primary sites of injury. Injuries occurred most frequently in December (9.7%), January (9.7%), February (9.7%) and November (8.7%). Injuries predominantly occurred during games (82.4%). Injuries were primarily severe (54.7%), with 14.6% of participants admitted to hospital due to injury. Given that this is the only study on Gaelic handball to date, prospective epidemiological studies and further research on injury prevention strategies are necessary.

  17. Contagion: epidemiological models and financial crises.

    PubMed

    Peckham, Robert

    2014-03-01

    Since the 1990s, economists have drawn on the epidemiology of emerging infectious diseases to explain the diffusion of shock through an increasingly complex financial system. The successful coordination of public health responses to disease threats, and in particular the epidemiological modelling underpinning infection control, has influenced economists' understanding of the risks posed to the stability of the financial system by 'contagion'. While the exportation of analytic models and frames of reference can be fruitful, reinvigorating the destination domain, such analogizing can have a distorting effect. There are differences between biological and financial systems. Moreover, the migration of highly context-specific epidemiological models may undermine the basis of the analogy. Finally, there may be repercussions for the efficacy of public health in the way that its aims are misconstrued in financial analyses.

  18. Genesis of Preeclampsia: An Epidemiological Approach

    PubMed Central

    Salvador-Moysén, Jaime; Martínez-López, Yolanda; Ramírez-Aranda, José M.; Aguilar-Durán, Marisela; Terrones-González, Alberto

    2012-01-01

    There are analyzed some of the main aspects related to the causality of preeclampsia, privileging two types of models: the clinic model and the epidemiologic model, first one represented by the hypothesis of the reduced placental perfusion and the second one considering the epidemiologic findings related to the high levels of psychosocial stress and its association with preeclampsia. It is reasoned out the relevance of raising the causality of the disease from an interdisciplinary perspective, integrating the valuable information generated from both types, clinical and epidemiologic, and finally a tentative explanatory model of preeclampsia is proposed, the subclinical and sociocultural aspects that predispose and trigger the disease are emphasized making aspects to stand out: the importance of reduced placental perfusion as an indicator of individual risk, and the high levels of physiological stress, as a result of the unfavorable conditions of the psychosocial surroundings (indicator of population risk) of the pregnant women. PMID:22462008

  19. Some applications of categorical data analysis to epidemiological studies.

    PubMed

    Grizzle, J E; Koch, G G

    1979-10-01

    Several examples of categorized data from epidemiological studies are analyzed to illustrate that more informative analysis than tests of independence can be performed by fitting models. All of the analyses fit into a unified conceptual framework that can be performed by weighted least squares. The methods presented show how to calculate point estimate of parameters, asymptotic variances, and asymptotically valid chi 2 tests. The examples presented are analysis of relative risks estimated from several 2 x 2 tables, analysis of selected features of life tables, construction of synthetic life tables from cross-sectional studies, and analysis of dose-response curves.

  20. Epidemiology of Uterine Fibroids – From Menarche to Menopause

    PubMed Central

    Wise, Lauren A.; Laughlin-Tommaso, Shannon K.

    2015-01-01

    Uterine leiomyomata (UL) have a substantial impact on women's health, but relatively few studies have identified opportunities for primary prevention of these neoplasms. Most established risk factors are not modifiable, including premenopausal age, African ancestry, age at menarche, and childbearing history. The main challenge in studying UL is that a large proportion of tumors are asymptomatic. Herein, we review the epidemiology of UL from published studies to date. We highlight the advantages of ultrasound screening studies and the ways in which their innovative methods have helped clarify the etiology of disease. We conclude with a discussion of promising new hypotheses. PMID:26744813

  1. Metabolomics in epidemiology: from metabolite concentrations to integrative reaction networks

    PubMed Central

    Fearnley, Liam G; Inouye, Michael

    2016-01-01

    Metabolomics is becoming feasible for population-scale studies of human disease. In this review, we survey epidemiological studies that leverage metabolomics and multi-omics to gain insight into disease mechanisms. We outline key practical, technological and analytical limitations while also highlighting recent successes in integrating these data. The use of multi-omics to infer reaction rates is discussed as a potential future direction for metabolomics research, as a means of identifying biomarkers as well as inferring causality. Furthermore, we highlight established analysis approaches as well as simulation-based methods currently used in single- and multi-cell levels in systems biology. PMID:27118561

  2. Epidemiology of Uterine Fibroids: From Menarche to Menopause.

    PubMed

    Wise, Lauren A; Laughlin-Tommaso, Shannon K

    2016-03-01

    Uterine leiomyomata (UL) have a substantial impact on women's health, but relatively few studies have identified opportunities for primary prevention of these neoplasms. Most established risk factors are not modifiable, including premenopausal age, African ancestry, age at menarche, and childbearing history. The main challenge in studying UL is that a large proportion of tumors are asymptomatic. Herein, we review the epidemiology of UL from published studies to date. We highlight the advantages of ultrasound screening studies and the ways in which their innovative methods have helped clarify the etiology of disease. We conclude with a discussion of promising new hypotheses.

  3. [Epidemiological imaginary in Campania Region].

    PubMed

    Greco, Pietro

    2012-01-01

    The interviews on the epidemiological imaginary, collected within the framework of the project Sebiorec,(1) clearly demonstrate that also in Campania, on the border between the provinces of Naples and Caserta - where the issue of waste and land devastation take forms that are unprecedented compared to any other part of Europe - there is a widespread, strong, sacrosanct demand of participation in environment and health management. The request of deliberative ecological democracy is pressing.(2) There is an urgent need to meet that plethora of rights emerging in the "knowledge society" and in the "risk society" that someone has called "rights for scientific citizenship."(3) This request of the population of Campania, net of local cultural specificity, it is quite similar to that of the people of any other region of Europe. The context in which this request of participation is expressed, however, is quite different. Not only and not just for that real or perceived social pre-modern and familist web that would replace a modern civil society in Campania and all across the Southern Italian regions, but also and especially for some structural causes that we here try to list. Campania is a unique region in Europe - in many ways different even from other regions of southern Italy - due to the conjunction of at least five factors, not independent from each other. 1) The presence of a widespread organized crime which, in many areas, metropolitan and non-metropolitan alike, and especially in the provinces of Naples and Caserta, is a sort of state against the State and has one of its main levers of power and a major source of its wealth in the illegal control of the territory, in its different dimensions (military, but also economic, social and even cultural). 2) A huge social and economic disintegration, exacerbated in the last twenty years by a process of deindustrialization (until the early nineties Naples was the fifth industrial city of Italy, today it is a desert where

  4. Forecasting Epidemiological Consequences of Maternal Immunization

    PubMed Central

    Bento, Ana I.; Rohani, Pejman

    2016-01-01

    Background. The increase in the incidence of whooping cough (pertussis) in many countries with high vaccination coverage is alarming. Maternal pertussis immunization has been proposed as an effective means of protecting newborns during the interval between birth and the first routine dose. However, there are concerns regarding potential interference between maternal antibodies and the immune response elicited by the routine schedule, with possible long-term population-level effects. Methods. We formulated a transmission model comprising both primary routine and maternal immunization. This model was examined to evaluate the long-term epidemiological effects of routine and maternal immunization, together with consequences of potential immune interference scenarios. Results. Overall, our model demonstrates that maternal immunization is an effective strategy in reducing the incidence of pertussis in neonates prior to the onset of the primary schedule. However, if maternal antibodies lead to blunting, incidence increases among older age groups. For instance, our model predicts that with 60% routine and maternal immunization coverage and 30% blunting, the incidence among neonates (0–2 months) is reduced by 43%. Under the same scenario, we observe a 20% increase in incidence among children aged 5–10 years. However, the downstream increase in the older age groups occurs with a delay of approximately a decade or more. Conclusions. Maternal immunization has clear positive effects on infant burden of disease, lowering mean infant incidence. However, if maternally derived antibodies adversely affect the immunogenicity of the routine schedule, we predict eventual population-level repercussions that may lead to an overall increase in incidence in older age groups. PMID:27838674

  5. Synthetic Cannabinoids: Epidemiology, Pharmacodynamics, and Clinical Implications*

    PubMed Central

    Castaneto, Marisol S.; Gorelick, David A.; Desrosiers, Nathalie A.; Hartman, Rebecca L.; Pirard, Sandrine; Huestis, Marilyn A.

    2014-01-01

    Background Synthetic cannabinoids (SC) are a heterogeneous group of compounds developed to probe the endogenous cannabinoid system or as potential therapeutics. Clandestine laboratories subsequently utilized published data to develop SC variations marketed as abuseable “designer drugs.” In the early 2000’s, SC became popular as “legal highs” under brand names such as “Spice” and “K2,” in part due to their ability to escape detection by standard cannabinoid screening tests. The majority of SC detected in herbal products have greater binding affinity to the cannabinoid CB1 receptor than does Δ9-tetrahydrocannabinol (THC), the primary psychoactive compound in the cannabis plant, and greater affinity at the CB1 than the CB2 receptor. In-vitro and animal in-vivo studies show SC pharmacological effects 2-100 times more potent than THC, including analgesic, anti-seizure, weight-loss, anti-inflammatory, and anti-cancer growth effects. SC produce physiological and psychoactive effects similar to THC, but with greater intensity, resulting in medical and psychiatric emergencies. Human adverse effects include nausea and vomiting, shortness of breath or depressed breathing, hypertension, tachycardia, chest pain, muscle twitches, acute renal failure, anxiety, agitation, psychosis, suicidal ideation, and cognitive impairment. Long-term or residual effects are unknown. Due to these public health consequences, many SC are classified as controlled substances. However, frequent structural modification by clandestine laboratories results in a stream of novel SC that may not be legally controlled or detectable by routine laboratory tests. Methods We present here a comprehensive review, based on a systematic electronic literature search, of SC epidemiology and pharmacology and their clinical implications. PMID:25220897

  6. Extrahuman Epidemiology of Acinetobacter baumannii in Lebanon

    PubMed Central

    Rafei, Rayane; Hamze, Monzer; Pailhoriès, Hélène; Eveillard, Matthieu; Marsollier, Laurent; Joly-Guillou, Marie-Laure; Dabboussi, Fouad

    2015-01-01

    The presence of Acinetobacter baumannii outside hospitals is still a controversial issue. The objective of our study was to explore the extrahospital epidemiology of A. baumannii in Lebanon. From February 2012 to October 2013, a total of 73 water samples, 51 soil samples, 37 raw cow milk samples, 50 cow meat samples, 7 raw cheese samples, and 379 animal samples were analyzed by cultural methods for the presence of A. baumannii. Species identification was performed by rpoB gene sequencing. Antibiotic susceptibility was investigated, and the A. baumannii population was studied by two genotyping approaches: multilocus sequence typing (MLST) and blaOXA-51 sequence-based typing (SBT). A. baumannii was detected in 6.9% of water samples, 2.7% of milk samples, 8.0% of meat samples, 14.3% of cheese samples, and 7.7% of animal samples. All isolates showed a susceptible phenotype against most of the antibiotics tested and lacked carbapenemase-encoding genes, except one that harbored a blaOXA-143 gene. MLST analysis revealed the presence of 36 sequence types (STs), among which 24 were novel STs reported for the first time in this study. blaOXA-51 SBT showed the presence of 34 variants, among which 21 were novel and all were isolated from animal origins. Finally, 30 isolates had new partial rpoB sequences and were considered putative new Acinetobacter species. In conclusion, animals can be a potential reservoir for A. baumannii and the dissemination of new emerging carbapenemases. The roles of the novel animal clones identified in community-acquired infections should be investigated. PMID:25616788

  7. Epidemiology of fatty liver: An update

    PubMed Central

    Bedogni, Giorgio; Nobili, Valerio; Tiribelli, Claudio

    2014-01-01

    We provide a concise review of the main epidemiological literature on fatty liver (FL) published between January 2011 and October 2013. The findings from the literature will be considered in light of the already available knowledge. We discuss the limitations inherent in the categorization of FL into non-alcoholic and alcoholic FL, the potential relevance of FL as an independent predictor of cardiometabolic disease, and recent research addressing the role of FL as an independent predictor of mortality. This review is organized as a series of answers to relevant questions about the epidemiology of FL. PMID:25083078

  8. Applications of fractional calculus to epidemiological models

    NASA Astrophysics Data System (ADS)

    Skwara, Urszula; Martins, José; Ghaffari, Peyman; Aguiar, Maíra; Boto, João; Stollenwerk, Nico

    2012-09-01

    Epidemiological spreading does not only happen from person to neighbouring person but often over wide distances, when infected but asymptomatic persons travel and carry infection to others over wide distances. Superdiffusion has been suggested to model such spreading in spatially restriced contact networks, i.e. there is still a notion of geographical distance, but spreading happens with high probability proportional to large distances. From fractional calculus several ways of describing superdiffusion are know. Here we investigate the representation in Fourier space and which is easily generalizable to higher dimensional space in order to compare with stochastic models of epidemiological spreading.

  9. [Tuberculosis epidemiology in Catalonia: 1982-1989].

    PubMed

    Alcaide Megías, J; Altet Gómez, M N; Taberner Zaragoza, J L; Garrido Morales, P; Salleras Sanmartí, L

    1990-10-27

    The epidemiological indicators of tuberculosis in Catalonia and their trends since 1982 were evaluated. It was shown that the reported morbidity rate has increased because of an increased number of reports, but it probably is still lower than the real one. The epidemiological value of the parameters of tuberculous infection was also shown, particularly the yearly infection rate (YIR), or probability of an individual to be infected. In spite of the multiple interferences that these indexes may have undergone during the past BCG vaccination campaign, their reduction is very important, the yearly reduction of YIR being estimated in 11%.

  10. Epidemiology of asbestos-related diseases.

    PubMed Central

    Lemen, R A; Dement, J M; Wagoner, J K

    1980-01-01

    This paper is intended to give the reader an overview of the epidemiology of asbestos-related diseases and is restricted to primarily occupational exposure studies. However, some mention of nonoccupational exposures are made because of their direct relationship to a worker or to a secondary occupational source. Over 100 epidemiological studies are reviewed, dating back to the first case of asbestos-associated disease reported by Montague Murray in 1906. The studies are divided by specific fiber type and by specific disease outcomes and the interaction of asbestos and cigarette smoking is discussed in great detail. PMID:6993197

  11. Candida and candidaemia. Susceptibility and epidemiology.

    PubMed

    Arendrup, Maiken Cavling

    2013-11-01

    In our part of the world invasive fungal infections include invasive yeast infections with Candida as the absolutely dominating pathogen and invasive mould infections with Aspergillus as the main organism. Yeasts are part of our normal micro-flora and invasive infections arise only when barrier leakage or impaired immune function occurs. On the contrary, moulds are ubiquitous in the nature and environment and their conidia inhaled at a daily basis. Hence invasive mould infections typically arise from the airways whereas invasive yeast infections typically enter the bloodstream causing fungaemia. Candida is by far the most common fungal blood stream pathogen; hence this genus has been the main focus of this thesis. As neither the Danish epidemiology nor the susceptibility of fungal pathogens was well described when we initiated our studies we initially wanted to be able to include animal models in our work. Therefore, a comprehensive animal study was undertaken comparing the virulence in a haematogenous mouse model of eight different Candida species including the five most common ones in human infections (C. albicans, C. glabrata, C. krusei, C. parapsilosis and C. tropicalis and in addition three rarer species C. guilliermondii, C. lusitaniae and C. kefyr). We found remarkable differences in the virulence among these species and were able to group the species according to decreasing virulence in three groups I: C. albicans and C. tropicalis, II: C. glabrata, C. lusitaniae and C. kefyr, and III: C. krusei, C. parapsilosis and C. guilliermondii. Apart from being necessary for our subsequent animal experiments exploring in vivo antifungal susceptibility, these findings also helped us understand at least part of the reason for the differences in the epidemiology and the pitfalls associated with the establishment of genus rather than species specific breakpoints. In example, it was less surprising that C. albicans has been the dominant pathogen and associated with a

  12. Impact of environmental inequity on health outcome: where is the epidemiological evidence?

    PubMed Central

    René, A. A.; Daniels, D. E.; Martin, S. A.

    2000-01-01

    A significant amount of evidence reveals a presence of environmental inequity. Although there is a disproportionate distribution of waste treatment, storage and disposal facilities, and chemical and manufacturing plants in minority and low-income communities in the United States, little research has been devoted to show any associations based on analytic epidemiological methods. To date, attempts to quantify health disparities have included demographic data, race, sex, income, other socioeconomic factors, and broad symptomatic survey instruments. To study this, we examined the latest epidemiological evidence documenting the existence of adverse health impacts resulting from environmental inequity. We observed that the overwhelming majority of studies were descriptive in nature and lacked comparison populations. As a result, we believe that further research based on analytic epidemiological methods would further contribute to the determination of the cause-effect relationship between environmental exposure and health outcome. PMID:10918762

  13. [The impact of the contingents of penal system onto the tuberculosis epidemiological situation on the regional level].

    PubMed

    Sazykina, I G

    2008-01-01

    The effect of the special contingents of penal system on the tuberculosis epidemiological indicators in a particular region. The findings testify that under the conditions existed in the Orenburgskaya oblast the negative effect of the contingents of the sentence execution service of the Russian Federation on the tuberculosis epidemiological indicators is rather strong and besides is significantly higher in comparison with the average values typical for the Russian Federation. This kind of epidemiological analysis would be useful for functioning of the organizational and methodical services of other regional tuberculosis dispensers for the purpose of developing well-grounded additional managerial decisions.

  14. Epidemiological and control aspects of schistosomiasis in Brazilian endemic areas.

    PubMed

    Coura, J R; Amaral, R S

    2004-01-01

    The present work analyzes the epidemiology of schistosomiasis in Brazil, its expansion, the attempts to control the disease, and the overall difficulties. The authors present the distribution of schistosomiasis intermediary hosts in Brazil, the migration routes of the human population, and disease distribution in highly and lowly endemic areas and isolated foci. They also analyze the controlling programs developed from 1977 to 2002, indicating the prevalence evolution and the reduction of disease morbi-mortality. In addition, the authors also evaluate controlling methods and conclude that: (a) no isolated method is able to control schistosomiasis, and every controlling program should consider the need of a multidisciplinary application of existing methods; (b) in long term, basic sanitation, potable water supply, as well as sanitary education, and community effective participation are important for infection control; (c) in short term, specific treatment at endemic areas, associated with control of intermediary hosts at epidemiologically important foci, are extremely relevant for controlling disease morbidity, although not enough for interrupting infection transmission.

  15. Discovering environmental cancer: Wilhelm Hueper, post-World War II epidemiology, and the vanishing clinician's eye.

    PubMed Central

    Sellers, C

    1997-01-01

    Today, our understanding of and approach to the exogenous causes of cancer are dominated by epidemiological practices that came into widespread use after World War II. This paper examines the forces, considerations, and controversies that shaped postwar risk factor epidemiology in the United States. It is argued that, for all of the new capabilities it brought, this risk factor epidemiology has left us with less of a clinical eye for unrecognized cancer hazards, especially from limited and localized exposures in the work-place. The focus here is on Wilhelm Hueper, author of the first textbook on occupational cancer (1942). Hueper became the foremost spokesman for earlier identification practices centering on occupational exposures. The new epidemiological methods and associated institutions that arose in the 1940s and 1950s bore an unsettled relation to earlier claims and methods that some, Hueper among them, interpreted as a challenge. Hueper's critique of the new epidemiology identified some of its limitations and potentially debilitating consequences that remain with us today. Images p1825-a p1827-a p1829-a PMID:9366640

  16. Parameter and uncertainty estimation for mechanistic, spatially explicit epidemiological models

    NASA Astrophysics Data System (ADS)

    Finger, Flavio; Schaefli, Bettina; Bertuzzo, Enrico; Mari, Lorenzo; Rinaldo, Andrea

    2014-05-01

    Epidemiological models can be a crucially important tool for decision-making during disease outbreaks. The range of possible applications spans from real-time forecasting and allocation of health-care resources to testing alternative intervention mechanisms such as vaccines, antibiotics or the improvement of sanitary conditions. Our spatially explicit, mechanistic models for cholera epidemics have been successfully applied to several epidemics including, the one that struck Haiti in late 2010 and is still ongoing. Calibration and parameter estimation of such models represents a major challenge because of properties unusual in traditional geoscientific domains such as hydrology. Firstly, the epidemiological data available might be subject to high uncertainties due to error-prone diagnosis as well as manual (and possibly incomplete) data collection. Secondly, long-term time-series of epidemiological data are often unavailable. Finally, the spatially explicit character of the models requires the comparison of several time-series of model outputs with their real-world counterparts, which calls for an appropriate weighting scheme. It follows that the usual assumption of a homoscedastic Gaussian error distribution, used in combination with classical calibration techniques based on Markov chain Monte Carlo algorithms, is likely to be violated, whereas the construction of an appropriate formal likelihood function seems close to impossible. Alternative calibration methods, which allow for accurate estimation of total model uncertainty, particularly regarding the envisaged use of the models for decision-making, are thus needed. Here we present the most recent developments regarding methods for parameter and uncertainty estimation to be used with our mechanistic, spatially explicit models for cholera epidemics, based on informal measures of goodness of fit.

  17. Examination of Different Exposure Metrics in an Epidemiological Study

    EPA Science Inventory

    Epidemiological studies of air pollution have traditionally relied upon measurements of ambient concentration from central-site monitoring stations as surrogates of population exposures. However, depending on the epidemiological study design, this approach may introduce exposure...

  18. An Epidemiologic Perspective. Does Running Cause Osteoarthritis?

    ERIC Educational Resources Information Center

    Eichner, Edward R.

    1989-01-01

    A review of literature on exercise and arthritis considers relevant epidemiologic and experimental studies of animals and humans, focusing on the relationship between running and osteoarthritis. No conclusive evidence exists that running causes osteoarthritis; research trends suggest that running may slow the functional aspects of musculoskeletal…

  19. Epidemiology of hepatitis C virus in Iran

    PubMed Central

    Taherkhani, Reza; Farshadpour, Fatemeh

    2015-01-01

    In Iran, the prevalence of hepatitis C virus (HCV) infection is relatively low according to the population-based epidemiological studies. However, the epidemiology of HCV is changing and the rate of HCV infection is increasing due to the growth in the number of injecting drug users in the society. In addition, a shift has occurred in the distribution pattern of HCV genotypes among HCV-infected patients in Iran. Genotype 1a is the most prevalent genotype in Iran, but in recent years, an increase in the frequency of 3a and a decrease in 1a and 1b have been reported. These variations in the epidemiology of HCV reflect differences in the routes of transmission, status of public health, lifestyles, and risk factors in different groups and geographic regions of Iran. Health policy makers should consider these differences to establish better strategies for control and prevention of HCV infection. Therefore, this review was conducted to present a clear view regarding the current epidemiology of HCV infection in Iran. PMID:26478671

  20. Epidemiology of hepatitis C virus in Iran.

    PubMed

    Taherkhani, Reza; Farshadpour, Fatemeh

    2015-10-14

    In Iran, the prevalence of hepatitis C virus (HCV) infection is relatively low according to the population-based epidemiological studies. However, the epidemiology of HCV is changing and the rate of HCV infection is increasing due to the growth in the number of injecting drug users in the society. In addition, a shift has occurred in the distribution pattern of HCV genotypes among HCV-infected patients in Iran. Genotype 1a is the most prevalent genotype in Iran, but in recent years, an increase in the frequency of 3a and a decrease in 1a and 1b have been reported. These variations in the epidemiology of HCV reflect differences in the routes of transmission, status of public health, lifestyles, and risk factors in different groups and geographic regions of Iran. Health policy makers should consider these differences to establish better strategies for control and prevention of HCV infection. Therefore, this review was conducted to present a clear view regarding the current epidemiology of HCV infection in Iran.

  1. Breast Cancer Epidemiology in Puerto Rico

    DTIC Science & Technology

    2009-06-01

    been develop successfully. The infrastructure for developing the pilot case-control study has been established. The work, communication and...the study has been completed successfully (initial training in the study protocol, obtaining all institution and DOD IRBs and HIPAA approvals...designing the questionnaire, etc.) 15. SUBJECT TERMS Breast cancer; population-based study , epidemiology 16. SECURITY CLASSIFICATION OF: 17

  2. Impulsive Vaccination for an Epidemiology Model

    NASA Astrophysics Data System (ADS)

    De la Sen, M.; Garrido, A. J.

    2017-03-01

    This paper investigates sufficient conditions of almost periodic sand periodic solutions of an integral model under impulsive controls. Since the model is of generic epidemiological interest, such impulsive controls are either vaccination actions or abrupt variations of the infected population due to infected immigration or lost of infective numbers due to either vaccination or lost of infected population by out-migration.

  3. Rocky Mountain Spotted Fever: Statistics and Epidemiology

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Symptoms, Diagnosis, and Treatment Statistics and Epidemiology ...

  4. Cancer and Aging: Epidemiology and Methodological Challenges

    PubMed Central

    Pedersen, Jacob K; Engholm, Gerda; Skytthe, Axel; Christensen, Kaare

    2016-01-01

    Epidemiological cancer data shed light on key questions within basic science, clinical medicine and public health. For decades, Denmark has had linkable health registers that contain individual level data on the entire population with virtually complete follow-up. This has enabled high quality studies of cancer epidemiology and minimized the challenges often faced in many countries, such as uncertain identification of the study base, age misreporting, and low validity of the cancer diagnoses. However, methodological challenges still remain to be addressed, especially in cancer epidemiology studies among the elderly and the oldest-old. E.g., a characteristic pattern for many cancer types is that the incidence increases up to a maximum at about ages 75 to 90 years and is then followed by a decline or a leveling off at the oldest ages. It has been suggested that the oldest individuals may be asymptomatic, or even insusceptible to cancer. An alternative interpretation is that this pattern is an artifact due to lower diagnostic intensity among the elderly and oldest-old caused by higher levels of co-morbidities in this age group. Currently, the available cancer epidemiology data are not able to provide clear evidence for any of these hypotheses. PMID:26825001

  5. Epidemiology of Falls in Older Age

    ERIC Educational Resources Information Center

    Peel, Nancye May

    2011-01-01

    Worldwide, falls among older people are a public health concern because of their frequency and adverse consequences in terms of morbidity, mortality, and quality of life, as well as their impact on health system services and costs. This epidemiological review outlines the public health burden of falls and fall-related injuries and the impact of…

  6. Ethnicity/race, ethics, and epidemiology.

    PubMed Central

    Whaley, Arthur L.

    2003-01-01

    Ethnicity/race is a much-studied variable in epidemiology. There has been little consensus about what self-reported ethnicity/race represents, but it is a measure of some combination of genetic, socioeconomic, and cultural factors. The present article will attempt to: 1.) Elucidate the limitations of contemporary discourse on ethnicity/race that emphasizes the genetic and socioeconomic dimensions as competing explanatory frameworks; 2.) Demonstrate how considerable attention to the cultural dimension facilitates understanding of race differences in health-related outcomes; and 3.) Discuss interpretations of disparities in health status of African Americans versus European Americans from an ethical perspective. A major challenge to the discourse on ethnicity/race and health being limited to socioeconomic and genetic considerations is the lack of attention to the third alternative of a cultural perspective. The combined cultural ideologies of individualism and racism undermine the utility of epidemiologic research in health promotion and disease prevention campaigns aimed at reducing the racial gaps in health status. An ethical analysis supplements the cultural perspective. Ethics converge with culture on the notion of values influencing the study of ethnicity/race in epidemiology. A cultural approach to the use of ethnicity/race in epidemiologic research addresses methodological limitations, public health traditions, and ethical imperatives. PMID:12934873

  7. The Epidemiology of Human Immunodeficiency Virus Infection.

    ERIC Educational Resources Information Center

    Glasner, Peter D.; Kaslow, Richard A.

    1990-01-01

    Reviews epidemiology and natural history of human immunodeficiency virus-Type 1 (HIV-1) infection. Discusses early and late clinical manifestations, diagnosis of infection, incubation and latency periods, and survival time. Reviews data from published literature on distribution of HIV infection in adult United States population and factors that…

  8. Conceptual and methodological issues in epidemiology: An overview.

    PubMed

    Broadbent, Alex

    2011-10-01

    In 2010 a series of workshops on philosophical and methodological issues in epidemiology was held at the University of Cambridge. The papers in this volume arise from those workshops. This paper represents an effort to identify, in broad brush, some of the major conceptual and methodological issues in epidemiology, which form the basis of an emerging focus on the philosophy of epidemiology.

  9. MOLECULAR EPIDEMIOLOGY: POTENTIAL IMPACTS ON THE ASSESSMENT OF PUBLIC HEALTH

    EPA Science Inventory

    Introduction

    The term "molecular epidemiology" has been used to cover a broad range of scientific activities, often without specific reference to epidemiology. In fact, as noted by Foxman and Riley [1],molecular epidemiology has often been described almost exclusively in...

  10. The World Health Organization and the contested beginnings of psychiatric epidemiology as an international discipline: one rope, many strands.

    PubMed

    Lovell, Anne M

    2014-08-01

    This paper focuses on the relatively late emergence of psychiatric epidemiology as an international discipline, through local-global exchanges during the first 15 years of the World Health Organization (WHO). Building an epidemiological canon within WHO's Mental Health Programme faced numerous obstacles. First, an idealist notion of mental health inherent in WHO's own definition of health contributed to tensions around the object of psychiatric epidemiology. Second, the transfer of methods from medical epidemiology to research on mental disorders required mobilizing conceptual justifications, including a 'contagion argument'. Third, epidemiological research at WHO was stymied by other public health needs, resource scarcity and cultural barriers. This history partly recapitulates the development of psychiatric epidemiology in North America and Europe, but is also shaped by concerns in the developing world, translated through first-world 'experts'. Resolving the tensions arising from these obstacles allowed WHO to establish its international schizophrenia research, which in turn provided proof of concept for psychiatric epidemiology in the place of scepticism within and without psychiatry.

  11. Lessons Learned From Methodological Validation Research in E-Epidemiology

    PubMed Central

    Assmann, Karen; Andreeva, Valentina; Castetbon, Katia; Méjean, Caroline; Touvier, Mathilde; Salanave, Benoît; Deschamps, Valérie; Péneau, Sandrine; Fezeu, Léopold; Julia, Chantal; Allès, Benjamin; Galan, Pilar; Hercberg, Serge

    2016-01-01

    Background Traditional epidemiological research methods exhibit limitations leading to high logistics, human, and financial burden. The continued development of innovative digital tools has the potential to overcome many of the existing methodological issues. Nonetheless, Web-based studies remain relatively uncommon, partly due to persistent concerns about validity and generalizability. Objective The objective of this viewpoint is to summarize findings from methodological studies carried out in the NutriNet-Santé study, a French Web-based cohort study. Methods On the basis of the previous findings from the NutriNet-Santé e-cohort (>150,000 participants are currently included), we synthesized e-epidemiological knowledge on sample representativeness, advantageous recruitment strategies, and data quality. Results Overall, the reported findings support the usefulness of Web-based studies in overcoming common methodological deficiencies in epidemiological research, in particular with regard to data quality (eg, the concordance for body mass index [BMI] classification was 93%), reduced social desirability bias, and access to a wide range of participant profiles, including the hard-to-reach subgroups such as young (12.30% [15,118/122,912], <25 years) and old people (6.60% [8112/122,912], ≥65 years), unemployed or homemaker (12.60% [15,487/122,912]), and low educated (38.50% [47,312/122,912]) people. However, some selection bias remained (78.00% (95,871/122,912) of the participants were women, and 61.50% (75,590/122,912) had postsecondary education), which is an inherent aspect of cohort study inclusion; other specific types of bias may also have occurred. Conclusions Given the rapidly growing access to the Internet across social strata, the recruitment of participants with diverse socioeconomic profiles and health risk exposures was highly feasible. Continued efforts concerning the identification of specific biases in e-cohorts and the collection of comprehensive and

  12. [The 90th anniversary of the Center of State Sanitation-and-Epidemiological Control of Privolzhsky-Ural military region].

    PubMed

    Krylov, I K; Tomberg, A L

    2009-10-01

    There was exposed in brief the history of "The 1321" Center of state sanitation-and-epidemiological control of Privolzhsky-Ural military region". Nowadays it's a profile institute, where high-qualified and low-grade physicians are working. The Center successfully solves the tasks of securing of sanitarium-epidemiological well-being of regional troops, realizes a grand volume of education-methodical, science-practical and info-analyzing work.

  13. Epidemiology and the Tobacco Epidemic: How Research on Tobacco and Health Shaped Epidemiology.

    PubMed

    Samet, Jonathan M

    2016-03-01

    In this article, I provide a perspective on the tobacco epidemic and epidemiology, describing the impact of the tobacco-caused disease epidemic on the field of epidemiology. Although there is an enormous body of epidemiologic evidence on the associations of smoking with health, little systematic attention has been given to how decades of research have affected epidemiology and its practice. I address the many advances that resulted from epidemiologic research on smoking and health, such as demonstration of the utility of observational designs and important parameters (the odds ratio and the population attributable risk), guidelines for causal inference, and systematic review approaches. I also cover unintended and adverse consequences for the field, including the strategy of doubt creation and the recruitment of epidemiologists by the tobacco industry to serve its mission. The paradigm of evidence-based action for addressing noncommunicable diseases began with the need to address the epidemic of tobacco-caused disease, an imperative for action documented by epidemiologic research.

  14. Cultural psychiatry and epidemiology: researching the means, methods and meanings.

    PubMed

    Bhui, Kamaldeep

    2011-04-01

    This article describes my developing interest in cultural psychiatry. This is both a challenging and yet a privileged opportunity to reflect on my research and clinical work over the last 25 years. I describe cultural and interpersonal influences on my thinking and interests, and the development of my research career moving from health services research of specialist services, to primary care research to public mental health research. Specifically, social and cultural influences on risks and responses to mental illness are discussed, as are pathways to care, the recognition of mental illness, and public health and cultural psychiatry research.

  15. Proceedings of the third international molecular pathological epidemiology (MPE) meeting.

    PubMed

    Campbell, Peter T; Rebbeck, Timothy R; Nishihara, Reiko; Beck, Andrew H; Begg, Colin B; Bogdanov, Alexei A; Cao, Yin; Coleman, Helen G; Freeman, Gordon J; Heng, Yujing J; Huttenhower, Curtis; Irizarry, Rafael A; Kip, N Sertac; Michor, Franziska; Nevo, Daniel; Peters, Ulrike; Phipps, Amanda I; Poole, Elizabeth M; Qian, Zhi Rong; Quackenbush, John; Robins, Harlan; Rogan, Peter K; Slattery, Martha L; Smith-Warner, Stephanie A; Song, Mingyang; VanderWeele, Tyler J; Xia, Daniel; Zabor, Emily C; Zhang, Xuehong; Wang, Molin; Ogino, Shuji

    2017-02-01

    Molecular pathological epidemiology (MPE) is a transdisciplinary and relatively new scientific discipline that integrates theory, methods, and resources from epidemiology, pathology, biostatistics, bioinformatics, and computational biology. The underlying objective of MPE research is to better understand the etiology and progression of complex and heterogeneous human diseases with the goal of informing prevention and treatment efforts in population health and clinical medicine. Although MPE research has been commonly applied to investigating breast, lung, and colorectal cancers, its methodology can be used to study most diseases. Recent successes in MPE studies include: (1) the development of new statistical methods to address etiologic heterogeneity; (2) the enhancement of causal inference; (3) the identification of previously unknown exposure-subtype disease associations; and (4) better understanding of the role of lifestyle/behavioral factors on modifying prognosis according to disease subtype. Central challenges to MPE include the relative lack of transdisciplinary experts, educational programs, and forums to discuss issues related to the advancement of the field. To address these challenges, highlight recent successes in the field, and identify new opportunities, a series of MPE meetings have been held at the Dana-Farber Cancer Institute in Boston, MA. Herein, we share the proceedings of the Third International MPE Meeting, held in May 2016 and attended by 150 scientists from 17 countries. Special topics included integration of MPE with immunology and health disparity research. This meeting series will continue to provide an impetus to foster further transdisciplinary integration of divergent scientific fields.

  16. Using Epidemiology and Neurotoxicology to Reduce Risks to Young Workers

    PubMed Central

    Rohlman, Diane S.; Nuwayhid, Iman; Ismail, Ahmed; Saddik, Basema

    2012-01-01

    Children around the world are working in hazardous or unsafe conditions and they are at risk to injury through manual labor and susceptible to poisoning due to chemical exposures in the work place. Because of their behavior and the developmental changes occurring throughout childhood and adolescence children are more vulnerable to injury. Often children work because of economic necessity, coming from families living in extreme poverty, with poor housing conditions, unsafe water supplies, poor sanitation, and inadequate food supplies making them even more vulnerable to poor developmental outcomes. This presents a multifaceted problem that can be challenging to address. Although many studies have examined occupational risks among adults very few studies have examined the impact of these risks on children. This paper reflects a summary of the talks from the symposium “Using Epidemiology and Neurotoxicology to Reduce Risks to Young Workers” presented at the 13th International Neurotoxicology Association Meeting and the 11th International Symposium on Neurobehavioral Methods and Effects in Occupational and Environmental Health in Xi’an China in June 2011. Epidemiological studies have demonstrated that children are exposed to various neurotoxicants, show increased symptoms and health problems and are working in hazardous conditions with minimal safety restrictions. Other studies have identified neurotoxicology effects in children from occupational exposures. Prevention methods have potential for reducing risks to young workers short of eliminating child labor and should be addressed to multiple stakeholders, parents, employers and children. PMID:22394482

  17. The Brazilian Football Association (CBF) model for epidemiological studies on professional soccer player injuries

    PubMed Central

    Arliani, Gustavo Gonçalves; Belangero, Paulo Santoro; Runco, Jose Luiz; Cohen, Moisés

    2011-01-01

    OBJECTIVE: This study aims to establish a national methodological model for epidemiological studies on professional soccer player injuries and to describe the numerous relevant studies previously published on this topic. INTRODUCTION: The risk of injury in professional soccer is high. However, previous studies of injury risk in Brazil and other countries have been characterized by large variations in study design and data collection methods as well as definitions of injury, standardized diagnostic criteria, and recovery times. METHODS: A system developed by the Union of European Football for epidemiological studies on professional soccer players is being used as a starting point to create a methodological model for the Brazilian Football Association. To describe the existing studies on professional soccer player injuries, we developed a search strategy to identify relevant epidemiological studies. We included the Latin American and Caribbean Center on Health Sciences and Medline databases in our study. RESULTS: We considered 60 studies from Medline and 16 studies from the Latin American and Caribbean Center on Health Sciences in the final analysis. Twelve studies were selected for final inclusion in this review: seven from the Latin American and Caribbean Center on Health Sciences and five from Medline. We identified a lack of uniformity in the study design, data collection methods, injury definitions, standardized diagnostic criteria, and the definition of recovery time. Based on the information contained within these articles, we developed a model for epidemiological studies for the Brazilian Football Association. CONCLUSIONS: There is no uniform model for epidemiological studies of professional soccer injuries. Here, we propose a novel model to be applied for epidemiological studies of professional soccer player injuries in Brazil and throughout the world. PMID:22012041

  18. Shared Dosimetry Error in Epidemiological Dose-Response Analyses

    PubMed Central

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre

    2015-01-01

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takes up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed. PMID:25799311

  19. Epidemiological Surveillance of Lymphocryptovirus Infection in Wild Bonobos

    PubMed Central

    Yoshida, Tomoyuki; Takemoto, Hiroyuki; Sakamaki, Tetsuya; Tokuyama, Nahoko; Hart, John; Hart, Terese; Dupain, Jef; Cobden, Amy; Mulavwa, Mbangi; Kawamoto, Yoshi; Kaneko, Akihisa; Enomoto, Yuki; Sato, Eiji; Kooriyama, Takanori; Miyabe-Nishiwaki, Takako; Suzuki, Juri; Saito, Akatsuki; Okamoto, Munehiro; Tomonaga, Masaki; Matsuzawa, Tetsuro; Furuichi, Takeshi; Akari, Hirofumi

    2016-01-01

    Lymphocryptovirus (LCV) is one of the major gena in the herpesvirus family and is widely disseminated among primates. LCVs of human and rhesus macaques are shown to be causative agents of a number of malignant diseases including lymphoma and carcinoma. Bonobos (Pan paniscus) are highly endangered and the least studied species of the great apes. Considering the potential pathogenicity of the LCV that might threaten the fate of wild bonobos, population-based epidemiological information in terms of LCV prevalence in different location of Bonobo’s habitats will help propose improved conservation strategies for the bonobos. However, such data are not available yet because it is very difficult to collect blood samples in the wild and thus virtually impossible to conduct sero-epidemiological study on the wild ape. In order to overcome this issue, we focused on evaluating anti-LCV IgA in the feces of bonobos, which are available in a non-invasive manner. Preliminary study showed that anti-LCV IgA but not IgG was efficiently and reproducibly detected in the feces of captive chimpanzees. It is noteworthy that the fecal IgA-positive individuals were seropositive for both anti-LCV IgG and IgA and that the IgA antibodies in both sera and feces were also detectable by Western blotting assay. These results indicate that the detection of fecal anti-LCV IgA is likely a reliable and feasible for epidemiological surveillance of LCV prevalence in the great apes. We then applied this method and found that 31% of wild bonobos tested were positive for anti-LCV IgA antibody in the feces. Notably, the positivity rates varied extensively among their sampled populations. In conclusion, our results in this study demonstrate that LCV is highly disseminated among wild bonobos while the prevalence is remarkably diverse in their population-dependent manner. PMID:27570523

  20. Regression Discontinuity for Causal Effect Estimation in Epidemiology.

    PubMed

    Oldenburg, Catherine E; Moscoe, Ellen; Bärnighausen, Till

    Regression discontinuity analyses can generate estimates of the causal effects of an exposure when a continuously measured variable is used to assign the exposure to individuals based on a threshold rule. Individuals just above the threshold are expected to be similar in their distribution of measured and unmeasured baseline covariates to individuals just below the threshold, resulting in exchangeability. At the threshold exchangeability is guaranteed if there is random variation in the continuous assignment variable, e.g., due to random measurement error. Under exchangeability, causal effects can be identified at the threshold. The regression discontinuity intention-to-treat (RD-ITT) effect on an outcome can be estimated as the difference in the outcome between individuals just above (or below) versus just below (or above) the threshold. This effect is analogous to the ITT effect in a randomized controlled trial. Instrumental variable methods can be used to estimate the effect of exposure itself utilizing the threshold as the instrument. We review the recent epidemiologic literature reporting regression discontinuity studies and find that while regression discontinuity designs are beginning to be utilized in a variety of applications in epidemiology, they are still relatively rare, and analytic and reporting practices vary. Regression discontinuity has the potential to greatly contribute to the evidence base in epidemiology, in particular on the real-life and long-term effects and side-effects of medical treatments that are provided based on threshold rules - such as treatments for low birth weight, hypertension or diabetes.

  1. Differences between Belgian and Brazilian Group A Streptococcus Epidemiologic Landscape

    PubMed Central

    Smeesters, Pierre Robert; Vergison, Anne; Campos, Dioclécio; de Aguiar, Eurico; Deyi, Veronique Yvette Miendje; Van Melderen, Laurence

    2006-01-01

    Background Group A Streptococcus (GAS) clinical and molecular epidemiology varies with location and time. These differences are not or are poorly understood. Methods and Findings We prospectively studied the epidemiology of GAS infections among children in outpatient hospital clinics in Brussels (Belgium) and Brasília (Brazil). Clinical questionnaires were filled out and microbiological sampling was performed. GAS isolates were emm-typed according to the Center for Disease Control protocol. emm pattern was predicted for each isolate. 334 GAS isolates were recovered from 706 children. Skin infections were frequent in Brasília (48% of the GAS infections), whereas pharyngitis were predominant (88%) in Brussels. The mean age of children with GAS pharyngitis in Brussels was lower than in Brasília (65/92 months, p<0.001). emm-typing revealed striking differences between Brazilian and Belgian GAS isolates. While 20 distinct emm-types were identified among 200 Belgian isolates, 48 were found among 128 Brazilian isolates. Belgian isolates belong mainly to emm pattern A–C (55%) and E (42.5%) while emm pattern E (51.5%) and D (36%) were predominant in Brasília. In Brasília, emm pattern D isolates were recovered from 18.5% of the pharyngitis, although this emm pattern is supposed to have a skin tropism. By contrast, A–C pattern isolates were unfrequently recovered in a region where rheumatic fever is still highly prevalent. Conclusions Epidemiologic features of GAS from a pediatric population were very different in an industrialised country and a low incomes region, not only in term of clinical presentation, but also in terms of genetic diversity and distribution of emm patterns. These differences should be taken into account for designing treatment guidelines and vaccine strategies. PMID:17183632

  2. Proceedings of The Second International Molecular Pathological Epidemiology (MPE) Meeting

    PubMed Central

    Ogino, Shuji; Campbell, Peter T.; Nishihara, Reiko; Phipps, Amanda I.; Beck, Andrew H.; Sherman, Mark E.; Chan, Andrew T.; Troester, Melissa A.; Bass, Adam J.; Fitzgerald, Kathryn C.; Irizarry, Rafael A.; Kelsey, Karl T.; Nan, Hongmei; Peters, Ulrike; Poole, Elizabeth M.; Qian, Zhi Rong; Tamimi, Rulla M.; Tchetgen Tchetgen, Eric J.; Tworoger, Shelley S.; Zhang, Xuehong; Giovannucci, Edward L.; van den Brandt, Piet A.; Rosner, Bernard A.; Wang, Molin; Chatterjee, Nilanjan; Begg, Colin B.

    2015-01-01

    Disease classification system increasingly incorporates information on pathogenic mechanisms to predict clinical outcomes and response to therapy and intervention. Technological advancements to interrogate omics (genomics, epigenomics, transcriptomics, proteomics, metabolomics, metagenomics, interactomics, etc.) provide widely-open opportunities in population-based research. Molecular pathological epidemiology (MPE) represents integrative science of molecular pathology and epidemiology. This unified paradigm requires multidisciplinary collaboration between pathology, epidemiology, biostatistics, bioinformatics, and computational biology. Integration of these fields enables better understanding of etiologic heterogeneity, disease continuum, causal inference, and the impact of environment, diet, lifestyle, host factors (including genetics and immunity), and their interactions on disease evolution. Hence, the Second International MPE Meeting was held in Boston in December 2014, with aims to: (1) develop conceptual and practical frameworks; (2) cultivate and expand opportunities; (3) address challenges; and (4) initiate the effort of specifying guidelines for MPE. The meeting mainly consisted of presentations of method developments and recent data in various malignant neoplasms and tumors (breast, prostate, ovarian and colorectal cancers, renal cell carcinoma, lymphoma, and leukemia), followed by open discussion sessions on challenges and future plans. In particular, we recognized need for efforts to further develop statistical methodologies. This meeting provided an unprecedented opportunity for interdisciplinary collaboration, consistent with the purposes of the BD2K (Big Data to Knowledge), GAME-ON (Genetic Associations and Mechanisms in Oncology), and Precision Medicine Initiatives of the U.S.A. National Institute of Health. The MPE Meeting Series can help advance transdisciplinary population science, and optimize training and education systems for 21st century

  3. Epidemiology and management of cardiac arrest: what registries are revealing.

    PubMed

    Gräsner, Jan-Thorsten; Bossaert, Leo

    2013-09-01

    Major European institutions report cardiovascular disease (CVD) as the first cause of death in adults, with cardiac arrest and sudden death due to coronary ischaemia as the primary single cause. Global incidence of CVD is decreasing in most European countries, due to prevention, lifestyle and treatment. Mortality of acute coronary events inside the hospital decreases more rapidly than outside the hospital. To improve the mortality of cardiac arrest outside the hospital, reliable epidemiological and process figures are essential: "we can only manage what we can measure". Europe is a patchwork of 47 countries (total population of 830 million), with a 10-fold difference in incidence of coronary heart disease between North and South, East and West, and a 5-fold difference in number of EMS-treated cardiac arrest (range 17-53/1000,000/year). Epidemiology of cardiac arrest should not be calculated as a European average, but it is appropriate to describe the incidence of cardiac arrest, the resuscitation process, and the outcome in each of the European regions, for benchmarking and quality management. Epidemiological reports of cardiac arrest should specify definitions, nominator (number of cases) and denominator (study population). Recently some regional registries in North America, Japan and Europe fulfilled these conditions. The European Registry of Cardiac Arrest (EuReCa) has the potential to achieve these objectives on a pan-European scale. For operational applications, the Utstein definition of "Cardiac arrest" is used which includes the potential of survival. For application in community health, the WHO definition of "sudden death" is frequently used, describing the mode of death. There is considerable overlap between both definitions. But this explains that no single method can provide all information. Integrating data from multiple sources (local, national, multinational registries and surveys, death certificates, post-mortem reports, community statistics, medical

  4. Shared dosimetry error in epidemiological dose-response analyses

    DOE PAGES

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; ...

    2015-03-23

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takesmore » up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed.« less

  5. Shared Dosimetry Error in Epidemiological Dose-Response Analyses

    SciTech Connect

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre; Zeeb, Hajo

    2015-03-23

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takes up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. Use of these methods for several studies, including the Mayak Worker Cohort and the U.S. Atomic Veterans Study, is discussed.

  6. Shared dosimetry error in epidemiological dose-response analyses

    SciTech Connect

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre; Zeeb, Hajo

    2015-03-23

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takes up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed.

  7. Epidemiology of periodontal diseases in Indian population since last decade

    PubMed Central

    Chandra, Anuja; Yadav, Om Prakash; Narula, Sugandha; Dutta, Angel

    2016-01-01

    Objective: India suffers lot of disparities in terms of oral health care and 95% of the Indian population suffers from periodontal disease. The aim of this review is to estimate the risk factors responsible for periodontal diseases as well as prevalence for the same in the last decade to make an attempt to develop a strategy to improve formulation of an effective oral health care policy in India. Materials and Methods: Keywords such as “prevalence of periodontal diseases,” “epidemiology,” “periodontitis in India,” and “oral hygiene status in India” were searched for appropriate studies to obtain a bibliographic database. The references of selected articles and relevant reviews were searched for any missed publications that included studies conducted in India estimating periodontal diseases with adequate sample size. Clinical parameters, sample size, and findings for each study were tabulated from 2006 to 2015 (till September 15, 2015) in chronological order to observe the prevalence as well as epidemiology of periodontal disease in India. Results: The projection of periodontal disease is disturbing. In addition, the majority of studies done have used the Community Periodontal Index of Treatment Needs (CPITN) as its epidemiological tool that can grossly underestimate the presence of deep pockets. Conclusion: Current knowledge has shown that periodontitis does not present a linear progression and is not age-dependent. Moreover, its distribution and severity are strongly influenced by host susceptibility and risk factors. A structured all-inclusive survey of all districts of the states is a prerequisite for the constitution of an apt and cogent health care policy in our country. PMID:27114945

  8. Shared dosimetry error in epidemiological dose-response analyses.

    PubMed

    Stram, Daniel O; Preston, Dale L; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J; Boice, John; Beck, Harold; Till, John; Bouville, Andre

    2015-01-01

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takes up the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope β is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of β) is biased for β≠0 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the Mayak Worker Cohort, and the U.S. Atomic Veterans Study, is discussed.

  9. Leveraging epidemiologic and clinical collections for genomic studies of complex traits

    PubMed Central

    Crawford, Dana C.; Goodloe, Robert; Farber-Eger, Eric; Boston, Jonathan; Pendergrass, Sarah A.; Haines, Jonathan L.; Ritchie, Marylyn D.; Bush, William S.

    2015-01-01

    Background/Aims Present day limited resources demand DNA and phenotyping alternatives to the traditional prospective population-based epidemiologic collections. Methods To accelerate genomic discovery with an emphasis on diverse populations, we as part of the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed all non-European American samples (n=15,863) available in BioVU, the Vanderbilt University biorepository linked to de-identified electronic medical records, for genomic studies as part of the larger Population Architecture using Genomics and Epidemiology (PAGE) I Study. Given previous studies have cautioned against the secondary use of clinically collected data compared with epidemiologically-collected data, we present here a characterization of EAGLE BioVU, including the billing and diagnostic (ICD-9) code distributions for adult and pediatric patients as well as comparisons made for select health metrics (body mass index, glucose, HbA1c, HDL-C, LDL-C, and triglycerides) with the population-based National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples (NHANES III; n=7,159 and NHANES 1999–2002; n=7,839). Results Overall, the distributions of billing and diagnostic codes suggest this clinical sample is mixture of healthy and sick patients like that expected for a contemporary American population. Conclusion Little bias is observed among health metrics suggesting this clinical collection is suitable for genomic studies along with traditional epidemiologic cohorts. PMID:26201699

  10. Children’s Exposure to Diagnostic Medical Radiation and Cancer Risk: Epidemiologic and Dosimetric Considerations

    PubMed Central

    Linet, Martha S.; Kim, Kwang pyo; Rajaraman, Preetha

    2009-01-01

    While the etiology of most childhood cancers is largely unknown, epidemiologic studies have consistently found an association between exposure to medical radiation during pregnancy and risk of childhood cancer in offspring. The relation between early life diagnostic radiation exposure and occurrence of pediatric cancer risks is less clear. This review summarizes current and historical estimated doses for common diagnostic radiologic procedures as well as the epidemiologic literature on the role of maternal prenatal, children’s postnatal and parental preconception diagnostic radiologic procedures on subsequent risk of childhood malignancies Risk estimates are presented according to factors such as the year of birth of the child, trimester and medical indication for the procedure, and the number of films taken. The paper also discusses limitations of the methods employed in epidemiologic studies to assess pediatric cancer risks, the effects on clinical practice of the results reported from the epidemiologic studies, and clinical and public health policy implications of the findings. Gaps in understanding and additional research needs are identified. Important research priorities include nationwide surveys to estimate fetal and childhood radiation doses from common diagnostic procedures, and epidemiologic studies to quantify pediatric and lifetime cancer risks from prenatal and early childhood exposures to diagnostic radiography, computed tomography, and fluoroscopically-guided procedures. PMID:19083224

  11. Highlights in IBD Epidemiology and Its Natural History in the Paediatric Age

    PubMed Central

    2013-01-01

    Background. The number of patients of all age brackets diagnosed with Inflammatory Bowel Disease (IBD) has risen dramatically worldwide over the past 50 years. IBD's changing epidemiology suggests that environmental factors play a major role in modifying disease expression. Aim. To review studies carried out worldwide analyzing IBD epidemiology. Methods. A Medline search indicating as keywords “Inflammatory Bowel Disease,” “epidemiology,” “natural history,” “Crohn's Disease,” “Ulcerative Colitis,” and “IBD Unclassified” was performed. A selection of clinical cohort and systematic review studies that were carried out between 2002 and 2013 was reviewed. Studies referring to an earlier date were also considered whenever the data were relevant to our review. Results. The current mean prevalence of IBD in the total population of Western countries is estimated at 1/1,000. The highest prevalence and incidence rates of IBD worldwide are reported from Canada. Just as urbanization and socioeconomic development, the incidence of IBD is rising in China. Conclusions. Multicenter national registers and international networks can provide information on IBD epidemiology and lead to hypotheses about its causes and possible management strategies. The rising trend in the disease's incidence in developing nations suggests that its epidemiological evolution is linked to industrialization and modern Westernized lifestyles. PMID:24454343

  12. Epidemiology's contribution to health service management and planning in developing countries: a missing link.

    PubMed Central

    Unger, J. P.; Dujardin, B.

    1992-01-01

    Two hypotheses are examined in the light of experience and the literature: (1) health service planning requires little epidemiological information, and (2) health services rarely get useful answers to relevant epidemiological questions. In the first hypothesis, the theoretical robustness of the concept of a minimum package of activities common to all facilities belonging to the same level of the system and the extent to which it is unaffected by variations in the frequencies of most diseases are examined. Semi-quantitative analyses and analysis of routine entries and participation suffice to adapt this package to the local context. Some of the methods which give a fundamental role to epidemiological information are criticized. With regard to the second hypothesis, the pertinent contributions epidemiology may make to health service organization are reviewed. These include identification of diseases that justify special activities (health maps and interepidemic surveillance), determination of the activities that should be added to the health centres, the political usefulness of rare impact assessments, and the relevant demographic elements. Finally an epidemiological agenda is proposed for specialized centres, districts, universities, and the central decision-making level of health ministries in developing countries. PMID:1394783

  13. Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

    PubMed

    Trinquart, Ludovic; Galea, Sandro

    2015-07-15

    An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field.

  14. [Improving the evaluation of the efficiency of hygiene departments of State Sanitary and Epidemiologic Surveillance Centers].

    PubMed

    Kutsenko, G I; Petruchuk, O E; Beliaev, E N

    2000-01-01

    Methodological, technological, and organization characteristics of efficiency evaluation of specialists and hygienic departments engaged in a State Sanitary Surveillance (SSS) Center of the first level of management are presented. Main notions concerning the efficiency of SSS are formulated. A method for quantitative evaluation of the quality is offered, allowing comparison of compatible and equivalent parameters. Validation for mathematical models of efficiency and quality criteria is offered. Computer technology Sanepidotsenka (Sanitary epidemiological evaluation) is offered, which is used in the regulation of SSS Center activities aimed at maintenance of sanitary and epidemiological well-being of territories.

  15. Forensic Epidemiology: a systematic approach to probabilistic determinations in disputed matters.

    PubMed

    Freeman, Michael D; Rossignol, Annette M; Hand, Michael L

    2008-07-01

    Forensic medicine testimony often relies upon terms of probability to enhance the strength of the testimony. Such terms must have a demonstrably reliable and accurate basis; otherwise their use is speculative, unjustified, and potentially harmful. Forensic Epidemiology is introduced as a framework from which probabilistic testimony can be assessed in settings in which it is either proffered or encountered. In this paper, common forensic uses of probability are reviewed, appropriate methods for presenting such testimony are proposed, and inappropriate uses of probability and epidemiologic concepts and data, as well as a logical fallacies commonly observed in forensic settings are presented. A previously unpublished logical fallacy, the "Prior Odds" Fallacy, is also introduced.

  16. An overview of remote sensing and geodesy for epidemiology and public health application.

    PubMed

    Hay, S I

    2000-01-01

    The techniques of remote sensing (RS) and geodesy have the potential to revolutionize the discipline of epidemiology and its application in human health. As a new departure from conventional epidemiological methods, these techniques require some detailed explanation. This review provides the theoretical background to RS including (i) its physical basis, (ii) an explanation of the orbital characteristics and specifications of common satellite sensor systems, (iii) details of image acquisition and procedures adopted to overcome inherent sources of data degradation, and (iv) a background to geophysical data preparation. This information allows RS applications in epidemiology to be readily interpreted. Some of the techniques used in geodesy, to locate features precisely on Earth so that they can be registered to satellite sensor-derived images, are also included. While the basic principles relevant to public health are presented here, inevitably many of the details must be left to specialist texts.

  17. An Overview of Remote Sensing and Geodesy for Epidemiology and Public Health Application

    PubMed Central

    Hay, S.I.

    2011-01-01

    The techniques of remote sensing (RS) and geodesy have the potential to revolutionize the discipline of epidemiology and its application in human health. As a new departure from conventional epidemiological methods, these techniques require some detailed explanation. This review provides the theoretical background to RS including (i) its physical basis, (ii) an explanation of the orbital characteristics and specifications of common satellite sensor systems, (iii) details of image acquisition and procedures adopted to overcome inherent sources of data degradation, and (iv) a background to geophysical data preparation. This information allows RS applications in epidemiology to be readily interpreted. Some of the techniques used in geodesy, to locate features precisely on Earth so that they can be registered to satellite sensor-derived images, are also included. While the basic principles relevant to public health are presented here, inevitably many of the details must be left to specialist texts. PMID:10997203

  18. Tropical epidemiology: a system for continuous demographic monitoring of a study population.

    PubMed

    Stephens, J; Alonso, P L; Byass, P; Snow, R W

    1989-07-01

    Epidemiologists in many developing countries, where official demographic services are unavailable, have to include some demographic functions in their work. The usual method of documenting a study population for epidemiological research in a developing country consists of three stages: mapping, enumeration and vital registration. This paper considers the last element of this process, detailing the development of a suitable data system and explaining how its implementation using microcomputers and a database management system can help in the creation of an on-line continuous vital registration system for a study population as an epidemiological tool. The issues covered are data collection, entry and analysis, and the advantages of such a system for use in epidemiological research in developing countries are also discussed.

  19. Antibodies in crevicular fluid: an epidemiological tool for investigation of waterborne disease.

    PubMed

    Gammie, A; Morris, R; Wyn-Jones, A P

    2002-04-01

    A significant challenge in the epidemiological investigation of recreational waterborne disease is the establishment of a definite association between exposure to a contaminated water and infection. An increase in specific antibodies as a result of infection is a potent measure of disease exposure and its determination would enhance epidemiological studies of waterborne diseases. We report on the automated detection of HAV antibodies in crevicular fluid and its use in a field study. The method is easy to use, non-invasive, could be applied to volunteers of all ages and is comparable in sensitivity to serological procedures. Application to an epidemiological study of water recreationalists demonstrated that surfers were three times more likely to be immune to hepatitis A virus than either wind-surfers or a control group without recreational water contact.

  20. Polyfluoroalkyl Chemicals and Learning and Developmental Disorders: Epidemiology and Exposure Assessment

    ERIC Educational Resources Information Center

    Hoffman, Jennifer Kate

    2010-01-01

    This dissertation has two areas of focus: learning and developmental disorders (LDDs) and polyfluoroalkyl chemicals (PFCs). Epidemiological and exposure assessment methods are applied to each. The first paper used geographic location as a surrogate for exposure and broadly assesses the effect of the environment, both physical and social, on LDD…