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Sample records for epidemiologic methods

  1. Epidemiology and the scientific method.

    PubMed

    Chalmers, A F

    1982-01-01

    This article refutes the claim that the field of epidemiology and community health would benefit from the application of the scientific method. It is argued that the methods of physics are not appropriate for other disciplines. When applied to the social sciences, positivism is a conservatizing force, causing theory to become based on a mere description of social phenomenon. Since it cannot lead to a deep understanding of social phenomena, positivism is incapable of revealing ways in which society could be radically changed. Moreover, such theory is far from neutral. Rather, it is formed and influenced by the forms of life experienced and practiced in the society. This is illustrated by an analysis of the origin of modern physics at the time when society was changing from a feudal to capitalist form of organization. It is concluded that advances will be made in epidemiology and community health when this field breaks from its focus on the individual and incorporates class into its analysis. However, given the interconnection between social structure and social theory, resistance to such a radical change can be expected. PMID:7141777

  2. Advanced epidemiologic and analytical methods.

    PubMed

    Albanese, E

    2016-01-01

    Observational studies are indispensable for etiologic research, and are key to test life-course hypotheses and improve our understanding of neurologic diseases that have long induction and latency periods. In recent years a plethora of advanced design and analytic techniques have been developed to strengthen the robustness and ultimately the validity of the results of observational studies, and to address their inherent proneness to bias. It is the responsibility of clinicians and researchers to critically appraise and appropriately contextualize the findings of the exponentially expanding scientific literature. This critical appraisal should be rooted in a thorough understanding of advanced epidemiologic methods and techniques commonly used to formulate and test relevant hypotheses and to keep bias at bay. PMID:27637951

  3. 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.

  4. Kinetics methods for clinical epidemiology problems

    PubMed Central

    Corlan, Alexandru Dan; Ross, John

    2015-01-01

    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. PMID:26578757

  5. 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.

  6. A Review of Spatial Methods in Epidemiology, 2000–2010

    PubMed Central

    Auchincloss, Amy H.; Gebreab, Samson Y.; Mair, Christina; Roux, Ana V. Diez

    2013-01-01

    Understanding the impact of place on health is a key element of epidemiologic investigation, and numerous tools are being employed for analysis of spatial health-related data. This review documents the huge growth in spatial epidemiology, summarizes the tools that have been employed, and provides in-depth discussion of several methods. Relevant research articles for 2000–2010 from seven epidemiology journals were included if the study utilized a spatial analysis method in primary analysis (n = 207). Results summarized frequency of spatial methods and substantive focus; graphs explored trends over time. The most common spatial methods were distance calculations, spatial aggregation, clustering, spatial smoothing and interpolation, and spatial regression. Proximity measures were predominant and were applied primarily to air quality and climate science and resource access studies. The review concludes by noting emerging areas that are likely to be important to future spatial analysis in public health. PMID:22429160

  7. Epidemiological designs for vaccine safety assessment: methods and pitfalls.

    PubMed

    Andrews, Nick

    2012-09-01

    Three commonly used designs for vaccine safety assessment post licensure are cohort, case-control and self-controlled case series. These methods are often used with routine health databases and immunisation registries. This paper considers the issues that may arise when designing an epidemiological study, such as understanding the vaccine safety question, case definition and finding, limitations of data sources, uncontrolled confounding, and pitfalls that apply to the individual designs. The example of MMR and autism, where all three designs have been used, is presented to help consider these issues. PMID:21985898

  8. Epidemiological designs for vaccine safety assessment: methods and pitfalls.

    PubMed

    Andrews, Nick

    2012-09-01

    Three commonly used designs for vaccine safety assessment post licensure are cohort, case-control and self-controlled case series. These methods are often used with routine health databases and immunisation registries. This paper considers the issues that may arise when designing an epidemiological study, such as understanding the vaccine safety question, case definition and finding, limitations of data sources, uncontrolled confounding, and pitfalls that apply to the individual designs. The example of MMR and autism, where all three designs have been used, is presented to help consider these issues.

  9. A method for meta-analysis of epidemiological studies.

    PubMed

    Einarson, T R; Leeder, J S; Koren, G

    1988-10-01

    This article presents a stepwise approach for conducting a meta-analysis of epidemiological studies based on proposed guidelines. This systematic method is recommended for practitioners evaluating epidemiological studies in the literature to arrive at an overall quantitative estimate of the impact of a treatment. Bendectin is used as an illustrative example. Meta-analysts should establish a priori the purpose of the analysis and a complete protocol. This protocol should be adhered to, and all steps performed should be recorded in detail. To aid in developing such a protocol, we present methods the researcher can use to perform each of 22 steps in six major areas. The illustrative meta-analysis confirmed previous traditional narrative literature reviews that Bendectin is not related to teratogenic outcomes in humans. The overall summary odds ratio was 1.01 (chi 2 = 0.05, p = 0.815) with a 95 percent confidence interval of 0.66-1.55. When the studies were separated according to study type, the summary odds ratio for cohort studies was 0.95 with a 95 percent confidence interval of 0.62-1.45. For case-control studies, the summary odds ratio was 1.27 with a 95 percent confidence interval of 0.83-1.94. The corresponding chi-square values were not statistically significant at the p = 0.05 level.

  10. The science of epidemiology and the methods needed for public health assessments: a review of epidemiology textbooks

    PubMed Central

    2014-01-01

    Objectives Epidemiology is often described as ‘the science of public health’. Here we aim to assess the extent that epidemiological methods, as covered in contemporary standard textbooks, provide tools that can assess the relative magnitude of public health problems and can be used to help rank and assess public health priorities. Study Design Narrative literature review. Methods Thirty textbooks were grouped into three categories; pure, extended or applied epidemiology, were reviewed with attention to the ways the discipline is characterised and the nature of the analytical methods described. Results Pure texts tend to present a strict hierarchy of methods with those metrics deemed to best serve aetiological inquiry at the top. Extended and applied texts employ broader definitions of epidemiology but in most cases, the metrics described are also those used in aetiological inquiry and may not be optimal for capturing the consequences and social importance of injuries and disease onsets. Conclusions The primary scientific purpose of epidemiology, even amongst ‘applied’ textbooks, is aetiological inquiry. Authors do not readily extend to methods suitable for assessing public health problems and priorities. PMID:24507570

  11. Blastocystis: Genetic diversity and molecular methods for diagnosis and epidemiology.

    PubMed

    Stensvold, Christen Rune

    2013-01-01

    Blastocystis, an unusual anaerobic, single-celled stramenopile, is a remarkably successful intestinal parasite of a vast array of host species including humans. Fecal Deoxyribonucleic acid (DNA) analysis by nucleic-acid based methods in particular has led to significant advances in Blastocystis diagnostics and research over the past few years enabling accurate identification of carriers and molecular characterization by high discriminatory power. Moreover, Blastocystis comprises a multitude of subtypes (STs) (arguably species) many of which have been identified only recently and molecular epidemiological studies have revealed a significant difference in the distribution of STs across host species and geographical regions. Having a cosmopolitan distribution, the parasite is a common laboratory finding in the stools of individuals with and without intestinal symptoms across the entire globe and while the parasite remains extremely difficult to eradicate and isolate in culture, appropriate molecular tools are now available to resolve important questions such as whether the clinical outcome of colonization is linked to ST and whether Blastocystis is transmitted zoonotically. This review summarizes some of the recent advances in the molecular diagnosis of Blastocystis and gives an introduction to Blastocystis STs, including a recommendation of subtyping methodology based on recent data and method comparisons. A few suggestions for future directions and research areas are given in the light of relevant technological advances and the availability of mitochondrial and nuclear genomes.

  12. 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…

  13. Epidemiological methods in diarrhoea studies—an update

    PubMed Central

    Schmidt, Wolf-Peter; Arnold, Benjamin F; Boisson, Sophie; Genser, Bernd; Luby, Stephen P; Barreto, Mauricio L; Clasen, Thomas; Cairncross, Sandy

    2011-01-01

    Background Diarrhoea remains a leading cause of morbidity and mortality but is difficult to measure in epidemiological studies. Challenges include the diagnosis based on self-reported symptoms, the logistical burden of intensive surveillance and the variability of diarrhoea in space, time and person. Methods We review current practices in sampling procedures to measure diarrhoea, and provide guidance for diarrhoea measurement across a range of study goals. Using 14 available data sets, we estimated typical design effects for clustering at household and village/neighbourhood level, and measured the impact of adjusting for baseline variables on the precision of intervention effect estimates. Results Incidence is the preferred outcome measure in aetiological studies, health services research and vaccine trials. Repeated prevalence measurements (longitudinal prevalence) are appropriate in high-mortality settings where malnutrition is common, although many repeat measures are rarely useful. Period prevalence is an inadequate outcome if an intervention affects illness duration. Adjusting point estimates for age or diarrhoea at baseline in randomized trials has little effect on the precision of estimates. Design effects in trials randomized at household level are usually <2 (range 1.0–3.2). Design effects for larger clusters (e.g. villages or neighbourhoods) vary greatly among different settings and study designs (range 0.1–25.8). Conclusions Using appropriate sampling strategies and outcome measures can improve the efficiency, validity and comparability of diarrhoea studies. Allocating large clusters in cluster randomized trials is compromized by unpredictable design effects and should be carried out only if the research question requires it. PMID:22268237

  14. 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. PMID:24942564

  15. 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

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

    PubMed Central

    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.

    2015-01-01

    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

  17. 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

  18. 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

  19. 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

    2016-01-01

    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

  20. Overview of molecular typing methods for outbreak detection and epidemiological surveillance.

    PubMed

    Sabat, A J; Budimir, A; Nashev, D; Sá-Leão, R; van Dijl, J m; Laurent, F; Grundmann, H; Friedrich, A W

    2013-01-01

    Typing methods for discriminating different bacterial isolates of the same species are essential epidemiological tools in infection prevention and control. Traditional typing systems based on phenotypes, such as serotype, biotype, phage-type, or antibiogram, have been used for many years. However, more recent methods that examine the relatedness of isolates at a molecular level have revolutionised our ability to differentiate among bacterial types and subtypes. Importantly, the development of molecular methods has provided new tools for enhanced surveillance and outbreak detection. This has resulted in better implementation of rational infection control programmes and efficient allocation of resources across Europe. The emergence of benchtop sequencers using next generation sequencing technology makes bacterial whole genome sequencing (WGS) feasible even in small research and clinical laboratories. WGS has already been used for the characterisation of bacterial isolates in several large outbreaks in Europe and, in the near future, is likely to replace currently used typing methodologies due to its ultimate resolution. However, WGS is still too laborious and time-consuming to obtain useful data in routine surveillance. Also, a largely unresolved question is how genome sequences must be examined for epidemiological characterisation. In the coming years, the lessons learnt from currently used molecular methods will allow us to condense the WGS data into epidemiologically useful information. On this basis, we have reviewed current and new molecular typing methods for outbreak detection and epidemiological surveillance of bacterial pathogens in clinical practice, aiming to give an overview of their specific advantages and disadvantages. PMID:23369389

  1. Outcome modelling strategies in epidemiology: traditional methods and basic alternatives.

    PubMed

    Greenland, Sander; Daniel, Rhian; Pearce, Neil

    2016-04-01

    Controlling for too many potential confounders can lead to or aggravate problems of data sparsity or multicollinearity, particularly when the number of covariates is large in relation to the study size. As a result, methods to reduce the number of modelled covariates are often deployed. We review several traditional modelling strategies, including stepwise regression and the 'change-in-estimate' (CIE) approach to deciding which potential confounders to include in an outcome-regression model for estimating effects of a targeted exposure. We discuss their shortcomings, and then provide some basic alternatives and refinements that do not require special macros or programming. Throughout, we assume the main goal is to derive the most accurate effect estimates obtainable from the data and commercial software. Allowing that most users must stay within standard software packages, this goal can be roughly approximated using basic methods to assess, and thereby minimize, mean squared error (MSE).

  2. Outcome modelling strategies in epidemiology: traditional methods and basic alternatives

    PubMed Central

    Greenland, Sander; Daniel, Rhian; Pearce, Neil

    2016-01-01

    Controlling for too many potential confounders can lead to or aggravate problems of data sparsity or multicollinearity, particularly when the number of covariates is large in relation to the study size. As a result, methods to reduce the number of modelled covariates are often deployed. We review several traditional modelling strategies, including stepwise regression and the ‘change-in-estimate’ (CIE) approach to deciding which potential confounders to include in an outcome-regression model for estimating effects of a targeted exposure. We discuss their shortcomings, and then provide some basic alternatives and refinements that do not require special macros or programming. Throughout, we assume the main goal is to derive the most accurate effect estimates obtainable from the data and commercial software. Allowing that most users must stay within standard software packages, this goal can be roughly approximated using basic methods to assess, and thereby minimize, mean squared error (MSE). PMID:27097747

  3. 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

  4. Comparison of methods of extracting information for meta-analysis of observational studies in nutritional epidemiology

    PubMed Central

    2016-01-01

    OBJECTIVES: A common method for conducting a quantitative systematic review (QSR) for observational studies related to nutritional epidemiology is the “highest versus lowest intake” method (HLM), in which only the information concerning the effect size (ES) of the highest category of a food item is collected on the basis of its lowest category. However, in the interval collapsing method (ICM), a method suggested to enable a maximum utilization of all available information, the ES information is collected by collapsing all categories into a single category. This study aimed to compare the ES and summary effect size (SES) between the HLM and ICM. METHODS: A QSR for evaluating the citrus fruit intake and risk of pancreatic cancer and calculating the SES by using the HLM was selected. The ES and SES were estimated by performing a meta-analysis using the fixed-effect model. The directionality and statistical significance of the ES and SES were used as criteria for determining the concordance between the HLM and ICM outcomes. RESULTS: No significant differences were observed in the directionality of SES extracted by using the HLM or ICM. The application of the ICM, which uses a broader information base, yielded more-consistent ES and SES, and narrower confidence intervals than the HLM. CONCLUSIONS: The ICM is advantageous over the HLM owing to its higher statistical accuracy in extracting information for QSR on nutritional epidemiology. The application of the ICM should hence be recommended for future studies. PMID:26797219

  5. 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

  6. Meticillin-resistant Staphylococcus aureus (MRSA): global epidemiology and harmonisation of typing methods.

    PubMed

    Stefani, Stefania; Chung, Doo Ryeon; Lindsay, Jodi A; Friedrich, Alex W; Kearns, Angela M; Westh, Henrik; Mackenzie, Fiona M

    2012-04-01

    This article reviews recent findings on the global epidemiology of healthcare-acquired/associated (HA), community-acquired/associated (CA) and livestock-associated (LA) meticillin-resistant Staphylococcus aureus (MRSA) and aims to reach a consensus regarding the harmonisation of typing methods for MRSA. MRSA rates continue to increase rapidly in many regions and there is a dynamic spread of strains across the globe. HA-MRSA is currently endemic in hospitals in most regions. CA-MRSA clones have been spreading rapidly in the community and also infiltrating healthcare in many regions worldwide. To date, LA-MRSA is only prevalent in certain high-risk groups of workers in direct contact with live animals. CA-MRSA and LA-MRSA have become a challenge for countries that have so far maintained low rates of MRSA. These evolutionary changes have resulted in MRSA continuing to be a major threat to public health. Continuous efforts to understand the changing epidemiology of S. aureus infection in humans and animals are therefore necessary, not only for appropriate antimicrobial treatment and effective infection control but also to monitor the evolution of the species. The group made several consensus decisions with regard to harmonisation of typing methods. A stratified, three-level organisation of testing laboratories was proposed: local; regional; and national. The functions of, and testing methodology used by, each laboratory were defined. The group consensus was to recommend spa and staphylococcal cassette chromosome mec (SCCmec) typing as the preferred methods. Both are informative in defining particular strain characteristics and utilise standardised nomenclatures, making them applicable globally. Effective communication between each of the different levels and between national centres was viewed as being crucial to inform and monitor the molecular epidemiology of MRSA at national and international levels.

  7. Epidemiologic Treatment in Venereal Disease—A Method to Aid in VD Control

    PubMed Central

    Mitchell, Ellis N.

    1972-01-01

    Epidemiologic therapy refers to the treatment of infectious syphilis or gonorrhea contacts without proof of laboratory diagnosis. This method of treatment is considered essential by public health authorities in the management of venereal disease, but has long been neglected in the private sector of medicine. The majority of venereal disease patients are treated by private practitioners, but apathetic attitudes, insufficient training, lack of case reporting, differing and often inadequate treatment schedules, poor follow-up and ignorance about or reluctance to use epi-treatment are all factors in our losing struggle against the current venereal disease epidemic. PMID:4635397

  8. [Secondary adentia and dental implantation (epidemiological and sociological study by a telephone interview method)].

    PubMed

    Fediaev, I M; Khamadeeva, A M; Nikol'skiĭ, V Iu; Ganzha, I R

    2004-01-01

    Epidemiological research of partial secondary adentia was done by means of telephone interviewing the population of city of Samara (1104 persons are interrogated). Prevalence and intensity of the disease in various age groups, and also average indices for all adult population are established. The share of the persons requiring for dental prosthetics among patients with defects of dental lines is determined. The same method investigates awareness of the population about dental implantation, and also the estimation is given to public opinion on treatment with the use of implants.

  9. 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.

  10. Diagnostic electrocardiography in epidemiological studies of Chagas' disease: multicenter evaluation of a standardized method.

    PubMed

    Lázzari, J O; Pereira, M; Antunes, C M; Guimarães, A; Moncayo, A; Chávez Domínguez, R; Hernández Pieretti, O; Macedo, V; Rassi, A; Maguire, J; Romero, A

    1998-11-01

    An electrocardiographic recording method with an associated reading guide, designed for epidemiological studies on Chagas' disease, was tested to assess its diagnostic reproducibility. Six cardiologists from five countries each read 100 electrocardiographic (ECG) tracings, including 30 from chronic chagasic patients, then reread them after an interval of 6 months. The readings were blind, with the tracings numbered randomly for the first reading and renumbered randomly for the second reading. The physicians, all experienced in interpreting ECGs from chagasic patients, followed printed instructions for reading the tracings. Reproducibility of the readings was evaluated using the kappa (kappa) index for concordance. The results showed a high degree of interobserver concordance with respect to the diagnosis of normal vs. abnormal tracings (kappa = 0.66; SE 0.02). While the interpretations of some categories of ECG abnormalities were highly reproducible, others, especially those having a low prevalence, showed lower levels of concordance. Intraobserver concordance was uniformly higher than interobserver concordance. The findings of this study justify the use by specialists of the recording of readings method proposed for epidemiological studies on Chagas' disease, but warrant caution in the interpretation of some categories of electrocardiographic alterations.

  11. 10-Year Research Update Review: The Epidemiology of Child and Adolescent Psychiatric Disorders--I. Methods and Public Health Burden

    ERIC Educational Resources Information Center

    Costello, E. Jane; Egger, Helen; Angold, Adrian

    2005-01-01

    Objective: To review recent progress in child and adolescent psychiatric epidemiology in the area of prevalence and burden. Method: The literature published in the past decade was reviewed under two headings: methods and findings. Results: Methods for assessing the prevalence and community burden of child and adolescent psychiatric disorders have…

  12. 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

  13. 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. 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. Current Methods and Challenges for Epidemiological Studies of the Associations Between Chemical Constituents of Particulate Matter and Health.

    PubMed

    Krall, Jenna R; Chang, Howard H; Sarnat, Stefanie Ebelt; Peng, Roger D; Waller, Lance A

    2015-12-01

    Epidemiological studies have been critical for estimating associations between exposure to ambient particulate matter (PM) air pollution and adverse health outcomes. Because total PM mass is a temporally and spatially varying mixture of constituents with different physical and chemical properties, recent epidemiological studies have focused on PM constituents. Most studies have estimated associations between PM constituents and health using the same statistical methods as in studies of PM mass. However, these approaches may not be sufficient to address challenges specific to studies of PM constituents, namely assigning exposure, disentangling health effects, and handling measurement error. We reviewed large, population-based epidemiological studies of PM constituents and health and describe the statistical methods typically applied to address these challenges. Development of statistical methods that simultaneously address multiple challenges, for example, both disentangling health effects and handling measurement error, could improve estimation of associations between PM constituents and adverse health outcomes.

  16. [Retrospective evaluation of occupational exposure in epidemiologic studies. Use of the Delphi method].

    PubMed

    Goldberg, M; Leclerc, A; Chastang, J F; Goldberg, P; Brodeur, J M; Fuhrer, R; Segnan, N

    1986-01-01

    A method, based on the Delphi technique, for evaluating occupational risks in a quantifiable manner was devised in the course of a case-control study on respiratory cancers in the nickel mining and refining industry in New Caledonia. There were four stages in the evaluation process: identification of eleven potential carcinogenic factors in the company during the 1930-1977 period; grouping of a limited number of work-stations; evaluation of exposure levels for the different factors for each workstation; computation of the cumulative value of exposure for each subject under study. A partial validation study shows that this kind of approach may prove useful for future occupational epidemiological studies. PMID:3547516

  17. 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

  18. [Field epidemiology and social epidemiology].

    PubMed

    Segura del Pozo, Javier

    2006-01-01

    Comparing field epidemiology and social epidemiology, we pretend to think about the no explicit images and meanings operating in both necessary convergent fields, about the obstacles present in epidemiological practice to fulfil its social function and about the necessity of changing epistemological, methodological and practice grounds, beginning with field epidemiologists teaching programmes. Field epidemiology would tend to act in an absent theoretical frame. On the other hand, social epidemiology would tend to prioritize theoretical developments (thinking and research about social determinants) without correspondent action, because of the limits to change public policies. Other differences are found at intervention level (micro-macrospace), its aim (outbreak control vs. inequalities control) and the way to communicate with society. They are similar in the methodological concern, the predominance of orientation based on positivism and framed through statistic methods, but in process of epistemological opening, the stress experienced between the alternative relationship to a virtual world of data bases or to the real society, their peripherical situation in relation of the political, social, institutional and professional system and the tendency to professional frustration. Finally, we ask ten questions to the field epidemiologists related with their present practice, in order to consider if they are developing social epidemiology, and propose some changes in epidemiologist teaching and practice.

  19. Validation of Simple Epidemiological or Clinical Methods for the Measurement of Body Composition in Young Children

    PubMed Central

    Jackson, Diane M; Donaghy, Zoe; Djafarian, Kurosh; Reilly, John J

    2014-01-01

    Objective: The present study aimed to determine the validity of simple epidemiological and clinical methods for the assessment of body fatness in preschool children. Methods: In 89 children (42 boys, 47 girls; mean age 4.1 SD 1.3y) measures of body fatness were made using total body water (TBW), dual energy x-ray absorptiometry (DXA), air displacement plethysmography (BODPOD) and skinfold thickness. Methods were compared by Bland–Altman analysis using TBW as the reference method, and by paired comparisons and rank order correlations. Findings: Bias for DXA was +1.8% body fat percentage units (limits of agreement +15.5% to −11.9%), bias for BODPOD was −3.5% (limits of agreement +18.9% to −5.9%) and bias for skinfolds using the Slaughter equations was −6.5% (limits of agreement +10.0% to −23.1%). Significant rank order correlations with TBW measures of fatness were obtained for DXA estimates of fatness (r=0.54, P=0.01), but not for estimates of fat by skinfold thickness (r=0.20, P=0.2) or BODPOD (r=0.25, P=0.1). Differences between both DXA and BODPOD and the reference TBW estimates of body fatness were not significant (P=0.06 and P=0.1 respectively); however, the difference in estimated body fatness between skinfold thickness and TBW was significant (P<0.001). Conclusion: Estimates of body fatness in preschool children were inaccurate at the level of the individual child using all the methods, but DXA might provide unbiased estimates and a means of making relative assessments of body fatness. PMID:26019772

  20. 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

  1. [Occupational epidemiology].

    PubMed

    Ahrens, W; Behrens, T; Mester, B; Schmeisser, N

    2008-03-01

    The aim of occupational epidemiology is to describe workplace-related diseases and to identify their underlying causes. Its primary goal is to protect workers from hazardous effects of the working process by applying work-related primary and secondary prevention measures. To assess health risks different study designs and a wide array of complex study instruments and methods are frequently employed that cannot be replaced by toxicological investigations. This paper primarily addresses health risks by agent exposures. In this context a central task of occupational epidemiology is careful assessment of exposure. Different data sources, such as work site measurements, register data, archive material, experts' opinion, and the workers' personal estimates of exposure may be used during this process. In addition, biological markers can complement exposure assessment. Since thorough occupational epidemiologic studies allow assessment of disease risks under realistic exposure conditions, their results should be more frequently used to derive workplace-related threshold limit values. PMID:18311483

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Statistical methods in public health and epidemiology: a look at the recent past and projections for the next decade.

    PubMed

    Levy, P S; Stolte, K

    2000-02-01

    This article attempts to prognosticate from past patterns, the type of statistical methods that will be used in published public health and epidemiological studies in the decade that follows the millennium. With this in mind, we conducted a study that would characterize trends in use of statistical methods in two major public health journals: the American Journal of Public Health, and the American Journal of Epidemiology. We took a probability sample of 348 articles published in these journals between 1970 and 1998. For each article sampled, we abstracted information on the design of the study and the types of statistical methods used in the article. Our major findings are that the proportion of articles using statistical methods as well as the mean number of statistical methods used per article has increased dramatically over the three decades surveyed. Also, the proportion of published articles using study designs that we classified as analytic has increased over the years. We also examined patterns of use in these journals of three statistical methodologies: logistic regression, proportional hazards regression, and methods for analysis of data from complex sample surveys. These methods were selected because they had been introduced initially in the late 1960s or early 1970s and had made considerable impact on data analysis in the biomedical sciences in the 1970s-90s. Estimated usage of each of these techniques remained relatively low until user-friendly software became available. Our overall conclusions are that new statistical methods are developed on the basis of need, disseminated to potential users over a course of many years, and often do not reach maximum use until tools for their comfortable use are made readily available to potential users. Based on these conclusions, we identify certain needs that are not now being met and which are likely to generate new statistical methodologies that we will see in the next decade.

  8. Foot-and-mouth disease in pigs: current epidemiological situation and control methods.

    PubMed

    León, Emilio A

    2012-03-01

    Foot-and-mouth disease (FMD) is the paradigm of a transboundary animal disease. Beyond any doubt, it is the most serious challenge for livestock's health. Official Veterinary Services from free countries invest considerable amount of money to prevent its introduction, whereas those from endemic countries invest most of their resources in the control of the disease. A very important volume of scientific production is developed every year in different aspects of FMD, and for that reason, the current knowledge makes the diagnosis of the disease easier to a great extent. However, FMD is still endemic in about two-thirds of the countries, and periodically re-emergent in several countries. This paper is a review of recent publications, focusing mainly on control measures and current world epidemiological situation, emphasizing primarily pigs. PMID:22225815

  9. 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.

  10. 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.

  11. Three-area epidemiological study of geographic differences in stroke mortality. I. Background and methods.

    PubMed

    Nefzger, M D; Kuller, L H; Lilienfeld, A M; Diamond, E L; Miller, G D; Stolley, P D; Tonascia, S

    1977-01-01

    An epidemiological study was conducted to determine the geographical variations in stroke mortality among three U.S. areas. They were Savannah, Georgia (high stroke rates), Hagerstown, Maryland (intermediate stroke rates) and Pueblo, Colorado (low stroke rates). In each area samples were drawn of the population in the 35--54 age group. The subjects were interviewed and examined to obtain the information required on medical conditions and/or living habits which would characterize each area. A brief medical and family history, as well as demographic and personal data, were obtained by interview. The medical examination included blood pressure, ECG, blood and urine chemistry, height and weight. In all three cities the response rate in the final sample selected was 90% (2,375 individuals) interviewed and 74% (1.939 individuals) examined.

  12. 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

  13. Circular epidemiology.

    PubMed

    Kuller, L H

    1999-11-01

    Circular epidemiology can be defined as the continuation of specific types of epidemiologic studies beyond the point of reasonable doubt of the true existence of an important association or the absence of such an association. Circular epidemiology is an extreme example of studies of the consistency of associations. A basic problem for epidemiology is the lack of a systematic approach to acquiring new knowledge to reach a goal of improving public health and preventive medicine. For epidemiologists, research support unfortunately is biased toward the continued study of already proven hypotheses. Circular epidemiology, however, freezes at one point in the evolution of epidemiologic studies, failing to move from descriptive to analytical case-control and longitudinal studies, for example, to experimental, clinical trials. Good epidemiology journals are filled with very well-conducted epidemiologic studies that primarily repeat the obvious or are variations on the theme.

  14. 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

  15. Genetic epidemiology utilizing the adoption method: studies of obesity and of premature death in adults.

    PubMed

    Sørensen, T I

    1991-03-01

    Genetic epidemiology gives no priority to genes or environment in the search of disease causation. However, a major problem in this field is the disentangling of the effects of environment and genes. The study of subjects separated very early in life from their biologic parents and adopted by unrelated parents provide a strong tool for estimation of genetic and familial environmental influences. The degree to which the trait or disease frequency of the adoptees is similar to that seen among the biologic relatives is an indication of the strength of the genetic influence. Similarity to the adoptive relatives suggests influences of the family environment shared between them. Adoption studies of adult obesity show that it is genes, and not the family environment, that is responsible for the familial aggregation of obesity. A study of the mortality of adult adoptees and their biologic and adoptive parents indicates a genetic influence on the risk of premature death from all causes, from natural causes, infections, and cardio- and cerebrovascular conditions, and suggests familial environmental influences on death from the vascular causes and from cancer.

  16. Measuring sun exposure in epidemiological studies: Matching the method to the research question.

    PubMed

    King, Laura; Xiang, Fan; Swaminathan, Ashwin; Lucas, Robyn M

    2015-12-01

    Sun exposure has risks and benefits for health. Testing these associations requires tools for measuring sun exposure that are feasible and relevant to the time-course of the health outcome. Recent sun exposure, e.g. the last week, is best captured by dosimeters and sun diaries. These can also be used for medium-term sun exposure e.g. over several weeks, but incur a high participant burden. Self-reported data on "typical time outdoors" for working and non-working days, is less detailed and not influenced by day-to-day variation. Over a longer period, e.g. the lifetime, or for particular life stages, proxies of sun exposure, such as latitude of residence or ambient ultraviolet (UV) radiation levels (from satellites or ground-level monitoring) can be used, with additional detail provided by lifetime sun exposure calendars that include locations of residence, usual time outdoors, and detail of sunburn episodes. Objective measures of lifetime sun exposure include microtopography of sun-exposed skin (e.g. using silicone casts) or conjunctival UV autofluorescence. Potential modifiers of the association between sun exposure and the health outcome, such as clothing coverage and skin colour, may also need to be measured. We provide a systematic approach to selecting sun exposure measures for use in epidemiological health research.

  17. Measuring sun exposure in epidemiological studies: Matching the method to the research question.

    PubMed

    King, Laura; Xiang, Fan; Swaminathan, Ashwin; Lucas, Robyn M

    2015-12-01

    Sun exposure has risks and benefits for health. Testing these associations requires tools for measuring sun exposure that are feasible and relevant to the time-course of the health outcome. Recent sun exposure, e.g. the last week, is best captured by dosimeters and sun diaries. These can also be used for medium-term sun exposure e.g. over several weeks, but incur a high participant burden. Self-reported data on "typical time outdoors" for working and non-working days, is less detailed and not influenced by day-to-day variation. Over a longer period, e.g. the lifetime, or for particular life stages, proxies of sun exposure, such as latitude of residence or ambient ultraviolet (UV) radiation levels (from satellites or ground-level monitoring) can be used, with additional detail provided by lifetime sun exposure calendars that include locations of residence, usual time outdoors, and detail of sunburn episodes. Objective measures of lifetime sun exposure include microtopography of sun-exposed skin (e.g. using silicone casts) or conjunctival UV autofluorescence. Potential modifiers of the association between sun exposure and the health outcome, such as clothing coverage and skin colour, may also need to be measured. We provide a systematic approach to selecting sun exposure measures for use in epidemiological health research. PMID:26555640

  18. 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

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

    PubMed

    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

  20. Review and International Recommendation of Methods for Typing Neisseria gonorrhoeae Isolates and Their Implications for Improved Knowledge of Gonococcal Epidemiology, Treatment, and Biology

    PubMed Central

    Unemo, Magnus; Dillon, Jo-Anne R.

    2011-01-01

    Summary: Gonorrhea, which may become untreatable due to multiple resistance to available antibiotics, remains a public health problem worldwide. Precise methods for typing Neisseria gonorrhoeae, together with epidemiological information, are crucial for an enhanced understanding regarding issues involving epidemiology, test of cure and contact tracing, identifying core groups and risk behaviors, and recommending effective antimicrobial treatment, control, and preventive measures. This review evaluates methods for typing N. gonorrhoeae isolates and recommends various methods for different situations. Phenotypic typing methods, as well as some now-outdated DNA-based methods, have limited usefulness in differentiating between strains of N. gonorrhoeae. Genotypic methods based on DNA sequencing are preferred, and the selection of the appropriate genotypic method should be guided by its performance characteristics and whether short-term epidemiology (microepidemiology) or long-term and/or global epidemiology (macroepidemiology) matters are being investigated. Currently, for microepidemiological questions, the best methods for fast, objective, portable, highly discriminatory, reproducible, typeable, and high-throughput characterization are N. gonorrhoeae multiantigen sequence typing (NG-MAST) or full- or extended-length porB gene sequencing. However, pulsed-field gel electrophoresis (PFGE) and Opa typing can be valuable in specific situations, i.e., extreme microepidemiology, despite their limitations. For macroepidemiological studies and phylogenetic studies, DNA sequencing of chromosomal housekeeping genes, such as multilocus sequence typing (MLST), provides a more nuanced understanding. PMID:21734242

  1. Fast and simple epidemiological typing of Pseudomonas aeruginosa using the double-locus sequence typing (DLST) method.

    PubMed

    Basset, P; Blanc, D S

    2014-06-01

    Although the molecular typing of Pseudomonas aeruginosa is important to understand the local epidemiology of this opportunistic pathogen, it remains challenging. Our aim was to develop a simple typing method based on the sequencing of two highly variable loci. Single-strand sequencing of three highly variable loci (ms172, ms217, and oprD) was performed on a collection of 282 isolates recovered between 1994 and 2007 (from patients and the environment). As expected, the resolution of each locus alone [number of types (NT) = 35-64; index of discrimination (ID) = 0.816-0.964] was lower than the combination of two loci (NT = 78-97; ID = 0.966-0.971). As each pairwise combination of loci gave similar results, we selected the most robust combination with ms172 [reverse; R] and ms217 [R] to constitute the double-locus sequence typing (DLST) scheme for P. aeruginosa. This combination gave: (i) a complete genotype for 276/282 isolates (typability of 98%), (ii) 86 different types, and (iii) an ID of 0.968. Analysis of multiple isolates from the same patients or taps showed that DLST genotypes are generally stable over a period of several months. The high typability, discriminatory power, and ease of use of the proposed DLST scheme makes it a method of choice for local epidemiological analyses of P. aeruginosa. Moreover, the possibility to give unambiguous definition of types allowed to develop an Internet database ( http://www.dlst.org ) accessible by all. PMID:24326699

  2. 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.

  3. Review of pathogenesis and diagnostic methods of immediate relevance for epidemiology and control of Salmonella Dublin in cattle.

    PubMed

    Nielsen, Liza Rosenbaum

    2013-02-22

    Salmonella enterica subsp. enterica serovar Dublin (S. Dublin) receives increasing attention in cattle production. It is host-adapted to cattle, and leads to unacceptable levels of morbidity, mortality and production losses in both newly and persistently infected herds. Cattle health promoting institutions in several countries are currently constructing active surveillance programmes or voluntary certification programmes, and encourage control and eradication of S. Dublin infected cattle herds. There is a need to understand the underlying pathogenesis of the infection at both animal and herd level to design successful programmes. Furthermore, knowledge about and access to diagnostic tests for use in practice including information about test accuracy and interpretation of available diagnostic test methods are requested. The aim is to synthesise the abundant literature on elements of pathogenesis and diagnosis of immediate relevance for epidemiology and control of S. Dublin at animal and herd level. Relatively few in vivo studies on S. Dublin pathogenesis in cattle included more than a few animals and often showed varying result. It makes it difficult to draw conclusions about mechanisms that affect dissemination in cattle and that might be targets for control methods directed towards improving resistance against the bacteria, e.g. new vaccines. It is recommended to perform larger studies to elucidate dose-response relationships and age- and genetic effects of immunity. Furthermore, it is recommended to attempt to develop faster and more sensitive methods for detection of S. Dublin for diagnosis of infectious animals.

  4. 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...

  5. A data-driven epidemiological prediction method for dengue outbreaks using local and remote sensing data

    PubMed Central

    2012-01-01

    Background Dengue is the most common arboviral disease of humans, with more than one third of the world’s population at risk. Accurate prediction of dengue outbreaks may lead to public health interventions that mitigate the effect of the disease. Predicting infectious disease outbreaks is a challenging task; truly predictive methods are still in their infancy. Methods We describe a novel prediction method utilizing Fuzzy Association Rule Mining to extract relationships between clinical, meteorological, climatic, and socio-political data from Peru. These relationships are in the form of rules. The best set of rules is automatically chosen and forms a classifier. That classifier is then used to predict future dengue incidence as either HIGH (outbreak) or LOW (no outbreak), where these values are defined as being above and below the mean previous dengue incidence plus two standard deviations, respectively. Results Our automated method built three different fuzzy association rule models. Using the first two weekly models, we predicted dengue incidence three and four weeks in advance, respectively. The third prediction encompassed a four-week period, specifically four to seven weeks from time of prediction. Using previously unused test data for the period 4–7 weeks from time of prediction yielded a positive predictive value of 0.686, a negative predictive value of 0.976, a sensitivity of 0.615, and a specificity of 0.982. Conclusions We have developed a novel approach for dengue outbreak prediction. The method is general, could be extended for use in any geographical region, and has the potential to be extended to other environmentally influenced infections. The variables used in our method are widely available for most, if not all countries, enhancing the generalizability of our method. PMID:23126401

  6. 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 ...

  7. A survival tree method for the analysis of discrete event times in clinical and epidemiological studies.

    PubMed

    Schmid, Matthias; Küchenhoff, Helmut; Hoerauf, Achim; Tutz, Gerhard

    2016-02-28

    Survival trees are a popular alternative to parametric survival modeling when there are interactions between the predictor variables or when the aim is to stratify patients into prognostic subgroups. A limitation of classical survival tree methodology is that most algorithms for tree construction are designed for continuous outcome variables. Hence, classical methods might not be appropriate if failure time data are measured on a discrete time scale (as is often the case in longitudinal studies where data are collected, e.g., quarterly or yearly). To address this issue, we develop a method for discrete survival tree construction. The proposed technique is based on the result that the likelihood of a discrete survival model is equivalent to the likelihood of a regression model for binary outcome data. Hence, we modify tree construction methods for binary outcomes such that they result in optimized partitions for the estimation of discrete hazard functions. By applying the proposed method to data from a randomized trial in patients with filarial lymphedema, we demonstrate how discrete survival trees can be used to identify clinically relevant patient groups with similar survival behavior.

  8. A survival tree method for the analysis of discrete event times in clinical and epidemiological studies.

    PubMed

    Schmid, Matthias; Küchenhoff, Helmut; Hoerauf, Achim; Tutz, Gerhard

    2016-02-28

    Survival trees are a popular alternative to parametric survival modeling when there are interactions between the predictor variables or when the aim is to stratify patients into prognostic subgroups. A limitation of classical survival tree methodology is that most algorithms for tree construction are designed for continuous outcome variables. Hence, classical methods might not be appropriate if failure time data are measured on a discrete time scale (as is often the case in longitudinal studies where data are collected, e.g., quarterly or yearly). To address this issue, we develop a method for discrete survival tree construction. The proposed technique is based on the result that the likelihood of a discrete survival model is equivalent to the likelihood of a regression model for binary outcome data. Hence, we modify tree construction methods for binary outcomes such that they result in optimized partitions for the estimation of discrete hazard functions. By applying the proposed method to data from a randomized trial in patients with filarial lymphedema, we demonstrate how discrete survival trees can be used to identify clinically relevant patient groups with similar survival behavior. PMID:26358826

  9. 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

  10. 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.

  11. Statistical methods in epidemiology: Karl Pearson, Ronald Ross, Major Greenwood and Austin Bradford Hill, 1900-1945.

    PubMed

    Hardy, Anne; Magnello, M Eileen

    2002-01-01

    The tradition of epidemiological study through observation and the use of vital statistics dates back to the 18th century in Britain. At the close of the 19th century, however, a new and more sophisticated statistical approach emerged, from a base in the discipline of mathematics, which was eventually to transform the practice of epidemiology. This paper traces the evolution of that new analytical approach within English epidemiology through the work of four key contributors to its inception and establishment within the wider discipline. PMID:12134737

  12. Epidemiology of Candida infection. II. Application of biochemical methods for typing of Candida albicans strains.

    PubMed

    Budak, A

    1990-01-01

    Biochemical profiles of 350 C. albicans isolates from five towns in Poland and from Freiburg in Germany were determined on the basis of nine biochemical tests of Odds and Abbott method. API 20 C AUX system and additionally a resistogram. The analysis of the strains according to Odds' and Abbotts's system showed that investigated strains can be typed into 9 profile codes of common biochemical patterns. There were some differences among the profiles according to their geographical origin and anatomical sources of the isolation. On the basis of the ability C. albicans strains to assimilate of carbon sources, 350 isolates were categorised into 13 separate auxotrophic profiles with the major one: 2,576,174 accounting for 81% of the total. The majority of the investigated isolates were susceptible to antifungal agents (83%). A disproportionate distribution of auxotrophic profiles limited the use of resistogram method and API 20 C AUX as systems for typing C. albicans strains. On the other hand, the method of Odds and Abbott provides valuable criteria for typing of C. albicans. PMID:2130802

  13. Evidence-based planning and costing palliative care services for children: novel multi-method epidemiological and economic exemplar

    PubMed Central

    2013-01-01

    Background Children’s palliative care is a relatively new clinical specialty. Its nature is multi-dimensional and its delivery necessarily multi-professional. Numerous diverse public and not-for-profit organisations typically provide services and support. Because services are not centrally coordinated, they are provided in a manner that is inconsistent and incoherent. Since the first children’s hospice opened in 1982, the epidemiology of life-limiting conditions has changed with more children living longer, and many requiring transfer to adult services. Very little is known about the number of children living within any given geographical locality, costs of care, or experiences of children with ongoing palliative care needs and their families. We integrated evidence, and undertook and used novel methodological epidemiological work to develop the first evidence-based and costed commissioning exemplar. Methods Multi-method epidemiological and economic exemplar from a health and not-for-profit organisation perspective, to estimate numbers of children under 19 years with life-limiting conditions, cost current services, determine child/parent care preferences, and cost choice of end-of-life care at home. Results The exemplar locality (North Wales) had important gaps in service provision and the clinical network. The estimated annual total cost of current children’s palliative care was about £5.5 million; average annual care cost per child was £22,771 using 2007 prevalence estimates and £2,437- £11,045 using new 2012/13 population-based prevalence estimates. Using population-based prevalence, we estimate 2271 children with a life-limiting condition in the general exemplar population and around 501 children per year with ongoing palliative care needs in contact with hospital services. Around 24 children with a wide range of life-limiting conditions require end-of-life care per year. Choice of end-of-life care at home was requested, which is not currently

  14. 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

  15. Epidemiology and changed surgical treatment methods for fractures of the distal radius

    PubMed Central

    2013-01-01

    Background and purpose The incidence of fractures of the distal radius may have changed over the last decade, and operative treatment has been commoner during that time. We investigated the incidence of fractures of the distal radius and changing trends in surgical treatment during the period 2004–2010. Patients and methods Registry data on 42,583 patients with a fracture of the distal radius from 2004 to 2010 were evaluated regarding diagnosis, age, sex, and surgical treatment. Results The crude incidence rate was 31 per 104 person-years with a bimodal distribution. After the age of 45 years, the incidence rate in women increased rapidly and leveled off first at a very high age. The incidence rate in postmenopausal women was lower than previously reported. In men, the incidence was low and it increased slowly until the age of 80 years, when it amounted to 31 per 104 person-years. The number of surgical procedures increased by more than 40% despite the fact that there was reduced incidence during the study period. In patients ≥ 18 years of age, the proportion of fractures treated with plating increased from 16% to 70% while the use of external fixation decreased by about the same amount. Interpretation The incidence rate of distal radius fractures in postmenopausal women appears to have decreased over the last few decades. There has been a shift in surgical treatment from external fixation to open reduction and plating. PMID:23594225

  16. Two method measurement for adolescent obesity epidemiology: Reducing the bias in self report of height and weight

    PubMed Central

    Drake, Keith M.; Longacre, Meghan R.; Dalton, Madeline A.; Langeloh, Gail; Peterson, Karen E.; Titus, Linda J.; Beach, Michael L.

    2013-01-01

    Background Despite validation studies demonstrating substantial bias, epidemiologic studies typically use self-reported height and weight as primary measures of body mass index due to feasibility and resource limitations. Purpose To demonstrate a method for calculating accurate and precise estimates that use body mass index when objectively measuring height and weight in a full sample is not feasible. Methods As part of a longitudinal study of adolescent health, 1,840 adolescents (aged 12–18) self-reported their height and weight during telephone surveys. Height and weight was measured for 407 of these adolescents. Sex specific, age-adjusted obesity status was calculated from self-reported and from measured height and weight. Prevalence and predictors of obesity were estimated using 1) self-reported data, 2) measured data, and 3) multiple imputation (of measured data). Results Among adolescents with self-reported and measured data, the obesity prevalence was lower when using self-report compared to actual measurements (p < 0.001). The obesity prevalence from multiple imputation (20%) was much closer to estimates based solely on measured data (20%) compared to estimates based solely on self-reported data (12%), indicating improved accuracy. In multivariate models, estimates of predictors of obesity were more accurate and approximately as precise (similar confidence intervals) as estimates based solely on self-reported data. Conclusions The two-method measurement design offers researchers a technique to reduce the bias typically inherent in self-reported height and weight without needing to collect measurements on the full sample. This technique enhances the ability to detect real, statistically significant differences, while minimizing the need for additional resources. PMID:23684216

  17. 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

  18. [Opportunity and challenge on molecular epidemiology].

    PubMed

    Duan, G C; Chen, S Y

    2016-08-10

    Molecular epidemiology, a branch of epidemiology, combines the theories and methods, both in epidemiology and molecular biology. Molecular epidemiology mainly focuses on biological markers, describing the distribution, occurrence, development and prognosis of diseases at the molecular level. The completion of Human Genome Project and rapid development of Precision Medicine and Big Data not only offer the new development opportunities but also bring about a higher demand and new challenge for molecular epidemiology. PMID:27539332

  19. 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

  20. 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.

  1. Traditional epidemiology, modern epidemiology, and public health.

    PubMed Central

    Pearce, N

    1996-01-01

    There have been significant developments in epidemiologic methodology during the past century, including changes in basic concepts, methods of data analysis, and methods of exposure measurement. However, the rise of modern epidemiology has been a mixed blessing, and the new paradigm has major shortcomings, both in public health and in scientific terms. The changes in the paradigm have not been neutral but have rather helped change--and have reflected changes in--the way in which epidemiologists think about health and disease. The key issue has been the shift in the level of analysis from the population to the individual. Epidemiology has largely ceased to function as part of a multidisciplinary approach to understanding the causation of disease in populations and has become a set of generic methods for measuring associations of exposure and disease in individuals. This reductionist approach focuses on the individual, blames the victim, and produces interventions that can be harmful. We seem to be using more and more advanced technology to study more and more trivial issues, while the major causes of disease are ignored. Epidemiology must reintegrate itself into public health and must rediscover the population perspective. PMID:8629719

  2. 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.

  3. Competency in health care management: a training model in epidemiologic methods for assessing and improving the quality of clinical practice through evidence-based decision making.

    PubMed

    Hudak, R P; Jacoby, I; Meyer, G S; Potter, A L; Hooper, T I; Krakauer, H

    1997-01-01

    This article describes a training model that focuses on health care management by applying epidemiologic methods to assess and improve the quality of clinical practice. The model's uniqueness is its focus on integrating clinical evidence-based decision making with fundamental principles of resource management to achieve attainable, cost-effective, high-quality health outcomes. The target students are current and prospective clinical and administrative executives who must optimize decision making at the clinical and managerial levels of health care organizations.

  4. 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…

  5. 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

  6. Polygenic Epidemiology.

    PubMed

    Dudbridge, Frank

    2016-05-01

    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

  7. Cognitive epidemiology

    PubMed Central

    Deary, Ian J; Batty, G David

    2007-01-01

    This glossary provides a guide to some concepts, findings and issues of discussion in the new field of research in which intelligence test scores are associated with mortality and morbidity. Intelligence tests are devised and studied by differential psychologists. Some of the major concepts in differential psychology are explained, especially those regarding cognitive ability testing. Some aspects of IQ (intelligence) tests are described and some of the major tests are outlined. A short guide is given to the main statistical techniques used by differential psychologists in the study of human mental abilities. There is a discussion of common epidemiological concepts in the context of cognitive epidemiology. PMID:17435201

  8. Cultural epidemiology of pandemic influenza in urban and rural Pune, India: a cross-sectional, mixed-methods study

    PubMed Central

    Sundaram, Neisha; Schaetti, Christian; Purohit, Vidula; Kudale, Abhay; Weiss, Mitchell G

    2014-01-01

    Objective To identify and compare sociocultural features of pandemic influenza with reference to illness-related experience, meaning and behaviour in urban and rural areas of India. Design Cross-sectional, mixed-methods, cultural epidemiological survey with vignette-based interviews. Semistructured explanatory model interviews were used to study community ideas of the 2009 influenza pandemic. In-depth interviews elaborated respondents’ experience during the pandemic. Setting Urban and rural communities, Pune district, western India. Participants Survey of urban (n=215) and rural (n=221) residents aged between 18 and 65 years. In-depth interviews of respondents with a history of 2009 pandemic influenza (n=6). Results More urban (36.7%) than rural respondents (16.3%, p<0.001) identified the illness in the vignette as ‘swine flu’. Over half (56.7%) believed the illness would be fatal without treatment, but with treatment 96% predicted full recovery. Worry (‘tension’) about the illness was reported as more troubling than somatic symptoms. The most common perceived causes—‘exposure to a dirty environment’ and ‘cough or sneeze of an infected person’–were more prominent in the urban group. Among rural respondents, climatic conditions, drinking contaminated water, tension and cultural ideas on humoral imbalance from heat-producing or cold-producing foods were more prominent. The most widely reported home treatment was herbal remedies; more rural respondents suggested reliance on prayer, and symptom relief was more of a priority for urban respondents. Government health services were preferred in the urban communities, and rural residents relied more than urban residents on private facilities. The important preventive measures emphasised were cleanliness, wholesome lifestyle and vaccines, and more urban respondents reported the use of masks. In-depth interviews indicated treatment delays during the 2009 pandemic, especially among rural patients

  9. Is there epidemiology in Russia?

    PubMed Central

    Vlassov, V.

    2000-01-01

    OBJECTIVE—To examine the current state of epidemiology in Russia.
DESIGN—The structure of clinical research and statistical methods was used to shed light on the epidemiology in Russia. The frequencies of specific study designs were evaluated using Medline data for 1970-1997. To determine the proportion of advanced design clinical studies the frequency of cohort, prospective, follow up, or longitudinal studies, and controlled trials was evaluated. All diagnosis related studies were found to determine the usage of advanced statistical technique (ROC analysis). The adequacy of Medline information was checked by hand search of journals. All dissertations in epidemiology defended in Russia in 1995 and 1996 were evaluated for their methodology. The curriculum recommended by Ministry of Health to Medical Universities was evaluated. Available literature and library indexing of epidemiological terms examined.
MAIN RESULTS—Russian medical research uses less frequently advanced study designs and methods of data analysis. Medical students are taught epidemiology as a science of spread of infectious diseases. There is no department of epidemiology in Russian universities where epidemiology is taught in the modern sense and no epidemiological and biostatistical periodicals available in Russia.
CONCLUSION—Epidemiology in Russia remains in an archaic state of science of the spread of infectious diseases and it is detrimental to methodology of medical research in Russia.


Keywords: Soviet Union; Russia; study design; comparative studies PMID:10990475

  10. Nutritional Epidemiology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although observations on relationships between diet and health have always been recognized—the systematic science of nutritional epidemiology in populations is relatively recent. Important observations propelling the field of nutrition forward were numerous in the 18th and 19th centuries, as it was...

  11. Causality in epidemiology.

    PubMed

    Kamangar, Farin

    2012-10-01

    This article provides an introduction to the meaning of causality in epidemiology and methods that epidemiologists use to distinguish causal associations from non-causal ones. Alternatives to causal association are discussed in detail. Hill's guidelines, set forth approximately 50 years ago, and more recent developments are reviewed. The role of religious and philosophic views in our understanding of causality is briefly discussed.

  12. 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

  13. Epidemiological investigation of a Legionnaires' disease outbreak in Christchurch, New Zealand: the value of spatial methods for practical public health.

    PubMed

    White, P S; Graham, F F; Harte, D J G; Baker, M G; Ambrose, C D; Humphrey, A R G

    2013-04-01

    Between April and August 2005 Christchurch, New Zealand experienced an outbreak of Legionnaires' disease. There were 19 laboratory-confirmed case including three deaths. Legionella pneumophila serogroup 1 (Lpsg1) was identified as the causative agent for all cases. A case-control study indicated a geographical association between the cases but no specific common exposures. Rapid spatial epidemiological investigation confirmed the association and identified seven spatially significant case clusters. The clusters were all sourced in the same area and exhibited a clear anisotropic process (noticeable direction) revealing a plume effect consistent with aerosol dispersion from a prevailing southwesterly wind. Four out of five cases tested had indistinguishable allele profiles that also matched environmental isolates from a water cooling tower within the centre of the clusters. This tower was considered the most probable source for these clusters. The conclusion would suggest a maximum dispersal distance in this outbreak of 11·6 km. This work illustrated the value of geostatistical techniques for infectious disease epidemiology and for providing timely information during outbreak investigations. PMID:22697112

  14. Molecular Epidemiology of Malaria

    PubMed Central

    Conway, David J.

    2007-01-01

    Malaria persists as an undiminished global problem, but the resources available to address it have increased. Many tools for understanding its biology and epidemiology are well developed, with a particular richness of comparative genome sequences. Targeted genetic manipulation is now effectively combined with in vitro culture assays on the most important human parasite, Plasmodium falciparum, and with in vivo analysis of rodent and monkey malaria parasites in their laboratory hosts. Studies of the epidemiology, prevention, and treatment of human malaria have already been influenced by the availability of molecular methods, and analyses of parasite polymorphisms have long had useful and highly informative applications. However, the molecular epidemiology of malaria is currently undergoing its most substantial revolution as a result of the genomic information and technologies that are available in well-resourced centers. It is a challenge for research agendas to face the real needs presented by a disease that largely exists in extremely resource-poor settings, but it is one that there appears to be an increased willingness to undertake. To this end, developments in the molecular epidemiology of malaria are reviewed here, emphasizing aspects that may be current and future priorities. PMID:17223628

  15. 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.

  16. 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

  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. Applying standard epidemiological methods for investigating foodborne disease outbreak in resource-poor settings: lessons from Vietnam.

    PubMed

    Vo, Thuan Huu; Nguyen, Dat Van; Le, Loan Thi Kim; Phan, Lan Trong; Nuorti, J Pekka; Tran Minh, Nguyen Nhu

    2014-07-01

    An outbreak of gastroenteritis occurred among workers of company X after eating lunch prepared by a catering service. Of 430 workers attending the meal, 56 were hospitalized with abdominal pain, diarrhea, vomiting, and nausea, according to the initial report. We conducted an investigation to identify the extent, vehicle, and source of the outbreak. In our case-control study, a case was a worker who attended the meal and who was hospitalized with acute gastroenteritis; controls were randomly selected from non-ill workers. Cases and controls were interviewed using a standard questionnaire. We used logistic regression to calculate adjusted odds ratios for the consumption of food items. Catering service facilities and food handlers working for the service were inspected. Food samples from the catering service were tested at reference laboratories. Of hospitalized cases, 54 fulfilled the case definition, but no stool specimens were collected for laboratory testing. Of four food items served during lunch, only "squash and pork soup" was significantly associated with gastroenteritis, with an adjusted odds ratio of 9.5 (95 % CI 3.2, 27.7). The caterer did not separate cooked from raw foods but used the same counter for both. Cooked foods were kept at room temperature for about 4 h before serving. Four of 14 food handlers were not trained on basic food safety principles and did not have health certificates. Although no microbiological confirmation was obtained, our epidemiological investigation suggested that squash and pork soup caused the outbreak. Hospitals should be instructed to obtain stool specimens from patients with gastroenteritis. Food catering services should be educated in basic food safety measures.

  19. 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

  20. 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. PMID:27637958

  1. Sewage-based epidemiology in monitoring the use of new psychoactive substances: Validation and application of an analytical method using LC-MS/MS.

    PubMed

    Kinyua, Juliet; Covaci, Adrian; Maho, Walid; McCall, Ann-Kathrin; Neels, Hugo; van Nuijs, Alexander L N

    2015-09-01

    Sewage-based epidemiology (SBE) employs the analysis of sewage to detect and quantify drug use within a community. While SBE has been applied repeatedly for the estimation of classical illicit drugs, only few studies investigated new psychoactive substances (NPS). These compounds mimic effects of illicit drugs by introducing slight modifications to chemical structures of controlled illicit drugs. We describe the optimization, validation, and application of an analytical method using liquid chromatography coupled to positive electrospray tandem mass spectrometry (LC-ESI-MS/MS) for the determination of seven NPS in sewage: methoxetamine (MXE), butylone, ethylone, methylone, methiopropamine (MPA), 4-methoxymethamphetamine (PMMA), and 4-methoxyamphetamine (PMA). Sample preparation was performed using solid-phase extraction (SPE) with Oasis MCX cartridges. The LC separation was done with a HILIC (150 x 3 mm, 5 µm) column which ensured good resolution of the analytes with a total run time of 19 min. The lower limit of quantification (LLOQ) was between 0.5 and 5 ng/L for all compounds. The method was validated by evaluating the following parameters: sensitivity, selectivity, linearity, accuracy, precision, recoveries and matrix effects. The method was applied on sewage samples collected from sewage treatment plants in Belgium and Switzerland in which all investigated compounds were detected, except MPA and PMA. Furthermore, a consistent presence of MXE has been observed in most of the sewage samples at levels higher than LLOQ.

  2. Interpreting epidemiological research: blinded comparison of methods used to estimate the prevalence of inherited mutations in BRCA1

    PubMed Central

    Eng, C.; Brody, L.; Wagner, T.; Devilee, P.; Vijg, J.; Szabo, C.; Tavtigian, S.; Nathanson, K.; Ostrander, E.; Frank, T.

    2001-01-01

    While sequence analysis is considered by many to be the most sensitive method of detecting unknown mutations in large genes such as BRCA1, most published estimates of the prevalence of mutations in this gene have been derived from studies that have used other methods of gene analysis. In order to determine the relative sensitivity of techniques that are widely used in research on BRCA1, a set of blinded samples containing 58 distinct mutations were analysed by four separate laboratories. Each used one of the following methods: single strand conformational polymorphism analysis (SSCP), conformation sensitive gel electrophoresis (CSGE), two dimensional gene scanning (TDGS), and denaturing high performance liquid chromatography (DHPLC). Only the laboratory using DHPLC correctly identified each of the mutations. The laboratory using TDGS correctly identified 91% of the mutations but produced three apparent false positive results. The laboratories using SSCP and CSGE detected abnormal migration for 72% and 76% of the mutations, respectively, but subsequently confirmed and reported only 65% and 60% of mutations, respectively. False negatives therefore resulted not only from failure of the techniques to distinguish wild type from mutant, but also from failure to confirm the mutation by sequence analysis as well as from human errors leading to misreporting of results. These findings characterise sources of error in commonly used methods of mutation detection that should be addressed by laboratories using these methods. Based upon sources of error identified in this comparison, it is likely that mutations in BRCA1 and BRCA2 are more prevalent than some studies have previously reported. The findings of this comparison provide a basis for interpreting studies of mutations in susceptibility genes across many inherited cancer syndromes.


Keywords: BRCA1; mutation detection; cancer genetics PMID:11748305

  3. Genetics and epidemiology, congenital anomalies and cancer

    SciTech Connect

    Friedman, J.M.

    1997-03-01

    Many of the basic statistical methods used in epidemiology - regression, analysis of variance, and estimation of relative risk, for example - originally were developed for the genetic analysis of biometric data. The familiarity that many geneticists have with this methodology has helped geneticists to understand and accept genetic epidemiology as a scientific discipline. It worth noting, however, that most of the work in genetic epidemiology during the past decade has been devoted to linkage and other family studies, rather than to population-based investigations of the type that characterize much of mainstream epidemiology. 30 refs., 2 tabs.

  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. 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.

  6. 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

  7. 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…

  8. 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.

  9. 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.

  10. 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

  11. 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. PMID:27175693

  12. 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.

  13. Application of the Random Forest method to analyse epidemiological and phenotypic characteristics of Salmonella 4,[5],12:i:- and Salmonella Typhimurium strains.

    PubMed

    Barco, L; Mancin, M; Ruffa, M; Saccardin, C; Minorello, C; Zavagnin, P; Lettini, A A; Olsen, J E; Ricci, A

    2012-11-01

    Salmonella enterica 4,[5],12:i:- is a monophasic variant of S. Typhimurium. In the last decade, its prevalence rose sharply. Although S. 4,[5],12:i:- and S. Typhimurium are known to pose a considerable public health risk, there is no detailed information on the circulation of these serovars in Italy, particularly as far as veterinary isolates are concerned. For this reason, a data set of 877 strains isolated in the north-east of Italy from foodstuffs, animals and environment was analysed during 2005-2010. The Random Forests (RF) method was used to identify the most important epidemiological and phenotypic variables to show the difference between the two serovars. Both descriptive analysis and RF revealed that S. 4,[5],12:i:- is less heterogeneous than S. Typhimurium. RF highlighted that phage type was the most important variable to differentiate the two serovars. The most common phage types identified for S. 4,[5],12:i:- were DT20a, U311 and DT193. The same phage types were also found in S. Typhimurium isolates, although with a much lower prevalence. DT7 and DT120 were ascribed to the two serovars at comparable levels. DT104, DT2 and DT99 were ascribed exclusively to S. Typhimurium, and almost all the other phage types identified were more related to the latter serovar. Such data confirm that phage typing can provide an indication of the biphasic or monophasic state of the strains investigated and could therefore support serotyping results. However, phage typing cannot be used as the definitive method to differentiate the two serovars, as part of the phage types were detected for both serovars and, in particular, all phage types found for S. 4,[5],12:i- were found also for S. Typhimurium.

  14. [The specific epidemiological surveillance of dengue: the method and its importance since the dengue-2 epidemic in French Polynesia in 1996].

    PubMed

    Deparis, X; Chungue, E; Pauck, S; Roche, C; Murgue, B; Gleize, L

    1998-07-01

    Dengue fever is present in tropical and subtropical regions and its geographical extension and the simultaneous increase of its mortality are worrisome. In endemic or epidemic countries, the aim of dengue-specific epidemiological surveillance is to confirm as soon as possible the circulation of a new viral dengue serotype, i.e. the beginning of an epidemic. The efficiency of the control strategy is improved by an earlier epidemic alert. In French Polynesia, dengue-3 virus circulated since 1989 at low level and, in May 1996, a specific epidemiological surveillance was undertaken because of the threat of a dengue-4 epidemic. From each suspected dengue case reported by 18 Polynesian physicians located in the Société Islands, a blood sample was taken for virological assay and clinical data were reported. Between May and November 1996, the virology unit of the Institut Malardé isolated 21 viruses (2 dengue-3 and 19 dengue-2) from 302 suspected cases. The dengue-specific epidemiological surveillance confirmed that dengue-2 virus was circulating and reduced the time of the epidemiological alert by 2 or 3 months compared to previous epidemics. Taking into account the day of illness, a logistic regression undertaken on the clinical data showed that the absence of cough was the only predictive sign of dengue diagnosis. The performance of this dengue-specific epidemiological surveillance system led us to consider its implementation in all concerned countries. A collaboration with international reference laboratories could be a solution for the developing countries.

  15. Ecogeographic Genetic Epidemiology

    PubMed Central

    Sloan, Chantel D.; Duell, Eric J.; Shi, Xun; Irwin, Rebecca; Andrew, Angeline S.; Williams, Scott M.; Moore, Jason H.

    2009-01-01

    Complex diseases such as cancer and heart disease result from interactions between an individual's genetics and environment, i.e. their human ecology. Rates of complex diseases have consistently demonstrated geographic patterns of incidence, or spatial “clusters” of increased incidence relative to the general population. Likewise, genetic subpopulations and environmental influences are not evenly distributed across space. Merging appropriate methods from genetic epidemiology, ecology and geography will provide a more complete understanding of the spatial interactions between genetics and environment that result in spatial patterning of disease rates. Geographic Information Systems (GIS), which are tools designed specifically for dealing with geographic data and performing spatial analyses to determine their relationship, are key to this kind of data integration. Here the authors introduce a new interdisciplinary paradigm, ecogeographic genetic epidemiology, which uses GIS and spatial statistical analyses to layer genetic subpopulation and environmental data with disease rates and thereby discern the complex gene-environment interactions which result in spatial patterns of incidence. PMID:19025788

  16. 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…

  17. 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.

  18. [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. PMID:26155657

  19. [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.

  20. 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

  1. Epidemiology, Molecular Epidemiology and Evolution of Bovine Respiratory Syncytial Virus

    PubMed Central

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

    2012-01-01

    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. PMID:23202546

  2. [Epidemiology of Kawasaki disease].

    PubMed

    Nakamura, Yosikazu

    2014-09-01

    Epidemiologic features of Kawasaki disease, in particular in Japan, were summarized. There were three aspects of the epidemiology: (1) frequency(descriptive epidemiology), (2) risk factors(e.g. case-control studies), and (3) natural history(follow-up studies). The nationwide surveys, which was established in 1970, revealed the epidemiologic features of the disease. The number of patients and incidence rate have elevated since mid-1990s. Descriptive features indicates the association between disease onset and both infection and the hosts' factors. A follow-up study over 20 years has been conducted, but it should be continued till all the participants pass away.

  3. [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. PMID:9504120

  4. 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. PMID:26282428

  5. 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

  6. 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

  7. 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

  8. 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

  9. The future of epidemiology.

    PubMed

    Ness, Roberta B; Andrews, Elizabeth B; Gaudino, James A; Newman, Anne B; Soskolne, Colin L; Stürmer, Til; Wartenberg, Daniel E; Weiss, Stanley H

    2009-11-01

    In this article, the authors discuss current challenges and opportunities in epidemiology that will affect the field's future. Epidemiology is commonly considered the methodologic backbone for the fields of public health and outcomes research because its practitioners describe patterns of disease occurrence, identify risk factors and etiologic determinants, and demonstrate the usefulness of interventions. Like most aspects of science, epidemiology is in rapid flux. Several factors that are influencing and will continue to influence epidemiology and the health of the public include factors fundamental to framing the discipline of epidemiology (i.e., its means of communication, its methodologies, its access to data, its values, its population perspective), factors relating to scientific advances (e.g., genomics, comparative effectiveness in therapeutics), and factors shaping human health (e.g., increasing globalism, the environment, disease and lifestyle, demographics, infectious disease). PMID:19858828

  10. Vaccine epidemiology: A review.

    PubMed

    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

  11. 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

  12. [Epidemiological research in Brazil].

    PubMed

    Guimarães, R; Lourenço-De-Oliveira, R; Cosac, S

    2001-08-01

    The current epidemiological research in Brazil is described. Secondary data sources were consulted, such as the year 2000 database of the Brazilian Directory of Research Groups and the National Board of Scientific and Technological Development (CNPq). The criterion to identify a group as a research one relies on the existence of at least one research line in the field of epidemiology, as defined by the group leader. After identifying the defined universe of epidemiological research, which included 176 groups and 320 different research lines, the following issues were presented and discussed: the relationships between research financing and health research, focusing on CAPES (Coordination Center for the Advance of University Professionals) graduation programs, public health research and epidemiological research, geographic and institutional distribution and outreach of the current epidemiological research, the researchers and students directly participating in epidemiological research, research topics and patterns of disseminating research findings; the journals where papers in its fullness were published; the financial support of the epidemiological research focusing on the 23 officially recognized graduate programs in public health field. PMID:11600921

  13. Networks and the Epidemiology of Infectious Disease

    PubMed Central

    Danon, Leon; Ford, Ashley P.; House, Thomas; Jewell, Chris P.; Keeling, Matt J.; Roberts, Gareth O.; Ross, Joshua V.; Vernon, Matthew C.

    2011-01-01

    The science of networks has revolutionised research into the dynamics of interacting elements. It could be argued that epidemiology in particular has embraced the potential of network theory more than any other discipline. Here we review the growing body of research concerning the spread of infectious diseases on networks, focusing on the interplay between network theory and epidemiology. The review is split into four main sections, which examine: the types of network relevant to epidemiology; the multitude of ways these networks can be characterised; the statistical methods that can be applied to infer the epidemiological parameters on a realised network; and finally simulation and analytical methods to determine epidemic dynamics on a given network. Given the breadth of areas covered and the ever-expanding number of publications, a comprehensive review of all work is impossible. Instead, we provide a personalised overview into the areas of network epidemiology that have seen the greatest progress in recent years or have the greatest potential to provide novel insights. As such, considerable importance is placed on analytical approaches and statistical methods which are both rapidly expanding fields. Throughout this review we restrict our attention to epidemiological issues. PMID:21437001

  14. Epidemiology of Crohn's Disease.

    PubMed

    Sandler, R S; Golden, A L

    1986-04-01

    Although our current understanding is limited, epidemiologic investigation of Crohn's disease holds great promise. Certain aspects of the epidemiology are clear. The incidence of Crohn's disease, which has increased over the past few decades, may have reached a plateau. The disease has its peak onset in early life, with a second peak among the elderly. It is more common in the developed countries and among Jews. Whether the disease is related to occupation, social class, marital status, stress, infection, diet, smoking, and oral contraceptives is less certain. This paper reviews the epidemiology of Crohn's disease and proposes areas in which further research is needed.

  15. Evolution and social epidemiology.

    PubMed

    Nishi, Akihiro

    2015-11-01

    Evolutionary biology, which aims to explain the dynamic process of shaping the diversity of life, has not yet significantly affected thinking in social epidemiology. Current challenges in social epidemiology include understanding how social exposures can affect our biology, explaining the dynamics of society and health, and designing better interventions that are mindful of the impact of exposures during critical periods. I review how evolutionary concepts and tools, such as fitness gradient in cultural evolution, evolutionary game theory, and contemporary evolution in cancer, can provide helpful insights regarding social epidemiology.

  16. "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.

  17. Epidemiology of Substance Use Disorders

    PubMed Central

    Merikangas, Kathleen R.; McClair, Vetisha L.

    2013-01-01

    Epidemiological studies of substance use and substance use disorders (SUDs) have provided an abundance of data on the patterns of substance use in nationally representative samples across the world (Degenhardt et al. 2008; Johnston et al. 2011; SAMHSA 2011). This paper presents a summary of the goals, methods and recent findings on the epidemiology of substance use and disorders in the general population of adults and adolescents and describes the methods and findings on the genetic epidemiology of drug use disorders. The high 12 month prevalence rates of substance dependence in U.S. adults (about 12% for alcohol and 2–3% for illicit drugs) approximate those of other mental disorders as well as chronic physical disorders with major public health impact. New findings from the nationally representative samples of U.S. youth reveal that the lifetime prevalence of alcohol use disorders is approximately 8% and illicit drug use disorders is 2–3% (Merikangas et al. 2010; Swendsen et al. in press, SAMSHA, 2011). The striking increase in prevalence rates from ages 13 to 18 highlight adolescence as the key period of development of substance use disorders. The application of genetic epidemiological studies has consistently demonstrated that genetic factors have a major influence on progression of substance use to dependence, whereas environmental factors unique to the individual play an important role in exposure and initial use of substances. Identification of specific susceptibility genes and environmental factors that influence exposure and progression of drug use may enhance our ability to prevent and treat substance use disorders. PMID:22543841

  18. Epidemiology of Enterocytozoon bieneusi Infection in Humans.

    PubMed

    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.

  19. 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

  20. 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...

  1. Epidemiology of varicocele

    PubMed Central

    Alsaikhan, Bader; Alrabeeah, Khalid; Delouya, Guila; Zini, Armand

    2016-01-01

    Varicocele is a common problem in reproductive medicine practice. A varicocele is identified in 15% of healthy men and up to 35% of men with primary infertility. The exact pathophysiology of varicoceles is not very well understood, especially regarding its effect on male infertility. We have conducted a systematic review of studies evaluating the epidemiology of varicocele in the general population and in men presenting with infertility. In this article, we have identified some of the factors that can influence the epidemiological aspects of varicoceles. We also recognize that varicocele epidemiology remains incompletely understood, and there is a need for well-designed, large-scale studies to fully define the epidemiological aspects of this condition. PMID:26763551

  2. 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.

  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. 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.

  5. 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

  6. [Molecular and genetic epidemiology].

    PubMed

    Kang, D H

    2001-04-21

    Molecular epidemiology is defined as "the use of biological markers in epidemiologic research" and genetic epidemiology is defined as "the study of the interaction between genetic and environmental factors in epidemiologic research". Traditional epidemiologic approaches defined as "the study of the distribution and determinants of disease frequency in human population" could not address the importance of genetic susceptibility of humans in disease occurrence. However, the use of biological or genetic markers identified and characterized by the help of advance in molecular biology and human genetics now can provide us better understanding of multi-factorial or multistep disease occurrence in humans. Biological markers used in molecular epidemiology are classified into three groups: biomarkers of exposure (i.e., carcinogen metabolites in human urine, DNA-adducts, etc.), biomarkers of effects (i.e., oncoproteins, tumor markers, etc.), and biomarkers of susceptibility (i.e., genetic polymorphisms of carcinogen metabolism enzymes, DNA repair, etc.). Susceptibility genes involved in disease pathogenesis are categorized into two groups: high penetrance genes (i.e., BRAC1, RB, etc.) and low penetrance genes (i.e., GSTs, XRCC1, etc.). This paper will address the usefulnesses of bomarkers in edpidemiologic research and will show the examples of the use of selected low penetrance genes involved in human carcinogenesis. The importance of multidisciplinary approaches among epidemiologists, molecular biologists, and human geneticists will also be discussed.

  7. 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

  8. 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

  9. 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

    1983-08-01

    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. PMID:6135832

  10. Shifting epidemiology of Flaviviridae.

    PubMed

    Petersen, Lyle R; Marfin, Anthony A

    2005-04-01

    The dengue, West Nile, Japanese encephalitis and yellow fever viruses are important mosquito-borne viruses whose epidemiology is shifting in response to changing societal factors, such as increasing commerce, urbanization of rural areas, and population growth. All four viruses are expanding geographically, as exemplified by the emergence of West Nile virus in the Americas and Japanese encephalitis virus in Australasia. The large, recent global outbreaks of severe neurological disease caused by West Nile virus, the increasing frequency of dengue hemorrhagic fever outbreaks in the Americas, and the emergence of yellow fever virus vaccination-associated viscerotropic disease, are new clinical epidemiologic trends. These worrisome epidemiologic trends will probably continue in coming decades, as a reversal of their societal and biological drivers is not in sight. Nevertheless, the substantial reductions in Japanese encephalitis virus incidence resulting from vaccination programs and economic development in some Asian countries provide some encouragement within this overall guarded outlook.

  11. Whose epidemiology, whose health?

    PubMed

    Wing, S

    1998-01-01

    Simplistic claims about the objectivity of science have been challenged from a variety of perspectives. Evaluation of the external context of production of knowledge and the methodological approaches to posing questions and assembling evidence shows that there is no pure "science"; rather, all scientific knowledge is shaped by the social history of its production. Examples are given of how quantitative concepts in modern epidemiology influence the recognition of the causes of disease. The author uses the phenomenon of intensive swine production by vertically integrated agribusiness to illustrate how broad problems such as environmental racism, agricultural determinants of nutrition, loss of natural resources, and conditions conducive to emergence of new diseases are hidden by epidemiological approaches that fit into corporate policy perspectives. It is critically important to ask who produces epidemiological knowledge, and whose health is promoted by that knowledge.

  12. Epidemiology of Lung Cancer.

    PubMed

    Mao, Yousheng; Yang, Ding; He, Jie; Krasna, Mark J

    2016-07-01

    Lung cancer has been transformed from a rare disease into a global problem and public health issue. The etiologic factors of lung cancer become more complex along with industrialization, urbanization, and environmental pollution around the world. Currently, the control of lung cancer has attracted worldwide attention. Studies on the epidemiologic characteristics of lung cancer and its relative risk factors have played an important role in the tertiary prevention of lung cancer and in exploring new ways of diagnosis and treatment. This article reviews the current evolution of the epidemiology of lung cancer. PMID:27261907

  13. [Future prospects of molecular epidemiology in tuberculosis].

    PubMed

    Matsumoto, Tomoshige; Iwamoto, Tomotada

    2009-12-01

    Before the availability of high-resolution genotyping tools in 1990s, there was a prevailing dogma of little genomic sequence diversity in Mycobacterium tuberculosis. Due to the low levels of genetic variation, it was assumed that M. tuberculosis exhibit very little phenotypic variation in immunologic and virulence factors. The fingerprinting method based on restriction fragment length polymorphisms (RFLP) of IS6110 insertion sequences had unveiled the underestimation of the sequence variation in M. tuberculosis and the importance of strain-to-strain variation for understanding pathogenesis, immune mechanisms, bacterial evolution, and host adaptation. This method became a gold standard for strain differentiation in the molecular epidemiological study. It had lead to a profusion of studies in molecular epidemiology such as the detection of unsuspected transmission, the estimation of the extent of recent transmission, the identification of laboratory cross-contamination, the identification of outbreaks, and distinction between reinfection and relapse. This, in 1990s, is the opening of the molecular epidemiology of tuberculosis. After the completion of genome project of the M. tuberculosis laboratory strain H37Rv, some of the clinical isolates were completely sequenced. This prompted the in silico genome comparison and identified various genomic markers which can give a unifying framework for both epidemiology and evolutionary analysis of M. tuberculosis population. Of them, variable numbers of tandem repeats (VNTR) was found as the most promising PCR-based method which can provide adequate discrimination of M. tuberculosis strains in many cases, including the estimation of M. tuberculosis transmission and the identification of genetic lineages. PCR-based VNTR analysis is easy, rapid, and highly specific and can generate portable digit-based data, unlike the analog information obtained from IS6110 RFLP which is labor intensive. In this regards, investigators can

  14. 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.

  15. 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

  16. 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…

  17. Phylogenetically resolving epidemiologic linkage.

    PubMed

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

    2016-03-01

    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

  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. [Toxoplasmosis: Epidemiology, Diagnosis, Treatment].

    PubMed

    Khryanin, A A; Reshetnikov, O V; Kuvshinova, I N

    2015-01-01

    The up-to-date literature and original data on the epidemiology, diagnosis and treatment of toxoplasmosis are presented. Particular attention is paid to the parasite infection during pregnancy. Spiramycin is the drug of choice for acute toxoplasmosis in pregnant women.

  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. The need for epidemiological research in road trauma.

    PubMed

    Wigglesworth, E C

    1979-04-01

    This paper discusses the application of epidemiological methods to the public health problem of road trauma. The complex nature of the system is stressed, and some consequent difficulties in the formulation of appropriate hypotheses are outlined. Examples are given. To solve these problems, the paper proposes the formation of multidisciplinary full-time epidemiological research teams.

  2. EPI-CT: design, challenges and epidemiological methods of an international study on cancer risk after paediatric and young adult CT.

    PubMed

    Bosch de Basea, Magda; Pearce, Mark S; Kesminiene, Ausrele; Bernier, Marie-Odile; Dabin, Jérémie; Engels, Hilde; Hauptmann, Michael; Krille, Lucian; Meulepas, Johanna M; Struelens, Lara; Baatout, Sarah; Kaijser, Magnus; Maccia, Carlo; Jahnen, Andreas; Thierry-Chef, Isabelle; Blettner, Maria; Johansen, Christoffer; Kjaerheim, Kristina; Nordenskjöld, Arvid; Olerud, Hilde; Salotti, Jane A; Andersen, Tina Veje; Vrijheid, Martine; Cardis, Elisabeth

    2015-09-01

    Computed tomography (CT) has great clinical utility and its usage has increased dramatically over the years. Concerns have been raised, however, about health impacts of ionising radiation exposure from CTs, particularly in children, who have a higher risk for some radiation induced diseases. Direct estimation of the health impact of these exposures is needed, but the conduct of epidemiological studies of paediatric CT populations poses a number of challenges which, if not addressed, could invalidate the results. The aim of the present paper is to review the main challenges of a study on the health impact of paediatric CTs and how the protocol of the European collaborative study EPI-CT, coordinated by the International Agency for Research on Cancer (IARC), is designed to address them. The study, based on a common protocol, is being conducted in Belgium, Denmark, France, Germany, the Netherlands, Norway, Spain, Sweden and the United Kingdom and it has recruited over one million patients suitable for long-term prospective follow-up. Cohort accrual relies on records of participating hospital radiology departments. Basic demographic information and technical data on the CT procedure needed to estimate organ doses are being abstracted and passive follow-up is being conducted by linkage to population-based cancer and mortality registries. The main issues which may affect the validity of study results include missing doses from other radiological procedures, missing CTs, confounding by CT indication and socioeconomic status and dose reconstruction. Sub-studies are underway to evaluate their potential impact. By focusing on the issues which challenge the validity of risk estimates from CT exposures, EPI-CT will be able to address limitations of previous CT studies, thus providing reliable estimates of risk of solid tumours and leukaemia from paediatric CT exposures and scientific bases for the optimisation of paediatric CT protocols and patient protection. PMID:26226081

  3. 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. PMID:24022890

  4. Causation: the elusive grail of epidemiology.

    PubMed

    Karhausen, L R

    2000-01-01

    The paper discusses the evolving concept of causation in epidemiology and its potential interaction with logic and scientific philosophy. Causes are contingent but the necessity which binds them to their effects relies on contrary-to-fact conditionals, i.e. conditional statements whose antecedent is false. Chance instead of determinism plays a growing role in science and, although rarely acknowledged yet, in epidemiology: causes are multiple and chancy; a prior event causes a subsequent event if the probability distribution of the subsequent event changes conditionally upon the probability of the prior event. There are no known sufficient causes in epidemiology. We merely observe tendencies toward sufficiency or tendencies toward necessity: cohort studies evaluate the first tendencies, and case-control studies the latter. In applied sciences, such as medicine and epidemiology, causes are intrinsically connected with goals and effective strategies: they are recipe which have a potential harmful or successful use; they are contrastive since they make a difference between circumstances in which they are present and those in which they are absent: causes do not explain event E but event E rather than even F. Causation is intrinsically linked with the notion of "what is pathological". Any definition of causation will inevitably collapse into the use made of epidemiologic methods. The progressive methodological sophistication of the last forty years is in perfect alignment with a gradual implicit overhaul of our concept of causation. PMID:11080970

  5. 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.

  6. 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".

  7. 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...

  8. 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…

  9. [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.

  10. 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

  11. Dengue: update on epidemiology.

    PubMed

    Wilson, Mary Elizabeth; Chen, Lin H

    2015-01-01

    The epidemiology of dengue fever has undergone major shifts in recent decades. The global distribution has expanded to include more geographic areas. The intensity of transmission and the severity of infections have increased in areas where infection was already endemic. Multiple studies provide a clearer picture of the epidemiology and allow mapping of its distribution and change over time. Despite major efforts to control transmission, competent vectors now infest most tropical and subtropical regions; Aedes albopictus, also a competent vector, is able to survive in temperate areas, placing parts of Europe and North America at risk for local transmission. Many research teams in dengue-endemic areas are working to identify key local weather, vector, and other variables that would allow prediction of a likely epidemic early enough to permit interventions to avert it or blunt its impact.

  12. 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

  13. Measurement issues in environmental epidemiology.

    PubMed Central

    Hatch, M; Thomas, D

    1993-01-01

    This paper deals with the area of environmental epidemiology involving measurement of exposure and dose, health outcomes, and important confounding and modifying variables (including genotype and psychosocial factors). Using examples, we illustrate strategies for increasing the accuracy of exposure and dose measurement that include dosimetry algorithms, pharmacokinetic models, biologic markers, and use of multiple measures. Some limitations of these methods are described and suggestions are made about where formal evaluation might be helpful. We go on to discuss methods for assessing the inaccuracies in exposure or dose measurements, including sensitivity analysis and validation studies. In relation to measurement of health outcomes, we discuss some definitional issues and cover, among other topics, biologic effect markers and other early indicators of disease. Because measurement error in covariates is also important, we consider the problems in measurement of common confounders and effect modifiers. Finally, we cite some general methodologic research needs. PMID:8206042

  14. 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

  15. [Acute coronary syndromes: epidemiology].

    PubMed

    Ozkan, Alev Arat

    2013-04-01

    Coronary heart disease is the main cause of death in the world as well as in Turkey. It's not only a health issue but also a social problem with a high economic burden and negative impact on quality of life. The majority of deaths are attributable to acute coronary syndromes (ACS) and their complications.This review summarizes some important facts regarding ACS epidemiology in the world and in Turkey. PMID:27323430

  16. [From molecular to genomic and metagenomic epidemiology].

    PubMed

    Zhebrun, A B

    2014-01-01

    The notion "molecular epidemiology" was introduced into scientific literature by Kilburn E. et al. in 1973. The first period of development of infectious diseases molecular epidemiology may be called "genotypic" (1980-1990s). During this period methodology of molecular marking of pathogens for purposes of monitoring of their spread and outbreak detection (novel nomenclature of diphtheria corynebacteria based on ribotyping; international network PulseNet for monitoring food source infections; international database of tuberculosis mycobacteria spoligotypes) was created. The second--"genomic" period started in the 2000s. Molecular epidemiology rapidly went through single markers (genotypes or single genes) to deciphering the whole genome of pathoge "mobileome", "resistome", "virulome" etc. took an important place in the studies of emerging and pandemic infections. Knowledge on genetic mechanisms leading to emergence and global dissemination of novel pathogens give molecular epidemiology its own scientific content and transforms it from a methodical approach to an independent field of epidemiology. The third--"metagenomic" period starts nowadays based on meta-genomic approach that allows to determine the whole set ofgenomes in the studied sample without the cultivation procedure. In the short-term this would lead to a change of a century-long paradigm of diagnostics and control of infections: instead of search of separate (key) pathogens--characteristics of the full specter of microorganisms in the material from patients and environmental samples with its identification up to any taxonomic depth. In the systems of regional and global epidemiologic control a universal monitoring of all known and re-emerging pathogens with construction and maintenance of metagenomic passports of human habitats will be realized. PMID:25286516

  17. [From molecular to genomic and metagenomic epidemiology].

    PubMed

    Zhebrun, A B

    2014-01-01

    The notion "molecular epidemiology" was introduced into scientific literature by Kilburn E. et al. in 1973. The first period of development of infectious diseases molecular epidemiology may be called "genotypic" (1980-1990s). During this period methodology of molecular marking of pathogens for purposes of monitoring of their spread and outbreak detection (novel nomenclature of diphtheria corynebacteria based on ribotyping; international network PulseNet for monitoring food source infections; international database of tuberculosis mycobacteria spoligotypes) was created. The second--"genomic" period started in the 2000s. Molecular epidemiology rapidly went through single markers (genotypes or single genes) to deciphering the whole genome of pathoge "mobileome", "resistome", "virulome" etc. took an important place in the studies of emerging and pandemic infections. Knowledge on genetic mechanisms leading to emergence and global dissemination of novel pathogens give molecular epidemiology its own scientific content and transforms it from a methodical approach to an independent field of epidemiology. The third--"metagenomic" period starts nowadays based on meta-genomic approach that allows to determine the whole set ofgenomes in the studied sample without the cultivation procedure. In the short-term this would lead to a change of a century-long paradigm of diagnostics and control of infections: instead of search of separate (key) pathogens--characteristics of the full specter of microorganisms in the material from patients and environmental samples with its identification up to any taxonomic depth. In the systems of regional and global epidemiologic control a universal monitoring of all known and re-emerging pathogens with construction and maintenance of metagenomic passports of human habitats will be realized.

  18. 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. PMID:25161995

  19. myEpi. Epidemiology of One

    PubMed Central

    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. PMID:25161995

  20. 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.

  1. Qualitative research in clinical epidemiology.

    PubMed

    Gregory, Deborah M; Way, Christine Y

    2015-01-01

    This chapter has been written to specifically address the usefulness of qualitative research for the practice of clinical epidemiology. The methods of grounded theory to facilitate understanding of human behavior and construction of monitoring scales for use in quantitative studies are discussed. In end-stage renal disease patients receiving long-term hemodialysis, a qualitative study used grounded theory to generate a multilayered classification system, which culminated in a substantive theory on living with end-stage renal disease and hemodialysis. The qualitative data base was re-visited for the purpose of scale development and led to the Patient Perception of Hemodialysis Scale (PPHS). The quantitative study confirmed that the PPHS was psychometrically valid and reliable and supported the major premises of the substantive theory. PMID:25694318

  2. Abortion: epidemiology, safety, and technique.

    PubMed

    Blumenthal, P D

    1992-08-01

    In 1991, the abortion literature was characterized by articles relating to 1) epidemiologic issues in abortion care, 2) advances in knowledge and experience with medical abortifacients such as mifepristone (RU 486), and 3) cervical ripening prior to abortion with the use of both mifepristone and prostaglandins. Technical methods of achieving termination of pregnancy continue to be similar in the United States, the United Kingdom, and Europe, although induction-abortion times are generally slower in Europe than in the United States. Surgically, dilatation and evacuation procedures continue to be more common in the United States than in other countries. The effectiveness of mifepristone is undisputed, and the recommended dose for early first-trimester termination is being compared with lower dose alternative regimens. There is additional evidence that at least in the short term, the negative psychological sequelae of abortion are infrequent and are inconsequential as a public health issue. PMID:1504270

  3. Race, racism, and epidemiological surveys.

    PubMed

    Adebimpe, V R

    1994-01-01

    Many studies of clinical populations have reported significant differences between whites and blacks in prevalence rates of mental disorders. However, data from the Epidemiologic Catchment Area study indicate only modest differences. The author describes factors in the treatment experiences of black and white patients that may lead researchers to find questionable disparities in prevalence rates. These factors include racial differences in treatment-seeking behavior, likelihood of involuntary commitment, representation in research samples, presentation of psychiatric symptoms and resulting diagnoses, and accuracy of psychological tests as well as disparities in treatment. The author suggests guidelines for improving research methods and designs, including documenting the ethnic composition of samples and using structured diagnostic assessments, so that unintended inequalities can be identified, addressed, and monitored and the accuracy of prevalence data among blacks can be improved.

  4. Qualitative research in clinical epidemiology.

    PubMed

    Gregory, Deborah M; Way, Christine Y

    2015-01-01

    This chapter has been written to specifically address the usefulness of qualitative research for the practice of clinical epidemiology. The methods of grounded theory to facilitate understanding of human behavior and construction of monitoring scales for use in quantitative studies are discussed. In end-stage renal disease patients receiving long-term hemodialysis, a qualitative study used grounded theory to generate a multilayered classification system, which culminated in a substantive theory on living with end-stage renal disease and hemodialysis. The qualitative data base was re-visited for the purpose of scale development and led to the Patient Perception of Hemodialysis Scale (PPHS). The quantitative study confirmed that the PPHS was psychometrically valid and reliable and supported the major premises of the substantive theory.

  5. Trichinosis: Epidemiology in Thailand

    PubMed Central

    Kaewpitoon, Natthawut; Kaewpitoon, Soraya Jatesadapattaya; Philasri, Chutikan; Leksomboon, Ratana; Maneenin, Chanvit; Sirilaph, Samaporn; Pengsaa, Prasit

    2006-01-01

    Trichinosis is one of the most common food-borne parasitic zoonoses in Thailand and many outbreaks are reported each year. This paper reviews the history, species, and epidemiology of the disease and food habits of the people with an emphasis on the north, northeast, central and south regions of Thailand. The earliest record of trichinosis in Thailand was in 1962 in the Mae Sariang District, Mae Hong Son Province. Since then, about 130 outbreaks have been reported involving 7392 patients and 97 deaths (1962-2005). The highest number of cases, 557, was recorded in 1983. The annual epidemiological surveillance reports of the Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health, Thailand, show that trichinosis cases increased from 61 in 1997 to 351 in 1998. In contrast to these figures, the number of reported cases decreased to 16 in 1999 and 128 cases in 2000. There was no record of trichinosis in 2001, but then the figures for 2002, 2003 and 2004 were 289, 126 and 212 respectively. The infected patients were mostly in the 35-44 years age group and the disease occurred more frequently in men than women at a ratio of 1.7-2.0:1. There were 84 reported cases of trichinosis in Chiang Rai, Nan, Chiang Mai, Si Sa ket, Nakhon Phanom, Kalasin, Nakhon Ratchasima, Nakhon Nayok, Nakhon Pathom and Surat Thani, provinces located in different parts of Thailand in 2005. The outbreaks were more common in the northern areas, especially in rural areas where people ate raw or under-cooked pork and/or wild animals. This indicates the need for health education programs to prevent and control trichinosis as soon as possible in the high-risk areas. PMID:17072975

  6. 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.

  7. Migraine headache: epidemiologic perspectives.

    PubMed

    Linet, M S; Stewart, W F

    1984-01-01

    Clinical and epidemiologic studies suggest that a number of factors are associated with the risk of migraine and precipitation of an attack. However, the degree to which causal associations can be inferred from reported studies is very limited and is a result of the methodological problems discussed throughout this review. The study of migraine in many ways parallels the pattern seen in early investigations of other conditions, such as rheumatoid arthritis and systemic lupus erythematosus, because a number of methodological problems had to be resolved in the study of these conditions before significant progress could be made. To achieve significant advances in the improvement of our understanding of the causes of migraine, a number of related issues must be addressed and resolved in future studies. Most noteworthy among these are Recognition of the probable heterogeneity of migraine, not merely in the manifestation of symptoms but, more importantly, in the existence of distinct etiologic subtypes. A number of findings suggest that some migraine subtypes are sensitive to certain precipitants, some appear to be a part of a more generalized constitutional disorder, and some are accompanied by a higher prevalence of migraine among family members. Efforts should be made in understanding the relationship between specific biochemical markers and traits (such as monoamine oxidase deficiency and tyramine sensitivity); precipitants related to the migraine attack; and epidemiologic characteristics such as age at onset and sex. Creation of a more precise, reliable, and practically useful definition of migraine. Without such a definition, it is difficult, if not impossible, to compare results between studies, to understand the relationship between risk factors and migraine subtypes, to understand properly associations identified in selected clinic populations, and, in general, to understand the epidemiology of migraine. More accurate characterization of the case group under

  8. The People's Library of Epidemiology.

    PubMed

    Last, John M

    2012-03-01

    The People's Library of Epidemiology is in the process of development. It consists of a website (http://www.jameslindlibrary.org) with links to online excerpts of papers and monographs of historical and scientific importance in epidemiology and related public health sciences that are held by the library of the Royal College of Physicians of Edinburgh. This paper reflects the lively panel discussion which took place on 9 August 2011. The panel members who opened the discussion were Alfredo Morabia, Anne Hardy, Roger Bernier, Jan Vandenbroucke, George Davey Smith, Esther Villalonga and Stephen Walter, who had won the prize awarded by Epidemiology Monitor for an essay on the People's Library of Epidemiology.

  9. Epidemiology of rickettsial diseases.

    PubMed

    Walker, D H; Fishbein, D B

    1991-05-01

    Rickettsial diseases have a diversity of epidemiologic characteristics reflective of the variety of ecologic situations in which the obligate intracellular bacteria are transmitted to humans. For the spotted fever group (SFG) rickettsiae, Rickettsia typhi, R. tsutsugamushi, Coxiella burnetii, and the human ehrlichial agent, humans are a dead-end host who plays no role in the maintenance of the organism in nature. All rickettsioses exist as zoonoses. Moreover, all rickettsiae are found in infected arthopods, which generally serve as the natural hosts and can transmit the infection to the next generation of ticks, mites, chiggers, or fleas. From our anthropocentric viewpoint, Q fever aerosol infection from parturient animals and Brill-Zinsser disease ignited epidemics of louse-borne epidemic typhus are exceptions. However, silent cycles of C. burnetii in ticks and R. prowazekii in the flying squirrel flea may have maintained these agents in transovarial or enzootic cycles for eons before humans and their domestic animals arrived on the scene. Thus, the epidemiology of rickettsial diseases must be recognized as an unfortunate aberration of the rickettsial economy. Several excellent reviews of rickettsial ecology contain a wealth of useful information. PMID:1884775

  10. 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.

  11. 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

  12. Epidemiology, austerity, and innovation.

    PubMed

    Samet, Jonathan M; Ness, Roberta B

    2012-05-15

    In considering the state of epidemiologic research, these are the "best" and the "worst" of times-the "best" from the perspective of scientific opportunities and the "worst" from the perspective of funding. In this commentary, the authors address this time of funding austerity from the points of view of individual researchers and research institutions. For researchers, the new tools of "-omics," large databases, communication by means of the World Wide Web, and global access offer ever-expanding scientific opportunities. The authors comment on research directions for which there is an enhanced likelihood of funding success: clinical and translational research, outcomes and effectiveness research, and global health research. The authors emphasize the need to be innovative and not bound by the conventional. For institutions, the authors suggest attention to innovation and impact, social networking, and finding the "right size" for training programs. Academic institutions also need to invest, supporting researchers and their ideas. Epidemiologists need to be true to their mission and prove that they can use innovation to advance health and welfare in a measurable way. Doing so will ensure that over the long term, epidemiologic research will remain a cornerstone for advancing population health.

  13. 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.

  14. Epidemiology of bronchioloalveolar carcinoma.

    PubMed

    Falk, R T; Pickle, L W; Fontham, E T; Greenberg, S D; Jacobs, H L; Correa, P; Fraumeni, J F

    1992-01-01

    Descriptive features of bronchioloalveolar carcinoma (BAC) are presented using Surveillance, Epidemiology and End Results Program population-based incidence data from 1973 through 1987, along with risk factors from histologically confirmed cases of BAC identified in a hospital-based case-control study conducted in Louisiana between 1979 and 1982. Compared to the rising incidence of lung cancer overall, BAC rates have remained relatively constant, accounting for less than 3% of all lung cancer. BAC incidence rates were higher in males, yet it explained proportionately more of the total lung cancer incidence in females. In the case-control study, 21 of the 33 cases originally ascertained from hospital pathology records were histologically confirmed as BAC. Most cases smoked cigarettes, with a 4-fold risk for ever smoking. Risks tended to increase with smoking intensity (reaching 10-fold for more than 1.5 packs/day) and duration (reaching 5-fold for more than 45 years of smoking). Following 10 or more years of employment, there was a 4-fold risk associated with motor freight occupations, along with nonsignificant excesses among construction workers, petroleum manufacturers, and sugar cane farmers. Cases were more likely than controls to have had emphysema or to have had a close family member with lung cancer. Although based on small numbers, this study suggests that BAC shares many of the epidemiological characteristics of lung adenocarcinoma.

  15. Epidemiology of Neuroendocrine Tumors.

    PubMed

    Fraenkel, Merav; Faggiano, Antongiulio; Valk, Gerlof D

    2015-01-01

    Formerly named carcinoids, neuroendocrine tumors originate from diffuse endocrine cells, can involve any part of the gastrointestinal tract, endocrine pancreas and bronchopulmonary (BP) tree, and have a wide range of malignant potential. This chapter summarizes the data available on the epidemiology of neuroendocrine neoplasia (NEN) from around the world, including the relative frequency according to organ of origin, annual incidence rates (IR) and trends in IR at the various anatomic sites, age and stage at presentation, racial and gender differences in IR and 5-year survival rates. Over time, changes have been made in the classification and registration of NEN, both in the same registry and across the globe, thus confounding the possibility to draw conclusions as to the true rise in IR of NEN that is observed all over the world. BP NEN has become the most common site in many western countries, while NEN of the rectum is more common in the Far East. In some countries, appendiceal NEN is the most common site in females. When compared to adenocarcinoma of the same location, the prognosis of NEN patients is better. Five-year survival rates are highest for NEN originating in the rectum and appendix, but lower in small intestinal and pancreatic NEN. Future research is needed to understand the contribution of genetic and environmental factors to NEN epidemiology. PMID:26303701

  16. Schizophrenia: from Epidemiology to Rehabilitation

    PubMed Central

    Mura, Gioia; Petretto, Donatella Rita; Bhat, Krishna M; Carta, Mauro Giovanni

    2012-01-01

    Purpose/Objective: We discuss recent evidences about schizophrenia (frequency, onset, course, risk factors and genetics) and their influences to some epidemiological myths about schizophrenia diffuse between psychiatric and psychopathology clinicians. The scope is to evaluate if the new acquisitions may change the rehabilitation approaches to schizophrenia modifying the balance about the neurodevelopmental hypothesis of schizophrenia accepting that the cognitive deficits are produced by errors during the normal development of the brain (neurodevelopmental hypothesis) that remains stable in the course of illness and the neurodegenerative hypothesis according of which they derived from a degenerative process that goes on inexorably. Research Method/Design: A review of the literature about epidemiology of schizophrenia has been performed and the contributions of some of these evidence to neurodevelopmental hypothesis and to rehabilitation has been described. Results: It cannot be definitively concluded for or against the neurodevelopmental or degenerative hypothesis, but efforts in understanding basis of schizophrenia must go on. Until now, rehabilitation programs are based on the vulnerability-stress model: supposing an early deficit that go on stable during the life under favorable circumstances. So, rehabilitation approaches (as neuro-cognitive approaches, social skill training, cognitive-emotional training) are focused on the individual and micro-group coping skills, aiming to help people with schizophrenia to cope with environmental stress factors. Conclusions/Implications: Coping of cognitive deficits in schizophrenia may represents the starting-point for further research on schizophrenia, cohort studies and randomized trials are necessary to defined the range of effectiveness and the outcome of the treatments. PMID:22962559

  17. 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.

  18. 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. PMID:26088071

  19. Ethical issues in epidemiological research.

    PubMed

    Hessel, P A; Fourie, P B

    1987-12-19

    Ethical concerns pervade all aspects of epidemiological investigations. Ethical issues, including planning, carrying out, analysing and presenting the results of a study, are discussed. In southern Africa, where many community-based epidemiological surveys are undertaken, issues relating specifically to the conduct of such studies are especially relevant. These include informed consent, confidentiality and privacy.

  20. 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.

  1. 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.

  2. 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

  3. [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.

  4. [Epidemiological problems of obesity].

    PubMed

    Beiul, E A; Oleneva, V A; Mühr, M; Heller, G M; Popova, Iu P

    1980-01-01

    The results of epidemiological survey of the population living in the middle zone of the Soviet Union and in the GDR are considered. Comparison of the data obtained shows that overweight is a very prevalent abnormal condition among the test population groups in both countries and amounts to 26% (USSR) and 30% (GDR). Excess animal fat consumption in the presence of a decreased quota of vegetable oil has been established and a significant increase in monosaccharides intake noted. Attention is attracted by insufficient quota of fresh vegetables and fruit in the diets of the population of both countries. Qualitative and quantitative nutritional pitfalls were shown to be aggravated in obese people. Violation of dietetic regimens and decreased physical activity play a definite role in the development of overweight. A program on primary and secondary prevention of overweight has been established. It includes a number of measures both common and specific to the GDR and the USSR.

  5. Melanoma Epidemiology and Prevention.

    PubMed

    Berwick, Marianne; Buller, David B; Cust, Anne; Gallagher, Richard; Lee, Tim K; Meyskens, Frank; Pandey, Shaily; Thomas, Nancy E; Veierød, Marit B; Ward, Sarah

    2016-01-01

    The epidemiology of melanoma is complex, and individual risk depends on sun exposure, host factors, and genetic factors, and in their interactions as well. Sun exposure can be classified as intermittent, chronic, or cumulative (overall) exposure, and each appears to have a different effect on type of melanoma. Other environmental factors, such as chemical exposures-either through occupation, atmosphere, or food-may increase risk for melanoma, and this area warrants further study. Host factors that are well known to be important are the numbers and types of nevi and the skin phenotype. Genetic factors are classified as high-penetrant genes, moderate-risk genes, or low-risk genetic polymorphisms. Subtypes of tumors, such as BRAF-mutated tumors, have different risk factors as well as different therapies. Prevention of melanoma has been attempted using various strategies in specific subpopulations, but to date optimal interventions to reduce incidence have not emerged. PMID:26601858

  6. Cancer epidemiology of woodworking.

    PubMed

    Mohtashamipur, E; Norpoth, K; Lühmann, F

    1989-01-01

    The literature published between 1965 and 1989 on the cancer epidemiology of woodworking in furniture industries and carpentry shops in 17 countries is reviewed. Included are some unpublished data obtained through personal communication with epidemiologists or collected from doctoral dissertations. Of 5,785 cases with sino-nasal cancers, about 23% were found to be woodworkers. Dusty jobs, especially wood processing using high-speed machines, are mainly associated with the enhanced incidence of nasal adenocarcinomas. The latency periods of the latter tumors ranged from 7 to 69 years in five European countries. A variety of neoplasias of the respiratory, digestive, and urinary tracts as well as the hemopoietic and lymphatic systems, including Hodgkin's disease are reported to be significantly associated with occupational exposure to wood dust. These data suggest that the exposure to some types of wood dust might cause a systemic rather than local neoplastic disorder.

  7. 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

  8. [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.

  9. Epidemiology of HCV infection.

    PubMed

    Baldo, V; Baldovin, T; Trivello, R; Floreani, A

    2008-01-01

    It is estimated that approximately 130-170 million people worldwide are infected with hepatitis C virus (HCV). According to data from WHO community and blood donor surveys, the African and Eastern Mediterranean countries report the highest prevalence rates (>10%). The rates of infection in the general population and the incidence of newly-acquired cases indicate an appreciable change in the epidemiology of the infection in recent years. Prior to the widespread screening of blood donations, infected blood and blood products represented a common source of infection. On the other hand, the high peak in HCV antibodies among the elderly in Italian epidemiological studies on the population at large reflects a cohort effect due to an epidemic of HCV infection occurring after the Second World War. According to data reported by the CDC Surveillance System, the incidence of acute hepatitis C has declined since the late 1980s. In 2005, as in previous years, the majority of such cases in North America and Northern Europe occurred among young adults and injected drug use was the most common risk factor. Other, less commonly reported modes of HCV acquisition are occupational exposure to blood, high-risk sexual activity, tattooing, body piercing and other forms of skin penetration. Finally, the overall rate of mother-to-child transmission from HCV-infected, HIV-negative mothers has been estimated at around 5% (coinfection with HIV raises this figure to 19.4%). HCV prevention relies on identifying and counseling uninfected persons at risk of contracting hepatitis C. PMID:18673187

  10. Epidemiology of acne vulgaris.

    PubMed

    Bhate, K; Williams, H C

    2013-03-01

    Despite acne being an almost universal condition in younger people, relatively little is known about its epidemiology. We sought to review what is known about the distribution and causes of acne by conducting a systematic review of relevant epidemiological studies. We searched Medline and Embase to the end of November 2011. The role of Propionibacterium acnes in pathogenesis is unclear: antibiotics have a direct antimicrobial as well as an anti-inflammatory effect. Moderate-to-severe acne affects around 20% of young people and severity correlates with pubertal maturity. Acne may be presenting at a younger age because of earlier puberty. It is unclear if ethnicity is truly associated with acne. Black individuals are more prone to postinflammatory hyperpigmentation and specific subtypes such as 'pomade acne'. Acne persists into the 20s and 30s in around 64% and 43% of individuals, respectively. The heritability of acne is almost 80% in first-degree relatives. Acne occurs earlier and is more severe in those with a positive family history. Suicidal ideation is more common in those with severe compared with mild acne. In the U.S.A., the cost of acne is over 3 billion dollars per year in terms of treatment and loss of productivity. A systematic review in 2005 found no clear evidence of dietary components increasing acne risk. One small randomized controlled trial showed that low glycaemic index (GI) diets can lower acne severity. A possible association between dairy food intake and acne requires closer scrutiny. Natural sunlight or poor hygiene are not associated. The association between smoking and acne is probably due to confounding. Validated core outcomes in future studies will help in combining future evidence.

  11. 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.

  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. Phylodynamic inference for structured epidemiological models.

    PubMed

    Rasmussen, David A; Volz, Erik M; Koelle, Katia

    2014-04-01

    Coalescent theory is routinely used to estimate past population dynamics and demographic parameters from genealogies. While early work in coalescent theory only considered simple demographic models, advances in theory have allowed for increasingly complex demographic scenarios to be considered. The success of this approach has lead to coalescent-based inference methods being applied to populations with rapidly changing population dynamics, including pathogens like RNA viruses. However, fitting epidemiological models to genealogies via coalescent models remains a challenging task, because pathogen populations often exhibit complex, nonlinear dynamics and are structured by multiple factors. Moreover, it often becomes necessary to consider stochastic variation in population dynamics when fitting such complex models to real data. Using recently developed structured coalescent models that accommodate complex population dynamics and population structure, we develop a statistical framework for fitting stochastic epidemiological models to genealogies. By combining particle filtering methods with Bayesian Markov chain Monte Carlo methods, we are able to fit a wide class of stochastic, nonlinear epidemiological models with different forms of population structure to genealogies. We demonstrate our framework using two structured epidemiological models: a model with disease progression between multiple stages of infection and a two-population model reflecting spatial structure. We apply the multi-stage model to HIV genealogies and show that the proposed method can be used to estimate the stage-specific transmission rates and prevalence of HIV. Finally, using the two-population model we explore how much information about population structure is contained in genealogies and what sample sizes are necessary to reliably infer parameters like migration rates. PMID:24743590

  14. Snippets From the Past: The Evolution of Wade Hampton Frost's Epidemiology as Viewed From the American Journal of Hygiene/Epidemiology

    PubMed Central

    Morabia, Alfredo

    2013-01-01

    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. PMID:24022889

  15. 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.

  16. Culture-Independence for Surveillance and Epidemiology

    PubMed Central

    Kirkup, Benjamin C.

    2013-01-01

    Culture-independent methods in microbiology (quantitative PCR (qPCR), sequencing, microarrays, direct from sample matrix assisted laser desorption/ionization time of flight mass spectroscopy (MALDI-TOF MS), etc.) are disruptive technology. Rather than providing the same results as culture-based methods more quickly, more cheaply or with improved accuracy, they reveal an unexpected diversity of microbes and illuminate dark corners of undiagnosed disease. At times, they overturn existing definitions of presumably well-understood infections, generating new requirements for clinical diagnosis, surveillance and epidemiology. However, current diagnostic microbiology, infection control and epidemiology rest principally on culture methods elegantly optimized by clinical laboratorians. The clinical significance is interwoven; the new methods are out of context, difficult to interpret and impossible to act upon. Culture-independent diagnostics and surveillance methods will not be deployed unless the reported results can be used to select specific therapeutics or infection control measures. To cut the knots surrounding the adoption of culture-independent methods in medical microbiology, culture-dependent methods should be supported by consistent culture-independent methods providing the microbial context. This will temper existing biases and motivate appropriate scrutiny of the older methods and results. PMID:25437208

  17. 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

  18. 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. PMID:27652213

  19. 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.

  20. Intelligent management of epidemiologic data.

    PubMed Central

    Ferri, F.; Evoli, L. M.; Pisanelli, D. M.; Ricci, F. L.

    1991-01-01

    In the lifecycle of epidemiologic data three steps can be identified: production, interpretation and exploitation for decision. Computerized support can be precious, if not indispensable, at any of the three levels, therefore several epidemiologic data management systems were developed. In this paper we focus on intelligent management of epidemiologic data, where intelligence is needed in order to analyze trends or to compare observed with reference value and possibly detect abnormalities. After having outlined the problems involved in such a task, we show the features of ADAMS, a system realized to manage aggregated data and implemented in a personal computer environment. PMID:1807619

  1. 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.

  2. Epidemiological models of Mycobacterium tuberculosis complex infections.

    PubMed

    Ozcaglar, Cagri; Shabbeer, Amina; Vandenberg, Scott L; Yener, Bülent; Bennett, Kristin P

    2012-04-01

    The resurgence of tuberculosis in the 1990s and the emergence of drug-resistant tuberculosis in the first decade of the 21st century increased the importance of epidemiological models for the disease. Due to slow progression of tuberculosis, the transmission dynamics and its long-term effects can often be better observed and predicted using simulations of epidemiological models. This study provides a review of earlier study on modeling different aspects of tuberculosis dynamics. The models simulate tuberculosis transmission dynamics, treatment, drug resistance, control strategies for increasing compliance to treatment, HIV/TB co-infection, and patient groups. The models are based on various mathematical systems, such as systems of ordinary differential equations, simulation models, and Markov Chain Monte Carlo methods. The inferences from the models are justified by case studies and statistical analysis of TB patient datasets. PMID:22387570

  3. 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

  4. 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. PMID:25737091

  5. The epidemiology and economic consequences of pain.

    PubMed

    Henschke, Nicholas; Kamper, Steven J; Maher, Chris G

    2015-01-01

    Pain is considered a major clinical, social, and economic problem in communities around the world. In this review, we describe the incidence, prevalence, and economic burden of pain conditions in children, adolescents, and adults based on an electronic search of the MEDLINE and EMBASE databases for articles published from January 1, 2000, through August 1, 2014, using the keywords pain, epidemiology, burden, prevalence, and incidence. The impact of pain on individuals and potential risk factors are also discussed. Differences in the methodology and conduct of epidemiological studies make it difficult to provide precise estimates of prevalence and incidence; however, the burden of pain is unquestionably large. Improved concepts and methods are needed in order to study pain from a population perspective and further the development of pain prevention and management strategies. PMID:25572198

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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. PMID:25241267

  12. AIDS in women: epidemiology.

    PubMed

    Willoughby, A

    1989-09-01

    Several facts concerning the distribution of AIDS in U.S. female populations are clear. This disease has made significant inroads, in a quantitative sense, into the female segment of our society as documented by AIDS surveillance data, information on pregnant women and parturients, and by screening data from the military. The impact on women in the reproductive years, on the reproductive health of these women, and on the reproductive outcome of their pregnancies is of substantial concern. Monitoring epidemiologic trends in certain groups will require clever and creative strategies like those of Hoff and colleagues. Additional data may be derived from the CDC's Family of Surveys that will examine HIV prevalence in five groups (in addition to the newborn infant survey described above): intravenous drug users, patients admitted to hospitals, sexually transmitted disease clinic patients, women's health and reproductive health clinics, and tuberculosis clinics. It is hoped that the data obtained from these studies, as well as data gathered on college students and Job Corps applicants, will contribute additional information on HIV infection in women. Monitoring the progress of the AIDS epidemic in women will be difficult. Even more difficult will be the effort to respond to the epidemic in the women it most frequently affects: the poor, minority, disenfranchised women who may be involved in illegal activities (drug use, prostitution, illegal immigration) who are not well networked into the medical and social services of our society. PMID:2776374

  13. Shigellosis: Epidemiology in India.

    PubMed

    Taneja, Neelam; Mewara, Abhishek

    2016-05-01

    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

  14. Epidemiology of clavicle fractures.

    PubMed

    Postacchini, Franco; Gumina, Stefano; De Santis, Pierfrancesco; Albo, Francesco

    2002-01-01

    An epidemiologic study of 535 isolated clavicle fractures treated in a hospital of a large metropolis during an 11-year period was performed. Data regarding patient's age and sex, side involved, mechanism of injury, and season in which the fracture occurred were obtained from the clinical records. Radiographic classification was performed with the Allman system. Clavicle fractures represented 2.6% of all fractures and 44% of those in the shoulder girdle. Most patients were men (68%), and the left side was involved in 61% of cases. Fractures of the middle third of the clavicle, which were the most common (81%), were displaced in 48% of cases and comminuted in 19%. Fractures of the medial third were the least common (2%). The prevalence of midclavicular fractures was found to decrease progressively with age, starting from the first decade of life when they represented 88.2% of all clavicle fractures and were undisplaced in 55.5% of cases. In adults, the incidence of displaced fractures, independent of location, was higher than that of undisplaced fractures. Traffic accidents were the most common cause of the injury. In the period under study, the incidence of fractures showed no significant change over time and no seasonal variation. PMID:12378163

  15. [Epidemiology of teeth hypersensitivity].

    PubMed

    Lutskaia, I K; Zinovenko, O G; Kovalenko, I P

    2015-01-01

    A clinical examination of 98 patients aged 20 to 75 years was carried out to identifyclinical and epidemiological features of hard tooth tissueshypersensitivity. The survey found out what stimuli (cold, hot, sour, mechanical, chemical) cause the appearance of dental hyperesthesia. The detailed survey of the affected area aimed to determine the presence of dental caries, gingival recession, wedge-shaped defects, erosions, microcracks and chipped enamel, as well as wear of the tooth crown. Forty-threepatients of 98 (43.88%) had tooth sensitivity. Most affected age group was 25-34 years (33%). Among patients studied with hyperesthesia 86% complained of pain. It was establishedthat dental hyperesthesia most often causes an intense, but quickly passing pain response, wherein upon exposure of several types of stimuli. Teeth with high sensitivity showed signs of abrasion (74.1%), most often--on the vestibular surface (44.4%). Patients under 45 years had notable cracks and wedge-shaped defects. In patients 45 years and older cracks and increased abrasion of hard dental tissues was seen. PMID:26271696

  16. 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.

  17. Culturally Safe Epidemiology: Oxymoron or Scientific Imperative1

    PubMed Central

    Cameron, Mary; Andersson, Neil; McDowell, Ian; Ledogar, Robert J

    2010-01-01

    Since the early 20th Century, epidemiological research has brought benefits and burdens to Aboriginal communities in Canada. Many First Nations, Métis, and Inuit continue to view Western research with distrust; quantitative methods are perceived as especially inconsistent with indigenous ways of knowing. There is increasing recognition, however, that rigorous epidemiological research can produce evidence that draws attention and resources to pressing health issues in Aboriginal communities. We present a framework for culturally safe epidemiology, from the identification of research priorities, through fieldwork and analysis, to communication and use of evidence. Modern epidemiology and indigenous knowledge are not inherently discordant; many public health opportunities arise at this interface and good science must begin here too. PMID:20975852

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. [Epidemiology between ethics and politics].

    PubMed

    Saracci, R

    1999-01-01

    Over the last two decades ethics in epidemiology has been the subject of a substantial number of conferences, books, articles, guidelines as well as training courses. The relevance of ethics for epidemiology does not make the ethical approach sufficient to exhaust the analysis of the relationship between epidemiology and society: on one side the ethical assessment of an epidemiological investigation is not self-sufficient but depends on the evaluation of the scientific worth of the study (a planned study involving humans is automatically unethical if scientifically unsound) and, on the other side, to be of practical value it needs expanding as to its policy implications. A few remarks on two issues, ethics committees and human reproductive cloning, support the general contention that translating knowledge into effective public health actions may be grounded in ethical considerations but necessitates a substantial development at political level.

  3. 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. PMID:24229634

  4. [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.

  5. [Molecular epidemiology of the Methicillin-resistant Staphylococcus aureus(MRSA) by the internal transcribed spacer PCR (ITS-PCR) method and the phage open reading frame typing (POT) method].

    PubMed

    Senda, Yasuko; Takemori, Yukiko; Iwata, Yasunori; Fujita, Shinichi; Sakai, Yoshio; Wada, Takashi

    2014-05-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is the most common causative bacteria of hospital acquired infection, and should be rapidly identified for infection control. For this purpose, in our hospital, the PCR electrophoresis patterns of spacer regions (ITS: internal transcribed spacers) (ITS-PCR) are combined with a toxigenicity assay to establish a strain identification method for outbreak surveillance. In the present study, the usefulness of this method was evaluated in comparison with the POT (phage-open reading frame typing) method. One hundred MRSA strains isolated from inpatients in our hospital between April 2011 and March 2012 were classified into 25 patterns using the ITS-PCR method combined with a toxigenicity assay. The strains could be classified into 46 patterns using the POT method. ITS-PCR type 22 strain producing enterotoxin C and toxic shock syndrome toxin-1 could be further classified into 7 patterns using the POT method. In the outbreak of the type 22 strain, cross-infection could be excluded by additional analysis using the POT method, providing more precise information on strain identification. We identified that some strains of the same POT type consisted of different ITS-PCR types or toxigenicities. Therefore, these results suggest that the combination of ITS-PCR method plus toxigenicity assay with POT method may be a useful technique of MRSA typing.

  6. 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

  7. [Air pollution and the lung: epidemiological approach].

    PubMed

    Annesi-Maesano, Isabella; Dab, William

    2006-01-01

    Epidemiological evidence has concurred with clinical and experimental evidence to correlate current levels of ambient air pollution, both indoors and outdoors, with respiratory effects. In this respect, the use of specific epidemiological methods has been crucial. Common outdoor pollutants are particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and ozone. Short-term effects of outdoor air pollution include changes in lung function, respiratory symptoms and mortality due to respiratory causes. Increase in the use of health care resources has also been associated with short-term effects of air pollution. Long-term effects of cumulated exposure to urban air pollution include lung growth impairment, chronic obstructive pulmonary disease (COPD), lung cancer, and probably the development of asthma and allergies. Lung cancer and COPD have been related to a shorter life expectancy. Common indoor pollutants are environmental tobacco smoke, particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and biological allergens. Concentrations of these pollutants can be many times higher indoors than outdoors. Indoor air pollution may increase the risk of irritation phenomena, allergic sensitisation, acute and chronic respiratory disorders and lung function impairment. Recent conservative estimates have shown that 1.5-2 million deaths per year worldwide could be attributed to indoor air pollution. Further epidemiological research is necessary to better evaluate the respiratory health effects of air pollution and to implement protective programmes for public health.

  8. Malaria Molecular Epidemiology: Lessons from the International Centers of Excellence for Malaria Research Network.

    PubMed

    Escalante, Ananias A; Ferreira, Marcelo U; Vinetz, Joseph M; Volkman, Sarah K; Cui, Liwang; Gamboa, Dionicia; Krogstad, Donald J; Barry, Alyssa E; Carlton, Jane M; van Eijk, Anna Maria; Pradhan, Khageswar; Mueller, Ivo; Greenhouse, Bryan; Pacheco, M Andreina; Vallejo, Andres F; Herrera, Socrates; Felger, Ingrid

    2015-09-01

    Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts.

  9. Malaria Molecular Epidemiology: Lessons from the International Centers of Excellence for Malaria Research Network

    PubMed Central

    Escalante, Ananias A.; Ferreira, Marcelo U.; Vinetz, Joseph M.; Volkman, Sarah K.; Cui, Liwang; Gamboa, Dionicia; Krogstad, Donald J.; Barry, Alyssa E.; Carlton, Jane M.; van Eijk, Anna Maria; Pradhan, Khageswar; Mueller, Ivo; Greenhouse, Bryan; Andreina Pacheco, M.; Vallejo, Andres F.; Herrera, Socrates; Felger, Ingrid

    2015-01-01

    Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts. PMID:26259945

  10. Epidemiologic studies based on the Chernobyl accident

    SciTech Connect

    Beebe, G.

    1996-12-31

    There are great opportunities in the post-Chernobyl experience for significant epidemiologic research, perhaps even more in the area of disaster research than in the area of the human health effects of ionizing radiation. But the potential opportunity for learning the effects of radioiodine on the thyroid is very great and has aroused widespread national and international investigative interest. The opportunities for significant epidemiologic research are, however, severely limited currently by the worsening economic situation in Belarus and Ukraine, where the greatest exposure occurred, and by the lack of personnel trained in appropriate methods of study, the lack of modern equipment, the lack of supplies, the poor communication facilities, and the difficulties of accurate dose estimation. the disadvantages may or may not outweigh the obvious advantages of large numbers, the extensive direct thyroidal measurements made shortly after the accident in 1986, the magnitude of the releases of radioiodine, and the retention of the former Soviet system of universal medical care. Both the European Commission (EC) and the World Health Organization (WHO) have been working actively to strengthen the infrastructure of Russia, Belarus, and Ukraine. New scientific knowledge has yet to emerge from the extensive epidemiologic work but information of considerable public health significance has begun to accumulate. The bulk of the thyroid cancer has been shown to be valid by international pathology review; both EC and WHO representatives have declared the increase in thyroid cancer among children to have been caused in large part by Chernobyl. No increase in leukemia has been seen in the general population. The WHO pilot studies have shown no evidence of an increase in psychologic or neurologic complications among those exposed in utero. Ongoing epidemiologic work can be described by review of the inventory that the WHO has begun to maintain and publish. 20 refs., 7 tabs.

  11. 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

  12. Analysis of bronchial reactivity in epidemiological studies.

    PubMed Central

    Abramson, M J; Saunders, N A; Hensley, M J

    1990-01-01

    The measurement of bronchial reactivity in epidemiological studies has the advantage of quantifying an objective physiological feature of asthma. Bronchial reactivity was developed in a clinical setting and has been conventionally expressed as the dose of agonist producing a 20% fall in FEV1 (PD20). As PD20 can be estimated for less than 20% of subjects in general community surveys with the doses of agonist that are usually given, data from most subjects must be censored. Thus PD20 alone is a poor index of bronchial reactivity for epidemiological studies. Data from 809 aluminium smelter workers were used to evaluate alternative methods of analysing bronchial reactivity. Dose-response relationships were analysed by four methods: (1) PD20 by the conventional method of interpolating the dose on a logarithmic scale between the last two measurements of FEV1; (2) PD20 (with allowance for extrapolation), estimated by fitting an exponential curve to the dose-response data; (3) the linear regression slope between dose and FEV1 when significant; (4) the dose-response slope obtained in all subjects as the % change in FEV1 from baseline in response to total dose. When each of these measures was related to symptoms, diagnosis, and treatment of asthma, all differentiated between "asthmatic" and "non-asthmatic" subjects. The dose-response slope (method 4) had the advantages of simplicity and no censored data, and was shown to be clinically relevant. It is suggested that the dose-response slope should be used for the analysis of bronchial reactivity in epidemiological studies. PMID:2281424

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

    DOE PAGES

    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 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

  14. 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

  15. A Bayesian ensemble approach for epidemiological projections.

    PubMed

    Lindström, Tom; Tildesley, Michael; Webb, Colleen

    2015-04-01

    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.

  16. 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

  17. Epidemiology of childhood peanut allergy.

    PubMed

    Dyer, Ashley A; Rivkina, Victoria; Perumal, Dhivya; Smeltzer, Brandon M; Smith, Bridget M; Gupta, Ruchi S

    2015-01-01

    Although peanut allergy is among the most common food allergies, no study has comprehensively described the epidemiology of the condition among the general pediatric population. Our objective was to better characterize peanut allergy prevalence, diagnosis trends, and reaction history among affected children identified from a representative sample of United States households with children. A randomized, cross sectional survey was administered to parents from June 2009 to February 2010. Data from 38,480 parents were collected and analyzed in regard to demographics, allergic symptoms associated with food ingestion, and methods of food allergy diagnosis. Adjusted models were estimated to examine association of these characteristics with odds of peanut allergy. Of the 3218 children identified with food allergy, 754 (24.8%) were reported to have a peanut allergy. Peanut allergy was reported most often among 6- to 10-year-old children (25.5%), white children (47.7%), and children from households with an annual income of $50,000-$99,999 (41.7%). Although peanut allergy was diagnosed by a physician in 76% of cases, significantly more peanut allergy reactions were severe as compared with reactions to other foods (53.7% versus 41.0%, p < 0.001). Parents were significantly less likely to report tolerance to peanut as compared with the odds of tolerance reported for other foods (odds ratio 0.7, 95% confidence interval: 0.5-0.9). Childhood peanut allergy, which represents nearly a quarter of all food allergy, presents more severe reactions and is least likely to be outgrown. Although it is diagnosed by a physician in nearly three-fourths of all cases, socioeconomic disparities in regard to diagnosis persist.

  18. 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

  19. 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

  20. Sarcopenia: definition, epidemiology, and pathophysiology.

    PubMed

    Kim, Tae Nyun; Choi, Kyung Mook

    2013-05-01

    The epidemiological trends that characterize our generation are the aging of the population. Aging results in a progressive loss of muscle mass and strength called sarcopenia, which is Greek for 'poverty of flesh'. Sarcopenia could lead to functional impairment, physical disability, and even mortality. Today, sarcopenia is a matter of immense public concern for aging prevention. Its prevalence continues to rise, probably as a result of increasing elderly populations all over the world. This paper addressed the definition and epidemiology of sarcopenia and its underlying pathophysiology. In addition, we summarized the abundant information available in the literature related to sarcopenia, together with results from Korean sarcopenic obesity study (KSOS) that we performed.

  1. Epidemiology and the web of causation: has anyone seen the spider?

    PubMed

    Krieger, N

    1994-10-01

    'Multiple causation' is the canon of contemporary epidemiology, and its metaphor and model is the 'web of causation.' First articulated in a 1960 U.S. epidemiology textbook, the 'web' remains a widely accepted but poorly elaborated model, reflecting in part the contemporary stress on epidemiologic methods over epidemiologic theories of disease causation. This essay discusses the origins, features, and problems of the 'web,' including its hidden reliance upon the framework of biomedical individualism to guide the choice of factors incorporated in the 'web.' Posing the question of the whereabouts of the putative 'spider,' the author examines several contemporary approaches to epidemiologic theory, including those which stress biological evolution and adaptation and those which emphasize the social production of disease. To better integrate biologic and social understandings of current and changing population patterns of health and disease, the essay proposes an ecosocial framework for developing epidemiologic theory. Features of this alternative approach are discussed, a preliminary image is offered, and debate is encouraged.

  2. 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...

  3. 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.

  4. 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.

  5. 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.

  6. Applied field epidemiology programme in Spain.

    PubMed

    Martinez Navarro, J F; Herrera, D; Sanchez Barco, C

    2001-03-01

    In 1994, the Instituto de Salud Carlos III (ISCIII; Carlos III Health Institute) of the Spanish Ministry of Health and the Consumer (MSC) created the Programa de Epidemiología Aplicada de Campo (PEAC; Applied Field Epidemiology Programme). The programme is managed by the Centro Nacional de Epidemiología (National Epidemiological Centre) in collaboration with the Escuela Nacional de Sanidad (National School of Health), and supported by General Direction for Health and Consumer of MSC and the Health Councils (Consejerías de Sanidad) of the autonomous regions. The PEAC runs a masters degree programme in applied field epidemiology, in which degrees are conferred by the National School of Health. As PEAC is a national programme, it forms a part of the European Program for Intervention Epidemiology Training (EPIET) and is a member of the Network Training for Epidemiology Public Health Intervention (TEPHINET), the association of 27 regional and national programmes of the acting Intervention Epidemiology Training Programs.

  7. 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.

  8. Molecular epidemiology of glanders, Pakistan.

    PubMed

    Hornstra, Heidie; Pearson, Talima; Georgia, Shalamar; Liguori, Andrew; Dale, Julia; Price, Erin; O'Neill, Matthew; Deshazer, David; Muhammad, Ghulam; Saqib, Muhammad; Naureen, Abeera; Keim, Paul

    2009-12-01

    We collected epidemiologic and molecular data from Burkholderia mallei isolates from equines in Punjab, Pakistan from 1999 through 2007. We show that recent outbreaks are genetically distinct from available whole genome sequences and that these genotypes are persistent and ubiquitous in Punjab, probably due to human-mediated movement of equines.

  9. 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.

  10. Regression Discontinuity Designs in Epidemiology

    PubMed Central

    Moscoe, Ellen; Mutevedzi, Portia; Newell, Marie-Louise; Bärnighausen, Till

    2014-01-01

    When patients receive an intervention based on whether they score below or above some threshold value on a continuously measured random variable, the intervention will be randomly assigned for patients close to the threshold. The regression discontinuity design exploits this fact to estimate causal treatment effects. In spite of its recent proliferation in economics, the regression discontinuity design has not been widely adopted in epidemiology. We describe regression discontinuity, its implementation, and the assumptions required for causal inference. We show that regression discontinuity is generalizable to the survival and nonlinear models that are mainstays of epidemiologic analysis. We then present an application of regression discontinuity to the much-debated epidemiologic question of when to start HIV patients on antiretroviral therapy. Using data from a large South African cohort (2007–2011), we estimate the causal effect of early versus deferred treatment eligibility on mortality. Patients whose first CD4 count was just below the 200 cells/μL CD4 count threshold had a 35% lower hazard of death (hazard ratio = 0.65 [95% confidence interval = 0.45–0.94]) than patients presenting with CD4 counts just above the threshold. We close by discussing the strengths and limitations of regression discontinuity designs for epidemiology. PMID:25061922

  11. Epidemiology for the clinical neurologist.

    PubMed

    Jacob, M E; Ganguli, M

    2016-01-01

    Epidemiology is a foundation of all clinical and public health research and practice. Epidemiology serves seven important uses for the advancement of medicine and public health. It enables community diagnosis by quantifying risk factors and diseases in the community; completes the clinical picture of disease by revealing the entire distribution of disease and presenting meaningful population averages from representative samples; identifies risk factors for disease by detecting and quantifying associations between exposures and disease and evaluating causal hypotheses; computes individual risk to identify high-risk groups to whom preventive interventions can be targeted; evaluates historic trends that monitor disease over time and provide clues to etiology; delineates new syndromes and disease subtypes not previously apparent in clinical settings, helping to streamline effective disease management; and investigates the effects of health services on population health to identify effective public health interventions. The clinician with a grasp of epidemiologic principles is in a position to critically evaluate the research literature, to apply it to clinical practice, and to undertake valid clinical epidemiology research with patients in clinical settings. PMID:27637949

  12. Biostatistical applications in epidemiology.

    PubMed

    Kier, Karen L

    2011-01-01

    Understanding the application of statistical methods is an essential component in the process of evaluating the medical literature. Statistical methods can differ when evaluating randomized controlled clinical trials (experimental design) compared with observational study designs such as cohort or case-control. A review of common statistical concepts includes variables, measures of central tendency, and measures of dispersion. Other methods include sensitivity, specificity, and predictive value. Observational study designs often include relative risk, odds ratios, relative risk reduction, attributable risk, number needed to treat, and forest plots. A critical component of drug literature evaluation is the understanding of the proper use of parametric and nonparametric statistical tests. Common parametric tests and their nonparametric equivalents are discussed.

  13. 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

  14. 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 to examine…

  15. A Seven-Year Retrospective View of a Course in Epidemiology and Biostatistics.

    ERIC Educational Resources Information Center

    Mulvihill, Michael N.; And Others

    1980-01-01

    Modifications of a course in epidemiology and biostatistics, designed to facilitate the presentation of difficult material in a clinically relevant manner, are described. Key strategies include seminar sessions devoted to methods of epidemiology and the critique of pairs of published studies, and the use of a course-specific syllabus. (JMD)

  16. [Topical problems of sanitary and epidemiologic examination concerning projects of sanitary protection zones in airports].

    PubMed

    Isayeva, A M; Zibaryov, E V

    2015-01-01

    The article covers data on major errors in sanitary protection zones specification for civil airports, revealed through sanitary epidemiologic examination. The authors focus attention on necessity to develop unified methodic approach to evaluation of aviation noise effects, when justifying sanitary protection zone of airports and examining sanitary and epidemiologic project documents.

  17. Travel epidemiology: the Saudi perspective.

    PubMed

    Memish, Ziad A; Venkatesh, S; Ahmed, Qanta A

    2003-02-01

    The Kingdom of Saudi Arabia occupies four-fifths of the Arabian Peninsula, with a land area of 2 million square kilometres. Saudi Arabia holds a unique position in the Islamic world, as the custodian of the two holiest places of Islam, in Mecca and Medina. Annually, some 2 million Muslims from over 140 countries embark on Hajj. This extraordinary en masse migration is a unique forum for the study of travel epidemiology since the Hajj carries various health risks, both communicable and non-communicable, often on a colossal scale. Non-communicable hazards of the Hajj include stampede and motor vehicle trauma, fire-related burn injuries and accidental hand injury during animal slaughter. Communicable hazards in the form of outbreaks of multiple infectious diseases have been reported repeatedly, during and following the Hajj. Meningococcal meningitis, gastroenteritis, hepatitis A, B and C, and various zoonotic diseases comprise some of the possible infectious hazards at the Hajj. Many of these infectious and non-infectious hazards can be avoided or averted by adopting appropriate prophylactic measures. Physicians and health personnel must be aware of these risks to appropriately educate, immunize and prepare these travellers facing the unique epidemiological challenges of Hajj in an effort to minimize untoward effects. Travel epidemiology related to the Hajj is a new and exciting area, which offers valuable insights to the travel specialist. The sheer scale of numbers affords a rare view of migration medicine in action. As data is continually gathered and both national and international policy making is tailored to vital insights gained through travel epidemiology, the Hajj will be continually safeguarded. Practitioners will gain from findings of travel related epidemiological changes in evolution at the Hajj: the impact of vaccinating policies, infection control policies and public health are afforded a real-world laboratory setting at each annual Hajj, allowing us to

  18. 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…

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. Rethinking cumulative exposure in epidemiology, again.

    PubMed

    de Vocht, Frank; Burstyn, Igor; Sanguanchaiyakrit, Nuthchyawach

    2015-01-01

    The use of cumulative exposure, the product of intensity and duration, has enjoyed great popularity in epidemiology of chronic diseases despite numerous known caveats in its interpretation. We briefly review the history of use of cumulative exposure in epidemiology and propose an alternative method for relating time-integrated exposures to health risks. We argue, as others before us have, that cumulative exposure metrics obscures the interplay of exposure intensity and duration. We propose to use a computationally simple alternative in which duration and intensity of exposure are modelled as a main effect and their interaction, cumulative exposure, only be added if there is evidence of deviation from this additive model. We also consider the Lubin-Caporaso model of interplay of exposure intensity and duration. The impact of measurement error in intensity on model selection was also examined. The value of this conceptualization is demonstrated using a simulation study and further illustrated in the context of respiratory health and occupational exposure to latex dust. We demonstrate why cumulative exposure has been so popular because the cumulative exposure metric per se gives a robust answer to the existence of an association, regardless of the underlying true mechanism of disease. Treating cumulative exposure as the interaction of main effects of exposure duration and intensity enables epidemiologists to derive more information about mechanism of disease then fitting cumulative exposure metric by itself, and without the need to collect additional data. We propose that the practice of fitting duration, intensity and cumulative exposure separately to epidemiologic data should lead to conceptualization of cumulative exposure as interaction of main effects of duration and intensity of exposure. PMID:25138292

  6. 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

  7. 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

  8. Epidemiology and the identification of metals as human carcinogens.

    PubMed

    Duffus, J H

    1996-01-01

    Classification of substances as probable human carcinogens under the current IARC classification scheme is dependent on epidemiological evidence. The epidemiological data relating to the four metals currently identified as probable human carcinogens, in the metallic form or in the compounds, are reviewed and the weaknesses identified. These weaknesses lie mainly in exposure assessment. The weaknesses may be overcome to some extent by the use of metademographic methods as applied recently to the respiratory cancers that occurred at the Clydach Nickel Refinery in the first 30 years of this century. The general conclusion is that the epidemiological data relating to metals are unsatisfactory bases for the IARC classifications. There is a need to revise these classifications and to make them more precise by identifying exactly the substances which have caused human cancers. PMID:9122660

  9. 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.''

  10. 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…

  11. A ROAD MAP FOR EFFICIENT AND RELIABLE HUMAN GENOME EPIDEMIOLOGY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Network of investigators have begun sharing best practices, tools, and methods for analysis of associations between genetic variation and common diseases. A Network of Investigator Networks has been set up to drive the process, sponsored by the Human Genome Epidemiology Network. A workshop is planne...

  12. [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.

  13. [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.

  14. 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

  15. [Epidemiology of breast cancer].

    PubMed

    Rodríguez Cuevas, Sergio A; Capurso García, Marino

    2006-11-01

    Breast cancer is the most frequent malignant tumor worldwide. In recent years there has been observed an increase in its frequency, especially in developing countries, as Mexico, where mortality is arriving to the first cause of death in females. This is, in part, due to a delayed diagnosis, most frequently done in locally advances stages with a low cure rate. This is a review of all risk factors: age, sex, personal and familial history, genetic syndromes, associated breast disease, geographic distribution, body structure and environmental, hormonal, reproductive and dietary factors. It is concluded that breast cancer is a public health problem in developed and developing countries, and the best methods to drop mortality for breast cancer is the wide use of screening mammography in women at risk, in order to find cancers at initial stages and offer the adequate treatment.

  16. 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

  17. Epidemiology of psoriasis: clinical issues.

    PubMed

    Krueger, G G; Duvic, M

    1994-06-01

    Psoriasis is a genetically inherited spectrum of skin diseases characterized by epidermal proliferation and inflammation, which are reversible. Although many have reported that psoriasis is triggered by trauma, infections, stress, drugs, etc., the epidemiology of psoriasis remains poorly understood. Linkage to human leukocyte antigen-(HLA)-Cw6 and DR7 is strong in people with early onset disease, but concordance in monozygotic twins is only 67%, emphasizing the importance of a triggering event. Other factors that have been reported to affect the course of psoriasis include upper respiratory infections, smoking, obesity, alcohol ingestion, regional enteritis, and human immunodeficiency virus infection. This manuscript reviews the clinical epidemiology of psoriasis and highlights some of the needs for further investigation into specific areas of the disease.

  18. Epidemiology of cancer in Malaysia.

    PubMed

    Lo, E K

    1985-12-01

    Some information on cancer in Malaysia are available, and its epidemiology is described. There is a need for systematic and coordinated collection of cancer statistics which are essential to patient management, cancer control programme formulation, implementation and evaluation. The decision of the Ministry of Health to introduce National Cancer Registry and to encourage epidemiological studies, which will ultimately lead to the utilization of data and introduction of control and preventive activities for cancers are positive steps in the right direction. Meanwhile, curative and palliative treatment is available from the existing hospital facilities, and preventive activities such as actions on smoking and health will be continued until such time when a comprehensive prevention and control programme for cancers in the country is evolved.

  19. Landscape epidemiology of plant diseases.

    PubMed

    Plantegenest, Manuel; Le May, Christophe; Fabre, Frédéric

    2007-10-22

    Many agricultural landscapes are characterized by a high degree of heterogeneity and fragmentation. Landscape ecology focuses on the influence of habitat heterogeneity in space and time on ecological processes. Landscape epidemiology aims at applying concepts and approaches originating from landscape ecology to the study of pathogen dynamics at the landscape scale. However, despite the strong influence that the landscape properties may have on the spread of plant diseases, landscape epidemiology has still received little attention from plant pathologists. Some recent methodological and technological progress provides new and powerful tools to describe and analyse the spatial patterns of host-pathogen interactions. Here, we review some important topics in plant pathology that may benefit from a landscape perspective. These include the influence of: landscape composition on the global inoculum pressure; landscape heterogeneity on pathogen dynamics; landscape structure on pathogen dispersal; and landscape properties on the emergence of pathogens and on their evolution.

  20. 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

  1. Epidemiology of oral cancer in Arab countries

    PubMed Central

    Al-Jaber, Abeer; Al-Nasser, Lubna; El-Metwally, Ashraf

    2016-01-01

    Objectives: To review the oral cancer (OC) studies that were conducted in Arab countries with regard to epidemiology, risk factors, and prognosis. Methods: A computer-based PubMed literature search was performed to retrieve studies conducted in the Arab world on epidemiology of OC. After screening for exclusion criteria, cross-referencing, and searching local journals, a total of 19 articles were included. Results: Eight prevalence studies found an OC prevalence ranging from 1.8 to 2.13 per 100,000 persons. Oral cancer patients were mostly in their fifth to sixth decade of life, and the incidence in younger age was reported in some Arab countries. Yemenis have an alarming high prevalence of OC among people younger than 45 years. Eleven studies explored determinants or prognosis of OC. Behavioral determinants such as smokeless tobacco (Shamma and Qat), and cigarette smoking were strongly associated with OC. Alcohol drinking and solar radiation exposures were cited as possible risk factors. The most affected sites were tongue, floor of the mouth, and lower lip variations in the affected site were attributed to the socio-cultural behavior of the populations under study. Squamous cell carcinoma was the most frequently detected cancer, and usually patients were in late stages (III and IV) at the time of diagnosis. Conclusion: No solid evidence exists regarding the true OC prevalence/incidence in most Arab countries due to the lack of national cancer registries and population-based studies. PMID:26905345

  2. [Ordinary epidemiology: pleural mesothelioma and asbestos].

    PubMed

    Bonazzina, R; Azara, M; Gianera, A; Cannatelli, P; Zocchetti, C

    1997-01-01

    This paper describes a practical experience which took place in a Health District of the Lombardy Region (Northern Italy). This experience was motivated by the publication, on a newspaper, of the results of an epidemiological study which reported the nationwide geographical distribution of the mortality data for pleural mesothelioma during the period 1980-1987. The presence of excesses of pleural mesothelioma cases in two municipalities of Health District captured the attention of some field operators which decided to start working on the topic. Using all information available in the District all cases of pleural mesothelioma occurring during the period 1978-1993 in the two municipalities were identified; possible sources of both occupational and environmental asbestos exposure in the area were identified; and the next-of-kin of the cases was interviewed so as to gain information on the history of possible exposure to asbestos of the cases. For thirteen (out of seventeen) deaths the next-of-kin accepted to be interviewed and for them results are reported: the information presented describes gender, smoking habits, and an evaluation of the potential for exposure to asbestos both of occupational and environmental origin. We discuss the value importance of the experience, with particular emphasis on: a) the routine activities of the Services participating in the study; b) the resources employed; c) the use of epidemiological methods and tools; d) the primary prevention activities originated in the area; e) the personal motivations hat such experiences are capable to convey.

  3. Epidemiology of jumper's knee.

    PubMed

    Ferretti, A

    1986-01-01

    Jumper's knee is a typical functional overload injury because it affects those athletes who submit their knee extensor mechanisms to intense and repeated stress, e.g. volleyball and basketball players, high and long jumpers. According to the classification of Perugia and colleagues, it is an insertional tendinopathy affecting, in order of frequency, the insertion of the patellar tendon into the patella (65% of cases), attachment of the quadriceps tendon to the patella (25%) and the attachment of the patellar tendon to the tibial tuberosity (10%). The frequent occurrence of this injury in athletes led to the study of factors that may contribute to its onset and aggravation. These factors are divided into extrinsic (i.e. kind of sport practised and training methods used) and intrinsic (i.e. connected with the somatic and morphological characteristics of the athletes). On the basis of our experience and after a review of the literature it appears, contrary to what has been repeatedly claimed in the past, the extrinsic factors are more important than the intrinsic in the aetiology of jumper's knee. The effect of traumatic incidents and use of elastic kneecap guards should also be considered negligible. The intrinsic causes of jumper's knee, can be sought in the mechanical properties of tendons (resistance, elasticity and extensibility) rather than in morphological or biomechanical abnormalities of the knee extensor mechanism.

  4. Systematics and epidemiology of trichinella.

    PubMed

    Pozio, Edoardo; Darwin Murrell, K

    2006-01-01

    In this review, we describe the current knowledge on the systematics, ecology and epidemiology of Trichinella and trichinellosis, and the impact of recent research discoveries on the understanding of this zoonosis. The epidemiology of this zoonosis has experienced important changes over the past two decades, especially with regard to the importance of the sylvatic cycle and the sylvatic species. Outbreaks of trichinellosis due to Trichinella spiralis from domestic swine, while still frequent, increasingly are caused by other Trichinella spp. infecting hosts such as horses, dogs, wild boars, bears and walruses. The latter revelations have occurred as a result of a series of discoveries on the systematics of Trichinella spp., facilitated by new molecular tools. As a consequence, the genus is now composed of two clades, an encapsulated group (five species and three genotypes) and a non-encapsulated one (three species). This has sparked renewed investigations on the host range of these parasites and their epidemiological features. Most dramatic, perhaps, is the recognition that reptiles may also serve as hosts for certain species. This new knowledge base, in addition to having an important relevance for food safety policies and protection measures, is raising important questions on the phylogeny of Trichinella spp., the ecological characteristics of the species and their geographic histories. Answers to these questions may have great value for the understanding of the evolutionary biology for other parasitic helminths, and may increase the value of this genus as models for research on parasitism in general. PMID:17134656

  5. Biomarkers in Prostate Cancer Epidemiology

    PubMed Central

    Verma, Mukesh; Patel, Payal; Verma, Mudit

    2011-01-01

    Understanding the etiology of a disease such as prostate cancer may help in identifying populations at high risk, timely intervention of the disease, and proper treatment. Biomarkers, along with exposure history and clinical data, are useful tools to achieve these goals. Individual risk and population incidence of prostate cancer result from the intervention of genetic susceptibility and exposure. Biochemical, epigenetic, genetic, and imaging biomarkers are used to identify people at high risk for developing prostate cancer. In cancer epidemiology, epigenetic biomarkers offer advantages over other types of biomarkers because they are expressed against a person's genetic background and environmental exposure, and because abnormal events occur early in cancer development, which includes several epigenetic alterations in cancer cells. This article describes different biomarkers that have potential use in studying the epidemiology of prostate cancer. We also discuss the characteristics of an ideal biomarker for prostate cancer, and technologies utilized for biomarker assays. Among epigenetic biomarkers, most reports indicate GSTP1 hypermethylation as the diagnostic marker for prostate cancer; however, NKX2-5, CLSTN1, SPOCK2, SLC16A12, DPYS, and NSE1 also have been reported to be regulated by methylation mechanisms in prostate cancer. Current challenges in utilization of biomarkers in prostate cancer diagnosis and epidemiologic studies and potential solutions also are discussed. PMID:24213111

  6. Epidemiological studies in psychosomatic medicine.

    PubMed

    Eastwood, M R

    1975-01-01

    The epidemiological triad of host, agent and environment used conceptually in infectious disease may serve as a model for psychosomatic disorders, despite the involvement of many more variables. There are major problems with diagnosis and measurement, however, and the term "psychosomatic" has several meanings. The two main senses are "specific" psychosomatic disorders and an ecological view of illness. The association between psychiatric and physical disorder has been examined in a variety of settings and the findings have suggested that there is a positive relationship. Despite considerable methodological and sampling difficulties in epidemiological research into psychosomatic illness, recent efforts have been made to overcome these. The results of ecological studies appear to be more consistent that those dealing with "specific" psychosomatic disorders and suggest that man has a general psychophysical propensity to disease. Although physical and mental illness do seem to be intimately linked, the reasons for "vulnerability" to illness and "clustering" of illness are obscure. The clarification of these areas appears to be the main task ahead for epidemiology in the field of psychosomatic medicine. PMID:773850

  7. Epidemiology of uterine cervical cancer.

    PubMed

    Brinton, L A; Fraumeni, J F

    1986-01-01

    The epidemiology of cervical cancer presents a number of unique challenges, mainly with respect to disentangling correlated factors and to elucidating biological mechanisms. The available evidence suggests a complex multifactorial etiology, although the relative contributions of risk factors and their interactions remain obscure. Infectious agents are strongly suspected, but as yet not conclusively identified. It is also unclear whether there are subgroups of women or periods of life that are most susceptible to the action of infectious agents, and the contribution of the "male factor" needs to be defined. Several epidemiologic leads can be pursued through biochemical and molecular techniques. Most promising is the recent evidence linking certain HPV types to cervical abnormalities, including cancer, and newly developed probes can be incorporated into epidemiologic studies to evaluate an array of risk factors. Endocrine and metabolic assays may be helpful in clarifying the role of exogenous and possibly endogenous hormones. The effects of cigarette smoking may be further evaluated by studying constituents of tobacco smoke and their metabolites in cervical mucus. Finally, the relationship of diet to cervical cancer should be assessed by examining the levels of micronutrients, trace minerals, and other nutritional indices in body tissues and fluids, as well as through interview data. An understanding of cervical cancer etiology will require a better identification of risk factors for precursor lesions as well as factors that enhance their progression to invasive cancer. Through studies that focus on disease stage and time-related events, it should be possible to clarify the multi-stage processes involved in cervical carcinogenesis, and those factors that may inhibit as well as promote transition rates. The protective effects of screening programs deserve further attention, and research into dietary factors may lead in time to nutritional intervention. Investigation

  8. 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 Central

    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 3rd 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. PMID:26523191

  9. 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.

  10. Aluminium and Alzheimer's disease: An epidemiological approach.

    PubMed

    Martyn, C N

    1990-03-01

    Epidemiological methods have an important role in the investigation of the postulated connection between exposure to aluminium and the development of Alzheimer's disease. We have examined the usefulness of existing data on prevalence and mortality as a resource for studying variations in the rate of the disease with time and geography. Unfortunately, methodological differences between prevalence surveys and errors and biases in mortality data are large. No reliable conclusions can be drawn from these data about geographical differences in rates of dementia in England and Wales nor about time trends in the disease.Aluminium salts are widely used in the UK for the treatment of drinking water. Residual aluminium concentrations vary more than ten fold between different parts of the country. We have estimated diagnostic rates of pre-senile Alzheimer's disease in seven geographical areas and examined the correlation between rates of Alzheimer's disease and water aluminium concentration. PMID:24202582

  11. Applying Evolutionary Genetics to Schistosome Epidemiology

    PubMed Central

    Steinauer, Michelle L.; Blouin, Michael S.; Criscione, Charles D.

    2010-01-01

    We review how molecular markers and evolutionary analysis have been applied to the study of schistosome parasites, important pathogens that infect over 200 million people worldwide. Topics reviewed include phylogenetics and biogeography, hybridization, infection within snails, mating systems, and genetic structure. Some interesting generalizations include that schistosome species hybridize frequently and have switched definitive hosts repeatedly in evolutionary time. We show that molecular markers can be used to infer epidemiologically-relevant processes such as spatial variation in transmission, or to reveal complex patterns of mate choice. Analysis of genetic structure data shows that transmission foci can be structured by watershed boundaries, habitat types, and host species. We also discuss sampling and analytical problems that arise when using larvae to estimate genetic parameters of adult schistosome populations. Finally, we review pitfalls in methodologies such as genotyping very small individuals, statistical methods for identifying clonemates or for identifying sibling groups, and estimating allele frequencies from pooled egg samples. PMID:20176142

  12. 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

  13. 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.

  14. Epidemiology.

    PubMed

    Walsh, Kyle M; Ohgaki, Hiroko; Wrensch, Margaret R

    2016-01-01

    More than 250,000 new cases of primary malignant brain tumors are diagnosed annually worldwide, 77% of which are gliomas. A small proportion of gliomas are caused by the inheritance of rare high-penetrance genetic variants or high-dose radiation. Since 2009, inherited genetic variants in 10 regions near eight different genes have been consistently associated with glioma risk via genome-wide association studies. Most of these variants increase glioma risk by 20-40%, but two have higher relative risks. One on chromosome 8 increases risk of IDH-mutated gliomas sixfold and another that affects TP53 function confers a 2.5-fold increased risk of glioma. Functions of some of the other risk variants are known or suspected, but future research will determine functions of other risk loci. Recent progress also has been made in defining subgroups of glioma based on acquired alterations within tumors. Allergy history has been consistently associated with reduced glioma risk, though the mechanisms have not yet been clarified. Future studies will need to be large enough so that environmental and constitutive genetic risk factors can be examined within molecularly defined, etiologically homogeneous subgroups.

  15. Lethal mutagenesis and evolutionary epidemiology.

    PubMed

    Martin, Guillaume; Gandon, Sylvain

    2010-06-27

    The lethal mutagenesis hypothesis states that within-host populations of pathogens can be driven to extinction when the load of deleterious mutations is artificially increased with a mutagen, and becomes too high for the population to be maintained. Although chemical mutagens have been shown to lead to important reductions in viral titres for a wide variety of RNA viruses, the theoretical underpinnings of this process are still not clearly established. A few recent models sought to describe lethal mutagenesis but they often relied on restrictive assumptions. We extend this earlier work in two novel directions. First, we derive the dynamics of the genetic load in a multivariate Gaussian fitness landscape akin to classical quantitative genetics models. This fitness landscape yields a continuous distribution of mutation effects on fitness, ranging from deleterious to beneficial (i.e. compensatory) mutations. We also include an additional class of lethal mutations. Second, we couple this evolutionary model with an epidemiological model accounting for the within-host dynamics of the pathogen. We derive the epidemiological and evolutionary equilibrium of the system. At this equilibrium, the density of the pathogen is expected to decrease linearly with the genomic mutation rate U. We also provide a simple expression for the critical mutation rate leading to extinction. Stochastic simulations show that these predictions are accurate for a broad range of parameter values. As they depend on a small set of measurable epidemiological and evolutionary parameters, we used available information on several viruses to make quantitative and testable predictions on critical mutation rates. In the light of this model, we discuss the feasibility of lethal mutagenesis as an efficient therapeutic strategy.

  16. [Workshop on Molecular Epidemiology of Viral Diseases].

    PubMed

    Gómez, B; Cabrera, L; Arias, C F

    1997-01-01

    A workshop on viral epidemiology was held on September 29, 1995 at the Medical School of the Universidad Nacional Autónoma de Mexico. The aim of this workshop was to promote interaction among scientists working in viral epidemiology. Eighteen scientists from ten institutions presented their experiences and work. General aspects of the epidemiology of meaningful viral diseases in the country were discussed, and lectures presented on the rota, polio, respiratory syncytial, dengue, papiloma, rabies, VIH and hepatitis viruses.

  17. [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.

  18. 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.

  19. Epidemiology: past, present and future.

    PubMed

    Kesteloot, H

    2004-01-01

    Epidemiology in the past was concerned essentially by the study of infectious diseases which were the cause of huge mortalities especially since urbanisation was initiated. Epidemics of pest, typhus, cholera, influenza a.o. were common. The epidemics were halted by better hygiene, vaccination and antibiotics. Since the second world war epidemiology was dominated by an "epidemic" of new chronic diseases, especially heart disease and cancer. This was due to an increase in life span and to an increase in smoking habits and in the intake of saturated fat and a too small intake of fruit and vegetables combined with a too high intake of salt (NaCl). Gradually epidemiology evolved as the study of the causes, the distribution, the risk factors and the prevention of chronic diseases, but also including accidents, suicide, depression a.o., diseases with a mass occurrence at the population level. The importance of nutrition as a determinant of health gradually became recognized, but remains undervalued by the medical profession. Mortality at the population level follows some simple mathematical laws and can be represented accurately (r2>0.99) between the ages of 35 and 84 year by either Gompertz equations (ln mortality versus age) or by a polynomial equation (ln mortality versus age, age2). This is valid for all populations and both sexes and remains valid at times of great and rapid changes in mortality. This shows that measures for prevention should be directed towards the total population. The future of epidemiology should be directed towards the slowing of the ageing process at the population level by a healthy life style consisting of: not smoking, avoiding obesity, a fair amount of physical activity and a healthy nutrition i.e little salt, little saturated fat, an adequate amount of omega-3 fatty acids and a large amount of fruit and vegetables, with an occasional glass of red wine. This contains the secret of a long and healthy life. Conceptually it will be important

  20. 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.

  1. 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

  2. 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.

  3. Measles - The epidemiology of elimination.

    PubMed

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

    2014-12-01

    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. PMID:25444814

  4. The landscape epidemiology of echinococcoses.

    PubMed

    Cadavid Restrepo, Angela M; Yang, Yu Rong; McManus, Donald P; Gray, Darren J; Giraudoux, Patrick; Barnes, Tamsin S; Williams, Gail M; Soares Magalhães, Ricardo J; Hamm, Nicholas A S; Clements, Archie C A

    2016-01-01

    Echinococcoses are parasitic diseases of major public health importance globally. Human infection results in chronic disease with poor prognosis and serious medical, social and economic consequences for vulnerable populations. According to recent estimates, the geographical distribution of Echinococcus spp. infections is expanding and becoming an emerging and re-emerging problem in several regions of the world. Echinococcosis endemicity is geographically heterogeneous and over time it may be affected by global environmental change. Therefore, landscape epidemiology offers a unique opportunity to quantify and predict the ecological risk of infection at multiple spatial and temporal scales. Here, we review the most relevant environmental sources of spatial variation in human echinococcosis risk, and describe the potential applications of landscape epidemiological studies to characterise the current patterns of parasite transmission across natural and human-altered landscapes. We advocate future work promoting the use of this approach as a support tool for decision-making that facilitates the design, implementation and monitoring of spatially targeted interventions to reduce the burden of human echinococcoses in disease-endemic areas. PMID:26895758

  5. Molecular epidemiology of cystic echinococcosis.

    PubMed

    McManus, D P; Thompson, R C A

    2003-01-01

    Echinococcus granulosus exhibits substantial genetic diversity that has important implications for the design and development of vaccines, diagnostic reagents and drugs effective against this parasite. DNA approaches that have been used for accurate identification of these genetic variants are presented here as is a description of their application in molecular epidemiological surveys of cystic echinococcosis in different geographical settings and host assemblages. The recent publication of the complete sequences of the mitochondrial (mt) genomes of the horse and sheep strains of E. granulosus and of E. multilocularis, and the availability of mt DNA sequences for a number of other E. granulosus genotypes, has provided additional genetic information that can be used for more in depth strain characterization and taxonomic studies of these parasites. This very rich sequence information has provided a solid molecular basis, along with a range of different biological, epidemiological, biochemical and other molecular-genetic criteria, for revising the taxonomy of the genus Echinococcus. This has been a controversial issue for some time. Furthermore, the accumulating genetic data may allow insight to several other unresolved questions such as confirming the occurrence and precise nature of the E. granulosus G9 genotype and its reservoir in Poland, whether it is present elsewhere, why the camel strain (G6 genotype) appears to affect humans in certain geographical areas but not others, more precise delineation of the host and geographic ranges of the genotypes characterised to date, and whether additional genotypes of E. granulosus remain to be identified. PMID:15042999

  6. Epidemiology and Genetics of Hypertension.

    PubMed

    Sarkar, Taposh; Singh, Narinder Pal

    2015-09-01

    The prevalence of hypertension is increasing in India as well as in the world. The average prevalence of hypertension in India is 25-30%. The median prevalence of total hypertension in 2009 was 37.6% in men and 40.1% in women in U.S. Hypertension is a major risk factor for majority of patients with cardiovascular, cerebrovascular and renal morbidity and mortality. Environmental factors as well as genetic factors account for regulation of blood pressure and its control. Understanding of genetic factor may not only help in recognising those at risk but also help in treatment. Discovering hypertension susceptibility genes would help recognizing those at risk for developing the disease before the expression of clinical symptoms. Genetic and epidemiological studies have suggested that essential hypertension is a polygenic and multifactorial disorder that results from genetic and/or environmental factors. In India awareness, treatment and control status of hypertension is low, with only half of the urban and a quarter of the rural hypertensive individuals being aware of its presence. In this review we have discussed epidemiology and genetics of hypertension, both the monogenic and polygenic forms. PMID:27608868

  7. [Epidemiology of acromegaly in Spain].

    PubMed

    Sesmilo, Gemma

    2013-10-01

    Epidemiology of acromegaly in Spain does not differ from that reported in other published series. Prevalence rate is approximately 60 cases per million, peak incidence occurs in middle age, more women are affected (61%), and there is a substantial delay between occurrence of the first symptoms and diagnosis. Studies REA (Spanish Acromegaly Registry) and OASIS analyzed the epidemiology, clinical characteristics, and management of the disease in Spain. Surgery, performed in more than 80% of patients, has been (and continues to be) the main treatment for the past four decades. In the past decade, however, more patients have received somatostatin analogs (SSAs) as first-line treatment. Use of radiation therapy has significantly decreased in recent decades. Somatostatin analogs (SSAs) are the most commonly used drugs, administered to 85% of patients; however, only 12%-15% continue on drug treatment alone. The surgical remission rate was 38.4% in the last decade, with a significant improvement over decades. Preoperative treatment with SSAs has no influence on surgical cure rates. Second-line therapies used after surgical failure in the past decade included SSAs in 49% of patients, repeat surgery in 27%, radiotherapy in 11%, pegvisomant in 15%, and dopamine agonists in 5%. Mean cost of acromegaly treatment was 9.668€ (data estimated in 2009 and adjusted in 2010), of which 71% was due to the cost of SSAs. Patients treated with pegvisomant have a more aggressive form of the disease and higher comorbidity rates.

  8. Epidemiology of yaws: an update

    PubMed Central

    Kazadi, Walter M; Asiedu, Kingsley B; Agana, Nsiire; Mitjà, Oriol

    2014-01-01

    Yaws, a neglected tropical disease, is targeted for eradication by 2020 through large-scale mass-treatment programs of endemic communities. A key determinant for the success of the eradication campaign is good understanding of the disease epidemiology. We did a review of historical trends and new information from endemic countries, with the aim of assessing the state of knowledge on yaws disease burden. Transmission of yaws is now present in Africa, Asia, and the South Pacific. At least 12 countries are known to harbor yaws cases and 21 to 42 million people live in endemic areas. Between 2008 and 2012 more than 300,000 new cases were reported to the World Health Organization. Yaws presented high geographical variation within a country or region, high seasonality for incidence of active disease, and evidence that low standards of hygiene predispose to suffering of the disease. Key data issues include low levels of reporting, potential misdiagnosis, and scarce documentation on prevalence of asymptomatic infections. Currently available data most likely underestimates the magnitude of the disease burden. More effort is needed in order to refine accuracy of data currently being reported. A better characterization of the epidemiology of yaws globally is likely to positively impact on planning and implementation of yaws eradication. PMID:24729728

  9. 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

  10. 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.

  11. Measles - The epidemiology of elimination.

    PubMed

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

    2014-12-01

    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.

  12. 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

  13. The CONSTANCES cohort: an open epidemiological laboratory

    PubMed Central

    2010-01-01

    Background Prospective cohorts represent an essential design for epidemiological studies and allow for the study of the combined effects of lifestyle, environment, genetic predisposition, and other risk factors on a large variety of disease endpoints. The CONSTANCES cohort is intended to provide public health information and to serve as an "open epidemiologic laboratory" accessible to the epidemiologic research community. Although designed as a "general-purpose" cohort with very broad coverage, it will particularly focus on occupational and social determinants of health, and on aging. Methods/Design The CONSTANCES cohort is designed as a randomly selected representative sample of French adults aged 18-69 years at inception; 200,000 subjects will be included over a five-year period. At inclusion, the selected subjects will be invited to fill a questionnaire and to attend a Health Screening Center (HSC) for a comprehensive health examination: weight, height, blood pressure, electrocardiogram, vision, auditory, spirometry, and biological parameters; for those aged 45 years and older, a specific work-up of functional, physical, and cognitive capacities will be performed. A biobank will be set up. The follow-up includes a yearly self-administered questionnaire, and a periodic visit to an HSC. Social and work-related events and health data will be collected from the French national retirement, health and death databases. The data that will be collected include social and demographic characteristics, socioeconomic status, life events, behaviors, and occupational factors. The health data will cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalizations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare utilization and services provided, and causes of death. To take into account non-participation at inclusion and attrition throughout the longitudinal follow-up, a cohort

  14. 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

  15. 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

  16. 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

  17. [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.

  18. 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...

  19. [Epidemiology of age-related macular degeneration].

    PubMed

    Brandl, C; Stark, K J; Wintergerst, M; Heinemann, M; Heid, I M; Finger, R P

    2016-09-01

    Age-related macular degeneration (AMD) is the main cause of blindness in industrialized societies. Population-based epidemiological investigations generate important data on prevalence, incidence, risk factors, and future trends. This review summarizes the most important epidemiological studies on AMD with a focus on their transferability to Germany including existing evidence for the main risk factors for AMD development and progression. Future tasks, such as the standardization of grading systems and the use of recent retinal imaging technology in epidemiological studies are discussed. In Germany, epidemiological data on AMD are scarce. However, the need for epidemiological research in ophthalmology is currently being addressed by several recently started population-based studies. PMID:27541733

  20. 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. PMID:17827097

  1. Improving estimates of exposures for epidemiologic studies of plutonium workers.

    PubMed

    Ruttenber, A J; Schonbeck, M; McCrea, J; McClure, D; Martyny, J

    2001-01-01

    Epidemiologic studies of nuclear facilities usually focus on relations between cancer and doses from external penetrating radiation, and describe these exposures with little detail on measurement error and missing data. We demonstrate ways to document complex exposures to nuclear workers with data on external and internal exposures to ionizing radiation and toxic chemicals. We describe methods for assessing internal exposures to plutonium and external doses from neutrons; the use of a job exposure matrix for estimating chemical exposures; and methods for imputing missing data for exposures and doses. For plutonium workers at Rocky Flats, errors in estimating neutron doses resulted in underestimating the total external dose for production workers by about 16%. Estimates of systemic deposition do not correlate well with estimates of organ doses. Only a small percentage of workers had exposures to toxic chemicals, making epidemiologic assessments of risk difficult. PMID:11319050

  2. Paper vs. electrons. Epidemiologic publishing in a changing world.

    PubMed

    Rothenberg; Frank; Fitzmaurice

    2000-10-01

    PURPOSE: To present the parallel histories of epidemiologic and electronic publishing and consider positive and negative factors that might affect their amalgam.METHODS: We performed a quantitative assessment of the arc of epidemiologic publication from 1966-1999, using major self-designated epidemiologic journals as a sample, and of scholarly electronic publication from 1991-1997, based on current literature review. We use an online, paperless journal as a case study, and review selected information-technology opinion in the area.RESULTS: By traditional standards, growth in epidemiologic publication has been considerable, with the addition of six new journals since 1966. In contrast, scholarly electronic publication for the period 1991-1997 grew from 27 to 2459 journals (not all exclusively online). Positive features of electronic publishing include flexibility, shortened time to publication, freedom from fixed publication date, diversity in presentation, and instant linkage to relevant material. A case study of a new online journal illustrates the substantive power of the medium. Negative factors include restriction (or unrestricted expansion) of the audience, the potential for hasty peer review, pitfalls in establishing credibility, an emphasis on style over content, technologic dependence, and additions to the information explosion. Relative cost and archiving are still debated. In assessing the pros and cons, it is important to distinguish electronic mechanisms that facilitate publication from electronic publishing, and to appreciate the difference between moving an existing journal to the electronic medium, and creating a new online journal.CONCLUSIONS: The movement from print to internet is probably inexorable, but a headlong rush may be ill-advised. Several models for dual publishing now exist, with the expectation that many, including the journals that serve epidemiology, will do so. The ultimate configuration is difficult to predict, but likely to be

  3. Epidemiological studies of oral cancer.

    PubMed

    Pindborg, J J

    1977-06-01

    The FDI has shown considerable interest in the oral cancer and has in recent years arranged three symposia on the subject. The incidence of oral cancer shows marked geographic differences mostly depending upon environmental factors. In the present paper the epidemiology of oral cancer is illustrated by the relative frequency to total number of cancers and incidence rates from a number of countries. Canada has the highest rate of cancer of the vermilion border, which is extremely rare among dark-skinned people. Even within one country differences may be found, a fact which is illustrated by findings from Czechoslovakia and India. In most of the studies dealing with the etiology of oral cancer tobacco usage in its various forms is shown to be the outstanding factor.

  4. 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

  5. Social Network Visualization in Epidemiology

    PubMed Central

    Christakis, Nicholas A.; Fowler, James H.

    2010-01-01

    Epidemiological investigations and interventions are increasingly focusing on social networks. Two aspects of social networks are relevant in this regard: the structure of networks and the function of networks. A better understanding of the processes that determine how networks form and how they operate with respect to the spread of behavior holds promise for improving public health. Visualizing social networks is a key to both research and interventions. Network images supplement statistical analyses and allow the identification of groups of people for targeting, the identification of central and peripheral individuals, and the clarification of the macro-structure of the network in a way that should affect public health interventions. People are inter-connected and so their health is inter-connected. Inter-personal health effects in social networks provide a new foundation for public health. PMID:22544996

  6. 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.

  7. 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

  8. The epidemiology of ovarian cancer.

    PubMed

    Tortolero-Luna, G; Mitchell, M F

    1995-01-01

    Ovarian cancer is the second most common cancer of the female reproductive system and the leading cause of death from gynecologic malignancies. In 1995, 26,600 women will be diagnosed with ovarian cancer in the U.S., and 14,500 women will die from the disease. Between 1986-1900, the overall age-adjusted incidence was 14.3/100,000 women; mortality was 7.8/100,000 women. Ovarian cancer, rare before age 40, increases steeply thereafter and peaks at ages 65-75. Incidence and mortality rates are higher among white women than among African-American women. Over the last three decades, ovarian cancer incidence has remained stable in high-risk countries, while an increasing trend has been reported in low-risk countries. Despite recent advancements in treatment, the overall five-year survival rates continues to be low (39%). Over 70% of ovarian tumors are diagnosed when regional or distant involvement has already occurred, causing survival rates to remain stable. The etiology of ovarian cancer is poorly understood. Most studies have focused on the epidemiology of invasive epithelial ovarian tumors, while few have explored the epidemiology of epithelial tumors of low malignant potential and nonepithelial tumors. Factors associated with an increased risk for invasive epithelial ovarian cancer include age, race, nulliparity, family history of ovarian cancer, and history of endometrial or breast cancer. Factors associated with a reduced risk are history of one or more full-term pregnancies, use of oral contraceptives, history of breast feeding, tubal ligation, and hysterectomy. Other factors such as infertility drugs, hormone replacement therapy, age at menarche, age at menopause, dietary factors, lactose intolerance, talc use, coffee and alcohol consumption have been suggested, but their role is still inconclusive.

  9. On the epidemiology of influenza

    PubMed Central

    Cannell, John J; Zasloff, Michael; Garland, Cedric F; Scragg, Robert; Giovannucci, Edward

    2008-01-01

    The epidemiology of influenza swarms with incongruities, incongruities exhaustively detailed by the late British epidemiologist, Edgar Hope-Simpson. He was the first to propose a parsimonious theory explaining why influenza is, as Gregg said, "seemingly unmindful of traditional infectious disease behavioral patterns." Recent discoveries indicate vitamin D upregulates the endogenous antibiotics of innate immunity and suggest that the incongruities explored by Hope-Simpson may be secondary to the epidemiology of vitamin D deficiency. We identify – and attempt to explain – nine influenza conundrums: (1) Why is influenza both seasonal and ubiquitous and where is the virus between epidemics? (2) Why are the epidemics so explosive? (3) Why do they end so abruptly? (4) What explains the frequent coincidental timing of epidemics in countries of similar latitude? (5) Why is the serial interval obscure? (6) Why is the secondary attack rate so low? (7) Why did epidemics in previous ages spread so rapidly, despite the lack of modern transport? (8) Why does experimental inoculation of seronegative humans fail to cause illness in all the volunteers? (9) Why has influenza mortality of the aged not declined as their vaccination rates increased? We review recent discoveries about vitamin D's effects on innate immunity, human studies attempting sick-to-well transmission, naturalistic reports of human transmission, studies of serial interval, secondary attack rates, and relevant animal studies. We hypothesize that two factors explain the nine conundrums: vitamin D's seasonal and population effects on innate immunity, and the presence of a subpopulation of "good infectors." If true, our revision of Edgar Hope-Simpson's theory has profound implications for the prevention of influenza. PMID:18298852

  10. [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.

  11. A "big data" approach to HIV epidemiology and prevention.

    PubMed

    Young, Sean D

    2015-01-01

    The recent availability of "big data" from social media and mobile technologies provides promise for development of new tools and methods to address the HIV epidemic. This manuscript presents recent work in this growing area of bioinformatics, digital epidemiology, and disease modeling, describes how it can be applied to address HIV prevention, and presents issues that need to be addressed prior to implementing a mobile technology big-data approach to HIV prevention. PMID:25449693

  12. GESDB: a platform of simulation resources for genetic epidemiology studies.

    PubMed

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.twDatabase URL: http://gesdb.nhri.org.tw. PMID:27242038

  13. GESDB: a platform of simulation resources for genetic epidemiology studies.

    PubMed

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.twDatabase URL: http://gesdb.nhri.org.tw.

  14. GESDB: a platform of simulation resources for genetic epidemiology studies

    PubMed Central

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.tw. Database URL: http://gesdb.nhri.org.tw PMID:27242038

  15. Epidemiology's Continuing Contribution to Public Health: The Power of “Then and Now”

    PubMed Central

    Buck Louis, Germaine M.; Bloom, Michael S.; Gatto, Nicolle M.; Hogue, Carol R.; Westreich, Daniel J.; Zhang, Cuilin

    2015-01-01

    The 47th annual meeting of the Society for Epidemiologic Research hosted 17 invited speakers charged by the Executive Committee with presenting some of the many ways that epidemiologists have improved the health of the general population. There were 9 “Then and Now” sessions that were structured to focus on how early epidemiologists overcame research hurdles and advanced health through innovative strategies. For most topics, a longstanding expert was paired with an excellent contemporary epidemiologist working in the area, and both were given the freedom to deliver an integrated story about epidemiology's temporal role in protecting and promoting public health. Epidemiologic discoveries in cardiovascular, cancer, and perinatal epidemiology were discussed on day 1, followed by discussions of accomplishments in reducing exposures that adversely impact health (nutrition, environment/occupation, and tobacco use) on day 2. Topics with relevancy for many aspects of epidemiology were presented on day 3, including infectious diseases, social forces, and causal thinking in epidemiologic research. Given the large number of outstanding senior and junior epidemiologists that attended the meeting, choosing speakers was a unique challenge. What became evident from all sessions was the passion that epidemiologists have for population health, tempered with concerns for remaining true to epidemiologic principles, the timely adoption of innovative methods, and the responsible interpretation of research findings. PMID:25810458

  16. 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

  17. 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

  18. 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

  19. 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

  20. Molecular epidemiology of human intestinal amoebas in iran.

    PubMed

    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.

  1. 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

  2. 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

  3. A growing role for gender analysis in air pollution epidemiology.

    PubMed

    Clougherty, Jane E

    2011-04-01

    Epidemiologic studies of air pollution effects on respiratory health report significant modification by sex, although results are not uniform. Importantly, it remains unclear whether modifications are attributable to socially derived gendered exposures, to sex-linked physiological differences, or to some interplay thereof. Gender analysis, which aims to disaggregate social from biological differences between males and females, may help to elucidate these possible sources of effect modification. Studies of children suggest stronger effects among boys in early life and among girls in later childhood. The qualitative review describes possible sources of difference in air pollution response between women and men, which may vary by life stage, coexposures, hormonal status, or other factors. The sources of observed effect modifications remain unclear, although gender analytic approaches may help to disentangle gender and sex differences in pollution response. A framework for incorporating gender analysis into environmental epidemiology is offered, along with several potentially useful methods from gender analysis. PMID:21584463

  4. Sampling in epidemiological research: issues, hazards and pitfalls

    PubMed Central

    Tyrer, Stephen; Heyman, Bob

    2016-01-01

    Surveys of people's opinions are fraught with difficulties. It is easier to obtain information from those who respond to text messages or to emails than to attempt to obtain a representative sample. Samples of the population that are selected non-randomly in this way are termed convenience samples as they are easy to recruit. This introduces a sampling bias. Such non-probability samples have merit in many situations, but an epidemiological enquiry is of little value unless a random sample is obtained. If a sufficient number of those selected actually complete a survey, the results are likely to be representative of the population. This editorial describes probability and non-probability sampling methods and illustrates the difficulties and suggested solutions in performing accurate epidemiological research. PMID:27087985

  5. Sampling in epidemiological research: issues, hazards and pitfalls.

    PubMed

    Tyrer, Stephen; Heyman, Bob

    2016-04-01

    Surveys of people's opinions are fraught with difficulties. It is easier to obtain information from those who respond to text messages or to emails than to attempt to obtain a representative sample. Samples of the population that are selected non-randomly in this way are termed convenience samples as they are easy to recruit. This introduces a sampling bias. Such non-probability samples have merit in many situations, but an epidemiological enquiry is of little value unless a random sample is obtained. If a sufficient number of those selected actually complete a survey, the results are likely to be representative of the population. This editorial describes probability and non-probability sampling methods and illustrates the difficulties and suggested solutions in performing accurate epidemiological research.

  6. 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

  7. [Current status of dengue virus infections. Epidemiologic and pathogenetic aspects].

    PubMed

    Tolou, H; Baudon, D; Laroche, R

    1997-01-01

    The epidemiology of dengue fever is changing dramatically. The worldwide incidence is rising and clinical symptoms are worsening. Reports describing forms associated with hemorrhage or shock syndrome involving both children and adults are increasingly frequent in regions beyond Southeast Asia where the first cases were observed. Many mechanisms could be implicated in these changes including modifications of the virus, host, vector, or socioeconomic factors. Since no current model allows laboratory analysis of these mechanisms, observation of epidemics is still a major source of data. The findings of well conducted epidemiological studies allow not only assessment of morbidity and mortality in endemic areas and early detection of epidemic outbreaks but also evaluation of socioeconomic impact and effectiveness of control measures. Surveillance techniques must be chosen in function of prevailing local conditions. To ensure reliable results studies should be carried out in collaboration with an international network and a simple and accurate method of disease identification should be used.

  8. 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

  9. Epidemiology of Attention Problems Among Turkish Children and Adolescents

    PubMed Central

    Erol, Nese; Simsek, Zeynep; Öner, Özgür; Munir, Kerim

    2011-01-01

    Objective To evaluate the epidemiology of attention problems using parent, teacher, and youth informants among a nationally representative Turkish sample. Method The children and adolescents, 4 to 18 years old, were selected from a random household survey. Attention problems derived from the Child Behavior Checklist (CBCL) (N = 4,488), Teacher Report Form (TRF) (N = 2,360), and the Youth Self Report (YSR) (N = 2,206) were examined. Results The CBCL and TRF attention problems scores were higher among young male children, whereas the YSR reported scores were higher among older adolescents without a gender effect. The CBCL and YSR scores were also higher by urban residence. Conclusion Compared with other European samples, our national sample had higher mean attention problems scores than the Scandinavian but lower mean scores than the former Soviet Union samples. In addition to elucidating the profile of attention problems in Turkey, our results also contribute to understanding the comparative global epidemiology of attention problems. PMID:18192617

  10. Childhood accidents. Three epidemiological studies on the etiology.

    PubMed

    Gustafsson, L H

    1977-01-01

    Three studies on childhood accidents are presented. The aim was to study the importance of different factors regarding the accidents in question. The following factors have then been taken into consideration: the enviromental hazard, the accident proneness, the supervision and the education. Methodologically the investigations were carried out with an epidemiological technique. One is of a descriptive nature and the other two more analytically oriented. The studies are based on two different 1-year-materials consisting of accidents among children recorded in the emergency departments of Ostersund Hospital and the University Hospital in Uppsala. The results indicate that risk factors in the children's physical milieu played an important role in the occurrence of the accidents: clearly identifiable risk factors in the environment could be connected with 52% of the accidents, whereas some deficiency in supervision was noted in 20%. The investigators could identify a number of specific risk factors. Attempts were made to examine how frequency and type of childhood accidents vary with the population structure and social structure in well-defined housing areas, but the results were hard to evaluate because of methodological problems. The results are presented against the background of a detailed discussion on central methodological problems in epidemiological accident research. It is pointed out in particular that epidemiological methods have clear limitations in attempts at studying the low-frequency events that each individual type of accident in fact comprises. It is of great importance that in future research, side by side with the traditional epidemiological methods, other techniques are tested with the aim of obtaining maximal usable information from a detailed study of individual accidents and their backgrounds. PMID:857307

  11. 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

  12. Epidemiology of malaria in Malaysia.

    PubMed

    Rahman, K M

    1982-01-01

    Malaria is a major public health problem in Malaysia, particularly in peninsular Malaysia and the state of Sabah. An eradication program started in the states of Sabah and Sarawak in 1961 initially was remarkably successful. A similar but staged program was started in peninsular Malaysia in 1967 and was also quite successful. However, a marked upsurge in incidence in Sabah in 1975-1978 showed that malaria is still a major hazard. The disease leads to great economic losses in terms of the productivity of the labor force and the learning capacity of schoolchildren. The topography, the climate, and the migrations of the people due to increased economic activity are similar in peninsular Malaysia, Sabah, and Sarawak. However, the epidemiologic picture differs strikingly from area to area in terms of species of vectors, distribution of parasitic species, and resistance of Plasmodium falciparum to chloroquine. Likewise, the problems faced by the eradication or control programs in the three regions are dissimilar. Because solutions to only some of these problems are possible, the eradication of malaria in Malaysia is not likely in the near future. However, the situation offers an excellent opportunity for further studies of antimalaria measures. PMID:6755616

  13. Asthma exacerbations · 1: Epidemiology

    PubMed Central

    Johnston, N W; Sears, M R

    2006-01-01

    Asthma exacerbations may be triggered by a number of atmospheric and domiciliary environmental factors as well as by those encountered in schools and workplaces. The majority of exacerbations, particularly in children, coincide with respiratory viral infections, most commonly rhinovirus. As most respiratory viruses and many aeroallergens appear in seasonal patterns, asthma exacerbations, particularly those requiring emergency treatment, show analogous seasonal cycles which differ in form in children and adults. While similar in form between the sexes, they differ in amplitude, with boys having higher risks of exacerbation in childhood and women in adult life. Simultaneous exposure of asthmatics with respiratory viral infections to allergens or air pollutants may significantly increase the risks of exacerbation. Access to and compliance with inhaled corticosteroid treatment is an important predictor of the likelihood of asthma exacerbations occurring, including those that occur during respiratory viral infections. Epidemiologically, the degree of asthma control achieved by asthmatics is an important predictor of the likelihood of disease exacerbation including respiratory failure, death, and health service consumption. PMID:16877691

  14. Genetic Epidemiology in Aging Research

    PubMed Central

    Matteini, Amy

    2009-01-01

    Over the last two decades, aging research has expanded to include not only age-related disease models, and conversely, longevity and disease-free models, but also focuses on biological mechanisms related to the aging process. By viewing aging on multiple research frontiers, we are rapidly expanding knowledge as a whole and mapping connections between biological processes and particular age-related diseases that emerge. This is perhaps most true in the field of genetics, where variation across individuals has improved our understanding of aging mechanisms, etiology of age-related disease, and prediction of therapeutic responses. A close partnership between gerontologists, epidemiologists, and geneticists is needed to take full advantage of emerging genome information and technology and bring about a new age for biological aging research. Here we review current genetic findings for aging across both disease-specific and aging process domains. We then highlight the limitations of most work to date in terms of study design, genomic information, and trait modeling and focus on emerging technology and future directions that can partner genetic epidemiology and aging research fields to best take advantage of the rapid discoveries in each. PMID:19168782

  15. Epidemiologic features of canine hypothyroidism.

    PubMed

    Milne, K L; Hayes, H M

    1981-01-01

    This study investigates the epidemiologic features of 3,206 dogs diagnosed with hypothyroidism (including myxedema) from 1.1 million dogs seen at 15 veterinary teaching hospitals between March, 1964 and June, 1978. Nine breeds found to be at high-risk for hypothyroidism were: golden retrievers, Doberman pinschers, dachshunds, Shetland sheepdogs, Irish setters, Pomeranians, miniature schnauzers, cocker spaniels, and Airedales. Two breed with a significant deficit of risk were German shepherds and mixed breed (mongrel) dogs. Age risk was greatest among younger dogs of high-risk breeds, further suggesting a genetic component to the etiology of this disease. In contrast, low-risk dogs had increasing relative risk through nine years of age. Spayed female dogs displayed a significantly higher risk when compared to intact females. Though not statistically significant, male castrated dogs had 30% more hypothyroidism compared to their intact counterparts. Among the case series were 91 endocrine and hormone-related neoplasms and 198 other endocrine-related disorders. Further studies linking canine hypothyroidism to other conditions, particularly cancer, could provide valuable insight into human disease experience.

  16. 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. PMID:27531531

  17. 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

  18. [Pathophysiology and epidemiology of osteoporosis].

    PubMed

    Abendroth, K; Abendroth, B

    1995-02-01

    The international consensus definition characterizes the osteoporosis by low bone mass and microarchitectural deterioration. New genetic aspects of the pathogenesis of osteoporosis underline these characteristics. In the younger age, a reduced bone mineral density and a reduction of the bone structure are predictors of a genetically caused osteoporosis. The short-term maximal mechanical load of the bone structure by Frost (4) was pointed out to be an important pathophysiological element for the balance of the bone metabolism. Sex hormones and other calcium regulating hormones determine the effect of this biomechanical signal. The deficiency of the osteoblast's activity in the older age is caused by a reduced proliferating cell pool of bone tissue. The epidemiologic data of the osteoporosis were derived from incidence of the hip fractures. A densitometrical osteoporosis screening test analyzes only the bone density but not the organisation of the bone structure. There is too little informations about the disease of osteoporosis. It is to hope that, in the future, the European-Vertebral-Osteoporosis-Study will give additional knowledge about osteoporosis. PMID:7709645

  19. The epidemiology of ovarian cancer.

    PubMed

    Greene, M H; Clark, J W; Blayney, D W

    1984-09-01

    Although no unequivocally effective ovarian cancer prevention strategies have emerged, epidemiologic studies have identified high-risk populations. The striking international variation (apparently a fivefold difference) can probably be explained on the basis of differential parity, differing classification measures, and differences in the underlying population age distribution. United States age-adjusted mortality has increased slightly in the past 30 years, and the cancer remains predominantly a disease of older adult white women of northern European extraction. The increases in age-specific mortality and age-adjusted mortality over time may be related to a decrease in average family size. Pregnancy, especially pregnancy before age 25 years, and use of oral contraceptives are protective; the risk of ovarian cancer increases with increasing years of ovulation. A positive family history is also associated with a substantial increase in ovarian cancer risk. Survivors of ovarian cancer are more susceptible to cancers of the breast, endometrium, and colon than are similarly-aged normal women, most probably because all four cancers share some common risk factor(s). Various alkylating agents are clearly leukemogenic in survivors of ovarian cancer, an observation that suggests caution in the use of adjuvant chemotherapy in women at relatively low risk of relapse.

  20. Epidemiology of neurocysticercosis in Brazil.

    PubMed

    Agapejev, S

    1996-01-01

    A revision of literature was done with the objective of tracing an epidemiologic profile of neurocysticercosis (NCC) in Brazil. The prevalence was 0.12-9% in autopsies. The frequency was 0.03-7.5% in clinical series and 0.68-5.2% in seroepidemiological studies. The disease corresponds to 0.08-2.5% of admissions to general hospitals. Patient origin was rural in 30-63% of cases. The most involved age range (64-100%) was 11 to 60 years, with a predominance (22-67%) between 21 and 40 years. The male sex was the most affected (51-80%). In the severe forms there was a predominance of urban origin (53-62%) and of the female sex (53-75%). The period of hospitalization ranges from 1 to 254 days and 33 to 50% of patients suffer 1.7 +/- 1.4 admissions. The clinical picture was variable, with a predominance of epileptic syndrome (22-92%) and intracranial hypertension (19-89%). Psychiatric manifestations were associated in 9-23% of patients. Lethality was 0.29% in terms of all diseases in general and 4.8-25.9% in terms of neurologic diseases. The asymptomatic form was detected in 6% of patients in clinical series and in 48.5% of case from autopsies. The racemose form and ventricular localization also was observed as asymptomatic form. Among the patients with cutaneous cysticercosis 65% of them showed neurologic manifestations.

  1. 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.

  2. 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.

  3. 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

  4. Current issues in perinatal epidemiology.

    PubMed Central

    Berendes, H. W.

    1987-01-01

    The main national data sources for perinatal epidemiology are birth and death certificates, yet routinely linked birth and death certificate data are still not available in the U.S. Completeness and quality of the reporting of perinatal events should be considered in examining trends over time and between jurisdictions. The U.S. has experienced a marked decline in its infant mortality rate, but only a very modest decline in the rate of low birth weight. Research must focus more on studies of pre-term labor, rather than low birth weight, which include children who are underground or who are born too early and who, therefore, may represent different etiologies. Sensitive hormonal tests may provide more precise estimates of the rate of very early fetal loss. Management of labor and delivery and of the high-risk newborn have undergone marked changes during the last 15 years, and yet clinical trials have not played a major role in the evaluation of these changes. The difference in reproductive outcomes between whites and blacks, especially in the rate of low birth weight, have persisted and are not understood. Data bases are becoming available for intergenerational studies to determine whether nature or nurture accounts for this difference. PMID:3660860

  5. Genetic Epidemiology and Public Health: The Evolution From Theory to Technology.

    PubMed

    Fallin, M Daniele; Duggal, Priya; Beaty, Terri H

    2016-03-01

    Genetic epidemiology represents a hybrid of epidemiologic designs and statistical models that explicitly consider both genetic and environmental risk factors for disease. It is a relatively new field in public health; the term was first coined only 35 years ago. In this short time, the field has been through a major evolution, changing from a field driven by theory, without the technology for genetic measurement or computational capacity to apply much of the designs and methods developed, to a field driven by rapidly expanding technology in genomic measurement and computational analyses while epidemiologic theory struggles to keep up. In this commentary, we describe 4 different eras of genetic epidemiology, spanning this evolution from theory to technology, what we have learned, what we have added to the broader field of public health, and what remains to be done. PMID:26905340

  6. Genetic Epidemiology and Public Health: The Evolution From Theory to Technology.

    PubMed

    Fallin, M Daniele; Duggal, Priya; Beaty, Terri H

    2016-03-01

    Genetic epidemiology represents a hybrid of epidemiologic designs and statistical models that explicitly consider both genetic and environmental risk factors for disease. It is a relatively new field in public health; the term was first coined only 35 years ago. In this short time, the field has been through a major evolution, changing from a field driven by theory, without the technology for genetic measurement or computational capacity to apply much of the designs and methods developed, to a field driven by rapidly expanding technology in genomic measurement and computational analyses while epidemiologic theory struggles to keep up. In this commentary, we describe 4 different eras of genetic epidemiology, spanning this evolution from theory to technology, what we have learned, what we have added to the broader field of public health, and what remains to be done.

  7. Epidemiological applications: a case report of a village epidemic of gastroenteritis.

    PubMed

    Asuzu, M C; Singh, N

    2001-03-01

    This is a case report of an epidemic of gastroenteritis which was investigated and controlled by epidemiological methods only, before laboratory investigations could be done to confirm the original epidemiological conclusions--from contaminated home made ice-cubes. The case and process are reported in order to encourage similar uses of epidemiology by field public health practitioners, especially within the district or primary health care systems and particularly in places where laboratory support are difficult to avail. The case is used also to discuss the equipments and facilities that ought to be part of the support system for every modern field public health practitioner. These should include computers, modern communication facilities and epidemiological support systems, especially senior epidemiologists; as such senior personnel are available to junior colleagues in the other areas of specialist medical practice. PMID:12017811

  8. Merging economics and epidemiology to improve the prediction and management of infectious disease.

    PubMed

    Perrings, Charles; Castillo-Chavez, Carlos; Chowell, Gerardo; Daszak, Peter; Fenichel, Eli P; Finnoff, David; Horan, Richard D; Kilpatrick, A Marm; Kinzig, Ann P; Kuminoff, Nicolai V; Levin, Simon; Morin, Benjamin; Smith, Katherine F; Springborn, Michael

    2014-12-01

    Mathematical epidemiology, one of the oldest and richest areas in mathematical biology, has significantly enhanced our understanding of how pathogens emerge, evolve, and spread. Classical epidemiological models, the standard for predicting and managing the spread of infectious disease, assume that contacts between susceptible and infectious individuals depend on their relative frequency in the population. The behavioral factors that underpin contact rates are not generally addressed. There is, however, an emerging a class of models that addresses the feedbacks between infectious disease dynamics and the behavioral decisions driving host contact. Referred to as "economic epidemiology" or "epidemiological economics," the approach explores the determinants of decisions about the number and type of contacts made by individuals, using insights and methods from economics. We show how the approach has the potential both to improve predictions of the course of infectious disease, and to support development of novel approaches to infectious disease management.

  9. Epidemiology in the Era of Big Data

    PubMed Central

    Mooney, Stephen J; Westreich, Daniel J; El-Sayed, Abdulrahman M

    2015-01-01

    Big Data has increasingly been promoted as a revolutionary development in the future of science, including epidemiology. However, the definition and implications of Big Data for epidemiology remain unclear. We here provide a working definition of Big Data predicated on the so-called ‘3 Vs’: variety, volume, and velocity. From this definition, we argue that Big Data has evolutionary and revolutionary implications for identifying and intervening on the determinants of population health. We suggest that as more sources of diverse data become publicly available, the ability to combine and refine these data to yield valid answers to epidemiologic questions will be invaluable. We conclude that, while epidemiology as practiced today will continue to be practiced in the Big Data future, a component of our field’s future value lies in integrating subject matter knowledge with increased technical savvy. Our training programs and our visions for future public health interventions should reflect this future. PMID:25756221

  10. [The epidemiological surveillance of dengue in Mexico].

    PubMed

    Montesano-Castellanos, R; Ruiz-Matus, C

    1995-01-01

    The clinical behavior of dengue fever in Mexico has changed, now with the occurrence of hemorrhagic cases. In response to the emergence of such cases, a specific epidemiologic surveillance system has been designed and implemented. This system includes the means to monitor the factors involved in the evolution of the disease. The identification and analysis of these factors is necessary to implement prevention and control measures. This paper presents the main components and procedures of the epidemiologic surveillance system for common and hemorrhagic dengue fever in Mexico, emphasizing the usefulness of the risk approach to predict the pattern of this disease. The model includes the collaboration of a multidisciplinary group. The Epidemiologic Surveillance State Committee, coordinated by the National Health System, participates in the collection and analysis of epidemiologic data, particularly data related to the population, the individual, the vector, the viruses and the environment. PMID:8599150

  11. DESIGN OF EXPOSURE MEASUREMENTS FOR EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    This presentation will describe the following items: (1) London daily air pollution and deaths that demonstrate how time series epidemiology can indicate that air pollution caused death; (2) Sophisticated statistical models required to establish this relationship for lower pollut...

  12. 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.

  13. 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.

  14. [The epidemiological surveillance of dengue in Mexico].

    PubMed

    Montesano-Castellanos, R; Ruiz-Matus, C

    1995-01-01

    The clinical behavior of dengue fever in Mexico has changed, now with the occurrence of hemorrhagic cases. In response to the emergence of such cases, a specific epidemiologic surveillance system has been designed and implemented. This system includes the means to monitor the factors involved in the evolution of the disease. The identification and analysis of these factors is necessary to implement prevention and control measures. This paper presents the main components and procedures of the epidemiologic surveillance system for common and hemorrhagic dengue fever in Mexico, emphasizing the usefulness of the risk approach to predict the pattern of this disease. The model includes the collaboration of a multidisciplinary group. The Epidemiologic Surveillance State Committee, coordinated by the National Health System, participates in the collection and analysis of epidemiologic data, particularly data related to the population, the individual, the vector, the viruses and the environment.

  15. Epidemiology of tennis, squash, and racquetball injuries.

    PubMed

    Maylack, F H

    1988-04-01

    This article enumerates and examines the existing epidemiologic data on racquet sports injuries. A framework is provided for the evaluation and interpretation of future studies and research. PMID:3292063

  16. 16 CFR 1000.26 - Directorate for Epidemiology.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Directorate for Epidemiology. 1000.26 Section 1000.26 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL COMMISSION ORGANIZATION AND FUNCTIONS § 1000.26 Directorate for Epidemiology. The Directorate for Epidemiology, managed by the Associate Executive Director for Epidemiology,...

  17. 16 CFR 1000.26 - Directorate for Epidemiology.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Directorate for Epidemiology. 1000.26... AND FUNCTIONS § 1000.26 Directorate for Epidemiology. The Directorate for Epidemiology, managed by the Associate Executive Director for Epidemiology, is responsible for the collection and analysis of data...

  18. Design and analysis of metabolomics studies in epidemiologic research: a primer on -omic technologies.

    PubMed

    Tzoulaki, Ioanna; Ebbels, Timothy M D; Valdes, Ana; Elliott, Paul; Ioannidis, John P A

    2014-07-15

    Metabolomics is the field of "-omics" research concerned with the comprehensive characterization of the small low-molecular-weight metabolites in biological samples. In epidemiology, it represents an emerging technology and an unprecedented opportunity to measure environmental and other exposures with improved precision and far less measurement error than with standard epidemiologic methods. Advances in the application of metabolomics in large-scale epidemiologic research are now being realized through a combination of improved sample preparation and handling, automated laboratory and processing methods, and reduction in costs. The number of epidemiologic studies that use metabolic profiling is still limited, but it is fast gaining popularity in this area. In the present article, we present a roadmap for metabolomic analyses in epidemiologic studies and discuss the various challenges these data pose to large-scale studies. We discuss the steps of data preprocessing, univariate and multivariate data analysis, correction for multiplicity of comparisons with correlated data, and finally the steps of cross-validation and external validation. As data from metabolomic studies accumulate in epidemiology, there is a need for large-scale replication and synthesis of findings, increased availability of raw data, and a focus on good study design, all of which will highlight the potential clinical impact of metabolomics in this field. PMID:24966222

  19. How to make epidemiological training infectious.

    PubMed

    Bellan, Steve E; Pulliam, Juliet R C; Scott, James C; Dushoff, Jonathan

    2012-01-01

    Modern infectious disease epidemiology builds on two independently developed fields: classical epidemiology and dynamical epidemiology. Over the past decade, integration of the two fields has increased in research practice, but training options within the fields remain distinct with few opportunities for integration in the classroom. The annual Clinic on the Meaningful Modeling of Epidemiological Data (MMED) at the African Institute for Mathematical Sciences has begun to address this gap. MMED offers participants exposure to a broad range of concepts and techniques from both epidemiological traditions. During MMED 2010 we developed a pedagogical approach that bridges the traditional distinction between classical and dynamical epidemiology and can be used at multiple educational levels, from high school to graduate level courses. The approach is hands-on, consisting of a real-time simulation of a stochastic outbreak in course participants, including realistic data reporting, followed by a variety of mathematical and statistical analyses, stemming from both epidemiological traditions. During the exercise, dynamical epidemiologists developed empirical skills such as study design and learned concepts of bias while classical epidemiologists were trained in systems thinking and began to understand epidemics as dynamic nonlinear processes. We believe this type of integrated educational tool will prove extremely valuable in the training of future infectious disease epidemiologists. We also believe that such interdisciplinary training will be critical for local capacity building in analytical epidemiology as Africa continues to produce new cohorts of well-trained mathematicians, statisticians, and scientists. And because the lessons draw on skills and concepts from many fields in biology--from pathogen biology, evolutionary dynamics of host--pathogen interactions, and the ecology of infectious disease to bioinformatics, computational biology, and statistics--this exercise

  20. 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.

  1. The epidemiology of recurrent pregnancy loss.

    PubMed

    Cramer, D W; Wise, L A

    2000-01-01

    In reviewing the epidemiology of recurrent abortion (RAB), we believe it is necessary to consider the epidemiology of spontaneous abortion (SAB) as well, since it is clear that even a single pregnancy loss increases the risk for a subsequent abortion. In addition, any attempt to identify epidemiologic risk factors for SAB or RAB must deal with the fact that at least 50% of SABs are associated with genetic abnormalities. Given that most epidemiologic studies have not distinguished karyotypically abnormal abortuses, risk factors are likely to be underestimated. Nevertheless, there is fair agreement that a variety of factors may increase risk for SAB or RAB, including advanced maternal age, single gene mutations such as PKU or G6PD deficiency, structural abnormalities of the uterus, poorly controlled diabetes, antiphospholipid syndrome, and smoking. More controversial is the role of luteal phase defect or hyperandrogenism, alloimmune factors, genital infections, caffeine or alcohol use, and trace element or chemical exposure from tap water or in the workplace. Besides better designed epidemiologic studies to detect modifiable risk factors for SAB or RAB, there is a clear need for clinical trials of therapy for RAB which meet minimum epidemiologic standards including randomization, double-blinded (when possible), and placebo-controlled (when ethical).

  2. 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

  3. Epidemiology of hepatitis E virus in Iran.

    PubMed

    Taherkhani, Reza; Farshadpour, Fatemeh

    2016-06-14

    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

  4. Clinical and Epidemiological Characteristics of Kawasaki Disease

    PubMed Central

    Shamsizadeh, Ahmad; Ziaei Kajbaf, Tahereh; Razavi, Maryam; Cheraghian, Bahman

    2014-01-01

    Background: Kawasaki disease (KD) is an acute multisystem vascular syndrome of unknown etiology that is the leading cause of acquired heart disease in children of developed counties. Objectives: We aimed to evaluate the epidemiological characteristics and clinical manifestations of KD in children residing in the southwest of Iran. Patients and Methods: In this retrospective study, we reviewed the medical records of all children with KD who had been admitted to the main children’s hospital of Ahvaz, southwest Iran, from March 2000 to March 2010. Data regarding clinical and epidemiological characteristics, management, and the outcome of disease for each patient were obtained. The patients were divided into cardiac and non-cardiac groups based on echocardiographic results. Results: In total, 104 patients with KD (66 boys and 38 girls) were enrolled in this study. The male to female ratio was 1.7:1. The mean ± SD age of the patients was 33.6 ± 24.2 months. Most (87.2%) cases were from urban areas. The disease occurred more frequently during winter and spring. Furthermore, 61.5% of the children had the criteria of classic KD, and 38.5% were labeled as incomplete KD. The mean ± SD of the duration of hospital stay was 6.9 ± 2.4 days. The mean time between illness and admission to the hospital was 6.47 ± 2.6 days. The most common sign was fever, followed by conjunctivitis and oral changes. In total, 20% of the patients had cardiac abnormalities. There was no significant statistical difference between the cardiac and non-cardiac groups according to age, sex, clinical manifestations, laboratory findings, and cessation of fever. The duration of hospital stay and the time between onset of illness and diagnosis were longer in the cardiac group. All patients received intravenous immunoglobulin and aspirin. Only one patient continued to have cardiac abnormalities after 6 months of follow-up. Conclusions: Kawasaki disease is not rare in southwest of Iran. The age, gender

  5. COPD in Taiwan: a National Epidemiology Survey

    PubMed Central

    Cheng, Shih-Lung; Chan, Ming-Cheng; Wang, Chin-Chou; Lin, Ching-Hsiung; Wang, Hao-Chien; Hsu, Jeng-Yuan; Hang, Liang-Wen; Chang, Chee-Jen; Perng, Diahn-Warng; Yu, Chong-Jen

    2015-01-01

    Objectives To determine the prevalence of COPD in Taiwan and to document the disease characteristics and associated risk factors. Methods We conducted a random cross-sectional national survey of adults older than 40 years in Taiwan. Respiratory health screening questions identified subjects with diagnosed COPD or whose reported symptoms also fulfilled an epidemiological case definition; these were eligible to complete the survey, which also included indices of symptom severity and disability and questions on comorbidities, medical treatments, smoking habits, and occupations potentially harmful to respiratory health. Subjects with diagnosed COPD were subdivided by smoking status. Subjects who fulfilled the case definition of COPD and smoked were designated as “possible COPD”. Participants who did not fit the case definition of COPD were asked only about their personal circumstances and smoking habits. Data from these groups were analyzed and compared. Results Of the 6,600 participants who completed the survey, 404 (6.1%) fulfilled the epidemiological case definition of COPD: 137 with diagnosed COPD and 267 possible COPD. The most common comorbidities of COPD were hypertension or cardiovascular diseases (36.1%). Subjects with definite COPD had significantly higher COPD Assessment Test scores than the possible COPD group (14.6±8.32 vs 12.6±6.49, P=0.01) and significantly more comorbid illnesses (P=0.01). The main risk factors contributing to health care utilization in each COPD cohort were higher COPD Assessment Test scores (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.04–1.26), higher modified Medical Research Council Breathlessness Scale scores (OR 1.97, 95% CI 1.11–3.51), and having more than one comorbidity (OR 5.19, 95% CI 1.05–25.61). Conclusion With estimated prevalence of 6.1% in the general population, COPD in Taiwan has been underdiagnosed. Symptoms and comorbidities were independent risk factors for health care utilization in subjects

  6. 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

  7. Evaluation metrics for biostatistical and epidemiological collaborations.

    PubMed

    Rubio, Doris McGartland; Del Junco, Deborah J; Bhore, Rafia; Lindsell, Christopher J; Oster, Robert A; Wittkowski, Knut M; Welty, Leah J; Li, Yi-Ju; Demets, Dave

    2011-10-15

    Increasing demands for evidence-based medicine and for the translation of biomedical research into individual and public health benefit have been accompanied by the proliferation of special units that offer expertise in biostatistics, epidemiology, and research design (BERD) within academic health centers. Objective metrics that can be used to evaluate, track, and improve the performance of these BERD units are critical to their successful establishment and sustainable future. To develop a set of reliable but versatile metrics that can be adapted easily to different environments and evolving needs, we consulted with members of BERD units from the consortium of academic health centers funded by the Clinical and Translational Science Award Program of the National Institutes of Health. Through a systematic process of consensus building and document drafting, we formulated metrics that covered the three identified domains of BERD practices: the development and maintenance of collaborations with clinical and translational science investigators, the application of BERD-related methods to clinical and translational research, and the discovery of novel BERD-related methodologies. In this article, we describe the set of metrics and advocate their use for evaluating BERD practices. The routine application, comparison of findings across diverse BERD units, and ongoing refinement of the metrics will identify trends, facilitate meaningful changes, and ultimately enhance the contribution of BERD activities to biomedical research.

  8. Epidemiology of psychosis in Parkinson's disease.

    PubMed

    Fénelon, Gilles; Alves, Guido

    2010-02-15

    Psychotic symptoms are frequent and disabling in patients with Parkinson's disease (PD). Methodological issues in the epidemiology of PD associated psychosis (PDP) include differences in the symptoms assessed, the methods of assessment, and the selection of patients. Most studies are prospective clinic-based cross-sectional studies providing point prevalence rates in samples on dopaminergic treatment. Visual hallucinations are present in about one quarter to one third of the patients, auditory in up to 20%. Tactile/somatic, and olfactory hallucinations are usually not systematically sought. Minor phenomena such as sense of presence and visual illusions affect 17 to 72% of the patients, and delusions about 5%. Lifetime prevalence of visual hallucinations reaches approximately 50%. Prospective longitudinal cohort studies suggest that hallucinations persist and worsen in individual patients, and that their prevalence increases with time. A facilitating role of treatment on PDP is demonstrated at least for dopaminergic agonists, but there is no simple dose-effect relationship between dopaminergic treatment and the presence or severity of hallucinations. The main endogenous non-modifiable risk factor is cognitive impairment. Other associated factors include older age/longer duration of PD, disease severity, altered dream phenomena, daytime somnolence, and possibly depression and dysautonomia. PDP reduces quality of life in patients and increases caregiver distress, and is an independent risk factor for nursing home placement and development of dementia. PMID:19740486

  9. Epidemiology, Mechanisms and Management of Diabetic Gastroparesis

    PubMed Central

    Camilleri, Michael; Bharucha, Adil E.; Farrugia, Gianrico

    2010-01-01

    Background Recent evidence of the significant impact of gastroparesis on morbidity and mortality mandates optimized management of this condition. Gastroparesis affects nutritional state and, in diabetics, it also has deleterious effects on glycemic control and secondary effects on organs that lead to increased mortality. First-line treatment includes restoration of nutrition and medications (prokinetic and antiemetic). Aim To review the epidemiology, pathophysiology, impact, natural history, time trends and treatment of gastroparesis with particular focus on diabetic gastroparesis. Methods The pros and cons of current treatment options including metoclopramide are discussed. Second-line approaches include surgery, venting gastrostomy or jejunostomy, and gastric electrical stimulation; most of these treatments are based on open-label treatment trials. Results/Conclusions In the future, drugs that target the underlying defects and new prokinetics such as newer 5-HT4 agonists (which appear to be devoid of cardiac or vascular effects), ghrelin agonists, new approaches to pacing the stomach, and stem cell therapies may bring more effective treatments to ameliorate the management of patients with gastroparesis. PMID:20951838

  10. Epidemiology of Rheumatoid Arthritis in Southern Albania

    PubMed Central

    Koko, Vjollca; Ndrepepa, Ana; Skenderaj, Skender

    2015-01-01

    Objectives: The aim of this study was to assess the prevalence, incidence and the burden of rheumatoid arthritis (RA) in the Southern Albania. Material and Methods: This is an epidemiologic observational study with cross-sectional analyses of all patients with RA who lived in Southern Albania during the 1995-2011 years. The RA prevalence, incidence and disability-adjusted life years (DALY) were assessed. Results: During the 1995-2011 years, 194 patients (154 females and 40 males) with RA living in Southern Albania were identified. The prevalence of RA in 2011 was 0.25% in general population and 0.34% in adult (>14 years) population. The incidence of RA in 2011 was 0.012% (12 new cases per 100000 inhabitants) and 0.016% (16 new cases per 100000 adults). The prevalence increased (from 0.036% in 1996 to 0.25% in 2011) and the incidence did not change over the study period. The mortality was 3.2% (n=7 deaths). The DALY due to RA was 823 years per 100000 inhabitants during 1995-2011 years. Conclusion: RA in Southern Albania has a prevalence of 0.25 % and an annual incidence of 0.012% in the general population in 2011. RA was responsible for a considerable burden on the health of population during the 1995-2011 years. PMID:26236163

  11. Epidemiology of psychosis in Parkinson's disease.

    PubMed

    Fénelon, Gilles; Alves, Guido

    2010-02-15

    Psychotic symptoms are frequent and disabling in patients with Parkinson's disease (PD). Methodological issues in the epidemiology of PD associated psychosis (PDP) include differences in the symptoms assessed, the methods of assessment, and the selection of patients. Most studies are prospective clinic-based cross-sectional studies providing point prevalence rates in samples on dopaminergic treatment. Visual hallucinations are present in about one quarter to one third of the patients, auditory in up to 20%. Tactile/somatic, and olfactory hallucinations are usually not systematically sought. Minor phenomena such as sense of presence and visual illusions affect 17 to 72% of the patients, and delusions about 5%. Lifetime prevalence of visual hallucinations reaches approximately 50%. Prospective longitudinal cohort studies suggest that hallucinations persist and worsen in individual patients, and that their prevalence increases with time. A facilitating role of treatment on PDP is demonstrated at least for dopaminergic agonists, but there is no simple dose-effect relationship between dopaminergic treatment and the presence or severity of hallucinations. The main endogenous non-modifiable risk factor is cognitive impairment. Other associated factors include older age/longer duration of PD, disease severity, altered dream phenomena, daytime somnolence, and possibly depression and dysautonomia. PDP reduces quality of life in patients and increases caregiver distress, and is an independent risk factor for nursing home placement and development of dementia.

  12. Epidemiological study of cauda equina syndrome

    PubMed Central

    Fuso, Fernando Augusto Freitas; Dias, André Luiz Natálio; Letaif, Olavo Biraghi; Cristante, Alexandre Fogaça; Marcon, Raphael Martus; de Barros, Tarcísio Eloy Pessoa

    2013-01-01

    OBJECTIVE : The primary purpose of this study was to determine the characteristics and outcomes of the patients admitted at our clinics diagnosed with cauda equina syndrome (CES). Secondarily, this study will serve as a basis for other comparative studies aiming at a better understanding of this condition and its epidemiology. METHODS : We conducted a retrospective study by reviewing the medical records of patients diagnosed with CES and neurogenic bladder between 2005 and 2011. The following variables were analyzed: gender, age, etiology, topographic level of the lesion, time between disease onset and diagnosis, presence of neurogenic bladder, time between diagnosis and surgery, neurological damage and neurogenic bladder persistence. RESULTS : Considering that CES is a rare condition, we were not able to establish statistic correlation between the analyzed variables and the outcomes of the disease. However, this study brought to light the inadequacy of our public health system in treating that kind of patient. CONCLUSION : The study shows that despite the well-defined basis for managing CES, we noted a greater number of patients with sequels caused by this condition, than is seen in the literature. The delayed diagnosis and, consequently, delayed treatment, were the main causes for the results observed. Level of Evidence IV, Case Series. PMID:24453661

  13. 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

  14. Epidemiology of Nursemaid’s Elbow

    PubMed Central

    Vitello, Sarah; Dvorkin, Ronald; Sattler, Steven; Levy, David; Ung, Lyncean

    2014-01-01

    Introduction To provide an epidemiological description of radial head subluxation, also known as nursemaid’s elbow, from a database of emergency department visits. Methods We conducted a retrospective medical record review of patients 6 years of age and younger, who presented to the ED between January 1, 2005, and December 31, 2012, and were diagnosed with nursemaid’s elbow. Inclusion criteria consisted of chart information, including date, unique account number, medical record number, weight, age, sex, and arm affected. Exclusion criteria included any charts with missing or incomplete data. Results There were 1,228 charts that met inclusion criteria. The majority of patients were female (60%). The mean age was 28.6 months (±12.6). The left arm was affected 60% of the time. Most of the included patients were over the 75th percentile for weight and more than one quarter were over the 95th percentile in each gender. Conclusion The average age of children presenting with nursemaid’s elbow was 28.6 months. Females were affected more than males, and the left arm was predominately affected. Most patients were above the 75th percentile for weight and more than one quarter were over the 95th percentile for weight. PMID:25035767

  15. History, epidemiology and regional diversities of urolithiasis.

    PubMed

    López, Michelle; Hoppe, Bernd

    2010-01-01

    Archeological findings give profound evidence that humans have suffered from kidney and bladder stones for centuries. Bladder stones were more prevalent during older ages, but kidney stones became more prevalent during the past 100 years, at least in the more developed countries. Also, treatment options and conservative measures, as well as 'surgical' interventions have also been known for a long time. Our current preventive measures are definitively comparable to those of our predecessors. Stone removal, first lithotomy for bladder stones, followed by transurethral methods, was definitively painful and had severe side effects. Then, as now, the incidence of urolithiasis in a given population was dependent on the geographic area, racial distribution, socio-economic status and dietary habits. Changes in the latter factors during the past decades have affected the incidence and also the site and chemical composition of calculi, with calcium oxalate stones being now the most prevalent. Major differences in frequency of other constituents, particularly uric acid and struvite, reflect eating habits and infection risk factors specific to certain populations. Extensive epidemiological observations have emphasized the importance of nutritional factors in the pathogenesis of urolithiasis, and specific dietary advice is, nowadays, often the most appropriate for prevention and treatment of urolithiasis.

  16. Bacterial population genetics, evolution and epidemiology.

    PubMed Central

    Spratt, B G; Maiden, M C

    1999-01-01

    Asexual bacterial populations inevitably consist of an assemblage of distinct clonal lineages. However, bacterial populations are not entirely asexual since recombinational exchanges occur, mobilizing small genome segments among lineages and species. The relative contribution of recombination, as opposed to de novo mutation, in the generation of new bacterial genotypes varies among bacterial populations and, as this contribution increases, the clonality of a given population decreases. In consequence, a spectrum of possible population structures exists, with few bacterial species occupying the extremes of highly clonal and completely non-clonal, most containing both clonal and non-clonal elements. The analysis of collections of bacterial isolates, which accurately represent the natural population, by nucleotide sequence determination of multiple housekeeping loci provides data that can be used both to investigate the population structure of bacterial pathogens and for the molecular characterization of bacterial isolates. Understanding the population structure of a given pathogen is important since it impacts on the questions that can be addressed by, and the methods and samples required for, effective molecular epidemiological studies. PMID:10365396

  17. spa typing for epidemiological surveillance of Staphylococcus aureus.

    PubMed

    Hallin, Marie; Friedrich, Alexander W; Struelens, Marc J

    2009-01-01

    The spa typing method is based on sequencing of the polymorphic X region of the protein A gene (spa), present in all strains of Staphylococcus aureus. The X region is constituted of a variable number of 24-bp repeats flanked by well-conserved regions. This single-locus sequence-based typing method combines a number of technical advantages, such as rapidity, reproducibility, and portability. Moreover, due to its repeat structure, the spa locus simultaneously indexes micro- and macrovariations, enabling the use of spa typing in both local and global epidemiological studies. These studies are facilitated by the establishment of standardized spa type nomenclature and Internet shared databases.

  18. Laboratory identification and epidemiology of streptococcal hospital isolates.

    PubMed

    Hardy, M A; Dalton, H P; Allison, M J

    1978-11-01

    A total of 343 streptococcal strains were identified to species on the basis of the progressive method of bacterial identification as advocated by Cowan & Steel's Manual for the Identification of Medical Bacteria. Comparative studies were also performed with these strains to determine the accuracy and feasibility of using various types of blood, differential media, and biochemical tests in conjunction with the progressive method of identification. The streptococcal species were then correlated with the type of specimen, sex, and age of hospitalized patients to obtain some insight into the epidemiology of hospital streptococcal isolates.

  19. 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.

  20. [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

  1. Epidemiological Dynamics and Phylogeography of Influenza Virus in Southern China

    PubMed Central

    Cheng, Xiaowen; Tan, Yi; He, Mingliang; Lam, Tommy Tsan-Yuk; Lu, Xing; Viboud, Cécile; He, Jianfan; Zhang, Shunxiang; Lu, Jianhua; Wu, Chunli; Fang, Shishong; Wang, Xin; Xie, Xu; Ma, Hanwu; Nelson, Martha I.; Kung, Hsiang-fu; Holmes, Edward C.; Cheng, Jinquan

    2013-01-01

    Background. Understanding the epidemiological dynamics of influenza virus is central to surveillance and vaccine strain selection. It has been suggested that tropical and subtropical regions represent the global source of influenza epidemics. However, our understanding of the epidemiological dynamics of influenza virus in these regions is limited by a relative lack of long-term data. Methods. We analyzed epidemiological and virological data on influenza recorded over a period of 15 years from the metropolitan city of Shenzhen in subtropical southern China. We used wavelet analysis to determine the periodicity of influenza epidemics and molecular phylogeographic analysis to investigate the role of Shenzhen and southern China in the global evolution of influenza virus. Results. We show that southern China is unlikely to represent an epicenter of global influenza activity, because activity in Shenzhen is characterized by significant annual cycles, multiple viral introductions every year, limited persistence across epidemic seasons, and viruses that generally are not positioned on the trunk of the global influenza virus phylogeny. Conclusions. We propose that novel influenza viruses emerge and evolve in multiple geographic localities and that the global evolution of influenza virus is complex and does not simply originate from a southern Chinese epicenter. PMID:22930808

  2. 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

  3. 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

  4. 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

  5. Advances in psychiatric epidemiology: rates and risks for major depression.

    PubMed Central

    Weissman, M M

    1987-01-01

    Over the last decade there has been a marked increase in information on the epidemiology of psychiatric disorders, particularly major depression, in adults living in the community and in families. The ability to conduct large epidemiologic studies of psychiatric disorders is due to improvements in diagnostic precision and reliability in psychiatry and to the development of systematic methods for collecting information on signs and symptoms to make diagnoses. Results from a recently completed epidemiologic survey of psychiatric disorders in five urban communities in the United States and from several large-scale family genetic studies suggest that major depression is a highly prevalent disorder. It occurs in adults and children, and there is evidence for an increased rate in younger people. The average age of first onset is in young adulthood. Most depressions are untreated. The firm risk factors for major depression include being female; young (born after World War II); separated/divorced or in an unhappy marriage; and having a family history of major depression. There is a two-to-threefold increased risk for major depression if there is a family history of the disorder. The relevance of these findings to clinical practice and public health is discussed. PMID:3826462

  6. 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

  7. Anxiety: Its Role in the History of Psychiatric Epidemiology

    PubMed Central

    Murphy, Jane M.; Leighton, Alexander H.

    2013-01-01

    Background The role played by anxiety in the history of psychiatric epidemiology has not been well recognized. Such lack of understanding retarded the growth of psychiatric research in general populations. It seems useful to look back on this history while deliberations are being carried out about how anxiety will be presented in DSM-V. Methods Drawing on the literature and our own research, we examine work that was carried out during and after the Second World War by a Research Branch of the United States War Department, by the Stirling County Study, and by the Midtown Manhattan Study. The differential influences of Meyerian psychobiology and Freudian psychoanalysis are noted. Results The instruments developed in the early epidemiologic endeavors used questions about nervousness, palpitations, sweating, trembling, shortness of breath, upset stomach, etc. These symptoms are important features of what the clinical literature called “manifest”, “free-floating”, or “chronic anxiety”. A useful descriptive name is “autonomic anxiety”. Conclusions Although not focusing on specific circumstances as in Panic and Phobic Disorders, a non-specific form of autonomic anxiety is a common, disabling, and usually chronic disorder that received empirical verification in studies of several community populations. It is suggested that two types of general anxiety may need to be recognized-- one dominated by excessive worry and feelings of stress, as in the current DSM-IV definition of Generalized Anxiety Disorder, and another emphasizing frequent unexplainable autonomic fearfulness, as in the early epidemiologic studies. PMID:18940025

  8. 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

  9. Epidemiology, Policy, and Racial/Ethnic Minority Health Disparities

    PubMed Central

    Carter-Pokras, Olivia; Offutt-Powell, Tabatha; Kaufman, Jay S.; Giles, Wayne; Mays, Vickie

    2013-01-01

    Purpose Epidemiologists have long contributed to policy efforts to address health disparities. Three examples illustrate how epidemiologists have addressed health disparities in the U.S. and abroad through a “social determinants of health” lens. Methods To identify examples of how epidemiologic research has been applied to reduce health disparities, we queried epidemiologists engaged in disparities research in the U.S., Canada, and New Zealand, and drew upon the scientific literature. Results Resulting examples covered a wide range of topic areas. Three areas selected for their contributions to policy were: 1) epidemiology's role in definition and measurement, 2) the study of housing and asthma, and 3) the study of food policy strategies to reduce health disparities. While epidemiologic research has done much to define and quantify health inequalities, it has generally been less successful at producing evidence that would identify targets for health equity intervention. Epidemiologists have a role to play in measurement and basic surveillance, etiologic research, intervention research, and evaluation research. However, our training and funding sources generally place greatest emphasis on surveillance and etiologic research. Conclusions: The complexity of health disparities requires better training for epidemiologists to effectively work in multidisciplinary teams. Together we can evaluate contextual and multilevel contributions to disease and study intervention programs in order to gain better insights into evidenced-based health equity strategies. PMID:22626003

  10. 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.

  11. 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

  12. The Schisto Track: A System for Gathering and Monitoring Epidemiological Surveys by Connecting Geographical Information Systems in Real Time

    PubMed Central

    2014-01-01

    Background Using the Android platform as a notification instrument for diseases and disorders forms a new alternative for computerization of epidemiological studies. Objective The objective of our study was to construct a tool for gathering epidemiological data on schistosomiasis using the Android platform. Methods The developed application (app), named the Schisto Track, is a tool for data capture and analysis that was designed to meet the needs of a traditional epidemiological survey. An initial version of the app was finished and tested in both real situations and simulations for epidemiological surveys. Results The app proved to be a tool capable of automation of activities, with data organization and standardization, easy data recovery (to enable interfacing with other systems), and totally modular architecture. Conclusions The proposed Schisto Track is in line with worldwide trends toward use of smartphones with the Android platform for modeling epidemiological scenarios. PMID:25099881

  13. Genomic Signatures of Emerging Viruses: A New Era of Systems Epidemiology.

    PubMed

    Rasmussen, Angela L; Katze, Michael G

    2016-05-11

    Compared to classical epidemiologic methods, genomics can be used to precisely monitor virus evolution and transmission in real time across large, diverse populations. Integration of pathogen genomics with data about host genetics and global transcriptional responses to infection allows for comprehensive studies of population-level responses to infection and provides novel methods for predicting clinical outcomes. As genomic technologies become more accessible, these methods will redefine how emerging viruses are studied and outbreaks are contained. Here we review the existing and emerging genomic technologies that are enabling systems epidemiology and systems virology and making it possible to respond rapidly to emerging viruses such as Zika.

  14. 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.

  15. Review of epidemiological studies on the occupational risk of tuberculosis in low-incidence areas.

    PubMed

    Seidler, Andreas; Nienhaus, Albert; Diel, Roland

    2005-01-01

    This review summarizes the epidemiological evidence for occupationally acquired tuberculosis and considers the implications for the prevention of tuberculosis. The relevant epidemiological studies were identified on the basis of the Medline data bank, starting with the year 1966. The evaluation of occupational groups with an elevated tuberculosis risk is exclusively based on epidemiologic studies of good or acceptable quality, applying clearly defined criteria of methodological quality. In summary, the available epidemiological evidence suggests that the risk of tuberculosis is elevated in the following occupational groups: hospital employees in wards with tuberculosis patients; nurses in hospitals; nurses attending HIV-positive or drug-addicted patients; pathology and laboratory workers; respiratory therapists and physiotherapists; physicians in internal medicine, anaesthesia, surgery and psychiatry; non-medical hospital personnel in housekeeping and transport work; funeral home employees, and prison employees. However, the epidemiological evidence is limited for all these occupations, with the exception of the nurses, because of the lack of methodologically adequate studies that have got the statistical power to differentiate between specific work tasks. There is a need for large population-based studies with precise definition of exposure, which should include molecular epidemiologic methods in the investigation of occupational risk factors of tuberculosis. PMID:16088290

  16. The contribution of molecular epidemiology to the understanding and control of viral diseases of salmonid aquaculture.

    PubMed

    Snow, Michael

    2011-01-01

    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.

  17. 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. PMID:26311794

  18. 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.

  19. [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.

  20. 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

  1. Choosing a future for epidemiology: II. From black box to Chinese boxes and eco-epidemiology.

    PubMed Central

    Susser, M; Susser, E

    1996-01-01

    Part I of this paper traced the evolution of modern epidemiology in terms of three eras, each with its dominant paradigm, culminating in the present era of chronic disease epidemiology with its paradigm, the black box. This paper sees the close of the present era and foresees a new era of eco-epidemiology in which the deployment of a different paradigm will be crucial. Here a paradigm is advocated for the emergent era. Encompassing many levels of organization--molecular and societal as well as individual--this paradigm, termed Chinese boxes, aims to integrate more than a single level in design, analysis, and interpretation. Such a paradigm could sustain and refine a public health-oriented epidemiology. But preventing a decline of creative epidemiology in this new era will require more than a cogent scientific paradigm. Attention will have to be paid to the social processes that foster a cohesive and humane discipline. PMID:8629718

  2. 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

  3. Epidemiological and molecular characteristics of meticillin-resistant Staphylococcus aureus in Turkey: A multicentre study.

    PubMed

    Dündar, Devrim; Willke, Ayse; Sayan, Murat; Koc, Meliha Meric; Akan, Ozay Arıkan; Sumerkan, Bulent; Saltoglu, Nese; Yaman, Akgun; Ayaz, Celal; Koksal, Iftihar

    2016-09-01

    The aim of this study was to investigate the epidemiological and molecular features of clinical meticillin-resistant Staphylococcus aureus (MRSA) isolates in Turkey. MRSA isolates were collected from six regions of Turkey. The mecA and nuc genes were detected by PCR. Antimicrobial susceptibilities were determined by the disk diffusion method. Staphylococcal cassette chromosome mec (SCCmec) and staphylococcal protein A (spa) typing were performed by the sequencing method for 270 randomly selected MRSA isolates. The US Centers for Disease Control and Prevention (CDC) definition was used for epidemiological diagnosis of community-associated MRSA (CA-MRSA). Resistance rates of MRSA to ciprofloxacin, gentamicin, clindamycin, erythromycin, rifampicin, trimethoprim/sulfamethoxazole and tetracycline were 93.4%, 81.2%, 38.5%, 57.8%, 93.9%, 1.1% and 93.1%, respectively. The most frequent SCCmec type was SCCmec III (91.1%). SCCmec type IV was found in 5.2% of the isolates. The most frequent spa type was t030 (81.1%). Five isolates were CA-MRSA if only the epidemiological definition was used (5/725; 0.7%). Two isolates were defined as CA-MRSA both by epidemiological features and SCCmec typing (2/270; 0.7%). Of 14 SCCmec type IV isolates, 12 were not defined as CA-MRSA by epidemiological features. In conclusion, this is the most comprehensive multicentre study in Turkey investigating MRSA using both epidemiological and genotypic features. The CA-MRSA rate is low in Turkey. Combined use of epidemiological and genotypic methods is the most accurate approach for the diagnosis of CA-MRSA.

  4. Evolution of environmental epidemiologic risk assessment.

    PubMed

    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.

  5. 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

  6. 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

  7. 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.

  8. Epidemiology of child psychopathology: major milestones.

    PubMed

    Verhulst, Frank C; Tiemeier, Henning

    2015-06-01

    Child psychiatric epidemiology has developed rapidly from descriptive, cross-sectional studies in the 1960s to the current large-scale prospective cohorts that unravel aetiological mechanisms. The objective of the study was to give an overview of epidemiological studies that have influenced child psychiatry. A chronological overview of selected major milestone studies was obtained to demonstrate the development of child psychiatric epidemiology, with a more in-depth discussion of findings and methodological issues exemplified in one cohort, the Generation R Study. Epidemiological studies have been successful in describing the frequency and course of child psychiatric problems. The high expectations that biological factors can be used to better explain, diagnose or predict child psychiatric problems have not been met. More ambitious large-scale child psychiatric cohort studies are needed, carefully applying genetics, neuroscience or other molecular research to better understand how the brain produces maladaptive behaviour. Progress will only be attained if the basic sciences are systematically integrated in cohorts with rigorous epidemiological designs rather than hurriedly inserted in child psychiatric studies.

  9. Hierarchical regression for epidemiologic analyses of multiple exposures.

    PubMed Central

    Greenland, S

    1994-01-01

    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 "semi-Bayes" 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. PMID:7851328

  10. 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.

  11. 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

  12. [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

  13. [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

  14. 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. PMID:26744813

  15. [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. PMID:25230524

  16. 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

  17. Epidemiology of cryptosporidiosis among European AIDS patients.

    PubMed Central

    Pedersen, C; Danner, S; Lazzarin, A; Glauser, M P; Weber, R; Katlama, C; Barton, S E; Lundgren, J D

    1996-01-01

    OBJECTIVE: To study epidemiology and possible risk factors associated with the development of cryptosporidiosis among European patients with AIDS. METHODS: An inception cohort of 6548 patients with AIDS, consecutively diagnosed from 1979 to 1989, from 52 centres in 17 European countries was studied. Data on all AIDS defining events were collected retrospectively from patients' clinical records. Kaplan-Meier estimates, log rank tests and Cox proportional hazard models were used to examine for possible risk factors associated with cryptosporidiosis. RESULTS: Cryptosporidiosis was diagnosed in 432 (6.6%) patients, 216 at time of the AIDS diagnosis and 216 during follow-up. The probability of being diagnosed with cryptosporidiosis at AIDS diagnosis was significantly lower for intravenous drug users (1.3%) than for homosexual men (4.1%) and for patients belonging to other transmission categories (4.0%) (p < 0.001). The probability was also higher for patients from Central Europe compared with patients from South Europe (4.1% versus 2.5%, p = 0.005). The rate of developing cryptosporidiosis after the diagnosis of AIDS was 3 per 100 patient years of follow-up. The rate was significantly lower for intravenous drug users than for homosexual men (relative risk 0.34, 95% confidence limits 0.22-0.54) and for women compared with men (RR 0.43 (0.21-0.87)). The risk was higher in North Europe than in South and Central Europe. In a multivariate analysis only transmission category remained a significant predictor for the development of cryptosporidiosis. CONCLUSION: The development of cryptosporidiosis in AIDS patients may be associated with sexual risk behaviour. PMID:8698361

  18. 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

  19. Spatial Epidemiology: Current Approaches and Future Challenges

    PubMed Central

    Elliott, Paul; Wartenberg, Daniel

    2004-01-01

    Spatial epidemiology is the description and analysis of geographic variations in disease with respect to demographic, environmental, behavioral, socioeconomic, genetic, and infectious risk factors. We focus on small-area analyses, encompassing disease mapping, geographic correlation studies, disease clusters, and clustering. Advances in geographic information systems, statistical methodology, and availability of high-resolution, geographically referenced health and environmental quality data have created unprecedented new opportunities to investigate environmental and other factors in explaining local geographic variations in disease. They also present new challenges. Problems include the large random component that may predominate disease rates across small areas. Though this can be dealt with appropriately using Bayesian statistics to provide smooth estimates of disease risks, sensitivity to detect areas at high risk is limited when expected numbers of cases are small. Potential biases and confounding, particularly due to socioeconomic factors, and a detailed understanding of data quality are important. Data errors can result in large apparent disease excess in a locality. Disease cluster reports often arise nonsystematically because of media, physician, or public concern. One ready means of investigating such concerns is the replication of analyses in different areas based on routine data, as is done in the United Kingdom through the Small Area Health Statistics Unit (and increasingly in other European countries, e.g., through the European Health and Environment Information System collaboration). In the future, developments in exposure modeling and mapping, enhanced study designs, and new methods of surveillance of large health databases promise to improve our ability to understand the complex relationships of environment to health. PMID:15198920

  20. Investigating the spatial micro-epidemiology of diseases within a point-prevalence sample: a field applicable method for rapid mapping of households using low-cost GPS-dataloggers.

    PubMed

    Stothard, J Russell; Sousa-Figueiredo, Jose C; Betson, Martha; Seto, Edmund Y W; Kabatereine, Narcis B

    2011-09-01

    Point-prevalence recording of the distribution of tropical parasitic diseases at village level is usually sufficient for general monitoring and surveillance. Whilst within-village spatial patterning of diseases exists, and can be important, mapping infected cases in a household-by-household setting is arduous and time consuming. With the development of low-cost GPS-data loggers (< £40) and available GoogleEarth(TM) satellite imagery, we present a field-applicable method based on crowdsourcing for rapid identification of infected cases (intestinal schistosomiasis, malaria and hookworm) by household. A total of 126 mothers with their 247 preschool children from Bukoba village (Mayuge District, Uganda) were examined with half of these mothers given a GPS-data logger to walk home with, returning the unit the same day for data off-loading, after which, households were assigned GPS coordinates. A satellite image of Bukoba was annotated with households denoting the infection status of each mother and child. General prevalence of intestinal schistosomiasis, malaria and hookworm in mothers and children was: 27.2 vs 7.7%, 28.6 vs 87.0% and 60.0 vs 22.3%, respectively. Different spatial patterns of disease could be identified likely representing the intrinsic differences in parasite biology and interplay with human behaviour(s) across this local landscape providing a better insight into reasons for disease micro-patterning.

  1. Epidemiological measures in planning: observations from Sweden.

    PubMed

    Rosén, M

    1988-01-01

    This article reviews how epidemiological measures can be used in health planning. Theoretical considerations are discussed together with empirical data from Sweden. Formulation of targets, priority settings, resource allocation and monitoring systems are some ways in which epidemiological data can improve health planning. One important lesson for planning is that problems related to health, inequalities in health, and access to care, must be made visible to politicians, health personnel and the public. Further, there is a need to complement a national health policy with a decentralized planning system that takes local conditions and needs into consideration.

  2. 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

  3. Epidemiology of Inflammatory Breast Cancer (IBC)1

    PubMed Central

    Anderson, William F.; Schairer, Catherine; Chen, Bingshu E.; Hance, Kenneth W.; Levine, Paul H.

    2010-01-01

    Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer with unknown etiology and generally poor outcome. It is characterized by diffuse edema (peau d'orange) and redness (erythema), although either the disease itself or case definitions have varied over time and place, confounding temporal trends and geographic variations. In this review, we discuss case definitions for IBC and its clinical characteristics; describe its geographic variation, age and racial distribution, incidence and survival patterns, and summarize the very limited information on its epidemiologic risk factors. We also incorporate emerging data from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) Program. PMID:16735783

  4. A dictionary in the dynamics of epidemiology.

    PubMed

    Antunes, José Leopoldo Ferreira

    2016-03-01

    This text synthesizes the impact of the book "A Dictionary of Epidemiology " in its two most recent editions (2008 and 2014). We related the reviews, discussions, and comments on the book in the specialized literature, as well as interventions of Miquel Porta, the editor of the publication, in the debate. We emphasized the importance of the dictionary in the dynamics of epidemiology as a source of bonding and debate for the professional environment, both before and after its publication. Finally, we offer suggestions on the new directions that may be taken in future editions of this volume.

  5. 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

  6. 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

  7. Against anti-health epidemiology: corporate obstruction of public health via manipulation of epidemiology.

    PubMed

    Egilman, David; Howe, Samantha

    2007-01-01

    In response to several articles on corporate corruption of science that appeared earlier in this journal, a critic outlined an epistemological model based on an unsupported assertion that epidemiologic evidence is always required to support cause-effect relationships. This model, if adopted, would eliminate compensation to victims of toxic exposures and impede regulation of accepted hazards. Epidemiology is only one element in support of cause-effect determinations. The critic's proposal of an anti-health epidemiology was initially developed by corporations with the goal of providing defense in litigation, and is based not on science but on a corporate need to enhance profits at the expense of public health.

  8. Time-dependent spectral analysis of epidemiological time-series with wavelets.

    PubMed

    Cazelles, Bernard; Chavez, Mario; Magny, Guillaume Constantin de; Guégan, Jean-Francois; Hales, Simon

    2007-08-22

    In the current context of global infectious disease risks, a better understanding of the dynamics of major epidemics is urgently needed. Time-series analysis has appeared as an interesting approach to explore the dynamics of numerous diseases. Classical time-series methods can only be used for stationary time-series (in which the statistical properties do not vary with time). However, epidemiological time-series are typically noisy, complex and strongly non-stationary. Given this specific nature, wavelet analysis appears particularly attractive because it is well suited to the analysis of non-stationary signals. Here, we review the basic properties of the wavelet approach as an appropriate and elegant method for time-series analysis in epidemiological studies. The wavelet decomposition offers several advantages that are discussed in this paper based on epidemiological examples. In particular, the wavelet approach permits analysis of transient relationships between two signals and is especially suitable for gradual change in force by exogenous variables.

  9. [Epidemiological aspects and methodological difficulties in establishing the causal relationship of Chernobyl nuclear accident with cancer].

    PubMed

    Ivan, A; Azoicăi, Doina

    2002-01-01

    The epidemiological, etiologic and clinical polymorphism of the morbid states, those accounted by radioactivity included, create major obstacles in the standardization of the methods for assessing the incidence of some diseases and their lethality. The many risk factors that can associate to radiations from various sources make the epidemiological data difficult to evaluate. The Chernobyl nuclear accident has revived the concerns and research in the field of prevention, early diagnosis and intervention of the effects of nuclear radiations by development of comparative, spatial and temporal, researches based on standardized methods, thus comparable results being provided. In Romania, the multidisciplinary epidemiological researches on the effects of Chernobyl accident upon health are still limited, and consequently insignificant for global conclusions.

  10. [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.

  11. Challenges in Dietary Exposure Assessment in Epidemiology: Research Trends.

    PubMed

    Ishihara, Junko

    2015-01-01

    Although exposure assessment of the usual diet is an essential component of nutrition epidemiology, it remains one of the most challenging issues in the field. Dietary exposure is widely measured using Food Frequency Questionnaires (FFQs), which impose a low burden on respondents and are inexpensive in large-scale studies. FFQs have long satisfied the needs of epidemiological research, and have helped deliver the tremendous recent growth in knowledge of the diet-disease association. However, issues surrounding measurement errors with FFQs have attracted substantial research interest around the world. Attenuation of the diet-disease association due to measurement errors identified in Western populations has led to extended methodological investigations comparing the performance of FFQs with biomarkers. The need for better dietary assessment methods has increased. Dietary records or recall provide relatively accurate estimates of intake for specific days, and of the usual diet if collected on multiple days. Until recently, however, their use in large-scale studies was not feasible, mainly due to cost. One innovative tool which may overcome the limitations of dietary records or recall is computerized 24-h dietary recall systems. These systems have been demonstrated to provide high-quality dietary intake data among Western populations. Incorporation of such new technology into large-scale epidemiological studies would make multiple-day administration of 24-h recall feasible in terms of cost. Research efforts to improve dietary assessment among Japanese and Asian populations are still under development. The development of innovative methods for Japanese remains an urgent research challenge. PMID:26598878

  12. 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.

  13. 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

  14. 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...

  15. Epidemiologic trends of sepsis in western countries

    PubMed Central

    Suarez De La Rica, Alejandro; Gilsanz, Fernando

    2016-01-01

    Since the American College of Chest Physicians (ACCP) and the Society of Critical care Medicine (SCCM) published the first consensus definition of syndromes related to sepsis in 1992, the knowledge of epidemiology of sepsis has clearly improved, although no prospective studies have been performed to analyse the incidence of sepsis in general population. There are differences in epidemiologic trends in sepsis between western countries and low-income and middle-income countries. In the United States (US), most of epidemiologic studies have been based on large, administrative databases, reporting an increase in the incidence of severe sepsis over years. In general, studies describing epidemiology of sepsis outside the US use clinical definitions and intensive care unit (ICU) observational cohort designs instead of administrative databases and definitions. Incidence of sepsis has increased over years, probably due to progressive aging of population, the existence of more comorbidities and maybe the liberal use of sepsis codification, by including patients with less severity. Notwithstanding, mortality due to sepsis is clearly decreasing over years, probably to improvement in ICU care, although absolute mortality is growing on account of the raise in incidence. Risk factors for sepsis are the two ends of life, male sex, US black race, presence of comorbidities and certain genetic variants. Respiratory tract infections are the most common source of sepsis, and, nowadays, Gram-positive infections are more frequent that Gram-negative sepsis in most prospective studies. PMID:27713883

  16. 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

  17. 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…

  18. Lessons from sea louse and salmon epidemiology.

    PubMed

    Groner, Maya L; Rogers, Luke A; Bateman, Andrew W; Connors, Brendan M; Frazer, L Neil; Godwin, Sean C; Krkošek, Martin; Lewis, Mark A; Peacock, Stephanie J; Rees, Erin E; Revie, Crawford W; Schlägel, Ulrike E

    2016-03-01

    Effective disease management can benefit from mathematical models that identify drivers of epidemiological change and guide decision-making. This is well illustrated in the host-parasite system of sea lice and salmon, which has been modelled extensively due to the economic costs associated with sea louse infections on salmon farms and the conservation concerns associated with sea louse infections on wild salmon. Consequently, a rich modelling literature devoted to sea louse and salmon epidemiology has been developed. We provide a synthesis of the mathematical and statistical models that have been used to study the epidemiology of sea lice and salmon. These studies span both conceptual and tactical models to quantify the effects of infections on host populations and communities, describe and predict patterns of transmission and dispersal, and guide evidence-based management of wild and farmed salmon. As aquaculture production continues to increase, advances made in modelling sea louse and salmon epidemiology should inform the sustainable management of marine resources. PMID:26880836

  19. 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…

  20. Ethnicity/race, ethics, and epidemiology.

    PubMed

    Whaley, Arthur L

    2003-08-01

    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.

  1. 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.

  2. Epidemiology, Health Literacy, and Health Education.

    ERIC Educational Resources Information Center

    Kaelin, Mark A.; Huebner, Wendy W.

    2002-01-01

    Presents a framework for teaching epidemiology to middle school students. The curriculum, "Detectives in the Classroom," addresses five essential questions: 'Why Are Some People Getting Sick While Others Remain Healthy?;''Is There an Association between the Hypothesized Cause and the Disease?;''Is This Association Causal?;''What Should Be Done…

  3. Chapter 1: Epidemiology of Type 1 Diabetes

    PubMed Central

    Maahs, David M; West, Nancy A; Lawrence, Jean M.; Mayer-Davis, Elizabeth J

    2010-01-01

    Synopsis This chapter describes the epidemiology of type 1 diabetes mellitus (T1D) around the world and across the lifespan. Epidemiologic patterns of T1D by demographic, geographic, biologic, cultural and other factors in populations are presented to gain insight about the etiology, natural history, risks, and complications of T1D. Data from large epidemiologic studies worldwide indicate that the incidence of T1D has been increasing by 2–5% worldwide and that the prevalence of T1D is approximately 1 in 300 in the US by 18 years of age. Research on risk factors for T1D is an active area of research to identify genetic and environmental triggers that could potentially be targeted for intervention. While significant advances have been made in the clinical care of T1D with resultant improvements in quality of life and clinical outcomes, much more needs to be done to improve care of, and ultimately find a cure for T1D. Epidemiologic studies have an important on-going role to investigate the complex causes, clinical care, prevention, and cure of T1D. PMID:20723815

  4. Infectious disease control in a long-term refugee camp: the role of epidemiologic surveillance and investigation.

    PubMed Central

    Elias, C J; Alexander, B H; Sokly, T

    1990-01-01

    This report demonstrates the role of epidemiologic surveillance and investigation in the control of infectious diseases in a long-term refugee camp. The applications of simple epidemiologic methods in a refugee camp on the Thai-Cambodian border are described for a one-year period. The development of a Health Information Office facilitated the collection of demographic and vital statistics data, administration of a disease surveillance system, regular monitoring of hospital and outpatient discharge diagnoses, and investigation of disease outbreaks. This office also organized community health education campaigns and disease control efforts. Examples of specific disease investigations are provided to demonstrate the utility of epidemiologic surveillance in the control of infectious disease. We conclude that simple epidemiologic methods play an important role in health planning in long-term refugee camps. PMID:2356906

  5. Q&A: Muin Khoury on cancer epidemiology.

    PubMed

    Khoury, Muin J; Rose, Suzanne

    2014-02-01

    Muin J. Khoury, MD, PhD, director of the Centers for Disease Control and Prevention's Office of Public Health Genomics and head of the National Cancer Institute's Epidemiology and Genomics Research Program in the Division of Cancer Control and Population Sciences, talks about challenges and opportunities in cancer epidemiology research and efforts in the epidemiology community to transform the field.

  6. Multivariate refutation of aetiological hypotheses in non-experimental epidemiology.

    PubMed

    Maclure, M

    1990-12-01

    Extension of Karl Popper's logic of refutation from the realm of contingency tables to multivariate modelling leads to the conclusion that rigorously scientific multivariate analysis in non-experimental epidemiology differs from the traditional quasi-scientific approach. Instead of aiming for high sensitivity in detecting aetiological agents, the goal in refutation is high specificity--to give the best defence of the 'innocence' of every exposure hypothesized as being a cause. Instead of 'forward selection' or 'backward elimination', multivariate refutation uses the method of 'forward elimination'. This entails a likelihood approach (which may be complemented by, but should be demarcated from, Bayesian methods) not only for statistical inference but also, by analogy, for study design and conduct: one starts with the conclusion (the estimate or hypothesis) and works backwards to the observations (the likelihood of the data or the design of the study). Differences in practice can sometimes be large, as illustrated by a study of hypothesized triggers of myocardial infarction. Multivariate refutation should replace the concept of multivariate modelling in non-experimental epidemiology.

  7. Using epidemiology and neurotoxicology to reduce risks to young workers.

    PubMed

    Rohlman, Diane S; Nuwayhid, Iman; Ismail, Ahmed; Saddik, Basema

    2012-08-01

    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.

  8. 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

  9. Using epidemiology and neurotoxicology to reduce risks to young workers.

    PubMed

    Rohlman, Diane S; Nuwayhid, Iman; Ismail, Ahmed; Saddik, Basema

    2012-08-01

    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

  10. [Scan statistic theory and its application in spatial epidemiology].

    PubMed

    Li, Xiu-yang; Chen, Kun

    2008-08-01

    To introduce the basic concept of scan statistic, its computation method and application in the area of spatial epidemiology. Retrospective space-time permutation statistics for evaluating the clustering of disease monitoring program is illustrated, using data on recent acute onset of cardiovascular disease in Hangzhou, China. Calculations were performed with SaTScan Version 7.0.3. With 999 Monte Carlo replications, the program took 5 seconds to run on a 100-MHz Pentium PC. The geographical surveillance program on acute onset clusters of cardiovascular disease, data which showed statistical significance, would include: a) from January 1, 1997 to February 28, 2007 in Qiantan township, Jiande county (P = 0.001); b) highly significant between January 1, 1997 and February 28, 1999 for Lushan street, Lingqiao township in Fuyang county (P = 0.003); c) between March 1, 2001 and February 29, 2004 for Dayuan town, Xinyi town, Shouxiang town in Fuyang (P = 0.004); d) between March 1, 2004 and Feb 28, 2006 for Chengzhan street, Ziyang street, Hubin street, Qinbo street, Xiaoying street, Wangjiang street, Chaoming street, Changqing street, Wulin street, Tianshui street, Wenhui street and Shiqiao street in Hangzhou (P = 0.005), respectively. The retrospective space-time permutation statistics seems useful as a screening tool for identifying the cluster of disease. Scan statistics are practical and effective method for deciding which cluster alarms would merit further investigation and which clusters are probably chance occurrences in the study of spatial epidemiology. PMID:19103124

  11. 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. PMID:21511849

  12. 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

  13. 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

  14. 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.

  15. 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

  16. Epidemiological Surveillance of Lymphocryptovirus Infection in Wild Bonobos.

    PubMed

    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

  17. 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.

  18. Shared dosimetry error in epidemiological dose-response analyses

    DOE PAGES

    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 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

  19. 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

  20. 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