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Syndrome Epidemic (syndrome + epidemic)
Selected AbstractsEffect of Small-World Networks on Epidemic Propagation and InterventionGEOGRAPHICAL ANALYSIS, Issue 3 2009Zengwang Xu The small-world network, characterized by special structural properties of high connectivity and clustering, is one of the highlights in recent advances in network science and has the potential to model a variety of social contact networks. In an attempt to better understand how these structural properties of small-world networks affect epidemic propagation and intervention, this article uses an agent-based approach to investigate the interplay between an epidemic process and its underlying network structure. Small-world networks are derived from a network "rewiring" process, which readjusts edges in a completely regular two-dimensional network by different rewiring probabilities (0,1) to produce a spectrum of modified networks on which an agent-based simulation of epidemic propagation can be conducted. A comparison of simulated epidemics discloses the effect of small-world networks on epidemic propagation as well as the effectiveness of different intervention strategies, including mass vaccination, acquaintance vaccination, targeted vaccination, and contact tracing. Epidemics taking place on small-world networks tend to reach large-scale epidemic peaks within a short time period. Among the four intervention strategies tested, only one strategy,the targeted vaccination,proves to be effective for containing epidemics, a finding supported by a simulation of the severe acute respiratory syndrome epidemic in a large-scale realistic social contact network in Portland, OR. Las redes de mundo de pequeño (,small-world networks'), caracterizadas por sus propiedades estructurales especiales de alta conectividad y aglomeración (,clustering') son uno de los ejemplos más destacados de los avances más recientes de la ciencia de redes, y tiene el potencial de modelar una gran variedad de redes sociales de contacto. En un intento de comprender mejor como estas propiedades estructurales de redes ,small-world' afectan la propagación e intervención de epidemias, el estudio presente emplea un enfoque basado en modelos multi-agente (,agent based') para investigar la interacción entre el proceso epidémico y la estructura de redes en la que estan integrados. Las redes de mundo pequeño se derivan del proceso de recableado (,rewiring') el cual reajusta los límites en una red 2-D de acuerdo a varias probabilidades de reconexión (0-1) para producir un abanico de posibles de redes modificadas sobre los cuales se condujo una simulación multi-agente de la propagación de la epidemia. El efecto de las redes ,small world' y de las diferentes estrategias de intervención (por ejemplo, diferentes estrategias de vacunación) son evidenciadas mediante la comparación entre varias simulaciones de la epidemia. Las epidemias que ocurren en redes de tipo ,small-world' tienden a alcanzar picos de gran escala epidémica en un corto periodo de tiempo. Entre las estrategias evaluadas, sólo una ,vacunación dirigida a una población objetivo (,targeted vaccination')- demostró ser efectiva en la contención de la epidemia. Dicho resultado se obtuvo vía la simulación de la epidemia de SRAS (Síndrome Respiratorio Agudo Severo ,SARS') realiada en Portland, Oregon (EEUU). [source] An evaluation of nursing practice models in the context of the severe acute respiratory syndrome epidemic in Hong Kong: a preliminary studyJOURNAL OF CLINICAL NURSING, Issue 6 2006Engle Angela Chan PhD Aim and objective., Like other health-care workers, Hong Kong nurses had their professional knowledge and skills seriously challenged during the SARS outbreak. Could current nursing practices support the care of SARS or SARS-like patients in the future? If not, alternative practices would be needed. Providing a preliminary understanding, this paper compares the conventional with different nursing delivery models in a simulated SARS ward and focuses on nurses' efficiency, infection control practices and views of the two models. Design and methods., This study was conducted in three phases. First, a baseline understanding of nursing practices was achieved through four workflow observations. In an eight-hour day, four research assistants observed nursing activities in the medical and fever wards. These data were used in the second phase to construct two sets of clinical vignettes, pertaining to SARS patient care in both conventional and alternative practice models. These scripts were discussed with nine nurses of various ranks from the hospital under study for their expert validation and input. In the third phase, nurse participants and patient actors enacted the vignettes in a simulated setting. Video-taped observations and four nurse participant interviews were employed. Observational data were analysed through descriptive statistics and independent t -tests. Textual data were coded and categorized for common meanings. Results., Conventional practice from the findings consisted of cubicle and named nurse nursing. While the former reflected modified team and functional nursing, it did not confine patient care within a cubicle as suggested by its name. The latter depicted a modified primary nursing approach in a team, with delegation of care. Preliminary findings concerning infection control and nurse satisfaction revealed that the alternative model had an advantage over the conventional. Relevance to clinical practice., This study findings lay the foundation for clinical trials, which would evaluate the significance of patient-care quality, cost-effectiveness and better human resource management by restructuring current nursing practices. [source] SIRT6 protects against pathological damage caused by diet-induced obesityAGING CELL, Issue 2 2010Yariv Kanfi Summary The NAD+-dependent SIRT6 deacetylase is a therapeutic candidate against the emerging metabolic syndrome epidemic. SIRT6, whose deficiency in mice results in premature aging phenotypes and metabolic defects, was implicated in a calorie restriction response that showed an opposite set of phenotypes from the metabolic syndrome. To explore the role of SIRT6 in metabolic stress, wild type and transgenic (TG) mice overexpressing SIRT6 were fed a high fat diet. In comparison to their wild-type littermates, SIRT6 TG mice accumulated significantly less visceral fat, LDL-cholesterol, and triglycerides. TG mice displayed enhanced glucose tolerance along with increased glucose-stimulated insulin secretion. Gene expression analysis of adipose tissue revealed that the positive effect of SIRT6 overexpression is associated with down regulation of a selective set of peroxisome proliferator-activated receptor-responsive genes, and genes associated with lipid storage, such as angiopoietin-like protein 4, adipocyte fatty acid-binding protein, and diacylglycerol acyltransferase 1, which were suggested as potential targets for drugs to control metabolic syndrome. These results demonstrate a protective role for SIRT6 against the metabolic consequences of diet-induced obesity and suggest a potentially beneficial effect of SIRT6 activation on age-related metabolic diseases. [source] Estimates of human immunodeficiency virus prevalence and proportion diagnosed based on Bayesian multiparameter synthesis of surveillance dataJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 3 2008A. Goubar Summary., Estimates of the number of prevalent human immunodeficiency virus infections are used in England and Wales to monitor development of the human immunodeficiency virus,acquired immune deficiency syndrome epidemic and for planning purposes. The population is split into risk groups, and estimates of risk group size and of risk group prevalence and diagnosis rates are combined to derive estimates of the number of undiagnosed infections and of the overall number of infected individuals. In traditional approaches, each risk group size, prevalence or diagnosis rate parameter must be informed by just one summary statistic. Yet a rich array of surveillance and other data is available, providing information on parameters and on functions of parameters, and raising the possibility of inconsistency between sources of evidence in some parts of the parameter space. We develop a Bayesian framework for synthesis of surveillance and other information, implemented through Markov chain Monte Carlo methods. The sources of data are found to be inconsistent under their accepted interpretation, but the inconsistencies can be resolved by introducing additional ,bias adjustment' parameters. The best-fitting model incorporates a hierarchical structure to spread information more evenly over the parameter space. We suggest that multiparameter evidence synthesis opens new avenues in epidemiology based on the coherent summary of available data, assessment of consistency and bias modelling. [source] Psychosocial impact among the public of the severe acute respiratory syndrome epidemic in TaiwanPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2006CHIH-HUNG KO md Abstract, During the 2003 outbreak, severe acute respiratory syndrome (SARS) spread to more than 30 countries. Not only did it cause severe health problems but it also imposed a great psychological impact on the public. SARS emerged in Taiwan during April 2003. This study investigates the psychosocial impact and the associated factors of depression of the SARS epidemic in Taiwan when the epidemic had just been controlled. A total of 1552 respondents were recruited in the study by random selection from the telephone book. Demographic data, SARS experience, self-perceived health state, neighborhood relationships, and depression were surveyed by telephone interviewing. Respondents were grouped as ,impacted group' and ,non-impacted group' according to whether they or their friends and family had been quarantined, or suspected of being infected. The psychosocial impact and associated factors were compared between the two groups. The ,impacted group' had higher depressive levels, poorer neighborhood relationships, poorer self-perceived health, and a higher economic impact than the ,non-impacted group'. The poorer self-perceived health and economic impact factors were associated with depression. The neighborhood relationship factor was negatively associated with depression for the ,impacted group', but not for the ,non-impacted group'. The ,impacted group' had experienced greater psychosocial impact possibly due to the SARS impact, the economic downturn, poor self-perceived health conditions, and decreased social support systems. An appropriate mental health intervention to improve the self-perceived health condition, to provide instrumental and psychological support for the ,impacted group', and to decrease the stigmatization and discrimination from the public could have buffered the psychological impact from this epidemic disaster. [source] | ||||||||||