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The real-time evaluation of the effectiveness of vaccination campaigns at the population level is essential for public health policy makers and scientists working toward successful mitigation of the COVID-19 pandemic. [...]

West Nile virus (WNV) is one of the most widespread of the arboviruses because of the translocation of the virus by migratory birds (2-3). Since its initial detection in Uganda [...]

Introduction: Misclassification of HIV deaths can substantially diminish the usefulness of cause of death data for decisionmaking. In this study, we describe the methods developed by the Global Burden of Disease Study to account for the misclassified cause of death data from vital registration systems for estimating HIV mortality in 132 countries and territories. Methods: The cause of death data were obtained from the World Health Organization Mortality Database and official country-specific mortality databases. We implemented two steps to adjust the raw cause of death data: (1) redistributing garbage codes to underlying causes of death, including HIV/AIDS by applying methods, such as analysis of multiple cause data and proportional redistribution, and (2) reassigning HIV deaths misclassified as other causes to HIV/AIDS by examining the age patterns of underlying causes in location and years with and without HIV epidemics. Results: In 132 countries, during the period from 1990 to 2018, 1,848,761 deaths were reported as caused by HIV/AIDS. After garbage code redistribution in these 132 countries, this number increased to 4,165,015 deaths. An additional 1,944,291 deaths were added through correction of HIV deaths misclassified as other causes in 44 countries. The proportion of HIV deaths derived from garbage code redistribution decreased over time, from 0.4 in 1990 to 0.1 in 2018. The proportion of deaths derived from HIV misclassification correction peaked at 0.4 in 2006 and declined afterwards to 0.08 in 2018. The greatest contributors to garbage code redistribution were 'immunodeficiency antibody' (ICD 9: 279-279.1; ICD 10: D80-D80.9) and 'immunodeficiency other' (ICD 9: 279, 279.5-279.9; ICD 10: D83-D84.9, D89, D89.8-D89.9), which together contributed 77% of all redistributed deaths at their peak in 1995. Respiratory tuberculosis (ICD 9: 010-012.9; ICD 10: A10-A14, A15-A16.9) contributed the greatest proportion of all HIV misclassified deaths (25-62% per year) over the most years. Conclusions: Correcting for miscoding and misclassification of cause of death data can enhance the utility of the data for analyzing trends in HIV mortality and tracking progress toward the Sustainable Development Goal targets. Keywords: cause of death; garbage coding; HIV mortality; misclassification, 1 | INTRODUCTION Accurate measurement of mortality and causes of death is an essential basis of policy planning and prioritizing interventions. To facilitate systematic recording and comparison of morbidity and [...]

Mathematical transmission models are useful tools for predicting the magnitude, duration, and severity of the severe acute respiratory coronavirus 2 (SARS-CoV-2) pandemic. However, widely used national-level models might not capture [...]

In late December 2019, a cluster of cases of pneumonia of unknown etiology were reported linked to a market in Wuhan, China.sup.1. The causative agent was identified as the species Severe acute respiratory syndrome-related coronavirus and was named SARS-CoV-2 (ref. .sup.2). By 16 April the virus had spread to 185 different countries, infected over 2,000,000 people and resulted in over 130,000 deaths.sup.3. In the Netherlands, the first case of SARS-CoV-2 was notified on 27 February. The outbreak started with several different introductory events from Italy, Austria, Germany and France followed by local amplification in, and later also outside, the south of the Netherlands. The combination of near to real-time whole-genome sequence analysis and epidemiology resulted in reliable assessments of the extent of SARS-CoV-2 transmission in the community, facilitating early decision-making to control local transmission of SARS-CoV-2 in the Netherlands. We demonstrate how these data were generated and analyzed, and how SARS-CoV-2 whole-genome sequencing, in combination with epidemiological data, was used to inform public health decision-making in the Netherlands. The combination of near to real-time whole-genome sequence analysis and epidemiology resulted in reliable assessments of the extent of SARS-CoV-2 transmission in the community, facilitating early decision-making to control local transmission of SARS-CoV-2 in the Netherlands., Author(s): Bas B. Oude Munnink [sup.1] , David F. Nieuwenhuijse [sup.1] , Mart Stein [sup.2] , Áine O'Toole [sup.3] , Manon Haverkate [sup.2] , Madelief Mollers [sup.2] , Sandra K. [...]

Author(s): Ajit Lalvani 1,2,*, Luis C. Berrocal-Almanza 1, Alice Halliday 2,3 Current tools are not fit for purpose to deliver tuberculosis elimination Tuberculosis (TB) is the leading cause of mortality [...]

The COVID-19 pandemic has highlighted the crucial importance of antibody surveys in estimating the incidence of SARS-CoV-2 infection at a population level. Studies in Brazil and China address the use of serology to obtain a better estimate of the infection rate., Author(s): Marion Koopmans [sup.1] , Bart Haagmans [sup.1] Author Affiliations: (1) Viroscience Department, Erasmus MC, Rotterdam, the Netherlands Estimates of the spread of the coronavirus SARS-CoV-2 and the severity of [...]

Abstract In the aftermath of any natural disaster, a quick assessment of economic damage is called for, without which recovery planning and fiscal budgeting is impossible. What is customarily done [...]

The article examines the impact of genetic self-knowledge on the research process and its implications for confounding and ascertainment bias. It proposes some study designs and analytic methods for research and considers the potential impact of personalized genetics in epidemiological research in general.

Many important questions and theories in demography focus on changes over time, and on how those changes differ over geographic and social space. Space-time analysis has always been important in studying fertility transitions, for example. However, demographers have seldom used formal statistical methods to describe and analyze time series of maps. One formal method, used widely in epidemiology, criminology, and public health, is Knox's space-time interaction test. In this article, we discuss the potential of the Knox test in demographic research and note some possible pitfalls. We demonstrate how to use familiar proportional hazards models to adapt the Knox test for demographic applications. These adaptations allow for nonrepeatable events and for the incorporation of structural variables that change in space and time. We apply the modified test to data on the onset of fertility decline in Brazil over 1960-2000 and show how the modified method can produce maps indicating where and when diffusion effects seem strongest, net of covariate effects.

OBJECTIVE: To provide a contemporary profile of epidemiological trends of infective endocarditis (IE) in Olmsted County, Minnesota. PATIENTS AND METHODS: This study consists of all definite or possible IE cases [...]

The 2009 H1N1 swine flu is the first influenza pandemic in decades. The crystal structure of the hemagglutinin from the A/California/04/2009 H1N1 virus shows that its antigenic structure, particularly within the Sa antigenic site, is extreme[y similar to those of human H1N1 viruses circulating early in the 20th century. The cocrystal structure of the 1918 hemagglutinin with 2D1, an antibody from a survivor of the 1918 Spanish flu that neutralizes both 1918 and 2009 H1N1 viruses, reveals an epitope that is conserved in both pandemic viruses. Thus, antigenic similarity between the 2009 and 1918-like viruses provides an explanation for the age-related immunity to the current influenza pandemic. 10.1126/science.1186430

The linkage of Kaposi sarcoma (KS) to infection by a novel human herpesvirus (Kaposi sarcoma-associated herpesvirus [KSHV]) is one of the great successes of contemporary biomedical research and was achieved by using advanced genomic technologies in a manner informed by a nuanced understanding of epidemiology and clinical investigation. Ongoing efforts to understand the molecular mechanisms by which KSHV infection predisposes to KS continue to be powerfully influenced by insights emanating from the clinic. Here, recent developments in KS pathogenesis are reviewed, with particular emphasis on clinical, pathologic, and molecular observations that highlight the many differences between this process and tumorigenesis by other oncogenic viruses., It is now 15 years since the discovery by Yuan Chang, Patrick Moore, and their colleagues (1) of DNA from a novel herpesvirus in biopsy specimens of human Kaposi sarcoma [...]

Purpose: To determine risk and protective factors for speech and language impairment in early childhood. Method: Data are presented for a nationally representative sample of 4,983 children participating in the Longitudinal Study of Australian Children (described in McLeod & Harrison, 2009). Thirty-one child, parent, family, and community factors previously reported as being predictors of speech and language impairment were tested as predictors of (a) parent-rated expressive speech/language concern and (b) receptive language concern, (c) use of speech-language pathology services, and (d) low receptive vocabulary. Results: Bivariate logistic regression analyses confirmed 29 of the identified factors. However, when tested concurrently with other predictors in multivariate analyses, only 19 remained significant: 9 for 2-4 outcomes and 10 for 1 outcome. Consistent risk factors were being male, having ongoing hearing problems, and having a more reactive temperament. Protective factors were having a more persistent and sociable temperament and higher levels of maternal well-being. Results differed by outcome for having an older sibling, parents speaking a language other than English, and parental support for children's learning at home. Conclusion: Identification of children requiring speech and language assessment requires consideration of the context of family life as well as biological and psychosocial factors intrinsic to the child. KEY WORDS: risk factor, protective factor, epidemiology, speech, language, communication, Speech and language acquisition in early childhood is a powerful indicator of the developmental and cognitive abilities that underpin children's successful transition to school (Nelson, Nygren, Walker, & Panoscha, 2006). [...]

Objective: Few studies have explored the topography of antisocial behavior in a nationally representative sample of inhalant users. We examined (a) the lifetime prevalence of 20 childhood and adult antisocial behaviors in inhalant users with inhalant-use disorders (IUD+) and without IUDs (IUD-); (b) the nature and strength of associations between inhalant use, IUDs, and specific antisocial behaviors in multivariate analyses; and (c) the relationships between inhalant use, IUDs, and antisocial behaviors in a national sample of adults with antisocial personality disorder. Method: The National Epidemiologic Survey on Alcohol and Related Conditions was a multistage national survey of 43,093 U.S. residents. Respondents completed a structured psychiatric interview. Results: IUD+ and IUD- respondents were significantly younger and more likely to be unemployed, to be male, to have never married, and to report family and personal histories of alcohol and drug problems than inhalant nonusers. Family histories of alcohol problems and personal histories of drug problems were significantly more prevalent among IUD+ respondents, compared with IUD- respondents. In bivariate analyses, IUD+ and IUD- respondents evidenced significantly higher lifetime levels of all childhood and adult antisocial behaviors than inhalant nonusers. IUD+ respondents were significantly more likely than their IUD- counterparts to report bullying behavior, starting physical fights, using dangerous weapons, physical cruelty to people, staying out all night without permission, running away, and frequent truancy in childhood, as well as greater deceitfulness, impulsivity, irritability/aggressiveness, recklessness, and irresponsibility in adulthood. Multivariate analyses indicated that IUD+ respondents had a significantly elevated risk for childhood and adult antisocial behaviors, compared with inhalant nonusers, with the strongest effects for using dangerous weapons, physical cruelty to animals, and physical cruelty to people. Similarly, IUD+ respondents differed significantly from their IUD- counterparts primarily across measures of interpersonal violence. Among persons with antisocial personality disorder, inhalant use and IUDs were associated with greater antisocial behavior, albeit with fewer and weaker effects. Conclusions: Respondents with IUDs had pervasively elevated levels of antisocial conduct, including diverse forms of early-onset and interpersonally violent behavior. (J. Stud. Alcohol Drugs, 71, 201-209, 2010), CRIMINOLOGICAL AND CLINICAL STUDIES suggest that adolescent and adult inhalant users are disproportionately involved in antisocial acts. Howard et al. (2008) found that 36.7% of 723 youths in residential treatment [...]

Several simulations are conducted to explain the impact of the various uncertainties observed in population incidence rates and genotype frequencies on the lifetime risk estimates of different populations. The significance of the different epidemiologic parameters in estimating the risk estimates in personal genomic profiles is also demonstrated.

The study discusses the differences in the prevalence of attention-deficit/hyperactivity disorder (ADHD) among Puerto Rican children and the influence of risk factors on mental health services, medication and psychostimulant use among them in two different contexts. The conclusion states that prevalence was similar regardless of context and receiving mental health services and medication including psychostimulants would depend on the differences in the levels of associated risks.

Collection of dietary intake in epidemiologic studies involves using methods that are comprehensive yet appropriate for the population being studied. Here we describe a diet history questionnaire (DHQ) that was developed using an audio self-administered computer-assisted interview technique. The DHQ was developed for use in a cohort of American Indians and Alaskan Natives with tribal input and area-specific modules to incorporate local food availability. The DHQ includes 54 main food group questions, specific food items within the main food group, and food preparation and general eating practice questions. The questionnaire was programmed to be self-administered using a computer with a touch screen. The average time for the first 6,604 participants to complete the questionnaire was 36 minutes. Almost 100% of participants had complete DHQ data and the average number of food items selected was 70. The methods developed for collection of dietary data appear to be appropriate for the targeted population and may have usefulness for other populations where collecting dietary data in a self-administered format is desirable.

Abstract Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalizability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative developed recommendations on what should be included in an accurate and complete report of an observational study. We defined the scope of the recommendations to cover three main study designs: cohort, case-control and cross- sectional studies. We convened a two-day workshop, in September 2004, with methodologists, researchers and journal editors to draft a checklist of items. This list was subsequently revised during several meetings of the coordinating group and in e-mail discussions with the larger group of STROBE contributors, taking into account empirical evidence and methodological considerations. The workshop and the subsequent iterative process of consultation and revision resulted in a checklist of 22 items (the STROBE Statement) that relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to all three study designs and four are specific for cohort, case-control, or cross-sectional studies. A detailed Explanation and Elaboration document is published separately and is freely available on the web sites of PLoS Medicine, Annals of Internal Medicine and Epidemiology. We hope that the STROBE Statement will contribute to improving the quality of reporting of observational studies. Resume Les recherches menees dans le domaine biomedical sont pour une grande part de nature observationnelle. Les rapports de ces etudes sont souvent inadequats, ce qui empeche l'evaluation des points forts et des defauts de l'etude et sa generalisation. L'Initiative STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) a elabore des recommandations sur ce que doit etre le contenu d'un rapport complet et precis d'etude observationnelle. Nous avons defini le champ d'application de ces recommandations comme couvrant les trois principaux types d'etude, a savoir les etudes de cohorte, cas-temoins et transversales. En septembre 2004, dans le cadre d'un atelier de deux jours, nous avons invite des methodologistes, des chercheurs et des editeurs de revue a elaborer une liste de points a considerer. Cette liste a ensuite ete revisee dans le cadre de plusieurs reunions du groupe coordinateur et de discussions par courrier electronique avec le groupe plus large des contributeurs a l'Initiative STROBE, en tenant compte de resultats empiriques et de considerations methodologiques. L'atelier et le processus iteratif ulterieur de consultation et de revision ont debouche sur une liste de controle en 22 points (la declaration STROBE) concernant le titre, le resume, l'introduction, la methodologie et les parties Resultats et Discussion des articles. Dix-huit points s'appliquent collectivement aux trois types d'etude et quatre specifiquement aux etudes de cohortes, cas-temoins ou transversales. Un document intitule Explanation and Elaboration est publie separement et accessible gratuitement sur les sites Internet PloS Medicine, Annals of lnternal Medicine et Epidemiology. Nous esperons que la declaration STROBE contribuera a l'amelioration de la qualite des rapports d'etude observationnelle. Une traduction en francais de ce resume figure a la fin de l'article. Resumen Gran parte de la investigacion biomedica es de tipo observacional, pero la informacion difundida sobre esas investigaciones es a menudo insuficiente, Io que dificulta la evaluacion de sus puntos fuertes y debiles y de su generalizabilidad de las conclusiones. En el marco de la iniciativa de Fortalecimiento de la Notificacion de los Estudios Observacionales en Epidemiologia (STROBE), se formularon recomendaciones sobre lo que deberia contener una notificacion precisa de un estudio observacional. Decidimos limitar el alcance de las recomendaciones a tres grandes modalidades de estudio: estudios de cohortes, estudios de casos y controles, y estudios transversales. En septiembre de 2004 organizamos un taller de dos dias con metodologos, investigadores y editores de revistas para elaborar una lista de verificacion de distintos puntos. Esta lista fue revisada posteriormente en varias reuniones del grupo de coordinacion y en discusiones mantenidas por e-mail con los principales participantes en STROBE, teniendo en cuenta la evidencia empirica y diversas consideraciones metodologicas. El taller y el posterior proceso iterativo de consulta y revision desembocaron en una lista de verificacion de 22 puntos (la declaracion STROBE) que guardan relacion con el titulo, el resumen, la introduccion y las secciones de metodos, resultados y discusion de los articulos. Dieciocho puntos son comunes a las tres modalidades de estudio, y cuatro se refieren especificamente a los estudios de cohortes, de casos y controles o transversales. Se ha publicado separadamente un documento de Explicacion y elaboracion al que puede accederse libremente en los sitios web de PLoS Medicine, Annals of Internal Medicine y Epidemiology. Esperamos que la declaracion STROBE contribuya a mejorar la calidad de la notificacion de los estudios observacionales. Al final del articulo se facilita una traduccion al espanol. [TEXT NOT REPRODUCIBLE IN ASCII.], Introduction Many questions in medical research are investigated in observational studies. (1) Much of the research into the cause of diseases relies on cohort, case-control or cross-sectional studies. Observational studies [...]

Background Epidemiological studies may be subject to selective reporting, but empirical evidence thereof is limited. We empirically evaluated the extent of selection of significant results and large effect sizes in [...]

The estimation of tobacco-reporting validity in an epidemiological survey on drug use was carried out by comparing the responses to questions about tobacco use and passive exposure to smoking with biological tests for cotinine. The underreporting of tobacco was relatively rare but the estimates of the study state that it may be increasing over time.

The recruitment and baseline epidemiologic characteristics of volunteers in the first phase 3 placebo-controlled trial of a recombinant gp 120HIV vaccine is described. The men and women at high risk for sexually transmitted HIV infection were successfully recruited for the first phase 3 HIV vaccine efficacy trial.

Byline: Tjeerd-Pieter Staa (1,2,3), Nick Bishop (4), Hubert G. M. Leufkens (2), Cyrus Cooper (1) Keywords: Asthma; Children; Epidemiology; Osteoporosis Abstract: Inhaled corticosteroids are widely used in the long-term management of asthma in children. Data on the relationship between inhaled corticosteroid therapy and osteoporotic fracture are inconsistent. We address this issue in a large population-based cohort of children aged 4--17 years in the UK (the General Practice Research Database). The incidence rates of fracture among children aged 4--17 years taking inhaled corticosteroids (n=97,387), taking bronchodilators only (n=70 984) and a reference group (n=345,758) were estimated. Each child with a non-vertebral fracture (n=23,984) was subsequently matched by age, sex, practice, and calendar time to one child without a fracture. Fracture incidence was increased in children using inhaled corticosteroids, as well as in those receiving bronchodilators alone. With an average daily beclomethasone dose of 200 ug or less, the crude fracture risk relative to nonusers was 1.10 [95% confidence interval (CI), 0.96--1.26] with dosage of 201--400 ug, it was 1.23 (95% CI, 1.08--1.39) and with dosages over 400 ug, it was 1.36 (95% CI, 1.11--1.67). This excess risk disappeared after adjustment for indicators of asthma severity. The increased risk of fracture associated with use of inhaled corticosteroids is likely to be the result of the underlying illness, rather than being directly attributable to inhaled corticosteroid therapy. Author Affiliation: (1) MRC Epidemiology Resource Centre, University of Southampton, Southampton, SO16 6YD, UK (2) Department of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute for Pharmaceutical Sciences, Sorbonnelaan 16, Utrecht, The Netherlands (3) Procter &amp Gamble Pharmaceuticals, Rusham Park, Egham, UK (4) Academic Child Health, Sheffield University, Sheffield, UK Article History: Registration Date: 27/01/2004 Received Date: 08/12/2003 Accepted Date: 26/01/2004 Online Date: 21/02/2004

Byline: Jorge Morales-Torres (1,3), Sergio Gutierrez-Urena (2) Keywords: Burden of Illness; Epidemiology; Osteoporosis; Osteoporotic fractures Abstract: Osteoporosis causes considerable morbidity, mortality and resource utilization in industrialized nations. Its burden is relatively well known in United States and Canada, but poorly studied in the rest of America. This study aimed to discover the burden of osteoporosis in Latin America through a review of literature and publicly available information. In this transversal and descriptive study, information from 20 countries in Latin American region was collected from diverse published and electronic sources. Rheumatologists and bone specialists were asked for additional information through a questionnaire created by consensus. In the year 2000, the population of the Latin America and Caribbean region was 524 million from diverse ethnic origins. On average, 5.5% of the population is 65 years and older. However, with life expectancy higher than 70 years in most countries, a significant growth in the elderly population is anticipated. Studies using World Health Organization's criteria for osteoporosis report 12--18% of women 50 years and older with vertebral osteoporosis and 8--22% with proximal femur osteoporosis. Community based studies in Argentina reported between 263 and 331 hip fractures per 100,000 people 50 years and older. Hospital based studies in Colombia, Chile, Brazil, Mexico, Panama, Peru and Venezuela reported between 40 and 362 hip fractures per 100,000 persons aged 50 and more. Between 17 and 37% of hip fracture sufferers die in the year following fracture. Prevalence of vertebral fractures in community-dwelling women aged 50 and more in Mexico is 19.35%. Data on other fractures are rare. Direct costs of a hip fracture ranged from $4500 to $6000. National gross income per capita in the region ranges from $410 to $7550. The burden of osteoporosis varies across countries with differences in populations and health resources. Considerable support for research is required, since numerous gaps in knowledge need to be filled to face the anticipated explosive growth in osteoporotic fractures. Author Affiliation: (1) Osteoporosis Unit, Hospital Aranda de la Parra, Leon, Gto, Mexico (2) Department of Rheumatology, Hospital Civil de Guadalajara 'Fray Antonio Alcalde'. URHIA, CUCS, Universidad de Guadalajara, Guadalajara, Jal, Mexico (3) Privada Florencia 107, Col. Andrade, 37370, Leon, Gto, Mexico Article History: Registration Date: 19/01/2004 Received Date: 14/09/2003 Accepted Date: 06/01/2004 Online Date: 20/03/2004 Article note: This study was performed under the auspices of the World Health Organization Collaborative Center, Liege, Belgium

* Objectives.--To review the state of the art relating to protein S deficiency as a risk factor for thrombosis and to make recommendations regarding the use of protein S measurements in the assessment of thrombotic risk in individual patients and families. Data Sources, Extraction, and Synthesis.--Selection criteria were developed for the inclusion of publications from 1985 to 2001 based on the relevant literature concerned with the systematic review of diagnostic tests. Minimal selection criteria were agreed on and the articles stratified into level 1 if they met these criteria and level 2 if they did not meet these criteria. The included articles were reviewed by the authors and abstracted onto predetermined data collection forms. These forms were then scored and recommendations based on level 1 studies. As described elsewhere, results of discussions at the College of American Pathologists Conference XXXVI on Diagnostic Issues in Thrombophilia were used to revise the manuscript into its final form. Conclusions.--Consensus was reached on 16 recommendations for the use of protein S assays in the assessment of thrombotic risk in individuals and families. Two themes run through the conclusions. First, protein S assays are the most technically problematic of the assays reviewed at this conference. Second, only 2 papers evaluating the diagnostic use of protein S assays met our level 1 inclusion criteria. These 2 problems point out the need for better standardized assays and rigorous studies of the diagnostic utility of these assays., This article examines the technical and diagnostic aspects of protein S (PS) assays and their application to clinical epidemiologic studies. The PS anticoagulant system is complex both in the measurement [...]

Byline: A. A. Ismail (1), S. R. Pye (1), W. C. Cockerill (1), M. Lunt (1), A. J. Silman* (1), J. Reeve* (2), D. Banzer (3), L. I. Benevolenskaya (4), A. Bhalla (5), J. Bruges Armas (6), J. B. Cannata (7), C. Cooper (8), P. D. Delmas (9), J. Dequeker (10), G. Dilsen (11), J. A. Falch (12), B. Felsch (13), D. Felsenberg (14), J. D. Finn (1), C. Gennari (15), K. Hoszowski (16), I. Jajic (17), J. Janott (18), O. Johnell (19), J. A. Kanis (20), G. Kragl (21), A. Lopez Vaz (22), R. Lorenc (23), G. Lyritis (24), F. Marchand (25), P. Masaryk (26), C. Matthis (27), T. Miazgowski (28), M. Naves-Diaz (7), H. A. P. Pols (29), G. Poor (30), A. Rapado (31), H. H. Raspe (27), D. M. Reid (32), W. Reisinger (33), C. Scheidt-Nave (34), J. Stepan (35), C. Todd (36), K. Weber (37), A. D. Woolf (38), T. W. O'Neill (1) Keywords: Key words:Epidemiology -- Europe -- Incidence -- Limb fracture -- Osteoporosis Abstract: The aim of this population-based prospective study was to determine the incidence of limb fracture by site and gender in different regions of Europe. Men and women aged 50--79 years were recruited from population registers in 31 European centers. Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. Subjects were subsequently followed up using an annual postal questionnaire which included questions concerning the occurrence of new fractures. Self-reported fractures were confirmed where possible by radiograph, attending physician or subject interview. There were 6451 men and 6936 women followed for a median of 3.0 years. During this time there were 140 incident limb fractures in men and 391 in women. The age-adjusted incidence of any limb fracture was 7.3/1000 person-years [pyrs] in men and 19 per 1000 pyrs in women, equivalent to a 2.5 times excess in women. Among women, the incidence of hip, humerus and distal forearm fracture, though not 'other' limb fracture, increased with age, while in men only the incidence of hip and humerus fracture increased with age. Among women, there was evidence of significant variation in the occurrence of hip, distal forearm and humerus fractures across Europe, with incidence rates higher in Scandinavia than in other European regions, though for distal forearm fracture the incidence in east Europe was similar to that observed in Scandinavia. Among men, there was no evidence of significant geographic variation in the occurrence of these fractures. This is the first large population-based study to characterize the incidence of limb fracture in men and women over 50 years of age across Europe. There are substantial differences in the descriptive epidemiology of limb fracture by region and gender. Author Affiliation: (1) ARC Epidemiology Unit, University of Manchester, Manchester, UK, GB (2) Strangeways Research Laboratories, Cambridge, UK, GB (3) Behring Hospital, Berlin, Germany, DE (4) Institute of Rheumatology, Moscow, Russia, RU (5) Royal National Hospital for Rheumatic Diseases, Bath, UK, GB (6) Hospital de Angra do Heroismo, Azores, Portugal, PT (7) Asturia General Hospital, Oviedo, Spain, ES (8) University of Southampton, Southampton General Hospital, Southampton, UK, GB (9) U. INSERM 403, Lyon, France, FR (10) University Hospital, Leuven, Belgium, BE (11) Medical Faculty, University of Istanbul, Istanbul, Turkey, TR (12) Aker Hospital, Oslo, Norway, NO (13) Clinic for Internal Medicine, Jena, Germany, DE (14) Department of Radiology and Nuclear Medicine, Free University, Berlin, Germany, DE (15) Institute of Clinical Medicine, University of Siena, Siena, Italy, IT (16) Medical Centre, Warsaw, Poland, PL (17) Clinical Hospital, Zagreb, Croatia, YU (18) Ruhr University, Bochum, Germany, DE (19) Lund University, MalmoA', Sweden, SE (20) Centre for Metabolic Bone Disease, Sheffield, UK, GB (21) Medical Academy, Erfurt, Germany, DE (22) Hospital de San Joao, Oporto, Portugal, PT (23) The Children Memorial Health Institute, Warsaw, Poland, PL (24) Laboratory for the Research of Musculoskeletal System, University of Athens, Athens, Greece, GR (25) Centre de Medecine SpecialiseA'e, Montceau-les-Mines, France, FR (26) Institute of Rheumatic Diseases, Piestany, Slovakia, CS (27) Institute of Social Medicine, Lubeck, Germany, DE (28) Academy of Medicine, Szczecin, Poland, PL (29) Department of Epidemiology and Department of Internal Medicine, Erasmus University, Rotterdam, The Netherlands, NL (30) National Institute of Rheumatology and Physiotherapy, Budapest, Hungary, HU (31) Faculty of Medicine, University of Madrid, Madrid, Spain, ES (32) Department of Medicine and Therapeutics, University of Aberdeen, Aberdeen, UK, GB (33) Institute for Diagnostic Radiology, Humboldt University, Berlin, Germany, DE (34) Institute of Social Medicine, University of Heidelberg, Heidelberg, Germany, DE (35) Department of Internal Medicine, Charles University, Prague, Czech Republic, CS (36) School of Nursing, Midwifery and Health Visiting, University of Manchester, Manchester, UK, GB (37) Department of Medicine, University Hospital, Graz, Austria, AT (38) Department of Rheumatology, Royal Cornwall Hospital, Truro, UK, GB Article note: Received: 23 October 2001 / Accepted: 31 January 2002

Byline: Herbert W. Hethcote (1), P. van den Driessche (2) Keywords: Key words:aEpidemiologic modeling -- SIS model -- Delay -- Threshold -- Hopf bifurcation Abstract: aThe SISaepidemiologic models have a delay corresponding to the infectious period, and disease-related deaths, so that the population size is variable. The population dynamics structures are either logistic or recruitment with natural deaths. Here the thresholds and equilibria are determined, and stabilities are examined. In a similar SIS model with exponential population dynamics, the delay destabilized the endemic equilibrium and led to periodic solutions. In the model with logistic dynamics, periodic solutions in the infectious fraction can occur as the population approaches extinction for a small set of parameter values. Author Affiliation: (1) Department of Mathematics, University of Iowa, Iowa City, IA 52242, USA, US (2) Department of Mathematics and Statistics, University of Victoria, Victoria, B.C. V8W 3P4, Canada, CA Article note: Received: 10 January 1997 / 18 November 1997

Author(s): Giuseppe Remuzzi 1,2,3, Richard Glassock 4,* More than a dozen years have elapsed since the original criteria for definition and classification of generic (not specific to type of disease [...]