Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EPIDEMIOLOGY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed2000

Epidemiological, clinical and control investigations on field porcine coccidiosis: clinical, epidemiological and parasitological paradigms?

For several reasons, we are convinced that the parasitologist community must look again at porcine neonatal coccidiosis. We find it surprising that this disease is seldom addressed, and that assumptions are not always supported by clinico-epidemiological analysis. For example, the relationship between diarrhoea and the excretion of oocysts during experimental infection versus field infection is not questioned. Lindsay et al. review parasitological knowledge of this disease in the latest (1999) edition of Diseases of swine. Although this paper is divided into two parts, we have three distinct objectives: (1) to bring to the debate our experience in the medical control of this disease; (2) to propose a diagnostic methodology; (3) to raise some questions on various clinical, epidemiological and parasitological unknowns.

Animals↗
PubMed2000

The European Study of Epidemiology and Treatment of Cardiac Inflammatory Diseases (ESETCID). First epidemiological results.

By including immunohistochemical parameters the WHF Task Force for the Definition of Acute and Chronic Myocarditis expanded the light microscopical Dallas criteria of myocarditis. The rapid development of new molecular biological techniques such as polymerase chain reaction (PCR) and in-situ hybridization has improved our understanding of the underlying etiological and pathophysiological mechanisms in inflammatory heart disease. Treatment of dilated cardiomyopathy with inflammation is still controversial, however. The American Myocarditis Treatment Trial could not demonstrate a significant difference in the improvement of ejection fraction between patients with active myocarditis in the cyclosporine/prednisolone treated group when compared to placebo. In the European Study of Epidemiology and Treatment of Inflammatory Heart Disease (ESETCID) patients with acute or chronic myocarditis are treated specifically according to the etiology of the disease. Patients are screened not only for infiltrating cells, but also for the presence of persisting viral genome (enterovirus, cytomegalovirus and adenovirus). By investigating endomyocardial biopsies of 3,055 patients ongoing inflammatory processes in the heart could be found in 17.2%. Only 182 showed a reduced ejection fraction below 45% fulfilling the entrance criteria for the ESETCID trial. These data imply that in symptomatic patients inflammatory heart muscle disease has to be considered regardless of left ventricular function and that endomyocardial biopsy can be an important tool for diagnosis. Virus could be detected in 11.8% (enterovirus 2.2%, cytomegalovirus 5.4%, adenovirus 4.2%). These first epidemiological results of this prospective randomized study demonstrate that viral persistence may contribute to the pathogenesis of inflammatory heart muscle disease, and that in chronic myocarditis viral persistence occurs in a smaller percentage of patients compared to previously published studies which were performed on highly selected patients.

Cardiomyopathies↗
PubMed1998

Measurement of risk for mental disorders and competence in a psychiatric epidemiologic community survey: the National Institute of Mental Health Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study.

This paper describes the implementation of the National Institute of Mental Health Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) study's goals of measuring risk factors and competence. The emphasis is on the development and testing of the measures. Relevant constructs for measurement of risk and competence in relation to psychopathology were selected and pilot tested prior to the field trials. A structured interview was developed and field tested using lay interviewers. Using the full sample from the field trials (n = 1285 caretaker-youth pairs), sample means, standard deviations, internal consistencies, parent-youth agreement, and associations with childhood disorder were computed. Descriptive statistics reveal a range of scores and means consistent with norming samples, when available, Internal consistencies were moderate to high. Parent-youth agreement on factual items was excellent and on scales was consistent with the literature. Several strong associations were found between risk factors and disorder, although most were related to disorder in general and not specific to a diagnostic category. This instrument provides a means of obtaining data that will be useful to researchers conducting epidemiologic and clinical studies designed to contribute to the understanding of mental disorders in children and adolescents, including nosology, risk factors, context, adaptive functioning, and treatment.

Adolescent↗
PubMed1997

Concept of segmentation in nosocomial epidemiology: epidemiological relation among antimicrobial-resistant isolates of Pseudomonas aeruginosa.

Typing studies on 271 clinical strains of Pseudomonas aeruginosa isolated from the University Teaching Hospital were conducted to obtain their serotypes, antimicrobial susceptibility patterns and plasmid profiles. These strain typing data were arranged through multivariate statistical analysis by computation to classify individual strains. Plots in the scatter diagrams obtained from both principal component analysis and quantification theory type III expressed the clinical strains of P. aeruginosa with various degrees of antimicrobial resistance. Epidemiological relation among these clinical strains was analysed in those scatter diagrams by segmentation, in combination with their epidemiological information (date and place of isolation, type of specimen, etc.). The results showed that the serotype E strains both with high-level resistance to gentamicin and with a plasmid of 3.9 x 10(6) dalton, and the strains resistant to more than five antimicrobial agents, were colonized and localized each in certain clinical wards for inpatients. It was suggested that segmentation analysis could be of practical use in the management of nosocomial infection control against P. aeruginosa with antimicrobial resistance.

Cluster Analysis↗
PubMed2000

Epidemiological surveillance of Guillain-Barré syndrome in Sweden, 1996-1997. Network members of the Swedish GBS Epidemiology Study Group.

OBJECTIVES: To set up an epidemiological surveillance system of Guillain-Barré syndrome (GBS) in Sweden and to evaluate the pilot practice of the system for 2 years. MATERIAL AND METHODS: A network of neurologists reported incident patients with a GBS diagnosis among a general population of 4.5 million inhabitants in Sweden during 1996 1997. Historical GBS data from the national hospital in-patient registry were used for predicting incidences and controlling under-reporting. RESULTS: One hundred and seventeen cases were reported. No alarm signals were identified during the study period. A re-analysis of data in 1996 revealed: 1) a higher than expected incidence in the population aged below 40 years in January, and 2) 27% under-reporting mainly associated to one hospital and to GBS patients hospitalized outside neurological departments. Threshold values for GBS incidences among the general and selected populations were obtained from corrected data. CONCLUSION: - The Swedish Network for GBS Surveillance can provide immediate support for epidemiological evaluation of suspected outbreaks or increased GBS incidence.

Adult↗
PubMed2002

Epidemiology of contact allergy: an estimation of morbidity employing the clinical epidemiology and drug-utilization research (CE-DUR) approach.

Clinical epidemiology (CE) is considered unable to estimate morbidity concerning either contact sensitization (CS) or allergic contact dermatitis (ACD) at the population level. Drug-utilization research (DUR) methods estimate the morbidity of suitable diseases based on prescription data for disease-specific drugs. Our objective was to estimate population figures for incidence and prevalence of ACD and CS based on sales data for patch test material in Germany and on patient data from the Information Network of Departments of Dermatology (IVDK). Approximately 600000 standard series are sold per year in Germany, according to the 2 main manufacturers. This raw sales figure was corrected for certain effects (discarded preparations, proportion of formerly patch-tested patients, proportion of patients with ACD seeking medical advice) to obtain an estimate of the denominator of patients eligible for patch testing annually, and combined with patch test results from the Information Network of Departments of Dermatology (IVDK). In 17.8% (of 9266 IVDK patients) ACD was established. Extrapolated to the general population, an incidence of ACD of between 1.7 and 7 per 1000 per year was estimated, depending on whether conservative or more liberal assumptions concerning the above effects were made. Of 78067 IVDK patients tested between 1992 and 2000, 46.8% had at least 1 positive reaction (+ to + + +), and 22.7% had at least 1 stronger positive reaction (+ + or + + +). The 9-year prevalence of CS was estimated to lie between 4.0% and 16.6% for the first outcome, and between 2.0% and 8.1% for the second. Concerning single allergens, 1.9-4.5 million individuals are probably sensitized to nickel, and 1.4-3.4 million to fragrance mix among the German population of 82 million inhabitants. The morbidity data found in this study are in good accordance with data from population-based epidemiological studies. In comparison to these, the CE-DUR approach seems to be an economically feasible method to estimate continuously the population impact of ACD and CS.

Allergens↗
PubMed1997

How to select and interpret molecular strain typing methods for epidemiological studies of bacterial infections: a review for healthcare epidemiologists. Molecular Typing Working Group of the Society for Healthcare Epidemiology of America.

Strain typing is an integral part of epidemiological investigations of nosocomial infections. Methods for distinguishing among bacterial strains have improved dramatically over the last 5 years, due mainly to the introduction of molecular technology. Although not all molecular techniques are equally effective for typing all organisms, pulsed-field gel electrophoresis is the technique currently favored for most nosocomial pathogens. Criteria to aid epidemiologists in interpreting results have been published. Nucleic acid amplification-based typing methods also are applicable to many organisms and can be completed within a single day, but interpretive criteria still are under debate. Strain typing cannot be used to replace a sound epidemiological investigation, but serves as a useful adjunct to such investigations.

Bacterial Typing Techniques↗
PubMed2000

Multicenter evaluation of epidemiological typing of methicillin-resistant Staphylococcus aureus strains by repetitive-element PCR analysis. The European Study Group on Epidemiological Markers of the ESCMID.

Rapid and efficient epidemiologic typing systems would be useful to monitor transmission of methicillin-resistant Staphylococcus aureus (MRSA) at both local and interregional levels. To evaluate the intralaboratory performance and interlaboratory reproducibility of three recently developed repeat-element PCR (rep-PCR) methods for the typing of MRSA, 50 MRSA strains characterized by pulsed-field gel electrophoresis (PFGE) (SmaI) analysis and epidemiological data were blindly typed by inter-IS256, 16S-23S ribosomal DNA (rDNA), and MP3 PCR in 12 laboratories in eight countries using standard reagents and protocols. Performance of typing was defined by reproducibility (R), discriminatory power (D), and agreement with PFGE analysis. Interlaboratory reproducibility of pattern and type classification was assessed visually and using gel analysis software. Each typing method showed a different performance level in each center. In the center performing best with each method, inter-IS256 PCR typing achieved R = 100% and D = 100%; 16S-23S rDNA PCR, R = 100% and D = 82%; and MP3 PCR, R = 80% and D = 83%. Concordance between rep-PCR type and PFGE type ranged by center: 70 to 90% for inter-IS256 PCR, 44 to 57% for 16S-23S rDNA PCR, and 53 to 54% for MP3 PCR analysis. In conclusion, the performance of inter-IS256 PCR typing was similar to that of PFGE analysis in some but not all centers, whereas other rep-PCR protocols showed lower discrimination and intralaboratory reproducibility. None of these assays, however, was sufficiently reproducible for interlaboratory exchange of data.

Bacterial Typing Techniques↗
PubMed1995

Case-control study on the epidemiology of cluster headache. I: Etiological factors and associated conditions. Italian Cooperative Study Group on the Epidemiology of Cluster Headache (ICECH).

The etiological and physiopathological mechanisms of cluster headache (CH) are still largely unknown. The majority of the studies published on the possible risk factors and conditions associated with CH rely on either anecdotal observations or generalizations and have not been supported by serious epidemiological investigations. The aim of this case-control study was to evaluate the real association of life habits and general risk factors with CH. CH was associated only with cigarette smoking, head trauma and a positive family history for headache. Further epidemiologic studies are probably necessary in order to find clues to CH etiology.

Adult↗
PubMed2002

Influence of nonsystemic transmission on the epidemiology of insect borne arboviruses: a case study of vesicular stomatitis epidemiology in the western United States.

Nonsystemic transmission, where a pathogen is transmitted between infected and uninfected vectors without the vertebrate host becoming viremic, may provide an explanation for transmission in systems where the vertebrate hosts have been difficult to identify. This transmission pathway had been previously demonstrated for tick-borne viruses and bacteria, but the recent demonstration for Simulium and vesicular stomatitis virus is the first for a blood-feeding insect. The epidemiology of vesicular stomatitis viruses has been difficult to understand, and nonsystemic transmission may be important. We use mathematical formulations of the basic reproduction number, R(0), to compare systemic and nonsystemic transmission. The absence of a latent period before host infectiousness in nonsystemic transmission may allow a more rapid increase in prevalence in the biting flies early in the development of a new outbreak. Aggregation of flies between hosts and at favored feeding sites on hosts will be important, but further data on nonsystemic transmission as a function of space and time are required to fully assess this pathway. The data needed to compare the two pathways and their relative roles in virus epidemiology are discussed.

Animals↗
PubMed1999

Chronic venous disorders of the leg: epidemiology, outcomes, diagnosis and management. Summary of an evidence-based report of the VEINES task force. Venous Insufficiency Epidemiologic and Economic Studies.

BACKGROUND: To critically review the classification, epidemiology, outcomes, diagnosis and treatment of chronic venous disorders of the leg (CVDL), to issue evidence-based recommendations, and to identify areas requiring further research. METHODS: Articles identified by an extensive literature search were scored by members of an international task force. Only those articles with a moderate or strong rating for internal validity were retained. RESULTS: A scoring system weighing CVDL severity according to the probability of ulcer occurrence is proposed. Epidemiological data on the frequency of CVDL and its risk factors are reviewed. The following items are evaluated: costs associated with treatment; clinical outcomes related to CVDL and its treatment; available generic and disease-specific measures of quality of life; diagnostic procedures used to detect venous reflux; and efficacy of available treatments. CONCLUSIONS: CVDL is an important public health problem, based on its prevalence, cost and impact on quality of life. High-priority areas for research on CVDL are identified.

Chronic Disease↗
PubMed1989

The ovine cysticercosis as models for research into the epidemiology and control of the human and porcine cysticercosis Taenia solium: I. Epidemiological considerations.

A brief review is given of the transmission dynamics of the ovine cysticercoses Taenia hydatigena and T. ovis. The importance of the basic reproductive rate (Ro) and the parasite, host and socio-ecological factors determining the epidemiological steady states of Taeniidae are described. The transmission dynamics of these ovine cysticercoses have been used as models to assist in identifying the biological and epidemiological research needed for developing strategies for the control of porcine cysticercosis caused by T. solium.

Animals↗
PubMed1987

Radiologic appearance of gallstones and its relationship with biliary symptoms and awareness of having gallstones. Observations during epidemiological studies. Rome Group for the Epidemiology and Prevention of Cholelithiasis (GREPCO).

In the course of two cross-sectional epidemiological surveys carried out by the Rome Group for Epidemiology and Prevention of Cholelithiasis (GREPCO), cholecystography was performed in 82 of 126 subjects identified by means of ultrasonography as having gallstones. In four subjects gallstones were not detected by cholecystography. The x-ray characteristics of the gallbladder and gallstones of the remaining 78 subjects were related to age, sex, presence of biliary symptoms in the five years prior to the study, and awareness of having gallstones. Twenty-three of the 78 gallstone subjects (29.5%) showed a nonvisualized gallbladder. Among the 55 subjects with visualized gallbladder, 16 (29.1%) and 28 (50.9%) showed radiopaque and solitary stones, respectively. The mean diameter of the largest stone was 19.7 mm +/- 11.2 (SD). Age was related inversely to the number of stones. X-ray characteristics of gallstones did not differ between men and women. Presence of biliary symptoms in the five years prior to the study or awareness of having gallstones were not related to any radiologic feature, either in univariate or multivariate statistical analysis which included age, sex, weight, and height as possible confounding variables. Nineteen (24.3%) of the 78 subjects showed gallstones which would have been suitable for medical therapy with bile acids (ie, radiolucent, with a diameter of less than 20 mm, and in a visualized gallbladder).

Adult↗
PubMedDate not supplied

[The epidemiological patterns of rubella and the ways to improve epidemiological surveillance].

The retrospective epidemiological analysis of rubella morbidity in Perm has revealed that the epidemic process of rubella is revived every 2-3 years in winter and spring. Children of preschool age in organized groups are mainly affected; 42.5% of these children have no specific antibodies. Among adults, the risk group consists mainly of women aged 20-29 years. The intensity of the epidemic process of rubella in organized groups of children has been found to depend on the general level of collective immunity. The hemagglutination inhibition test with the use of rubella antigenic diagnosticum may be recommended for practical use in the system of epidemiological surveillance for the differential diagnosis of rubella with a view to distinguish it from other infections, the determination of the scope of the virus circulation among different groups of the population and the timely diagnosis of rubella in pregnant women.

Child, Preschool↗
PubMed1997

Molecular epidemiology of insulin-dependent diabetes mellitus: WHO DiaMond Project. WHO DiaMond Molecular Epidemiology Sub-Project Group.

The WHO DiaMond Molecular IDDM Epidemiology Sub-Project is testing the hypothesis that population variation in the frequency of high-risk HLA-DQ alleles is a primary determinant of the global patterns of IDDM incidence. Data are currently available for 16 populations, and reveal significant variations in the frequencies of HLA-DQA1 and DQB1 alleles among the case and the control groups. However, DQA1 x Arg-(52) and DQB1 x non-Asp-57 (ND) were consistent and independent markers of IDDM susceptibility in all populations, except Japan. Individuals who carried only DQA1 x R and DQB1 x ND alleles had an IDDM risk similar to that observed for first degree relatives of affected individuals (3%-5%). Such information is essential for the development of clinical strategies or disease prevention approaches for the general population or individuals at high-risk. Thus, the DiaMond Molecular Epidemiology Sub-Project provides an excellent model that can be followed to assess the impact of new genetic discoveries on medicine and public health practice for diabetes and other chronic diseases.

Adolescent↗
PubMed1998

The molecular epidemiology of tuberculosis in Zaragoza, Spain: a retrospective epidemiological study in 1993.

SETTING: The incidence of tuberculosis (TB) in Spain is one of the highest in Europe. In Zaragoza region the incidence rate of tuberculosis and the acquired immune deficiency syndrome (AIDS) are close to the national average. OBJECTIVE: To better define the molecular epidemiology of tuberculosis in an area of Europe where this has not been previously studied. DESIGN: A retrospective epidemiological study on tuberculosis was conducted in Zaragoza, a region of Spain, in 1993. The study population consisted of 226 patients from whom positive culture and complete clinical and demographic data were available. Mycobacterium tuberculosis strains were typed by standard restriction fragment length polymorphism (RFLP). A cluster was defined as two or more isolates with identical RFLP patterns when five or more copies of IS6110 are present. The 137 non-clustered patients were compared with the 89 clustered patients and studied by using univariate analysis. RESULTS: Thirty-nine percent of the patients were clustered, suggesting possible recent transmission. Infection with drug-resistant M. tuberculosis was associated with a decreased risk of being in a cluster. The strains isolated from human immunodeficiency virus (HIV)-positive patients were not associated with clustering. We found that immigration was not a major determinant in the total number of TB cases. CONCLUSION: Immigration, HIV and drug resistance were not associated with recent transmission. More than 50% of the clusters contained two or three patients, indicating that small outbreaks were responsible for most of the tuberculosis cases. Our RFLP typing results indicate that a TB control programme should be implemented in Spain in order to lower transmission of TB.

AIDS-Related Opportunistic Infections↗
PubMed1998

[European Program for Intervention Epidemiology Training (EPIET): a training epidemiologic intervention in Europe].

The European programme for interventional epidemiology training (EPIET) offers a two year practical training in European national institutes mandated for the surveillance and control of communicable diseases. The training, closely supervised by senior epidemiologists, allows each EPIET fellow to learn while serving and conducting tasks devoted to intervention epidemiologists (surveillance, investigation, research, aid to decision making, and communication with the public, the media, the health authorities and the scientific community). The programme is equally funded by the European Commission, the 15 member states, Norway and the World Health Organisation. This training, derived from the North American and British experiences offers a practical complement to knowledge acquired from European universities. EPIET fellows, their supervisors and colleagues from training institutes have rapidly formed a network of intervention epidemiologists necessary for conducting and coordinating the surveillance of communicable diseases in Europe.

Communicable Diseases↗