Home About us Contact | |||
Epidemic
Kinds of Epidemic Terms modified by Epidemic Selected AbstractsHAVE EFFORTS TO REDUCE SMOKING REALLY CONTRIBUTED TO THE OBESITY EPIDEMIC?ECONOMIC INQUIRY, Issue 2 2009JAMES NONNEMAKER Two of the most notable trends in public health over the past 30 yr are the reductions in smoking rates and the rapid rise in obesity rates. Several studies have investigated the relationship between these trends but have drawn different conclusions. In this article, we revisit this issue, attempting to clarify the prior discrepant results. Overall, we find no support for the claim that rising cigarette taxes have significantly contributed to rising obesity rates. Instead, we find only a moderately sized effect among former smokers. (JEL I12) [source] ETHICAL PROBLEMS IN CONDUCTING RESEARCH IN ACUTE EPIDEMICS: THE PFIZER MENINGITIS STUDY IN NIGERIA AS AN ILLUSTRATIONDEVELOPING WORLD BIOETHICS, Issue 1 2010EMMANUEL R. EZEOME ABSTRACT The ethics of conducting research in epidemic situations have yet to account fully for differences in the proportion and acuteness of epidemics, among other factors. While epidemics most often arise from infectious diseases, not all infectious diseases are of epidemic proportions, and not all epidemics occur acutely. These and other variations constrain the generalization of ethical decision-making and impose ethical demands on the individual researcher in a way not previously highlighted. This paper discusses a number of such constraints and impositions. It applies the ethical principles enunciated by Emmanuel et al.1 to the controversial Pfizer study in Nigeria in order to highlight the particular ethical concerns of acute epidemic research, and suggest ways of meeting such challenges. The paper recommends that research during epidemics should be partly evaluated on its own merits in order to determine its ethical appropriateness to the specific situation. Snap decisions to conduct research during acute epidemics should be resisted. Community engagement, public notification and good information management are needed to promote the ethics of conducting research during acute epidemics. Individual consent is most at risk of being compromised, and every effort should be made to ensure that it is maintained and valid. Use of data safety management boards should be routine. Acute epidemics also present opportunities to enhance the social value of research and maximize its benefits to communities. Ethical research is possible in acute epidemics, if the potential challenges are thought of ahead of time and appropriate precautions taken. [source] An Epidemic of Illicit Fentanyl Deaths in Cook County, Illinois: September 2005 through April 2007JOURNAL OF FORENSIC SCIENCES, Issue 2 2008J. Scott Denton M.D. Abstract:, Between September 2005 and April 2007, 350 fentanyl intoxication deaths were investigated and certified by the Cook County Medical Examiners Office. Investigations revealed that the majority of these fatalities were by intravenous injection of a white powder followed by a rapid collapse. The fentanyl was clandestinely produced in a lab in Toluca, Mexico and sold by the Mickey Cobra street gang. The term "Drop Dead" was coined for this "tainted heroin." Postmortem samples were screened by ELISA and confirmed by standard GC-MS methods. Fentanyl fatalities peaked at 47 per month in May and June 2006. Fifty-two percent were single fentanyl intoxications, with the remainder accompanied by either cocaine, morphine from heroin, or alcohol. This epidemic stressed the limited resources of the toxicology laboratory and autopsy service of the Medical Examiners Office. The clandestine lab was terminated, distributing gang members and leaders arrested, and the epidemic ceased in April 2007. [source] Epidemic of Cesarean Section at the General, Private and University Hospitals in ThailandJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2000Dr. Boonsri Chanrachakul Abstract Objective: To undertake a survey of cesarean section in the general, private and university hospitals in Thailand. Methods: Postal questionnaires were sent to all the general, private and university hospitals with 200 beds or more. The questionnaires were prepared to find out the percentage, the indications and the trend of cesarean delivery, the measures taken to decrease cesarean section rate, and the practice of external cephalic version (ECV) and vaginal birth after cesarean section (VBAC) in the hospitals. Results: The overall response rate was 88%. Mean cesarean section rates were 24, 48, and 22% in the general, private and university hospitals, respectively. Cesarean section rates in most of the hospitals were increased in the past 5 years namely 78% in the general hospitals, 50% in the private hospitals, 66% in the university hospitals. However, only 38% of the hospitals had measures to regulate this operation. Repeated cesarean section was the most common indication in the private (63%) and the university hospitals (88%) while failure to progress was the most common indication in the general hospitals (55%). ECV and VBAC were performed in 26 and 12% of the hospitals. They were, however, not the standard practices. Conclusion: Rising of cesarean section rate without any measure to regulate it is the problem in the developing countries. Standardised labor management and reduction of unnecessary primary cesarean section will automatically reduce repeated operation and overall cesarean section. [source] IPMN,Controversies in an "Epidemic"JOURNAL OF SURGICAL ONCOLOGY, Issue 2 2006C. Max Schmidt MD No abstract is available for this article. [source] Fetal Alcohol Spectrum,The Hidden Epidemic in Our CourtsJUVENILE AND FAMILY COURT JOURNAL, Issue 4 2001KATHRYN PAGE PH.D. ABSTRACT This article discusses the basics of Fetal Alcohol Syndrome and Fetal Alcohol Effects (FAS/E): the history, nature, prevalence, causes, and effects of prenatal exposure to alcohol. Some of the unique features of FAS/E are explored, particularly those that make it so hard to spot and those that predispose people to nonproductive or criminal activity. The presentation of FAS/E in Juvenile Court is discussed and put in the context of the multiplicity of factors pertaining to delinquency; finally, innovative interventions, approaches and resources are laid out. Issues surrounding FAS/E as they appear in Family Court are then explored, with emphasis on the intergenerational transmission of this array of conditions and how we might interrupt such transmission. [source] The United Nations on the Demographic Impact of the AIDS EpidemicPOPULATION AND DEVELOPMENT REVIEW, Issue 3 2000Article first published online: 27 JAN 200 A report prepared by the Joint United Nations Programme on HIV/AIDS (UNAIDS) and released in Geneva on 27 June 2000 (just prior to the XIIIth International AIDS Conference held in Durban, South Africa) updates estimates of the demographic impact of the epidemic. It characterizes AIDS in the new millennium as presenting "a grim picture with glimmers of hope",the latter based on the expectation that national responses aimed at preventing and fighting the disease are in some places becoming more effective. According to the report, which emphasizes the considerable statistical weaknesses of its global estimates, the number of people living with HIV/AIDS in 1999 was 34.3 million (of which 33.0 million were adults and 1.3 million were children under age 15; slightly less than half of the adults affected, 15.7 million, were women). Deaths attributed to AIDS in 1999 amounted to 2.8 million, bringing the total since the beginning of the epidemic to 18.8 million. These figures represent moderate upward revisions of earlier UN estimates shown in the Documents section of PDR 25, no. 4. The revised estimate of the number of persons newly infected with HIV in 1999 is, in contrast, slightly lower: 5.4 million, of which 4.7 million were adults and 2.3 million were women. An excerpt from the 135-page Report on the Global HIV/AIDS Epidemic, focusing on countries in the worst-affected area, sub-Saharan Africa, is reproduced below. (Figures shown have been renumbered.) [source] Epidemic of plurality and contributions of assisted reproductive technology therein,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 2 2009Monica Kapoor Abstract A commentary on contributions of ART to the pandemic of multiple gestations is presented and mechanistic aspects therein are explored. © 2009 Wiley-Liss, Inc. [source] REVIEW ARTICLE: Chlamydia trachomatis, a Hidden Epidemic: Effects on Female Reproduction and Options for TreatmentAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2010Alison J. Carey Citation Carey AJ, Beagley KW. Chlamydia trachomatis, a hidden epidemic: effects on the female reproduction and options for treatment. Am J Reprod Immunol 2010 The number of genital tract Chlamydia trachomatis infections is steadily increasing worldwide, with approximately 50,70% of infections asymptomatic. There is currently no uniform screening practice, current antibiotic treatment has failed to prevent the increased incidence, and there is no vaccine available. We examined studies on the epidemiology of C. trachomatis infections, the effects infections have on the female reproductive tract and subsequent reproductive health and what measures are being taken to reduce these problems. Undetected or multiple infections in women can lead to the development of severe reproductive sequelae, including pelvic inflammatory disease and tubal infertility. There are two possible paradigms of chlamydial pathogenesis, the cellular and immunological paradigms. While many vaccine candidates are being extensively tested in animal models, they are still years from clinical trials. With no vaccine available and antibiotic treatment unable to halt the increased incidence, infection rates will continue to increase and cause a significant burden on health care systems. [source] SARS, Xenotransplantation and Bioterrorism: Preventing the Next EpidemicAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2003Jay A. Fishman First page of article [source] A Test for Constant Fatality Rate of an Emerging Epidemic: With Applications to Severe Acute Respiratory Syndrome in Hong Kong and BeijingBIOMETRICS, Issue 3 2008K. F. Lam Summary The etiology, pathogenesis, and prognosis for a newly emerging disease are generally unknown to clinicians. Effective interventions and treatments at the earliest possible times are warranted to suppress the fatality of the disease to a minimum, and inappropriate treatments should be abolished. In this situation, the ability to extract most information out of the data available is critical so that important decisions can be made. Ineffectiveness of the treatment can be reflected by a constant fatality over time while effective treatment normally leads to a decreasing fatality rate. A statistical test for constant fatality over time is proposed in this article. The proposed statistic is shown to converge to a Brownian motion asymptotically under the null hypothesis. With the special features of the Brownian motion, we are able to analyze the first passage time distribution based on a sequential tests approach. This allows the null hypothesis of constant fatality rate to be rejected at the earliest possible time when adequate statistical evidence accumulates. Simulation studies show that the performance of the proposed test is good and it is extremely sensitive in picking up decreasing fatality rate. The proposed test is applied to the severe acute respiratory syndrome data in Hong Kong and Beijing. [source] When half of the population died: the epidemic of hemorrhagic fevers of 1576 in MexicoFEMS MICROBIOLOGY LETTERS, Issue 1 2004Rodofo Acuna-Soto Abstract During the 16th century, Mexico suffered a demographic catastrophe with few parallels in world's history. In 1519, the year of the arrival of the Spaniards, the population in Mexico was estimated to be between 15 and 30 million inhabitants. Eighty-one years later, in 1600, only two million remained. Epidemics (smallpox, measles, mumps), together with war, and famine have been considered to be the main causes of this enormous population loss. However, re-evaluation of historical data suggests that approximately 60,70% of the death toll was caused by a series of epidemics of hemorrhagic fevers of unknown origin. In order to estimate the impact of the 1576 epidemic of hemorrhagic fevers on the population we analyzed the historical record and data from the 1570 and 1580 censuses of 157 districts. The results identified several remarkable aspects of this epidemic: First, overall, the population loss for these 157 districts was 51.36%. Second, there was a clear ethnic preference of the disease, the Spanish population was minimally affected whereas native population had high mortality rate. Third, the outbreak originated in the valleys of central Mexico whence it evolved as an expansive wave. Fourth, a positive correlation between altitude and mortality in central Mexico was found. Fifth, a specific climatic sequence of events was associated with the initiation and dissemination of the hemorrhagic fevers. Although the last epidemic of hemorrhagic fevers in Mexico ended in 1815, many questions remain to be answered. Perhaps the most relevant ones are whether there is a possible reemergence of the hemorrhagic fevers and how vulnerable we are to the disease. [source] Chytrid infections of Daphnia pulicaria: development, ecology, pathology and phylogeny of Polycaryum laeveFRESHWATER BIOLOGY, Issue 4 2006PIETER T. J. JOHNSON Summary 1. We combined ecological surveys, life table studies, microscopy and molecular sequencing to determine the development, ecology, pathology and phylogeny of Polycaryum laeve, an endoparasite of cladocerans. We report the first records of P. laeve from North America, where we have used a polymerase chain reaction primer and microscopic examination to confirm infections in 14 lakes. Infections are highly pathogenic and caused increased mortality, reduced growth, and reproductive castration in Daphnia pulicaria during life table studies. 2. Biweekly data from Allequash Lake (Wisconsin, U.S.A.) throughout 2003 indicated that fecundity and infection prevalence were inversely correlated. Infection prevalence was highest in late winter and early spring (up to 80%) and lowest during late summer. Epidemics were generally followed by sharp declines in host population density (up to 99%). 3. Within the haemocoel of its host, P. laeve forms thick-walled sporangia, which occur systemically in later stages of infection. Fungal thalli associate closely with muscle fibres and connective tissue, leading to degeneration as the infection becomes advanced. Following death of the host, flagellated zoospores are released through an exit papilla on the sporangium. Based on the infection-induced castration of the host and increases in infection prevalence with Daphnia size, we postulate that transmission is horizontal, but may be indirect through an additional host or free-living stage. 4. Molecular and morphological data clearly indicate that P. laeve belongs in the fungal phylum Chytriodiomycota, order Blastocladiales. Based on ribosomal RNA gene sequences and morphological features, we transfer the genus Polycaryum from the Haplosporidia to the Chytridiomycota, and designate a lectotype and epitype for P. laeve. Considering the high prevalence of P. laeve infection within Daphnia populations, the frequency with which we detected infections among lakes, and the keystone importance of large-bodied Daphnia in aquatic food webs, we suggest that P. laeve may exert a regulatory influence on Daphnia populations in lake ecosystems. [source] Effect 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] From Malthus to Modern Growth: Can Epidemics Explain the Three Regimes?*INTERNATIONAL ECONOMIC REVIEW, Issue 2 2003Nils-Petter Lagerlöf We model demographic and economic long-run development in a setting where mortality is endogenous and subject to epidemic shocks. The model replicates the full transition from Malthusian stagnation to modern growth. Consistent with the historical facts, the economy also passes an intermediate post-Malthusian phase where growth rates of both population and per capita income increase simultaneously, as mortality rates fall and become less volatile. The escape from the Malthusian trap is the result of a series of mild epidemic shocks, making it inevitable at some stage, but its timing random. Calibrations show that it can differ by thousands of generations, absent differences in exogenous parameters. [source] HIV Epidemics in Africa: What Explains the Variations in HIV Prevalence?IUBMB LIFE, Issue 4-5 2002Anne Buvé Abstract There are large differences in the prevalence of HIV infection between different regions in sub-Saharan Africa, ranging from less than 10% in pregnant women in most of West Africa, to over 25% in pregnant women in large cities in Eastern and Southern Africa. These differences in HIV prevalence are in many instances due to differences in rate of spread of the virus. The multicenter study on factors determining the differential spread of HIV in four African cities tried to identify factors that could explain differences in spread of HIV between different regions in sub-Saharan Africa. The study was conducted in four cities, including two cities with a relatively low HIV prevalence (Cotonou in Bénin and Yaoundé in Cameroon) and two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia). The difference in HIV prevalence between the four cities could not be explained by differences in sexual behavior. Any differences in sexual behavior were outweighed by differences in factors that influence HIV transmission, i.e. male circumcision and HSV-2 infection. These findings have important implications for the design of interventions. [source] Adaptation of the Forecasting Model DOWNCAST for Determination of Downy Mildew Epidemics of Oilseed Poppy in Tasmania, AustraliaJOURNAL OF PHYTOPATHOLOGY, Issue 4 2008J. B. Scott Abstract Peronospora cristata, causing downy mildew, has become an economically important pathogen of oilseed poppy (Papaver somniferum) since its first record in Tasmania in 1996. DOWNCAST, originally developed for downy mildew of onion, was evaluated for its ability to predict sporulation and infection of poppy by P. cristata. To assess the influence of the parameters within DOWNCAST, two modifications (POPCAST1 and POPCAST2) of the standard DOWNCAST model were also developed and tested. Initial accuracy of determination of sporulation events by DOWNCAST was 75%, while POPCAST1 (but not POPCAST2) was a significantly more accurate predictor of sporulation events (86%) than DOWNCAST (,2 = 5.74, P = 0.025). This increase in accuracy was attributed to increasing both the rainfall threshold inhibitory to sporulation from 0.2 to 3.0 mm, and the relative humidity threshold for induction and development of sporulation from 95% to 96%. While DOWNCAST, POPCAST1 and POPCAST2 had accuracies of infection determination of 65%, 80% and 75%, respectively, chi-squared analysis indicated no significant difference between models. Preliminary field evaluation indicated that POPCAST1 and POPCAST2 were more sensitive in detecting early infection events than DOWNCAST. Field observations indicated that conditions are frequently conducive for downy mildew spread, therefore the ability to predict early season infection events would allow growers to reduce initial infection rates, and thus inoculum loads later in the season. POPCAST1 and POPCAST2 represent a significant step towards the development of a predictive model for downy mildew in poppy crops. [source] Population genetic structure of Plasmopara viticola in the Western Cape Province of South AfricaMOLECULAR PLANT PATHOLOGY, Issue 6 2007TREVOR KOOPMAN SUMMARY Plasmopara viticola populations in South Africa were studied for two consecutive grape growing seasons, in an organically managed and a conventional fungicide-sprayed vineyard. Three to four samplings in each season were genotyped with four microsatellite markers (GOB, CES, ISA and BER). Population differentiation (Fst) between the conventional fungicide-sprayed vineyard and organically managed vineyard was low (0.004 and 0.016) in both growing seasons, suggesting one metapopulation. However, differences in the relative contribution of the predominant and new genotypes to epidemics in the two vineyards suggested that fungicide applications may have selected for reduced pathogen diversity. In both years and vineyards, sexual (oosporic) reproduction and/or migration occurred throughout the year and contributed between 12 and 74% to the epidemic. Hardy,Weinberg analyses suggest that South African P. viticola populations are randomly mating. Epidemics in both years and vineyards were dominated by one or two genotypes that each contributed between 14 and 67% to the epidemic through asexual reproduction. The remaining genotypes showed low levels of asexual reproduction, with most genotypes never being able to reproduce asexually. However, for some genotypes asexual reproduction was important, as it enabled survival of the genotypes from one season to the next. In total, ten genotypes were able to survive asexually or vegetatively from one season to the next. The populations were further characterized by the presence of a high frequency of isolates that most likely have elevated ploidy levels. [source] Epidemics of type 1 diabetes in ChinaPEDIATRIC DIABETES, Issue 3 2005Ze Yang Objective:, The aim of this study was to search for the seasonal and geographic variations in epidemics of type 1 diabetes in China. Research design and methods:, Incidence data from 22 type 1 diabetes registration centers across China were analyzed. A Poisson regression model with a sine wave function was applied to evaluate the seasonal trends. A scan statistic was used to examine the occurrence of an epidemic. Results:, There was a significant cyclic trend of incidence of type 1 diabetes in China. The northern area had a higher incidence rate than the southern area. Epidemics were discovered in Dalian and Shenyang from late 1992 to late 1993. Conclusions:, There was a strong association of climate and incidence of type 1 diabetes in China, whereby the incidence was higher in the colder areas and in the winter months. Evidence of epidemics existed in two centers in 1992,1993. It is critical to identify the epidemics early and determine the causes of epidemics. [source] On the Political Economy of Plant Disease Epidemics: Capita Selecta in Historical EpidemiologyPLANT PATHOLOGY, Issue 5 2009Eric Boa No abstract is available for this article. [source] Relationship between incidence and severity of cashew gummosis in semiarid north-eastern BrazilPLANT PATHOLOGY, Issue 3 2004J. E. Cardoso The incidence,severity relationship for cashew gummosis, caused by Lasiodiplodia theobromae, was studied to determine the feasibility of using disease incidence to estimate indirectly disease severity in order to establish the potential damage caused by this disease in semiarid north-eastern Brazil. Epidemics were monitored in two cashew orchards, from 1995 to 1998 in an experimental field composed of 28 dwarf clones, and from 2000 to 2002 in a commercial orchard of a single clone. The two sites were located 10 km from each other. Logarithmic transformation achieved the best linear adjustment of incidence and severity data as determined by coefficients of determination for place, age and pooled data. A very high correlation between incidence and severity was found in both fields, with different disease pressures, different cashew genotypes, different ages and at several epidemic stages. Thus, the easily assessed gummosis incidence could be used to estimate gummosis severity levels. [source] Epidemiology and management of Leptosphaeria maculans (phoma stem canker) on oilseed rape in Australia, Canada and EuropePLANT PATHOLOGY, Issue 1 2001J. S. West Phoma stem canker (blackleg), caused by Leptosphaeria maculans, is an important disease on oilseed rape (canola, rapeseed, Brassica napus, Brassica juncea, Brassica rapa) causing seedling death, lodging or early senescence in Australia, Canada and Europe, but not in China. The two forms of L. maculans (A group and B group) that occur on oilseed rape are now considered to be separate species. The epidemiology and severity of phoma stem canker differs between continents due to differences in the pathogen population structure, oilseed rape species and cultivars grown, climate and agricultural practices. Epidemics are most severe in Australia, where only the A group occurs, and can be damaging in Canada and western Europe, where both A and B groups occur, although their proportions vary within regions and throughout the year. Epidemics are slight in China, where the A group has not been found. Dry climates (Australia, western Canada) lengthen the persistence of infected debris and may synchronize the release of airborne ascospores (after rain) with seedling emergence. L. maculans spreads from cotyledon and leaf infections down petioles to reach the stem, with infections on cotyledons and leaves early in the season producing the most damaging stem cankers at the stem base (crown). Development of both crown cankers and phoma stem lesions higher up stems is most rapid in regions with high temperatures from flowering to harvest, such as Australia and Canada. Breeding for resistance (genetic, disease escape or tolerance), stubble management, crop rotation and fungicide seed treatments are important strategies for control of phoma stem canker in all areas. Fungicide spray treatments are justified only in regions such as western Europe where high yields are obtained, and accurate forecasts of epidemic severity are needed to optimize their use. [source] Contagious Divides: Epidemics and Race in San Francisco's ChinatownTHE JOURNAL OF AMERICAN CULTURE, Issue 1 2004Eric A. Anderson No abstract is available for this article. [source] Epidemics of Tomato torrado virus, Pepino mosaic virus and Tomato chlorosis virus in tomato crops: do mixed infections contribute to torrado disease epidemiology?ANNALS OF APPLIED BIOLOGY, Issue 3 2010P. Gómez Torrado disease was first observed in protected tomato crops in the Murcia province of Spain in spring 2001, causing serious concern to regional tomato producers. The disease-causing agent was initially identified as a picorna-like bipartite plant RNA virus, now known as Tomato torrado virus (ToTV), but several additional torradoviruses inducing similar disease symptoms have been described more recently. We studied the incidence of torradoviruses between 2005 and 2008 in two parts of Murcia (Spain) where tomato crops are grown commercially. We also analysed the potential association among ToTV, Pepino mosaic virus (PepMV) and Tomato chlorosis virus (ToCV) in samples showing torrado symptoms of varying severity. ToTV was the only torradovirus found in the samples (predominantly as single infections), but double and triple infections comprising ToTV, PepMV and/or ToCV were also detected. There was no evidence of a specific association among the viruses as the frequencies of mixed infections did not deviate from those expected to occur by chance. Statistical analysis of the potential association between torrado symptoms and the type of infection (single or multiple) was inconclusive. To determine whether co-infections with ToTV and PepMV have any marked influence on the torrado disease, we analysed torrado symptom severity and virus accumulation in tomato plants experimentally infected with ToTV-CE, PepMV-Sp13 and PepMV-PS5 in single and mixed infections. The severity of the torrado symptoms was not affected by the presence of PepMV. In single infections, the ToTV titre remained very low, reaching its maximum in the early stages of infection and declining rapidly thereafter, whereas the disease symptoms became more severe over the same timescale. In mixed infections, the accumulation of both ToTV and PepMV was altered with respect to single infections, and the magnitude of this alteration appeared to be virus and strain specific. Therefore, ToTV and PepMV mixed infections may modulate the epidemiology of both viruses in a complex way by altering virus fitness. The impact of our studies on efforts to track and prevent the spread of torrado disease is discussed. [source] NTE: One target protein for different toxic syndromes with distinct mechanisms?BIOESSAYS, Issue 8 2003Paul Glynn Epidemics of organophosphate-induced delayed neuropathy (OPIDN) have paralysed thousands of people. This syndrome of nerve axon degeneration is initiated by organophosphates which react with neuropathy target esterase (NTE). Dosing experiments with adult chickens raise the possibility that OPIDN is initiated by a gain-of-function mechanism. By contrast, loss of NTE function by mutation causes massive apoptosis in Drosophila brain. Now, Winrow et al. show that nte,/, mice die by mid-gestation, but nte+/, mice appear hyperactive and are more sensitive than wild-type mice to a fatal form of OP toxicity.1 Thus, different toxic syndromes may be initiated via a single target protein. BioEssays 25:742,745, 2003. © 2003 Wiley Periodicals, Inc. [source] Household Epidemics: Modelling Effects of Early Stage VaccinationBIOMETRICAL JOURNAL, Issue 3 2009Nyimvua Shaban Abstract A Markovian susceptible , infectious , removed (SIR) epidemic model is considered in a community partitioned into households. A vaccination strategy, which is implemented during the early stages of the disease following the detection of infected individuals is proposed. In this strategy, the detection occurs while an individual is infectious and other susceptible household members are vaccinated without further delay. Expressions are derived for the influence on the reproduction numbers of this vaccination strategy for equal and unequal household sizes. We fit previously estimated parameters from influenza and use household distributions for Sweden and Tanzania census data. The results show that the reproduction number is much higher in Tanzania (6 compared with 2) due to larger households, and that infected individuals have to be detected (and household members vaccinated) after on average 5 days in Sweden and after 3.3 days in Tanzania, a much smaller difference. [source] The Conservation Relevance of Epidemiological Research into Carnivore Viral Diseases in the SerengetiCONSERVATION BIOLOGY, Issue 3 2007SARAH CLEAVELAND conservación de carnívoros; investigación epidemiológica; moquillo; rabia; Serengeti Abstract:,Recent outbreaks of rabies and canine distemper in wildlife populations of the Serengeti show that infectious disease constitutes a significant cause of mortality that can result in regional extirpation of endangered species even within large, well-protected areas. Nevertheless, effective management of an infectious disease depends critically on understanding the epidemiological dynamics of the causative pathogen. Pathogens with short infection cycles cannot persist in small populations in the absence of a more permanent reservoir of infection. Development of appropriate interventions requires detailed data on transmission pathways between reservoirs and wildlife populations of conservation concern. Relevant data can be derived from long-term population monitoring, epidemic and case-surveillance patterns, genetic analyses of rapidly evolving pathogens, serological surveys, and intervention studies. We examined studies of carnivore diseases in the Serengeti. Epidemiological research contributes to wildlife conservation policy in terms of management of endangered populations and the integration of wildlife conservation with public health interventions. Long-term, integrative, cross-species research is essential for formulation of effective policy for disease control and optimization of ecosystem health. Resumen:,Brotes recientes de rabia y moquillo en poblaciones silvestres del Serengeti muestran que las enfermedades infecciosas constituyen una causa significativa de mortandad que puede resultar en la extirpación regional de especies en peligro, aun en áreas extensas bien protegidas. Sin embargo, el manejo efectivo de una enfermedad infecciosa depende críticamente del entendimiento de la dinámica epidemiológica del patógeno. Los patógenos con ciclo infeccioso corto no pueden persistir en poblaciones pequeñas en ausencia de un reservorio de la infección más permanente. El desarrollo de intervenciones adecuadas requiere de datos detallados de las vías de transmisión entre reservorios y poblaciones de vida silvestre de preocupación para la conservación. Se pueden derivar datos importantes del monitoreo de poblaciones a largo plazo, de patrones de epidemias y de estudios de caso, del análisis genético de patógenos que evolucionan rápidamente, de muestreos sexológicos y de estudios de intervención. Examinamos estudios de enfermedades de carnívoros en el Serengeti. La investigación epidemiológica contribuye a las políticas de conservación de vida silvestre en términos de la gestión de poblaciones en peligro y de la integración de la conservación con intervenciones de salud pública. La investigación a largo plazo e integradora es esencial para la formulación de políticas efectivas para el control de enfermedades y la optimización de la salud del ecosistema. [source] An epidemic of allergic contact dermatitis due to epilating productsCONTACT DERMATITIS, Issue 2 2002A. Goossens Over a period of 19 months, 33 cases of acute allergic contact dermatitis from Veet® epilating waxes and/or the accompanying tissue (Reckitt Benckiser, Massy, France) were observed in France and Belgium. The lesions started on the legs and spread to other parts of the body, especially the face, and were sometimes so severe that hospitalization and/or systemic corticosteroids were required. Primary sensitization occurred as early as after the first application in several patients. Patch tests were performed in 26 of the patients and produced strong positive reactions to the tissue (25 times) and/or the wax (13 times). The allergenic culprits in the wax were modified-colophonium derivatives (colophonium in the standard series testing negatively in all except 4 patients), while methoxy PEG-22/dodecyl glycol copolymer and to a lesser degree lauryl alcohol turned out to be the main causal allergens in the tissue. [source] Explaining the imprisonment epidemicCRIMINOLOGY AND PUBLIC POLICY, Issue 1 2009Philip J. Cook Senior Editor No abstract is available for this article. [source] Fluid Labor and Blood Money: The Economy of HIV/AIDS in Rural Central ChinaCULTURAL ANTHROPOLOGY, Issue 4 2006SHAO Jing This ethnographically grounded "epidemiology" implicates China's liberalized economy in the HIV epidemic among commercial plasma donors in rural central China. It uncovers the pathological confluence of spheres of economic circulations that have created the conditions for value to be extracted not through labor but from human plasma harvested from agricultural producers. This critique has emerged out of, and in turn informed, efforts to forestall the secondary epidemic of AIDS among donors already infected by HIV. The specific history of the production and consumption of blood products in China shows how biotechnology broadly defined can be powerfully refracted by local configurations of economy, technology, and social relations. The ideologically sustained second-order "reality" of benevolent economic imperatives needs to be brought into the critical focus of cultural anthropology. [source] |