Acute Chagas disease in El Salvador 2000-2012 - Need for surveillance and control

Several parasitological studies carried out in El Salvador between 2000-2012 showed a higher frequency of acute cases of Chagas disease than that in other Central American countries. There is an urgent need for improved Chagas disease surveillance and vector control programs in the provinces where acute Chagas disease occurs and throughout El Salvador as a whole.

Intrauterine exposure to carbamazepine and specific congenital malformations: systematic review and case-control study.

OBJECTIVE: To identify specific major congenital malformations associated with use of carbamazepine in the first trimester of pregnancy. DESIGN: A review of all published cohort studies to identify key indications and a population based case-control study to test these indications. SETTING: Review of PubMed, Web of Science, and Embase for papers about carbamazepine exposure in the first trimester of pregnancy and specific malformations, and the EUROCAT Antiepileptic Study Database, including data from 19 European population based congenital anomaly registries, 1995-2005. PARTICIPANTS: The literature review covered eight cohort studies of 2680 pregnancies with carbamazepine monotherapy exposure, and the EUROCAT dataset included 98 075 registrations of malformations covering over 3.8 million births. MAIN OUTCOME MEASURES: Overall prevalence for a major congenital malformation after exposure to carbamazepine monotherapy in the first trimester. Odds ratios for malformations with exposure to carbamazepine among cases (five types of malformation identified in the literature review) compared with two groups of controls: other non-chromosomal registrations of malformations and chromosomal syndromes. RESULTS: The literature review yielded an overall prevalence for a major congenital malformation of 3.3% (95% confidence interval 2.7 to 4.2) after exposure to carbamazepine monotherapy in the first trimester. In 131 registrations of malformations, the fetus had been exposed to carbamazepine monotherapy. Spina bifida was the only specific major congenital malformation significantly associated with exposure to carbamazepine monotherapy (odds ratio 2.6 (95% confidence interval 1.2 to 5.3) compared with no antiepileptic drug), but the risk was smaller for carbamazepine than for valproic acid (0.2, 0.1 to 0.6). There was no evidence for an association with total anomalous pulmonary venous return (no cases with carbamazepine exposure), cleft lip (with or without palate) (0.2, 0.0 to 1.3), diaphragmatic hernia (0.9, 0.1 to 6.6), or hypospadias (0.7, 0.3 to 1.6) compared with no exposure to antiepileptic drugs. Further exploratory analysis suggested a higher risk of single ventricle and atrioventricular septal defect. CONCLUSION: Carbamazepine teratogenicity is relatively specific to spina bifida, though the risk is less than with valproic acid. Despite the large dataset, there was not enough power to detect moderate risks for some rare major congenital malformations.

Epidémiologie et prévention du mélanome cutané en Suisse. [Epidemiology and prevention of melanoma in Switzerland].

[Quintessence] - L'incidence du mélanome malin augmente rapidement depuis plus de 50 ans. - La Suisse, avec 1700 nouveaux cas diagnostiqués par an, est, avec la Norvège, le pays d'Europe le plus touché par le mélanome. - Des différences régionales sont récemment apparues avec une incidence plus élevée dans les cantons romands. - Les changements observés en Suisse dans l'attitude et le comportement face au soleil sont trop récents et modestes pour influencer l'incidence. - La détection précoce effectuée depuis près de 20 ans a permis d'augmenter la survie et le taux de mélanomes fins sans toutefois altérer l'incidence des lésions épaisses. - La mortalité associée au mélanome malin a récemment diminué, d'abord chez les femmes. L'efficacité de la prévention devrait se confirmer à terme si les efforts entrepris se poursuivent. [Auteurs] [Summary] - The incidence of malignant melanoma has steadily increased in Caucasian populations over the last 50 years. - With some 1700 new cases per year, Switzerland has, with Norway, the highest rate of melanoma in Europe. - Regional differences within Switzerland are emerging, with a higher incidence in western (French-speaking) cantons. - Observed changes in sun protection attitudes and knowledge in the Swiss population have yet to impact on the incidence trend. - Early detection, as pursued since the mid-1980s in Switzerland, has led to a substantial increase in survival and rates of thin melanoma, without major change in rates of thick melanoma. - Mortality from melanoma has recently decreased, initially in women. The effectiveness of prevention campaigns should eventually be confirmed if current efforts persist. [Authors]

Genetic association tests: a method for the joint analysis of family and case-control data.

With the trend in molecular epidemiology towards both genome-wide association studies and complex modelling, the need for large sample sizes to detect small effects and to allow for the estimation of many parameters within a model continues to increase. Unfortunately, most methods of association analysis have been restricted to either a family-based or a case-control design, resulting in the lack of synthesis of data from multiple studies. Transmission disequilibrium-type methods for detecting linkage disequilibrium from family data were developed as an effective way of preventing the detection of association due to population stratification. Because these methods condition on parental genotype, however, they have precluded the joint analysis of family and case-control data, although methods for case-control data may not protect against population stratification and do not allow for familial correlations. We present here an extension of a family-based association analysis method for continuous traits that will simultaneously test for, and if necessary control for, population stratification. We further extend this method to analyse binary traits (and therefore family and case-control data together) and accurately to estimate genetic effects in the population, even when using an ascertained family sample. Finally, we present the power of this binary extension for both family-only and joint family and case-control data, and demonstrate the accuracy of the association parameter and variance components in an ascertained family sample.

Epidemiologie und Prävention des Hautmelanoms in der Schweiz: Update 2010. [Epidemiology and prevention of melanoma in Switzerland: 2010 update]

Zusammenfassung] Die Inzidenz des malignen Melanoms steigt seit über 50 Jahren bei der weißen Bevölkerung stark an. Die Schweiz ist mit ungefähr 1900 neu diagnostizierten Fällen pro Jahr das am stärksten betroffene Land Europas (16/100 000 Welt-standardisierte Rate). In letzter Zeit sind regionale Unterschiede mit höherer Inzidenz in den Westschweizer Kantonen festzustellen. Änderungen in Wissen und Verhalten der Schweizer Bevölkerung gegenüber dem Schutz vor Sonnenexposition bestehen noch zu wenig lange und sind zu bescheiden, als dass sie schon einen Einfluss auf die Inzidenz hätten haben können. Dank der seit 20 Jahren betriebenen Früherfassung sind Überlebensrate und Anteil an dünnen Melanomen gestiegen, allerdings bei gleichbleibender Inzidenz dicker Läsionen. Die Mortalität aufgrund des malignen Melanoms ist neuerdings rückläufig, vor allem bei den Frauen. Werden die gegenwärtigen Präventionsbemühungen weitergeführt, dürften sich bald noch mehr Erfolge zeigen. [Abstract] The incidence of cutaneous malignant melanoma has steadily increased in Caucasian populations over the last decades. With around 1900 new cases each year, Switzerland has one of the highest melanoma rates in Europe (16/100 000 world-standardised rate). Regional differences are emerging within Switzerland, with a higher incidence in the western (French-speaking) region. Observed changes in sun protection attitudes and knowledge in the Swiss population have yet no impact on the incidence trend. Early detection, carried out since the mid 1980s in Switzerland, has led to a substantial increase in survival and rates of thin melanoma, without material change in rates of thick melanoma. Mortality from melanoma has recently decreased, earlier in women than men. The efficacy of prevention campaigns should soon become more blatant if current efforts persist.

Home Blood Pressure Measurement – Epidemiology and Clinical Application

Verenpaineen kotimittaus − epidemiologia ja kliininen käyttö Kohonnutta verenpainetta, maailmanlaajuisesti merkittävintä ennenaikaiselle kuolemalle altistavaa riskitekijää, ei voida tunnistaa tai hoitaa ilman tarkkoja ja käytännöllisiä verenpaineen mittausmenetelmiä. Verenpaineen kotimittaus on saavuttanut suuren suosion potilaiden keskuudessa. Lääkärit eivät ole kuitenkaan vielä täysin hyväksyneet verenpaineen kotimittausta, sillä riittävä todistusaineisto sen toimivuudesta ja eduista on puuttunut. Tämän tutkimuksen tarkoituksena oli osoittaa, että kotona mitattu verenpaine (kotipaine) on perinteistä vastaanotolla mitattua verenpainetta (vastaanottopaine) tarkempi, ja että se on tehokas myös kliinisessä käytössä. Tutkimme kotipaineen käyttöä verenpainetaudin diagnosoinnissa ja hoidossa. Lisäksi tarkastelimme kotipaineen yhteyttä verenpainetaudin aiheuttamiin kohde-elinvaurioihin. Ensimmäinen aineisto, joka oli edustava otos Suomen aikuisväestöstä, koostui 2 120 45–74-vuotiaasta tutkimushenkilöstä. Tutkittavat mittasivat kotipainettaan viikon ajan ja osallistuivat terveystarkastukseen, johon sisältyi kliinisen tutkimuksen ja haastattelun lisäksi sydänfilmin otto ja vastaanottopaineen mittaus. 758 tutkittavalle suoritettiin lisäksi kaulavaltimon seinämän intima-mediakerroksen paksuuden (valtimonkovettumataudin mittari) mittaus ja 237:lle valtimon pulssiaallon nopeuden (valtimojäykkyyden mittari) mittaus. Toisessa aineistossa, joka koostui 98 verenpainetautia sairastavasta potilaasta, hoitoa ohjattiin satunnaistamisesta riippuen joko ambulatorisen eli vuorokausirekisteröinnillä mitatun verenpaineen tai kotipaineen perusteella. Vastaanottopaine oli kotipainetta merkittävästi korkeampi (systolisen/diastolisen paineen keskiarvoero oli 8/3 mmHg) ja yksimielisyys verenpainetaudin diagnoosissa kahden menetelmän välillä oli korkeintaan kohtalainen (75 %). 593 tutkittavasta, joilla oli kohonnut verenpaine vastaanotolla, 38 %:lla oli normaali verenpaine kotona eli ns. valkotakkiverenpaine. Verenpainetauti voidaan siis ylidiagnosoida joka kolmannella potilaalla seulontatilanteessa. Valkotakkiverenpaine oli yhteydessä lievästi kohonneeseen verenpaineeseen, matalaan painoindeksiin ja tupakoimattomuuteen, muttei psykiatriseen sairastavuuteen. Valkotakkiverenpaine ei kuitenkaan vaikuttaisi olevan täysin vaaraton ilmiö ja voi ennustaa tulevaa verenpainetautia, sillä siitä kärsivien sydän- ja verisuonitautien riskitekijäprofiili oli normaalipaineisten ja todellisten verenpainetautisten riskitekijäprofiilien välissä. Kotipaineella oli vastaanottopainetta vahvempi yhteys verenpainetaudin aiheuttamiin kohde-elinvaurioihin (intima-mediakerroksen paksuus, pulssiaallon nopeus ja sydänfilmistä todettu vasemman kammion suureneminen). Kotipaine oli tehokas verenpainetaudin hoidon ohjaaja, sillä kotipaineeseen ja ambulatoriseen paineeseen, jota on pidetty verenpainemittauksen ”kultaisena standardina”, perustuva lääkehoidon ohjaus johti yhtä hyvään verenpaineen hallintaan. Tämän ja aikaisempien tutkimusten tulosten pohjalta voidaan todeta, että verenpaineen kotimittaus on selkeä parannus perinteiseen vastaanotolla tapahtuvaan verenpainemittaukseen verrattuna. Verenpaineen kotimittaus on käytännöllinen, tarkka ja laajasti saatavilla oleva menetelmä, josta voi tulla jopa ensisijainen vaihtoehto verenpainetautia diagnosoitaessa ja hoitaessa. Verenpaineen mittauskäytäntöön tarvitaan muutos, sillä näyttöön perustuvan lääketieteen perusteella vaikuttaa, että vastaanotolla tapahtuvaa verenpainemittausta tulisi käyttää vain seulontatarkoitukseen.

The state of veterinary epidemiology and economics

Recent developments in the fields of veterinary epidemiology and economics are critically reviewed and assessed. The impacts of recent technological developments in diagnosis, genetic characterisation, data processing and statistical analysis are evaluated. It is concluded that the acquisition and availability of data remains the principal constraint to the application of available techniques in veterinary epidemiology and economics, especially at population level. As more commercial producers use computerised management systems, the availability of data for analysis within herds is improving. However, consistency of recording and diagnosis remains problematic. Recent trends to the development of national livestock databases intended to provide reassurance to consumers of the safety and traceability of livestock products are potentially valuable sources of data that could lead to much more effective application of veterinary epidemiology and economics. These opportunities will be greatly enhanced if data from different sources, such as movement recording, official animal health programmes, quality assurance schemes, production recording and breed societies can be integrated. However, in order to realise such integrated databases, it will be necessary to provide absolute control of user access to guarantee data security and confidentiality. The potential applications of integrated livestock databases in analysis, modelling, decision-support, and providing management information for veterinary services and livestock producers are discussed. (c) 2004 Elsevier B.V. All rights reserved.

Speed sensorless vector control of induction machines

A novel rotor velocity estimation scheme applicable to vector controlled induction motors has been described. The proposed method will evaluate rotor velocity, ωr, on-line, does not require any extra transducers or injection of any signals, nor does it employ complicated algorithms such as MRAS or Kalman filters. Furthermore, the new scheme will operate at all velocities including zero with very little error. The procedure employs motor model equations, however all differential and integral terms have been eliminated giving a very fast, low-cost, effective and practical alternative to the current available methods. Simulation results verify the operation of the scheme under ideal and PWM conditions.

Transcriptional regulators of the GAD acid stress island are carried by effector protein-encoding prophages and indirectly control type III secretion in enterohemorrhagic Escherichia coli O157:H7

P>Type III secretion (T3S) plays a pivotal role in the colonization of ruminant hosts by Enterohemorrhagic Escherichia coli (EHEC). The T3S system translocates effector proteins into host cells to promote bacterial attachment and persistence. The repertoire and variation in prophage regions underpins differences in the pathogenesis and epidemiology of EHEC strains. In this study, we have used a collection of deletions in cryptic prophages and EHEC O157 O-islands to screen for novel regulators of T3S. Using this approach we have identified a family of homologous AraC-like regulators that indirectly repress T3S. These prophage-encoded secretion regulator genes (psr) are found exclusively on prophages and are associated with effector loci and the T3S activating Pch family of regulators. Transcriptional profiling, mutagenesis and DNA binding studies were used to show that these regulators usurp the conserved GAD acid stress resistance system to regulate T3S by increasing the expression of GadE (YhiE) and YhiF and that this regulation follows attachment to bovine epithelial cells. We further demonstrate that PsrA and effectors encoded within cryptic prophage CP933-N are required for persistence in a ruminant model of colonization.

Assessing the effects of vector control on dengue transmission

The dengue virus is an arbovirus transmitted to humans through mosquito Aedes aegypti. To describe the dynamics of dengue disease within these two populations we develop a compartment model taking into account chemical controls and mechanical control applied on the mosquitoes, which are the currently available controlling mechanisms to prevent dengue disease. To mimic seasonal variations, some parameters of the model are allowed to depend on time in order to divide a calendar year in favorable and unfavorable periods regarded to the development of vector population. (c) 2007 Elsevier B.V. All rights reserved.

On an acute case of Chagas disease in a region under vector control in the state of São Paulo, Brazil

Desde a década de 1970 não se notificavam casos autóctones de doença de Chagas aguda em São Paulo. em março de 2006 a Vigilância Epidemiológica registrou óbito por doença de Chagas aguda, em Itaporanga, de paciente de seis anos de idade. Exame histopatológico post mortem realizado no Hospital das Clínicas da Faculdade de Medicina de Botucatu confirmou o diagnóstico. Consultamos prontuários de hospitais e entrevistamos profissionais de saúde envolvidos além de familiares do paciente. Descrevemos medidas adotadas in loco para identificar a via de transmissão, reservatórios e vetores. Discutimos as possíveis fontes de infecção. Na região não foram identificados outros casos humanos, vetores ou reservatórios vertebrados infectados por Trypanosoma cruzi. Salientamos a importância de manter a vigilância, mesmo em áreas onde a transmissão de doença de Chagas está interrompida e naquelas ainda infestadas por triatomíneos. Deve-se admitir a hipótese diagnóstica de doença de Chagas quando observados: edema palpebral (uni ou bilateral), insuficiência cardíaca, miocardite, pericardite, anasarca, quadros similares aos de síndrome nefrótica ou glomerulonefrite sem causas outras aparentes, em pacientes com dados epidemiológicos positivos. Encontro, mesmo em raras ocasiões, de triatomíneos na região ou ainda contato com alimento contaminável com formas infectantes de T. cruzi.

A comparative analysis of the relative efficacy of vector-control strategies against dengue fever

Dengue is considered one of the most important vector-borne infection, affecting almost half of the world population with 50 to 100 million cases every year. In this paper, we present one of the simplest models that can encapsulate all the important variables related to vector control of dengue fever. The model considers the human population, the adult mosquito population and the population of immature stages, which includes eggs, larvae and pupae. The model also considers the vertical transmission of dengue in the mosquitoes and the seasonal variation in the mosquito population. From this basic model describing the dynamics of dengue infection, we deduce thresholds for avoiding the introduction of the disease and for the elimination of the disease. In particular, we deduce a Basic Reproduction Number for dengue that includes parameters related to the immature stages of the mosquito. By neglecting seasonal variation, we calculate the equilibrium values of the model’s variables. We also present a sensitivity analysis of the impact of four vector-control strategies on the Basic Reproduction Number, on the Force of Infection and on the human prevalence of dengue. Each of the strategies was studied separately from the others. The analysis presented allows us to conclude that of the available vector control strategies, adulticide application is the most effective, followed by the reduction of the exposure to mosquito bites, locating and destroying breeding places and, finally, larvicides. Current vector-control methods are concentrated on mechanical destruction of mosquitoes’ breeding places. Our results suggest that reducing the contact between vector and hosts (biting rates) is as efficient as the logistically difficult but very efficient adult mosquito’s control.