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Working in the port of Amoy (now known as the port of Xiamen), China (1-5), Sir Patrick Manson noted that Wuchereria bancrofti microfilariae appeared with marked periodicity in the blood [...]

* Viral Interference between Respiratory Viruses * Novel Clinical Monitoring Approaches for Reemergence of Diphtheria Myocarditis, Vietnam * Clinical and Laboratory Characteristics and Outcome of Illness Caused by Tick-Borne Encephalitis [...]

* Viral Interference between Respiratory Viruses * Novel Clinical Monitoring Approaches for Reemergence of Diphtheria Myocarditis, Vietnam * Clinical and Laboratory Characteristics and Outcome of Illness Caused by Tick-Borne Encephalitis [...]

* Viral Interference between Respiratory Viruses * Novel Clinical Monitoring Approaches for Reemergence of Diphtheria Myocarditis, Vietnam * Clinical and Laboratory Characteristics and Outcome of Illness Caused by Tick-Borne Encephalitis [...]

* Viral Interference between Respiratory Viruses * Novel Clinical Monitoring Approaches for Reemergence of Diphtheria Myocarditis, Vietnam * Clinical and Laboratory Characteristics and Outcome of Illness Caused by Tick-Borne Encephalitis [...]

To satisfy the growing demand for electricity, Ethiopia plans to increase its electricity production five-fold between 2010 and 2015, mainly through the construction of dams. A literature review shows that while dams can boost power and agricultural production, promote economic development, and facilitate flood control, they can also lead to environmental, ecological, and socioeconomic changes. Several case studies show that dams may alter the composition and density of vectors and intermediate host species, increase the incidence of malaria schistosomiasis and possibly lymphatic filariasis, and lead to eutrophication of reservoirs, soil erosion, and earthquakes. There is evidence that dams and commercial irrigation schemes can increase soil and water degradation, vulnerability to drought, and food insecurity in riverine and lacustrine areas downstream of dams. It appears that dams in Ethiopia are also vulnerable to high soil erosion rates and earthquakes. Consequently, the current and proposed large-scale dam construction program in Ethiopia requires in-depth research to improve our understanding of the unintended negative effects of projects and to guide the location, design, and implementation of appropriate preventive and remedial programs. Key words: water resource developments, environment, food security, vector-borne diseases, Ethiopia. Les auteurs presentent une revue de litterature montrant qu'en depit du fait que les barrages peuvent favoriser les productions d'energetiques et agricoles, promouvoir le developpement economique et faciliter la maitrise des inondations, ils peuvent egalement provoquer des changements environnementaux, ecologiques et socio-economiques. Plusieurs etudes de cas montrent que les barrages peuvent modifier la composition et la densite d'especes hotes vectrices et intermediaires, augmenter l'incidence de la schistosomiase de la malaria et possiblement la filariose lymphatique, en plus de conduire a l'eutrophisation des reservoirs, a l'erosion du sol et aux tremblements de terre. Il y a des preuves a l'effet que les barrages et les systemes d'irrigation commerciaux peuvent augmenter la degradation de l'eau et des sols, la vulnerabilite a la secheresse et l'insecurite alimentaire dans les regions riveraines et lacustres en aval des barrages. Il semble que les barrages en Ethiopie seraient egalement vulnerables a des taux eleves d'erosion du sol et aux tremblements de terre. Consequemment, le programme actuel de construction de barrages a grande echelle en Ethiopie necessite des recherches approfondies afin d'ameliorer notre comprehension des effets negatifs collateraux des projets et de guider la localisation, la conception et la mise en place de programmes de prevention et de remediation. Mots-cles: developpement des ressources hydrauliques, environnement, securite alimentaire, maladies transmises par vecteurs, Ethiopie., Background Only 15% of the Ethiopian population has access to the national electricity network. This low percentage is due to inadequate power generation and electricity distribution. Approximately 80% of Ethiopians [...]

* Childcare Exposure to Severe Acute Respiratory Syndrome Coronavirus 2 for 4-Year-Old Presymptomatic Child, South Korea * Characteristics of Patients Co-infected with Severe Acute Respiratory Syndrome Coronavirus 2 and Dengue [...]

In 2006, several southern states in India reported outbreaks of chikungunya. In the metropolis of Chennai, the first laboratory-confirmed chikungunya cases had an onset of symptoms at the end of May 2006. The authors reviewed surveillance data in which a suspected case of chikungunya was defined as a patient presenting with fever and arthralgia at a medical camp in Chennai on and after June 20, 2006. Over the same period, the authors reviewed surveillance data and larval indices for the vector Aedes aegypti. From June 20 to October 10, 2006, they reported 4,760 suspected cases of chikungunya (attack rate of 0.1%, no fatalities). Control measures included removal of breeding sites, daytime fogging against adult mosquitoes, and information campaigns. The early detection and effective prevention of future outbreaks rely on strengthened human and entomological surveillance, participation of private medical practitioners in case reporting, and community involvement to reduce potential breeding sites of the vector., Introduction Chikungunya is a viral disease transmitted by the bite of an infected Aedes mosquito. The disease usually presents with sudden onset of fever and is characterized by arthralgia (joint [...]

A systematic functional analysis across much of the conventional Anopheles gambiae odorant receptor (AgOR) repertoire was carried out in Xenopus oocytes using two-electrode, voltage-clamp electrophysiology. The resulting data indicate that each AgOR manifests a distinct odor-response profile and tuning breadth. The large diversity of tuning responses ranges from AgORs that are responsive to a single or small number of odorants (specialists) to more broadly tuned receptors (generalists). Several AgORs were identified that respond robustly to a range of human volatiles that may play a critical role in anopheline host selection. AgOR responses were analyzed further by constructing a multidimensional odor space representing the relationships between odorants and AgOR responses. Within this space, the distance between odorants is related to both chemical class and concentration and may correlate with olfactory discrimination. This study provides a comprehensive overview of olfactory coding mechanisms of An. gambiae that ultimately may aid in fostering the design and development of olfactory-based strategies for reducing the transmission of malaria and other mosquito-borne diseases. odorant receptor | olfaction doi/10.1073/pnas.0913392107

Objective Novel, inexpensive solutions are needed for improved management of vector-borne and other diseases in resource-poor environments. Emerging free software providing access to satellite imagery and simple editing tools (e.g. Google Earth[TM]) complement existing geographic information system (GIS) software and provide new opportunities for: (i) strengthening overall public health capacity through development of information for city infrastructures; anal (ii) display of public health data directly on an image of the physical environment. Methods We used freely accessible satellite imagery and a set of feature-making tools included in the software (allowing for production of polygons, lines and points) to generate information for city infrastructure anal to display disease data in a dengue decision support system (DDSS) framework. Findings Two cities in Mexico (Chetumal and Merida) were used to demonstrate that a basic representation of city infrastructure useful as a spatial backbone in a DDSS can be rapidly developed at minimal cost. Data layers generated included labelled polygons representing city blocks, lines representing streets, and points showing the locations of schools and health clinics. City blocks were colour-coded to show presence of dengue cases. The data layers were successfully imported in a format known as shapefile into a GIS software. Conclusion The combination of Google Earth[TM] and free GIS software (e.g. HealthMapper, developed by WHO, and SIGEpi, developed by PAHO) has tremendous potential to strengthen overall public health capacity anal facilitate decision support system approaches to prevention and control of vector-borne diseases in resource-poor environments. Objectif Des solutions innovantes et peu onereuses sont necessaires pour ameliorer la prise en charge des maladies a transmission vectorielle et autres dans les environnements pauvres en ressources. Les logiciels emergents gratuits qui fournissent un acces a l'imagerie sateilitaire et a des outils d'edition simples (Google Earth[TM]) completent les logiciels de systeme d'information geographique (GIS) et offrent de nouvelles possibilites : (i) de renforcer les capacites globales de la sante publique par la generation d'informations concernant les infrastructures urbaines; et (ii) d'afficher directement des donnees de sante publique sur une image de l'environnement physique. Methodes Nous avons utilise l'imagerie satellitaire en acces libre et une serie d'outils de tracage appartenant au logiciel (permettant de produire des polygones, des lignes et des points) pour generer des informations sur l'infrastructure urbaine et pour afficher des donnees de morbidite dans le cadre d'un systeme d'aide a la decision concernant la dengue (DDSS). Resultats Nous nous sommes servis de deux villes du Mexique (Chetumal et Merida) pour demontrer qu'il etait possible de developper rapidement et a un cout minimal une representation rudimentaire des infrastructures urbaines, utilisable comme epine dorsale spatiale d'un DDSS. Les couches de donnees generees comprenaient des polygones etiquetes representant des pates de maisons, des lignes figurant des rues et des points indiquant l'emplacement d'ecoles et de centres de sante. Les pates de maisons ont ete colores selon un code de maniere a signaler la presence de cas de dengue. Ces couches de donnees ont ete importees avec succes sous un format appele fichier de formes dans un logiciel GIS. Conclusion La combinaison associant Google Earth[TM] et un logiciel GIS libre et gratuit (par exemple HealthMapper, developpe par l'OMS, ou SIGEpi, developpe par l'OPS) offre un enorme potentiel pour renforcer les capacites generales de la sante publique et faciliter l'utilisation de systemes d'aide a la decision pour prevenir et combattre les maladies a transmission vectorielle dans les environnements pauvres en ressources. Objetivo Se necesitan soluciones novedosas y de bajo costo para mejorar la gestion de las enfermedades de transmision vectorial y de otro tipo en los entornos con recursos escasos. Las nuevas opciones de software gratuito que dan acceso a imagenes por satelite y a instrumentos de edicion sencillos (por ejemplo Google Earth[TM]) complementan el software del sistema de informacion geografica (SIG) existente y brindan nuevas oportunidades para: (i) reforzar la capacidad global de salud publica mediante la elaboracion de informacion para infraestructuras urbanas; y (ii) mostrar los datos de salud publica directamente en una imagen del entorno fisico. Metodos Se utilizaron imagenes por satelite de libre acceso y una serie de prestaciones de generacion de detalles incluidas en el software (que permiten crear poligonos, lineas y puntos) para anadir informacion sobre las infraestructuras urbanas y representar datos sobre las enfermedades en el marco de un sistema de apoyo decisional para el dengue (DDSS). Resultados Se utilizaron dos ciudades de Mexico (Chetumal y Merida) para demostrar que es posible desarrollar rapidamente y con un costo minimo una representacion basica de la infraestructura urbana que revista utilidad como urdimbre espacial en un DDSS. Las capas de informacion generadas comprendian poligonos etiquetados que representaban cuadras, lineas que reproducian las calles, y puntos que indicaban la localizacion de las escuelas y los dispensarios. Las cuadras se codificaron mediante colores en funcion de los casos de dengue. Las capas de informacion se pudieron importar satisfactoriamente a un software SIG en el formato conocido como shapefiles. Conclusion La combinacion de Google Earth[TM] y software SIG gratuito (por ejempio, HealthMapper, desarrollado por la OMS, y SIGEpi, desarrollado por la OPS) brinda enormes posibilidades para reforzar la capacidad general de salud publica y facilitar la aplicacion de sistemas de apoyo decisional a la prevencion y el control de enfermedades de transmision vectorial en los entornos con recursos escasos., Introduction Vector-borne diseases inflict a terrible and unacceptable public health burden in developing countries. Indeed, seven of the 10 diseases targeted by the WHO Special Programme for Research and Training [...]

The vector-borne bacterium Borrelia hermsii, a relapsing fever agent, switches gene expression of a surface protein between different antigenic variants, thereby causing sequential waves of immune escape within hosts and increasing the likelihood of transmission. Analogous programmed systems of antigenic variation occur in African trypanosomes and Plasmodium falciparum. In these examples, switch rates to individual variants differ over a wide range. We studied how B. hermsii determines switch rates in two experimental infections: one where variants were identified by specific antisera and one based on identification by DNA sequence. Unexpressed loci of variant antigens copy into a single expression site at rates determined by extragenic features of silent loci rather than similarity between coding sequences of variants at silent sites and the single expression site. Two elements, in particular, determine switch rates. One set of elements overlaps the 5' ends of the expressed gene and the silent loci; greater sequence identity between elements was associated with a higher switch rate. The second set of elements flanks the expression site on the 3' side and occurs at variable distances downstream from silent loci; the nearer an element to a silent locus, the greater the switch rate of that locus into the expression site. In combination, these two features of the genome provide a simple mechanism to modulate switch rate whereby silent loci form a hierarchy of switch rates into the expression site. Although the switching hierarchy causes changes in individual cells that are stochastic, ordering of variants within hosts is semipredictable. antibody | Borrelia | recombination | relapsing fever | vector-borne

Yersinia pestis is transmitted by fleas and causes bubonic plague, characterized by severe local lymphadenitis that progresses rapidly to systemic infection and life-threatening septicemia. Here, we show that although flea-borne transmission usually leads to bubonic plague in mice, it can also lead to primary septicemic plague. However, intradermal injection of Y. pestis, commonly used to mimic transmission by fleabite, leads only to bubonic plague. A Y. pestis strain lacking the plasmid-encoded cell-surface plasminogen activator, which is avirulent by intradermal or s.c. injection, was able to cause fatal primary septicemic plague at low incidence, but not bubonic plague, when transmitted by fleas. The results clarify a Iong-standing uncertainty about the etiology of primary septicemic plague and support an evolutionary scenario in which plague first emerged as a flea-borne septicemic disease of limited transmissibility. Subsequent acquisition of the plasminogen activator gene by horizontal transfer enabled the bubonic form of disease and increased the potential for epidemic spread. vector-borne disease

To the Editor: In autumn 2011, an unidentified disease of livestock was reported on both sides of the Dutch-Germany border. By using metagenomics, the etiologic agent of this disease was [...]

The nature of Xylella fastidiosa-vector interactions is determined by using biochemical, molecular and biological assays. The studies have shown that Xylella fastidiosa colonization of leafhopper vectors is a complex, stepwise process that is similar to the formation of biofilms on surfaces.

Shuttle vectors that replicate stably and express selectable phenotypes in both Thermococcus kodakaraensis and Escherichia coli are constructed. Affinity purification has confirmed that an hemagglutinin (HA)- plus six-histidine-tagged RpoL subunit (RpoL-HA-[his.sub.6]) synthesized ectopically from a shuttle vector is assembled in vivo into RNA polymerase (RNAP) holoenzymes that are active and is purified directly from Thermococcus kodakaraensis cell lysates by [Ni.sup.2+] binding and imidazole elution.

Research on the Dalton Highway in Alaska indicates that road maintenance, vehicles of vertebrate vectors drawn to the highway foster snail or trematode colonization. Implications for studying how roads impact disease transmission are discussed.

This year is on track to be the worst on record for West Nile virus in the United States. As of 11 September, more than 2,600 new cases, including 118 [...]

American Scientist magazine has awarded North Carolina State University researchers Fred Gould, Krisztian Magori and Yunxin Huang its first George Bugliarello Prize for their article on 'Genetic Strategies for Controlling […]