Dengue — Quo tu et quo vadis?

Dengue viruses (DENV) are by far the most important arboviral pathogens in the tropics around the world, putting at risk of infection nearly a third of the global human population. DENV are members of the genus Flavivirus in the Family Flaviviridae and comprise four antigenically distinct serotypes (DENV-1-4). Although they share almost identical epidemiological features, they are genetically distinct. Phylogenetic analyses have revealed valuable insights into the origins, epidemiology and the forces that shape DENV evolution in nature. In this review, we examine the current status of DENV evolution, including but not limited to rates of evolution, selection pressures, population sizes and evolutionary constraints, and we discuss how these factors influence transmission, pathogenesis and emergence

On Channel Sharing Policies in LEO Mobile Satellite Systems

We consider a low earth orbit (LEO) mobile satellite system with "satellite-fixed" cells that accommodates new and handover calls of different service-classes. We provide an analytical framework for the efficient calculation of call blocking and handover failure probabilities under two channel sharing policies, namely the fixed channel reservation and the threshold call admission policies. Simulation results verify the accuracy of the proposed formulas. Furthermore, we discuss the applicability of the policies in software-defined LEO satellites

An analytical framework in LEO mobile satellite systems servicing batched Poisson traffic

The authors consider a low earth orbit (LEO) mobile satellite system (MSS) that accepts new and handover calls of multirate service-classes. New calls arrive in the system as batches, following the batched Poisson process. A batch has a generally distributed number of calls. Each call is treated separately from the others and its acceptance is decided according to the availability of the requested number of channels. Handover calls follow also a batched Poisson process. All calls compete for the available channels under the complete sharing policy. By considering the LEO-MSS as a multirate loss system with ‘satellite-fixed’ cells, it can be analysed via a multi-dimensional Markov chain, which yields to a product form solution (PFS) for the steady-state distribution. Based on the PFS, they propose a recursive and yet efficient formula for the determination of the channel occupancy distribution, and consequently, for the calculation of various performance measures including call blocking and handover failure probabilities. The latter are much higher compared to the corresponding probabilities in the case of the classical (and less bursty) Poisson process. Simulation results verify the accuracy of the proposed formulas. Furthermore, they discuss the applicability of the proposed model in software-defined LEO-MSS

Sylvatic Dengue Virus Type 2 Activity in Humans, Nigeria, 1966

Using phylogenetic analysis of complete virus genomes from human isolates obtained in Nigeria in 1966, we identified sylvatic dengue virus (DENV) strains from 3 febrile patients. This finding extends current understanding of the role of sylvatic DENV in febrile disease and documents another focus of sylvatic DENV transmission in West Africa

Enabling Practices for Information Systems Adoption in the Complex Context of Greek E-Government

The Greek administrative context is characterized by a centralized and bureaucratic culture and is heavily influenced by the ongoing financial crisis. E-government is under development and remains greatly fragmented while adoption is low and resistance by public agencies and citizens is often high. Against this background, this paper provides an in-depth study of four nation-wide e-government projects recently adopted in Greece that were successfully implemented and widely adopted by their intended stakeholders. The study of these projects reveals common enabling factors. Based on our find-ings, we propose a framework that links together three enabling practices for the adoption of e-government projects, namely, top-down pressures, agency ownership and user engagement. We dis-cuss how these are interrelated and their implications for improving e-government adoption ‘against the odds’

The Coordinating Research on Emerging Arboviral Threats Encompassing the Neotropics (CREATE-NEO)

Arthropod-borne viruses, such as dengue, Zika, and Mayaro, are emerging at an accelerating rate in the neotropics. The C oordinating R esearch on E merging A rboviral T hreats E ncompassing the Neo tropics (CREATE-NEO) project, a part of the NIH-funded Centers for Research in Emerging Infectious Diseases (CREID) network provides a nimble and flexible network of surveillance sites in Central and South America coupled with cutting-edge modeling approaches to anticipate and counter these threats to public health. Collected data and generated models will be utilized to inform and alert local, regional, and global public health agencies of enzootic arboviruses with a high risk of spillover, emergence, and transmission among humans, and/or international spread. CREATE-NEO builds capacity in situ to anticipate, detect, and respond to emerging arboviruses at the point of origin, thereby maximizing the potential to avert full-blown emergence and widespread epidemics

The Family \u3cem\u3eRhabdoviridae\u3c/em\u3e: Mono- and Bipartite Negative-Sense RNA Viruses with Diverse Genome Organization and Common Evolutionary Origins

The family Rhabdoviridae consists of mostly enveloped, bullet-shaped or bacilliform viruses with a negative-sense, single-stranded RNA genome that infect vertebrates, invertebrates or plants. This ecological diversity is reflected by the diversity and complexity of their genomes. Five canonical structural protein genes are conserved in all rhabdoviruses, but may be overprinted, overlapped or interspersed with several novel and diverse accessory genes. This review gives an overview of the characteristics and diversity of rhabdoviruses, their taxonomic classification, replication mechanism, properties of classical rhabdoviruses such as rabies virus and rhabdoviruses with complex genomes, rhabdoviruses infecting aquatic species, and plant rhabdoviruses with both mono- and bipartite genomes

Genomes of viral isolates derived from different mosquitos species

Eleven viral isolates derived mostly in albopictus C6/36 cells from mosquito pools collected in Southeast Asia and the Americas between 1966 and 2014 contained particles with electron microscopy morphology typical of reoviruses. Metagenomics analysis yielded the near complete genomes of three novel reoviruses, Big Cypress orbivirus, Ninarumi virus, and High Island virus and a new tetravirus, Sarawak virus. Strains of previously characterized Sathuvarachi, Yunnan, Banna and Parry's Lagoon viruses (Reoviridae), Bontang virus (Mesoniviridae), and Culex theileri flavivirus (Flaviviridae) were also characterized. The availability of these mosquito virus genomes will facilitate their detection by metagenomics or PCR to better determine their geographic range, extent of host tropism, and possible association with arthropod or vertebrate disease.Peer reviewe