Neurovirulent flavivirus can be attenuated in mice by incorporation of neuron-specific microRNA recognition elements into viral genome.Engineering viruses by inserting microRNA (miRNA) recognition elements (MREs) into the 3'-untranslated region (3'-UTR) of viral RNA can efficiently restrict viral tissue tropism. We used the mosquito-borne Japanese encephalitis virus (JEV) to investigate whether endogenous neuron-specific microRNA-124 (miR-124) could be used to restrict viral neurotropism and, consequently, diminish the neurovirulence of JEV in mice. To recover a neuron-restricted JEV, we inserted 2 copies of a perfectly matched ...201122008823
west nile virus: north american experience.west nile virus, a mosquito-vectored flavivirus of the japanese encephalitis serogroup, was first detected in north america following an epizootic in the new york city area in 1999. in the intervening 11 years since the arrival of the virus in north america, it has crossed the contiguous usa, entered the canadian provinces bordering the usa, and has been reported in the caribbean islands, mexico, central america and, more recently, south america. west nile virus has been reported in over 300 spe ...201121910847
rhabdomyolysis and severe muscular weakness in a traveler diagnosed with alkhurma hemorrhagic fever virus infection.alkhurma hemorrhagic fever virus (ahfv) is a tick-borne flavivirus with high case fatality rates, endemic in the arabian peninsula. recently ahfv was detected in travelers returning from egypt suggesting geographical spreading. we also report ahfv infection in a traveler ex egypt, representing atypical symptoms of rhabdomyolysis and severe muscular weakness.201121889906
quinoline tricyclic derivatives. design, synthesis and evaluation of the antiviral activity of three new classes of rna-dependent rna polymerase this study three new classes of linear n-tricyclic compounds, derived by condensation of the quinoline nucleus with 1,2,3-triazole, imidazole or pyrazine, were synthesized, obtaining triazolo[4,5-g]quinolines, imidazo[4,5-g]quinolines and pyrido[2,3-g]quinoxalines, respectively. title compounds were tested in cell-based assays for cytotoxicity and antiviral activity against rna viruses representative of the three genera of the flaviviridae family, that is bvdv (pestivirus), yfv (flavivirus) a ...201122047799
West Nile virus: immunity and pathogenesis.West Nile virus (WNV) is a neurotropic, arthropod-borne flavivirus that is maintained in an enzootic cycle between mosquitoes and birds, but can also infect and cause disease in horses and humans. WNV is endemic in parts of Africa, Europe, the Middle East, and Asia, and since 1999 has spread to North America, Mexico, South America, and the Caribbean. WNV infects the central nervous system (CNS) and can cause severe disease in a small minority of infected humans, mostly immunocompromised or the e ...201121994755
the first report of west nile virus infection in a child from turkey.seroprevalence data indicate that west nile virus (wnv) activity is present in turkey; however, no pediatric cases of wnv infection have been reported to date. wnv is an emerging flavivirus in turkey, and in september2010, the turkish ministry of health reported the first seven cases of laboratory-confirmed wnv infection from five different cities in the western part of the country. this is the first report of a child from central anatolia, indicating the existence of the virus in other regions ...201121980815
a thiopurine drug inhibits west nile virus production in cell culture, but not in mice.many viruses within the flavivirus genus cause significant disease in humans; however, effective antivirals against these viruses are not currently available. we have previously shown that a thiopurine drug, 6-methylmercaptopurine riboside (6mmpr), inhibits replication of distantly related viruses within the flaviviridae family in cell culture, including bovine viral diarrhea virus and hepatitis c virus replicon. here we further examined the potential antiviral effect of 6mmpr on several diverse ...201122039536
Distinct Humoral and Cellular Immunity Induced by Alternating Prime-boost Vaccination Using Plasmid DNA and Live Viral Vector Vaccines Expressing the E Protein of Dengue Virus Type 2.Dengue virus, which belongs to the Flavivirus genus of the Flaviviridae family, causes fatal dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) with infection risk of 2.5 billion people worldwide. However, approved vaccines are still not available. Here, we explored the immune responses induced by alternating prime-boost vaccination using DNA vaccine, adenovirus, and vaccinia virus expressing E protein of dengue virus type 2 (DenV2).201122194710
composition of the sequence downstream of the dengue virus 5' cyclization sequence (dcs) affects viral rna replication.rna replication of dengue virus (denv) requires an rna-rna mediated circularization of the viral genome, which includes at least three sets of complementary rna sequences on both ends of the genome. the 5' and the 3' untranslated regions form several additional rna elements that are involved in regulation of translation and required for rna replication. communication between the genomic termini results in a structural reorganization of the rna elements, forming a functional rna panhandle structu ...201222137186
Tick-borne encephalitis increasing in Sweden, 2011. 201121968422
Serosurveillance for Japanese encephalitis virus in wild birds captured in Korea.Climate change induced by recent global warming may have a significant impact on vector-borne and zoonotic diseases. For example, the distribution of Japanese encephalitis virus (JEV) has expanded into new regions. We surveyed the levels of hemagglutination-inhibition (HI) antibodies against JEV (Family Flaviviridae, genus Flavivirus) in wild birds captured in Korea. Blood samples were collected from 1,316 wild birds including the following migratory birds: Oceanodroma castro (n = 4), Anas formo ...201122122903
development and application of an antigen capture elisa assay for diagnosis of japanese encephalitis virus in swine, human and mosquito.abstract: background: japanese encephalitis (je) is a serious zoonosis caused by the japanese encephalitis virus (jev) which is a mosquito-borne pathogen of the family flavivirus. however, the application of several developed laboratory methods for the detection of jev antigens or antibodies are limited by their requirements of laboratory operations, skilled technicians and special facilities. results: to develop a method for detecting jev antigen in swine, human, mosquito and other clinical sp ...201222221768
japanese encephalitis virus in culicine mosquitoes (diptera: culicidae) collected at daeseongdong, a village in the demilitarized zone of the republic of total, 22,846 (17,793 culicines and 5,053 anopheles spp.) female mosquitoes were captured by a mosquito magnet trap at daeseongdong, a small village adjacent to the military demarcation line (center of the demilitarized zone) in northern gyeonggi province, republic of korea (rok). culicine mosquitoes were identified to species, placed in pools of up to 30 mosquitoes each, and screened for flavivirus using a sybr green i-based real-time polymerase chain reaction. in total, 51/660 pools positiv ...201122238887
detection of usutu-virus-specific igg in blood donors from northern italy.abstract we developed a novel enzyme-linked immunosorbent assay to detect the specific igg response to usutu virus (usuv) in humans, by evaluating 359 blood donors who were living in northeastern italy. our results demonstrate the presence of an anti-usuv response in 4 subjects with no history of other flavivirus infection.201222217176
monitoring of the west nile virus epidemic in spain between 2010 and 2011.west nile virus (wnv) is a mosquito-transmitted flavivirus recognized as an emerging and re-emerging pathogen in different countries. this study describes the monitoring of the first wnv epidemic in spain between 2010 and 2011. between september and december 2010, 36 outbreaks of wnv in horses were reported in three different provinces of andalusia (southern spain), with no apparent spread outside this area. the temporal distribution and the clinical signs observed during the wnv epidemic in spa ...201122212118
a diagnostic algorithm to serologically differentiate west nile virus from japanese encephalitis virus infections and its validation in field surveillance of poultry and horses.abstract the detection of west nile virus (wnv) in areas endemic for japanese encephalitis virus (jev) is complicated by the extensive serological cross-reactivity between the two viruses. a testing algorithm was developed and employed for the detection of anti-wnv antibody in areas endemic for jev. using this differentiation algorithm, a serological survey of poultry (2004 through 2009) and horses (2007 through 2009) was performed. among 2681 poultry sera, 125 samples were interpreted as bein ...201222217162
west nile virus population genetics and evolution.west nile virus (wnv) (flaviviridae: flavivirus) is transmitted from mosquitoes to birds, but can cause fatal encephalitis in infected humans. since its introduction into north america in new york in 1999, it has spread throughout the western hemisphere. multiple outbreaks have also occurred in europe over the last 20 years. this review highlights recent efforts to understand how host pressures impact viral population genetics, genotypic and phenotypic changes which have occurred in the wnv geno ...201122226703
seroconversion for west nile and st. louis encephalitis viruses among sentinel horses in colombia.we prospectively sampled flavivirus-naïve horses in northern colombia to detect west nile virus (wnv) and st. louis encephalitis virus (slev) seroconversion events, which would indicate the current circulation of these viruses. overall, 331 (34.1%) of the 971 horses screened were positive for past infection with flaviviruses upon initial sampling in july 2006. during the 12-month study from july 2006-june 2007, 33 wnv seroconversions and 14 slev seroconversions were detected, most of which occur ...201122241119
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