Chikungunya virus (CHIKV) is an emerging arbovirus associated with several recent large-scale epidemics. The 2005-2006 epidemic on Reunion island that resulted in approximately 266,000 human cases was a strain of CHIKV mutation the envelope protein gene (E1-A226V). To test hypothesis this (strain LR2006 OPY1) might influence fitness for different vector species, viral infectivity, dissemination, and transmission were compared Aedes albopictus, species implicated epidemic, recognized Ae....

Chikungunya virus (CHIKV), a mosquito-borne alphavirus, has traditionally circulated in Africa and Asia, causing human febrile illness accompanied by severe, chronic joint pain. In Africa, epidemic emergence of CHIKV involves the transition from an enzootic, sylvatic cycle involving arboreal mosquito vectors nonhuman primates, into urban where peridomestic mosquitoes transmit among humans. however, appears to circulate only endemic, cycle. Recently, emerged Indian Ocean subcontinent cause...

The adaptation of Chikungunya virus (CHIKV) to a new vector, the Aedes albopictus mosquito, is major factor contributing its ongoing re-emergence in series large-scale epidemics arthritic disease many parts world since 2004. Although initial step CHIKV A. was determined involve an A226V amino acid substitution E1 envelope glycoprotein that first arose 2005, little attention has been paid subsequent evolution after this adaptive mutation convergently selected several geographic locations. To...

Adaptation of RNA viruses to a new host or vector species often results in emergence viral lineages. However, lineage-specific restrictions on the adaptive processes remain largely unexplored. Recently, Chikungunya virus (CHIKV) lineage African origin emerged cause major epidemics severe, persistent, debilitating arthralgia Africa and Asia. Surprisingly, this is actively replacing endemic strains Southeast Asia that have been circulating there for 60 y. This replacement process associated...

Between 2005 and 2007 Chikungunya virus (CHIKV) caused its largest outbreak/epidemic in documented history. An unusual feature of this epidemic is the involvement Ae. albopictus as a principal vector. Previously we have demonstrated that single mutation E1-A226V significantly changed ability to infect be transmitted by vector when expressed background well characterized CHIKV strains LR2006 OPY1 37997. However, current study demonstrate introduction into an infectious clone derived from...

The recent outbreak of Chikungunya virus (CHIKV) on several islands in the Indian Ocean and India has focused attention this reemerging highlighted need for development new tools to study vector-virus-host interactions. We have constructed characterized, cell culture, Aedes aegypti Ae. albopictus mosquitoes, infectious cDNA clones CHIKV using a isolate from La Réunion Island. Comparison growth kinetics infection rates viral strain LR2006 OPY1 (CHIKV-LR) full-length clone (CHIKV-LR ic)...

Chikungunya virus (CHIKV) is a reemerging mosquito-borne pathogen that has recently caused devastating urban epidemics of severe and sometimes chronic arthralgia. As with most other viral diseases, control relies on reducing mosquito populations their contact people, which been ineffective in locations. Therefore, vaccines remain the best strategy to prevent vector-borne diseases. Ideally, for diseases resource-limited countries should combine low cost single dose efficacy, yet induce rapid...

An arthropod-borne virus, Zika virus (ZIKV), has recently emerged as a major human pathogen. Associated with complications during perinatal development and Guillain-Barré syndrome in adults, ZIKV raises new challenges for understanding the molecular determinants of flavivirus pathogenesis. This underscores necessity reverse genetic system based on an epidemic strain. Here, we describe generation characterization cell cultures infectious cDNA clone isolated from 2015 Brazil. The cDNA-derived...

The 3′ untranslated genome region (UTR) of arthropod-borne viruses is characterized by enriched direct repeats (DRs) and stem-loop structures. Despite many years theoretical experimental study, on-going positive selection on the 3′UTR had never been observed in 'real-time,' role arbovirus remains poorly understood. We a lineage-specific sequence pattern all available Asian lineage mosquito-borne alphavirus, chikungunya virus (CHIKV) (1958–2009), including complicated mutation duplication...

O'nyong-nyong virus (ONNV) and chikungunya (CHIKV) are closely related alphaviruses that cause human disease in Africa Asia. Like most alphaviruses, CHIKV is vectored by culicine mosquitoes. ONNV considered unusual as it primarily infects anopheline mosquitoes; however, there relatively few experimental data to support this. In this study, three strains of one strain were evaluated Anopheles gambiae Aedes aegypti mosquitoes four cell lines. As predicted, was not infectious An. gambiae, we...

Mayaro virus (MAYV) is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine available for MAYV infection, we capitalized on IRES-based approach develop live-attenuated candidate. Testing infant, immunocompetent as well interferon receptor-deficient mice demonstrated high degree attenuation, strong induction neutralizing antibodies, efficacy against lethal...

Abstract Background Phylogenetic and functional analysis was conducted on an Anopheles gambiae gene, ENSANGG00000017398. Based phylogenetic analysis, this gene belongs to the same lineage as Heat shock protein cognate 70-4 (Hsc70-4) in Drosophila . Accordingly, we propose name 70B (HSC70B). We previously reported that expression of HSC70B other genes including elongation factor-1α (EF-1α) agglutinin attachment subunit (agglutinin) were up-regulated o'nyong-nyong virus (ONNV)-infected female...

Chikungunya virus (CHIKV) is a mosquito transmitted alphavirus that recently caused several large scale outbreaks/epidemics of arthritic disease in tropics Africa, Indian Ocean basin and South-East Asia. This re-emergence event was facilitated by genetic adaptation (E1-A226V substitution) CHIKV to newly significant vector for this virus; Aedes albopictus. However, the molecular mechanism explaining positive effect E1-A226V mutation on fitness remains largely unknown. Previously we...

The Zika virus (ZIKV) was first isolated in Africa 1947. It shown to be a mild that had limited threat humans. However, the resurgence of ZIKV most recent Brazil outbreak surprised us because it causes severe human congenital and neurologic disorders including microcephaly newborns Guillain-Barré syndrome adults. Studies showed epidemic strains are phenotypically different from historic strains, suggesting has acquired mutations associated with altered viral pathogenicity. what genetic...

Sexual transmission and persistence of Zika virus (ZIKV) in the male reproductive tract (MRT) poses new challenges for controlling outbreaks developing live-attenuated vaccines. To elucidate routes ZIKV dissemination MRT, we here generate microRNA-targeted clones that lose infectivity (1) cells inside seminiferous tubules testis, or (2) epithelial epididymis. We trace MRT using an established mouse model pathogenesis. Our results support a which infects testis via hematogenous route, while...

Live-attenuated virus vaccines are key components in controlling arboviral diseases, but they must not disseminate or be transmitted by mosquito vectors. Although the cycles which many mosquito-borne viruses well understood, role of viral genetics these processes has been fully elucidated. Yellow fever (YFV) is an important arbovirus and prototype member family Flaviviridae. Here, YFV was used Aedes aegypti mosquitoes as a model to investigate genetic basis infection dissemination...

Candidate vaccine ChimeriVax viruses are attenuated, efficacious, safe, and highly unlikely to be transmitted by arthropod vectors. Nevertheless, concerns have been raised about the use of these vaccines because potential for recombination between wild-type (WT) strains. To evaluate vertebrate pathogenicity such a worst-case recombinant, ChimeriVax-dengue (DEN) 4 virus was chimerized with WT Asibi yellow fever virus. In this scenario, chimeric remained fully attenuated in nonhuman primates....

We report the construction and comparative characterization of a full-length West Nile virus (WNV) cDNA infectious clone (ic) that contains green fluorescent protein (GFP) expression cassette fused within viral open reading frame. Virus derived from WNV-GFP ic stably infected Culex pipiens quinquefasciatus mosquitoes at comparable rates to parental (non-GFP) ic. However, insertion this GFP resulted in temporal delay vivo replication kinetics significantly decreased dissemination head tissue....

Ixodes scapularis ticks transmit many infectious agents that cause disease, including tick-borne flaviviruses (TBFVs). TBFV infections thousands of human encephalitis cases worldwide annually. In the United States, with Powassan virus (POWV) are increasing and have a fatality rate 10 to 30%. Additionally, Langat (LGTV) is low neurovirulence used as model TBFV. replication dissemination within I. organs poorly characterized, deeper understanding biology in this vector may inform effective...

Sexual transmission and persistence of Zika virus (ZIKV) in the testes pose new challenges for controlling outbreaks developing live-attenuated vaccines. It has been shown that testicular infection ZIKV is initiated interstitium, followed by spread seminiferous tubules. This leads to damage and/or viral dissemination into epididymis eventually semen. However, it remains unknown which cell types are targeted what specific order infectious events leading invasion Here, we demonstrate...