Chikungunya Virus Net is the web resource for anyone interested in chikungunya. The objectives of Chikungunya Virus Net are to be the public and professional information resource for chikungunya and to serve as a network in the exchange of information and news related to chikungunya.

Chikungunya virus (CHIKV) is an insect-borne virus, of the genus Alphavirus, that is spread by Aedes mosquitoes. Chikungunya infection causes fever and severe joint pain. Other symptoms include muscle pain, headache, nausea, fatigue and rash. The disease shares some clinical signs with dengue, and can be misdiagnosed in areas where dengue is common. There have been recent breakouts of chikungunya in Africa, Asia and the Indian subcontinent. In recent decades mosquito vectors of chikungunya have spread to Europe and the Americas. In 2007, disease transmission was reported for the first time in Europe. There is no cure for the disease. Treatment is focused on relieving the symptoms.

• Vaccine for chikungunya virus is in development - News & Observer
  Fri, 25 Jul 2014 22:56:
• San Antonio confirms case of Chikungunya virus - KENS 5 TV
  Fri, 25 Jul 2014 21:55:
• Chikungunya virus confirmed in American Samoa - Radio New Zealand
  Fri, 25 Jul 2014 21:33:
• Chikungunya could be a future concern for NM - KOAT Albuquerque
  Fri, 25 Jul 2014 21:29:
• CDC Lab Moratorium Could Slow Work on Chikungunya Diagnoses - WABE 90.1 FM
  Fri, 25 Jul 2014 21:04:
• Suspected Case Of Chikungunya In Bermuda - Bernews
  Fri, 25 Jul 2014 20:46:
• 9 Must-Know Facts About The Chikungunya Virus - Huffington Post
  Fri, 25 Jul 2014 18:51:
• Delaware reports first case of mosquito borne chikungunya. - WDDE 91.1 FM | Delaware's NPR News station
  Fri, 25 Jul 2014 14:55:
• DCHHS reports first case of chikungunya - Star Local Media
  Fri, 25 Jul 2014 14:17:
• Summer tourists help spread chikungunya virus - Deutsche Welle
  Fri, 25 Jul 2014 12:11:

• A Novel MVA Vectored Chikungunya Virus Vaccine Elicits Protective Immunity in Mice.
  Weger-Lucarelli J, Chu H, Aliota MT, et al. A Novel MVA Vectored Chikungunya Virus Vaccine Elicits Protective Immunity in Mice. [JOURNAL ARTICLE]PLoS Negl Trop Dis 2014 Jul; 8(7):e2970.Chikungunya virus (CHIKV) is a re-emerging arbovirus associated with febrile illness often accompanied by rash and arthralgia that may persist for several years. Outbreaks are associated with high morbidity and create a public health challenge for countries affected. Recent outbreaks have occurred in both Europe and the Americas, suggesting CHIKV may continue to spread. Despite the sustained threat of the virus, there is no approved vaccine or antiviral therapy against CHIKV. Therefore, it is critical to develop a vaccine that is both well tolerated and highly protective.In this study, we describe the construction and characterization of a modified Vaccinia virus Ankara (MVA) virus expressing CHIKV E3 and E2 proteins (MVA-CHIK) that protected several mouse models from challenge with CHIKV. In particular, BALB/c mice were completely protected against viremia upon challenge with CHIKV after two doses of MVA-CHIK. Additionally, A129 mice (deficient in IFNα/β) were protected from viremia, footpad swelling, and mortality. While high anti-virus antibodies were elicited, low or undetectable levels of neutralizing antibodies were produced in both mouse models. However, passive transfer of MVA-CHIK immune serum to naïve mice did not protect against mortality, suggesting that antibodies may not be the main effectors of protection afforded by MVA-CHIK. Furthermore, depletion of CD4+, but not CD8+ T-cells from vaccinated mice resulted in 100% mortality, implicating the indispensable role of CD4+ T-cells in the protection afforded by MVA-CHIK.The results presented herein demonstrate the potential of MVA to effectively express CHIKV E3-E2 proteins and generate protective immune responses. Our findings challenge the assumption that only neutralizing antibodies are effective in providing protection against CHIKV, and provides a framework for the development of novel, more effective vaccine strategies to combat CHIKV.


• Characterization of Aedes aegypti Innate-Immune Pathways that Limit Chikungunya Virus Replication.
  McFarlane M, Arias-Goeta C, Martin E, et al. Characterization of Aedes aegypti Innate-Immune Pathways that Limit Chikungunya Virus Replication. [JOURNAL ARTICLE]PLoS Negl Trop Dis 2014 Jul; 8(7):e2994.Replication of arboviruses in their arthropod vectors is controlled by innate immune responses. The RNA sequence-specific break down mechanism, RNA interference (RNAi), has been shown to be an important innate antiviral response in mosquitoes. In addition, immune signaling pathways have been reported to mediate arbovirus infections in mosquitoes; namely the JAK/STAT, immune deficiency (IMD) and Toll pathways. Very little is known about these pathways in response to chikungunya virus (CHIKV) infection, a mosquito-borne alphavirus (Togaviridae) transmitted by aedine species to humans resulting in a febrile and arthralgic disease. In this study, the contribution of several innate immune responses to control CHIKV replication was investigated. In vitro experiments identified the RNAi pathway as a key antiviral pathway. CHIKV was shown to repress the activity of the Toll signaling pathway in vitro but neither JAK/STAT, IMD nor Toll pathways were found to mediate antiviral activities. In vivo data further confirmed our in vitro identification of the vital role of RNAi in antiviral defence. Taken together these results indicate a complex interaction between CHIKV replication and mosquito innate immune responses and demonstrate similarities as well as differences in the control of alphaviruses and other arboviruses by mosquito immune pathways.


• Bioactive Cembrane Derivatives from the Indian Ocean Soft Coral, Sinularia kavarattiensis.
  Lillsunde KE, Festa C, Adel H, et al. Bioactive Cembrane Derivatives from the Indian Ocean Soft Coral, Sinularia kavarattiensis. [Journal Article]Mar Drugs 2014; 12(7):4045-68.Marine organisms and their metabolites represent a unique source of potential pharmaceutical substances. In this study, we examined marine-derived substances for their bioactive properties in a cell-based Chikungunya virus (CHIKV) replicon model and for in vitro anti-inflammatory activity. In the screening of a marine sample library, crude extracts from the Indian soft coral, Sinularia kavarattiensis, showed promising activity against the CHIKV replicon. Bioassay-guided chemical fractionation of S. kavarattiensis resulted in the isolation of six known norcembranoids (1-6) and one new compound, named kavaranolide (7). The structures were elucidated on the basis of NMR and MS spectroscopic data. Compounds 1-3 and 5-7 were evaluated for their replicon-inhibiting potential in the CHIKV model by using a luminescence-based detection technique and live cell imaging. Compounds 1 and 2 showed moderate inhibition of the CHIKV replicon, but imaging studies also revealed cytotoxic properties. Moreover, the effects of the isolated compounds on primary microglial cells, an experimental model for neuroinflammation, were evaluated. Compound 2 was shown to modulate the immune response in microglial cells and to possess potential anti-inflammatory properties by dose-dependently reducing the release of pro- and anti-inflammatory cytokines.


• Critical role for BST-2 in acute Chikungunya virus infection.
  Mahauad-Fernandez WD, Jones PH, Okeoma CM Critical role for BST-2 in acute Chikungunya virus infection. [JOURNAL ARTICLE]J Gen Virol 2014 Jul 22.Bone marrow stromal antigen 2 (BST-2) also known as Tetherin) is an interferon-inducible gene that functions to block the release of a range of nascent enveloped virions from infected host cells. However, the role of BST-2 in viral pathogenesis remains poorly understood. BST-2 plays a multifaceted role in innate immunity-as it hinders retroviral infection and possibly promotes infection with some rhabdo and orthomyxo viruses. This paradoxical role has probably hindered exploration of BST-2 antiviral function in vivo. We previously reported that BST-2 tethers Chikungunya virus-like particle on the cell plasma membrane. To explore the role of BST-2 in Chikungunya virus (CHIKV) replication and host protection, we utilized Chikungunya virus strain 181/25 to examine early events during CHIKV infection in BST-2-/- mouse model. We observed interesting dichotomy between wild-type (WT) and BST-2-/- mice. BST-2 deficiency increased inoculation site viral load, culminating in higher systemic viremia and increased lymphoid tissues tropism. Suppressed inflammatory innate response demonstrated by impaired IFNα, IFNγ, and CD40 ligand (CD40L) expression was observed in BST-2-/- mice compared to the WT controls. These findings suggest that, in part, BST-2 protects lymphoid tissues from CHIKV infection and regulates CHIKV-induced inflammatory response by the host.


• Wolbachia Endosymbionts and Human Disease Control.
  Slatko BE, Luck AN, Dobson SL, et al. Wolbachia Endosymbionts and Human Disease Control. [JOURNAL ARTICLE]Mol Biochem Parasitol 2014 Jul 18.AbstractPublisher Full TextMost human filarial nematode parasites and arthropods are hosts for a bacterial endosymbiont, Wolbachia. In filaria, Wolbachia are required for normal development, fertility and survival, whereas in arthropods, they are largely parasitic and can influence development and reproduction, but are generally not required for host survival. Due to their obligate nature in filarial parasites, Wolbachia have been a target for drug discovery initiatives using several approaches including diversity and focused library screening and genomic sequence analysis. In vitro and in vivo anti-Wolbachia antibiotic treatments have been shown to have adulticidal activity, a long sought goal of filarial parasite drug discovery. In mosquitoes, it has been shown that the presence of Wolbachia can inhibit the transmission of certain viruses, such as Dengue, Chikungunya, Yellow Fever, West Nile, as well as the infectivity of the malaria-causing protozoan, Plasmodium and filarial nematodes. Furthermore, Wolbachia can cause a form of conditional sterility that can be used to suppress populations of mosquitoes and additional medically important insects. Thus Wolbachia, a pandemic endosymbiont offers great potential for elimination of a wide-variety of devastating human diseases.


• Role of skin immune cells on the host susceptibility to mosquito-borne viruses.
  Briant L, Desprès P, Choumet V, et al. Role of skin immune cells on the host susceptibility to mosquito-borne viruses. [REVIEW]Virology 2014 Jul 17.:26-32.AbstractPublisher Full TextDue to climate change and the propagation of competent arthropods worldwide, arboviruses have become pathogens of major medical importance. Early transmission to vertebrates is initiated by skin puncture and deposition of virus together with arthropod saliva in the epidermis and dermis. Saliva components have the capacity to modulate skin cell responses by enhancing and/or counteracting initial replication and establishment of systemic viral infection. Here, we review the nature of the cells targeted by arboviruses at the skin level and discuss the type of cellular responses elicited by these pathogens in light of the immunomodulatory properties of arthropod vector-derived salivary factors injected at the inoculation site. Understanding cutaneous arbovirus-host interactions may provide new clues for the design of future therapeutics.


• First case of locally acquired chikungunya is reported in US.
  McCarthy M First case of locally acquired chikungunya is reported in US. [Journal Article]BMJ 2014.:g4706.Publisher Full Text


• Neurocognitive Outcome of Children Exposed to Perinatal Mother-to-Child Chikungunya Virus Infection: The CHIMERE Cohort Study on Reunion Island.
  Gérardin P, Sampériz S, Ramful D, et al. Neurocognitive Outcome of Children Exposed to Perinatal Mother-to-Child Chikungunya Virus Infection: The CHIMERE Cohort Study on Reunion Island. [Journal Article]PLoS Negl Trop Dis 2014 Jul; 8(7):e2996.AbstractPMC Free Full TextPublisher Full TextLittle is known about the neurocognitive outcome in children exposed to perinatal mother-to-child Chikungunya virus (p-CHIKV) infection.The CHIMERE ambispective cohort study compared the neurocognitive function of 33 p-CHIKV-infected children (all but one enrolled retrospectively) at around two years of age with 135 uninfected peers (all enrolled prospectively). Psychomotor development was assessed using the revised Brunet-Lezine scale, examiners blinded to infectious status. Development quotients (DQ) with subscores covering movement/posture, coordination, language, sociability skills were calculated. Predictors of global neurodevelopmental delay (GND, DQ≤85), were investigated using multivariate Poisson regression modeling. Neuroradiologic follow-up using magnetic resonance imaging (MRI) scans was proposed for most of the children with severe forms.The mean DQ score was 86.3 (95%CI: 81.0-91.5) in infected children compared to 100.2 (95%CI: 98.0-102.5) in uninfected peers (P<0.001). Fifty-one percent (n = 17) of infected children had a GND compared to 15% (n = 21) of uninfected children (P<0.001). Specific neurocognitive delays in p-CHIKV-infected children were as follows: coordination and language (57%), sociability (36%), movement/posture (27%). After adjustment for maternal social situation, small for gestational age, and head circumference, p-CHIKV infection was found associated with GND (incidence rate ratio: 2.79, 95%CI: 1.45-5.34). Further adjustments on gestational age or breastfeeding did not change the independent effect of CHIKV infection on neurocognitive outcome. The mean DQ of p-CHIKV-infected children was lower in severe encephalopathic children than in non-severe children (77.6 versus 91.2, P<0.001). Of the 12 cases of CHIKV neonatal encephalopathy, five developed a microcephaly (head circumference <-2 standard deviations) and four matched the definition of cerebral palsy. MRI scans showed severe restrictions of white matter areas, predominant in the frontal lobes in these children.The neurocognitive outcome of children exposed to perinatal mother-to-child CHIKV infection is poor. Severe CHIKV neonatal encephalopathy is associated with an even poorer outcome.


• Chikungunya Virus: A Major Emerging Threat.
  Higgs S Chikungunya Virus: A Major Emerging Threat. [JOURNAL ARTICLE]Vector Borne Zoonotic Dis 2014 Jul 16.Publisher Full TextPublisher Full Text


• Chikungunya at the Door - Déjà Vu All Over Again?
  Morens DM, Fauci AS Chikungunya at the Door - Déjà Vu All Over Again? [JOURNAL ARTICLE]N Engl J Med 2014 Jul 16.AbstractPublisher Full TextPublisher Full TextIn 2008, we noted that the global reemergence of dengue fever threatened U.S. residents.(1) An outbreak of locally acquired dengue subsequently occurred in Florida, and the risk of U.S. dengue outbreaks will probably continue indefinitely. We now face a new threat posed by the unrelated chikungunya virus, which causes a disease clinically similar to dengue in a similar epidemiologic pattern, which is transmitted by the same mosquito vectors, and for which we also lack vaccines and specific treatments. In December 2013, an outbreak of chikungunya fever appeared in the French sector of Saint-Martin/Sint Maarten and spread epidemically throughout the French . . .