Welcome to Chikungunya Virus Net
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.
Chikungunya News and Headlines
- WHO sees first chikungunya cases in western hemisphere - AFP
Tue, 10 Dec 2013 19:05:
- Chikungunya makes first appearance in the Caribbean, St. Martins confirms two ... - The Global Dispatch
Tue, 10 Dec 2013 13:01:
- Is the mosquito-borne Chikungunya virus taking root in Singapore? - Straits Times
Wed, 04 Dec 2013 08:37:
- Gujarat sees multifold rise in cases of dengue, chikungunya - Indian Express
Wed, 04 Dec 2013 01:57:
- DOH: 'Chikungunya' cases soar past 1000, doubled from last year - InterAksyon
Tue, 03 Dec 2013 20:56:
- Chikungunya fever cases top 1600 in the Philippines, nearly triple 2012 numbers - The Global Dispatch
Tue, 03 Dec 2013 17:52:
- Chikungunya outbreak reported on the island of Yap - The Global Dispatch
Sun, 24 Nov 2013 14:18:
- Chikungunya cases on rise in Ahmedabad - Times of India
Tue, 19 Nov 2013 09:07:
- Blood test confirms 'Chikungunya' in Dhaka - DhakaTribune
Sun, 17 Nov 2013 04:18:
- Chikungunya Virus Not Yet Reported on Guam but DPHSS Says It Could Easily ... - Pacific News Center
Thu, 14 Nov 2013 08:25:
Latest Articles on Chikungunya
- Chikungunya as a cause of acute febrile illness in southern sri lanka.
Reller ME, Akoroda U, Nagahawatte A, et al. Chikungunya as a cause of acute febrile illness in southern sri lanka. [Journal Article]PLoS One 2013; 8(12):e82259.AbstractPMC Free Full TextPublisher Full TextChikungunya virus (CHIKV) re-emerged in Sri Lanka in late 2006 after a 40-year hiatus. We sought to identify and characterize acute chikungunya infection (CHIK) in patients presenting with acute undifferentiated febrile illness in unstudied rural and semi-urban southern Sri Lanka in 2007.We enrolled febrile patients ≥ 2 years of age, collected uniform epidemiologic and clinical data, and obtained serum samples for serology, virus isolation, and real-time reverse-transcriptase PCR (RT-PCR). Serology on paired acute and convalescent samples identified acute chikungunya infection in 3.5% (28/797) patients without acute dengue virus (DENV) infection, 64.3% (18/28) of which were confirmed by viral isolation and/or real-time RT-PCR. No CHIKV/DENV co-infections were detected among 54 patients with confirmed acute DENV. Sequencing of the E1 coding region of six temporally distinct CHIKV isolates (April through October 2007) showed that all isolates posessed the E1-226A residue and were most closely related to Sri Lankan and Indian isolates from the same time period. Except for more frequent and persistent musculoskeletal symptoms, acute chikungunya infections mimicked DENV and other acute febrile illnesses. Only 12/797 (1.5%) patients had serological evidence of past chikungunya infection.Our findings suggest CHIKV is a prominent cause of non-specific acute febrile illness in southern Sri Lanka.
- Stable, high-level expression of reporter proteins from improved alphavirus expression vectors to track replication and dissemination during encephalitic and arthritogenic disease.
Sun C, Gardner CL, Watson AD, et al. Stable, high-level expression of reporter proteins from improved alphavirus expression vectors to track replication and dissemination during encephalitic and arthritogenic disease. [JOURNAL ARTICLE]J Virol 2013 Dec 4.AbstractPublisher Full TextEngineered alphavirus vectors expressing reporters of infection have been used for a number of years due to their relatively low costs for analysis of virus replication and the capacity to utilize imaging systems for longitudinal measurements of growth within single animals. In general, these vectors have been derived from "Old World" alphaviruses using a second viral subgenomic promoter to express the transgenes, placed either immediately after the nonstructural proteins or at the 3' end of the viral coding sequences. However, the relevance of these vectors to natural infections is questionable as they have not been rigorously tested for virulence in vivo in comparison with parental viruses or for the retention of the reporter during replication. Here, we report construction of new expression vectors for two Old World arthritogenic alphaviruses (Sindbis and chikungunya viruses) and two New World encephalitic alphaviruses (eastern and Venezuelan equine encephalitis viruses) based upon either fusion of the reporter protein in-frame within non-structural protein 3 or insertion of the reporter as a cleavable element between the capsid and PE2 structural proteins. We have compared these with a traditional 3' double subgenomic promoter virus expressing either a large, firefly luciferase, (fLuc, 1,650 nucleotide) or small, NanoLuc (nLuc, 513 nucleotide), luminescent reporter protein. Results indicate that the nLuc is substantially more stable than fLuc during repeated rounds of infection regardless of the transgene location. However, the capsid-PE2 insertion and nsP3-fusion viruses exhibit the most authentic mimicking of parental virus infection regardless of expressed protein.
- Aedes albopictus (Skuse) males in laboratory and semi-field cages: Release ratios and mating competitiveness.
Madakacherry O, Lees RS, Gilles JR Aedes albopictus (Skuse) males in laboratory and semi-field cages: Release ratios and mating competitiveness. [JOURNAL ARTICLE]Acta Trop 2013 Dec 1.AbstractPublisher Full TextTo control the container-breeding mosquito and major vector of dengue and chikungunya Aedes albopictus, the sterile insect technique (SIT) is proposed as a component of integrated vector management programs in endemic areas. For the technique to be successful, released males, sterilized with 35Gy of ionizing radiation during the pupal stage, must be able to compete for mating opportunities with wild counterparts and successfully copulate with wild females to induce sterility in the population. Any reduction in competitiveness can be compensated for by increasing the ratio of released sterile to wild males, a ratio which must be optimized for effectiveness and efficiency. Fruit fly SIT programs use field enclosures to test the competitiveness of sterile males to monitor the quality of the colony and adjust release ratios. This is laborious and time consuming, and for mosquito programs it would be advantageous if similarly useful results could be obtained by smaller scale laboratory tests, conducted on a more regular basis. In the present study we compared the competitiveness, as measured by hatching rate of resulting egg batches, of irradiated males measured in small and large laboratory cages and semi-field enclosures in a greenhouse setting, when competing in a 1:1, 3:1, and 5:1 ratio with fertile males. The sterile males were found to be equally competitive when compared to unirradiated counterparts, and a 5:1 ratio was sufficient to reduce, but not eliminate, the fertility of the female populations, irrespective of cage size. Variability in hatch rate in eggs laid by individual females and so-called indeterminate matings, when we could not be certain whether a female had mated a fertile or a sterile male, could be investigated by closer investigation of mating status and the frequency of multiple matings in Ae. albopictus. The laboratory results are encouraging for the effectiveness of the SIT using irradiated males of this species, and we support further assessment in the field.
- Serological correlates of immune protection conferred by Chikungunya virus infection.
Sheela PJ, Sumathy K Serological correlates of immune protection conferred by Chikungunya virus infection. [Journal Article]Acta Virol 2013; 57(4):471-3.AbstractPublisher Full TextChikungunya virus (CHIKV), an Alphavirus of the family Togaviridae is a positive strand RNA virus that is transmitted commonly by the Aedes mosquitoes. The characteristic clinical symptom of the virus infection is incapacitating arthralgia that could persist for few weeks to several months in the affected individuals (1, 2). High morbidity with severe polyarthralgia, rashes and ocular, hemorrhagic and sensorineural complications are reported in the re-emerging infection (3-5). The acquisition of an A226V mutation in the envelope protein E1 has increased the transmissibility of the virus in the widely prevalent Ae. Albopictus mosquitoes (6). CHIKV infection has become more widespread in the recent years as the mosquito vectors have expanded into new areas. Imported cases of CHIKV have been reported in nearly 40 countries until now (7). Keywords: chikungunya virus; antibody, serum neutralization test; 50% plaque reduction neutralization test; hemagglutination-inhibition test.
- Guidelines to site selection for population surveillance and mosquito control trials: A case study from Mauritius.
Iyaloo DP, Elahee KB, Bheecarry A, et al. Guidelines to site selection for population surveillance and mosquito control trials: A case study from Mauritius. [JOURNAL ARTICLE]Acta Trop 2013 Nov 23.AbstractPublisher Full TextMany novel approaches to controlling mosquito vectors through the release of sterile and mass reared males are being developed in the face of increasing insecticide resistance and other limitations of current methods. Before full scale release programmes can be undertaken there is a need for surveillance of the target population, and investigation of parameters such as dispersal and longevity of released, as compared to wild males through mark-release-recapture (MRR) and other experiments, before small scale pilot trials can be conducted. The nature of the sites used for this field work is crucial to ensure that a trial can feasibly collect sufficient and relevant information, given the available resources and practical limitations, and having secured the correct regulatory, community and ethical approvals and support. Mauritius is considering the inclusion of the sterile insect technique (SIT), for population reduction of Aedes albopictus, as a component of the Ministry of Health and Quality of Life's 'Operational Plan for Prevention and Control of Chikungunya and Dengue'. As part of an investigation into the feasibility of integrating the SIT into the Integrated Vector Management (IVM) scheme in Mauritius a pilot trial is planned. Two potential sites have been selected for this purpose, Pointe des Lascars and Panchvati, villages in the North East of the country, and population surveillance has commenced. This case study will here be used to explore the considerations which go into determining the most appropriate sites for mosquito field research. Although each situation is unique, and an ideal site may not be available, this discussion aims to help researchers to consider and balance the important factors and select field sites that will meet their needs.
- Combined miRNA and mRNA Signature Identifies Key Molecular Players and Pathways Involved in Chikungunya Virus Infection in Human Cells.
Saxena T, Tandon B, Sharma S, et al. Combined miRNA and mRNA Signature Identifies Key Molecular Players and Pathways Involved in Chikungunya Virus Infection in Human Cells. [Journal Article]PLoS One 2013; 8(11):e79886.AbstractPMC Free Full TextPublisher Full TextSince its discovery, Chikungunya fever caused by a virus (CHIKV) has ravaged most of Africa and Southeast Asia. Despite there being more than a million reported cases in India alone and the seriousness of the disease in the chronic phase, a clear understanding of the disease pathogenesis and host response remains elusive. Here, we use microarray technology and quantitative PCR method to establish the complete miRNA, snoRNA and mRNA signature of host response upon CHIKV infection in human cell line infection model, HEK293T. The results were further validated in human primary cells (dermal fibroblasts). miRNA expression profiling revealed regulation of 152 miRNAs post CHIKV infection. An interesting overlap in miRNA signature was seen majorly with HCV, HPV and HIV1 virus. The microarray data further validated by qRT-PCR revealed induction of miR-744, miR-638, miR-503 and others among the top upregulated miRNAs. Notably, we found induction of snoRNAs belonging to C/D cluster including close paralogs of U3, U44, U76 and U78 snoRNAs. Genes were found to be differentially expressed along 3 major pathways; TGF-β, endocytosis and the cell cycle pathways. qRT-PCR data confirmed strong induction of TGF-β (SMAD6, JUN, SKIL) and endocytosis pathway (CXCR4, HSPA8, ADRB1) genes while downregulation of cell cycle genes (CDC27 and CDC23). Interestingly, use of TGF-β inhibitor, SB-431542, increased CHIKV mediated cell death. Overall, this study aims at providing the first complete transcriptome signature of host response upon CHIKV infection to aid identification of possible biomarkers and therapeutic targets.
- Vector population manipulation for control of arboviruses - a novel prospect for India.
Niranjan Reddy B, Gupta B, Rao BP Vector population manipulation for control of arboviruses - a novel prospect for India. [JOURNAL ARTICLE]Pest Manag Sci 2013 Oct 31.AbstractPublisher Full TextIndia, the seventh largest country in the world, has diverse geographical and climatic regions with vast rural and peri-urban areas. Many are experiencing an escalation in the spread and intensity of numerous human diseases transmitted by insects. Classically, the management of these vector-borne diseases is underpinned by either chemical insecticides and/or environmental management targeted at the vector. However, these methods or their present implementation do not offer acceptable levels of control, and more effective and sustainable options are now available. Genetic strategies for the prevention of arbovirus transmission are most advanced for dengue and chikungunya, targeting their primary vector, Aedes aegypti. The national burden in terms of morbidity and mortality as a direct consequence of dengue virus in India is considered to be the largest worldwide, over 4 times that of any other country. Presently, new genetic technologies are undergoing field evaluation of their biosafety and efficacy in several countries. This paper discusses the merits of these approaches and argues for fair and transparent appraisal in India as a matter of urgency. Identification of any associated risks and their appropriate mitigation are fundamental to that process. © 2013 Society of Chemical Industry.
- Harnessing mosquito-Wolbachia symbiosis for vector and disease control.
Bourtzis K, Dobson SL, Xi Z, et al. Harnessing mosquito-Wolbachia symbiosis for vector and disease control. [JOURNAL ARTICLE]Acta Trop 2013 Nov 16.AbstractPublisher Full TextMosquito species, members of the genera Aedes, Anopheles and Culex, are the major vectors of human pathogens including protozoa (Plasmodium sp.), filariae and of a variety of viruses (causing dengue, chikungunya, yellow fever, West Nile). There is lack of efficient methods and tools to treat many of the diseases caused by these major human pathogens, since no efficient vaccines or drugs are available; even in malaria where insecticide use and drug therapies have reduced incidence, 219 million cases still occurred in 2010. Therefore efforts are currently focused on the control of vector populations. Insecticides alone are insufficient to control mosquito populations since reduced susceptibility and even resistance is being observed more and more frequently. There is also increased concern about the toxic effects of insecticides on non-target (even beneficial) insect populations, on humans and the environment. During recent years, the role of symbionts in the biology, ecology and evolution of insect species has been well-documented and has led to suggestions that they could potentially be used as tools to control pests and therefore diseases. Wolbachia is perhaps the most renowned insect symbiont, mainly due to its ability to manipulate insect reproduction and to interfere with major human pathogens thus providing new avenues for pest control. We herein present recent achievements in the field of mosquito-Wolbachia symbiosis with an emphasis on Aedes albopictus. We also discuss how Wolbachia symbiosis can be harnessed for vector control as well as the potential to combine the sterile insect technique and Wolbachia-based approaches for the enhancement of population suppression programs.
- Neutralizing monoclonal antibodies to the E2 protein of chikungunya virus protects against disease in a mouse model.
Goh LY, Hobson-Peters J, Prow NA, et al. Neutralizing monoclonal antibodies to the E2 protein of chikungunya virus protects against disease in a mouse model. [Journal Article]Clin Immunol 2013 Dec; 149(3):487-97.AbstractPublisher Full TextChikungunya virus (CHIKV) recently caused the largest epidemic ever recorded for this virus involving an estimated 1.4-6.5million cases, with imported cased reported in over 40 countries. The number of monoclonal antibodies specific for this re-emerging alphavirus is currently limited. Herein we describe the generation and characterisation of five monoclonal antibodies specific for the E2 glycoprotein of CHIKV. The antibodies detected a range of CHIKV isolates in several assays including ELISA, Western blot, immunofluorescence assay (IFA) and immunohistochemistry (IHC) without evidence of cross-reactivity with other alphaviruses. Four antibodies also neutralised CHIKV in vitro, two of which provided complete protection against arthritis in a CHIKV mouse model when administered prior to infection. Given the current shortage of widely available reagents for CHIKV, these specific antibodies will be useful not only in research, but may also provide the basis for new diagnostics and treatments.
- Neutrophils: neglected players in viral diseases.
Gabriel C, Her Z, Ng LF Neutrophils: neglected players in viral diseases. [Journal Article]DNA Cell Biol 2013 Dec; 32(12):665-75.AbstractPublisher Full TextPublisher Full TextIncreasing evidence has shown that neutrophils are able to crosstalk with various immune cells and have paradoxical roles in pathogen infections. However, the role of neutrophils in viral infections remains poorly defined. Here, the various roles that neutrophils play in viral infections and in host immunity are discussed. Various activation mechanisms of neutrophils following virus interactions and the consequences that affect disease pathogenesis are also addressed. Such knowledge not only could be used in the development of tools for clinical management but would also value-add to the current understanding of innate immunity in viral infections and disease pathogenesis.