Alphavirus Infections ; diagnosis ; epidemiology ; virology ; Animals ; Chikungunya Fever ; Chikungunya virus ; genetics ; isolation & purification ; physiology ; Humans ; Viral Proteins ; genetics ; metabolism

This report describes the chikungunya cases and local transmission detected in Brunei Darussalam for the first time, despite the country being situated in a region that has experienced a multitude of outbreaks over the years. A combined strategy of active case detection, patient isolation and vector control measures was deployed in an attempt to avert further transmission. The findings have important public health implications for international surveillance and control strategies for this re-emerging disease.
Adult ; Alphavirus Infections ; diagnosis ; epidemiology ; transmission ; Brunei ; epidemiology ; Chikungunya Fever ; Disease Outbreaks ; prevention & control ; Female ; Humans ; Male ; Middle Aged ; Population Surveillance

PURPOSE: Chikungunya virus (CHIKV) causes endemic or epidemic outbreaks of CHIKV fever, which is a mosquitoe-transmitted viral disease in Africa, India, South-East Asia, and recently Southern Europe. Currently, serological diagnostic tests such as hemagglutination inhibition test (HI test), in-house IgM capture enzyme-linked immunosorbent assays (ELISA), and indirect immunofluorescence test were used for diagnosis of chikungunya fever, which are based on whole virus antigens. MATERIALS AND METHODS: CHIKV E1, and E2 envelope proteins for the CHIKV-specific serodiagnostic reagents for chikungunya fever were expressed in baculovirus expression system. The seroreactivity of recombinant CHIKV E1 and E2 envelope proteins were evaluated using sera panels of patients from Laboratoire Marcel Merieux by indirect IgM capture ELISA. RESULTS: The recombinant CHIKV E1 and E2 envelope protein showed sensitivity of 77.5% and 90%, respectively. The specificities of both CHIKV E1 and E2 envelope proteins were 100%. CONCLUSION: The recombinant CHIKV E1 and E2 envelope proteins could be a useful diagnostic reagent for CHIKV infection.
Alphavirus Infections/*diagnosis ; Animals ; Baculoviridae/genetics/metabolism ; Cells, Cultured ; Chikungunya virus/genetics ; Cloning, Molecular ; Enzyme-Linked Immunosorbent Assay/methods ; Recombinant Proteins/immunology ; Sensitivity and Specificity ; Serologic Tests/*methods ; Viral Envelope Proteins/*immunology

BACKGROUNDTo develop a rapid, specific and sensitive method for detecting Sindbis virus (SINV) with SYBR GREEN I real time PCR.

METHODSTotal RNA of strains of Sindbis virus and a related virus were extracted and reverse transcribed to cDNAs. With the cDNAs as template, the SYBR GREEN I real time PCR assay was developed and optimized on ABI 7300 apparatus for specific-detection of Sindbis virus, and the sensitivity, specificity and reproducibility were evaluated.

RESULTSFor the PCR, 55 degrees C was chosen as the optimal anneal temperature and 0.5 micromol/L as the optimal primer concentration. Using this method, all the selected SINV were detected as positive, while the results of control arboviruses such as Geta virus, Japanese encephalitis virus (JEV), Batai virus, Seadornavirus Orbiviruses and synthesized WEEV cDNA were negative. With this system, 0.1 PFU/ml SINV cDNA could be detected; The sensitivity of this assay was about 100 times higher than standard RT-PCR. All the results were reproducible within two compatible tests, and the stability of the detection system was very good. The test results of simulated infection human serum samples showed that human serum had no obvious interference with this system. With this system, 6 of 151 clinical samples with unknown fever or encephalitis were determined as positive.

CONCLUSIONThe developed SYBR GREEN I real time PCR assay for detecting Sindbis virus was highly sensitive, specific and showed a good reproducibility and stability. It is our belief that the present method can be further used in clinic sample to verify its stringency.

Alphavirus Infections ; diagnosis ; virology ; DNA, Complementary ; chemistry ; genetics ; Organic Chemicals ; chemistry ; RNA, Viral ; genetics ; isolation & purification ; Reproducibility of Results ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Sensitivity and Specificity ; Sindbis Virus ; genetics