RESUMO
Dengue viruses (DENV) cause 50-100 million cases of acute febrile disease every year, including 500,000 reported cases of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Viral factors have been proposed to influence the severity of the disease, but markers of virulence have never been identified on DENV. Three DENV serotype-1 isolates from the 2007 epidemic in Cambodia that are derived from patients experiencing the various clinical forms of dengue were characterized both phenotypically and genetically. Phenotypic characteristics in vitro, based on replication kinetics in different cell lines and apoptosis response, grouped isolates from DF and DHF patients together, whereas the virus isolate from a DSS patient showed unique features: a lower level of replication in mammalian cells and extensive apoptosis in mosquito cells. Genomic comparison of viruses revealed six unique amino acid residues in the membrane, envelope, and in non-structural genes in the virus isolated from the DSS patient.
Assuntos
Vírus da Dengue/isolamento & purificação , Vírus da Dengue/fisiologia , Dengue/virologia , Dengue Grave/virologia , Sequência de Aminoácidos , Animais , Camboja/epidemiologia , Linhagem Celular , Chlorocebus aethiops , Dengue/epidemiologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Surtos de Doenças , Genótipo , Humanos , Dados de Sequência Molecular , Fenótipo , Dengue Grave/epidemiologia , Células Vero , Replicação ViralRESUMO
The development and validation of a one-step, single-tube, real-time accelerated reverse-transcription loop-mediated isothermal amplification (RT-LAMP) for the detection of the L RNA segment of Rift Valley fever virus (RVFV) are described. The assay was performed at a constant temperature (63 degrees C), with a real-time follow-up using a LightCycler and a double-stranded-DNA-intercalating fluorochrome. The assay is highly sensitive and comparable to real-time RT-PCR, with a detection limit of approximately 10 RNA copies per assay. However, the RT-LAMP assay is much faster than traditional RT-PCR and generates results in <30 min for most diluted samples. The specificity of the primers was established using other, related arboviruses as well as virus-containing and virus-free sera. The RT-LAMP assay reported here is thus a valuable tool for the rapid detection of RVFV in field diagnostic laboratories.
Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Febre do Vale de Rift/diagnóstico , Vírus da Febre do Vale do Rift/isolamento & purificação , Primers do DNA/genética , Humanos , RNA Viral/genética , Febre do Vale de Rift/virologia , Sensibilidade e Especificidade , Fatores de TempoRESUMO
In 2015, the French Armed Forces deployed a biosafety level 3 (BSL3) field laboratory as a part of an Ebola treatment center in Guinea. When closing the center, laboratory decontamination operations were necessary. We present the decontamination protocols applied for the BSL3 field laboratory, making the entire module ready for a future use.
Assuntos
Descontaminação/métodos , Equipamentos Médicos Duráveis , Doença pelo Vírus Ebola/diagnóstico , Laboratórios , França , Guiné , Humanos , Instalações MilitaresRESUMO
Zika virus is an arthropod-borne Flavivirus member of the Spondweni serocomplex, transmitted by Aedes mosquitoes. We report here the complete coding sequence of a Zika virus strain belonging to the Asian lineage, isolated from an infected patient returning from French Polynesia, an epidemic area in 2013/2014.