Chikungunya virus, Cameroon, 2006 Peyrefitte, Christophe N; Rousset, Dominique; Pastorino, Boris A M ...
Emerging infectious diseases,
05/2007, Letnik:
13, Številka:
5
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We report the isolation of chikungunya virus from a patient during an outbreak of a denguelike syndrome in Cameroon in 2006. The virus was phylogenetically grouped in the Democratic Republic of the ...Congo cluster, indicating a continuous circulation of a genetically similar chikungunya virus population during 6 years in Central Africa.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The threat of bioterrorism Tournier, Jean-Nicolas; Peyrefitte, Christophe N; Biot, Fabrice ...
Lancet. Infectious diseases/The Lancet. Infectious diseases,
January 2019, 2019-01-00, 20190101, 2019-01, Letnik:
19, Številka:
1
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The case-fatality rate of a provoked infectious event has both social and economic impacts. ...the economic cost might be much higher than the number of human casualties, as was observed in 2001, in ...the anthrax letter attacks (five deaths vs millions of US dollars in the decontamination process expenses).5 The European Centre for Disease Prevention and Control reviewed the disease prioritisation methodology in 2015,6 in a report examining the best practices for ranking infectious disease threats. The bioterrorist threat assessment should be regularly re-assessed, because threats can evolve swiftly with viral disease eradications and emergence of new pathogens, including those related to synthetic biology. ...our modern societies are now much more sensitive to unexpected events, with a high media exposure, reflecting the emerging role of social networks. ...although probably provoking a severe health and societal crisis, bioterrorism is a variation of the natural emergence of infectious diseases.
Since the official declaration of smallpox eradication in 1980, the general population vaccination has ceased worldwide. Therefore, people under 40 year old are generally not vaccinated against ...smallpox and have no cross protection against orthopoxvirus infections. This naïve population may be exposed to natural or intentional orthopoxvirus emergences. The virology unit of the Institut de Recherche Biomédicale des Armées (France) has developed research programs on orthopoxviruses since 2000. Its missions were conceived to improve the diagnosis capabilities, to foster vaccine development, and to develop antivirals targeting specific viral proteins. The role of the virology unit was asserted in 2012 when the responsibility of the National Reference Center for the Orthopoxviruses was given to the unit. This article presents the evolution of the unit activity since 2000, and the past and current research focusing on orthopoxviruses.
West Nile virus in Morocco, 2003 Schuffenecker, Isabelle; Peyrefitte, Christophe N; el Harrak, Mohammed ...
Emerging infectious diseases,
02/2005, Letnik:
11, Številka:
2
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West Nile virus (WNV) reemerged in Morocco in September 2003, causing an equine outbreak. A WNV strain isolated from a brain biopsy was completely sequenced. On the basis of phylogenetic analyses, ...Moroccan WNV strains isolated during the 1996 and 2003 outbreaks were closely related to other strains responsible for equine outbreaks in the western Mediterranean basin.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Vaccinia virus polymerase holoenzyme is composed of the DNA polymerase catalytic subunit E9 associated with its heterodimeric co-factor A20·D4 required for processive genome synthesis. Although A20 ...has no known enzymatic activity, D4 is an active uracil-DNA glycosylase (UNG). The presence of a repair enzyme as a component of the viral replication machinery suggests that, for poxviruses, DNA synthesis and base excision repair is coupled. We present the 2.7 Å crystal structure of the complex formed by D4 and the first 50 amino acids of A20 (D4·A201–50) bound to a 10-mer DNA duplex containing an abasic site resulting from the cleavage of a uracil base. Comparison of the viral complex with its human counterpart revealed major divergences in the contacts between protein and DNA and in the enzyme orientation on the DNA. However, the conformation of the dsDNA within both structures is very similar, suggesting a dominant role of the DNA conformation for UNG function. In contrast to human UNG, D4 appears rigid, and we do not observe a conformational change upon DNA binding. We also studied the interaction of D4·A201–50 with different DNA oligomers by surface plasmon resonance. D4 binds weakly to nonspecific DNA and to uracil-containing substrates but binds abasic sites with a Kd of <1.4 μm. This second DNA complex structure of a family I UNG gives new insight into the role of D4 as a co-factor of vaccinia virus DNA polymerase and allows a better understanding of the structural determinants required for UNG action.
D4 is a uracil-DNA glycosylase (UNG) and an essential component of the vaccinia virus DNA polymerase holoenzyme.
The crystal structure of D4 in complex with DNA is presented.
The D4·DNA contacts exhibit major differences compared with the human UNG·DNA complex.
This work allows a better understanding of the structural determinants required for UNG function.
We investigated 4 related human cases of cowpox virus infection reported in France during 2011. Three patients were infected by the same strain, probably transmitted by imported pet rats, and the ...fourth patient was infected by another strain. The 2 strains were genetically related to viruses previously isolated from humans with cowpox infection in Europe.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Highlights • A field study performed in Guinea during the West African Ebola outbreak. • Field assessment of clinical performance of the FilmArray® BioThreat-E test. • BioThreat-E test on whole blood ...was compared to two conventional RT-PCRs on serum. • Sensitivity was 95.7% 95% CI: 85.5–99.5 and specificity 100% 95% CI: 95.9–100. • Saliva might be used as a non-invasive specimen with the FA BioThreat-E test.
Mammarenaviruses bud out of infected cells via the recruitment of the endosomal sorting complex required for transport through late domain motifs localized into their Z protein. Here, we demonstrated ...that mammarenaviruses lacking this protein can be rescued and are replicative, despite a 3-log reduction in virion production, in BHK-21 cells, but not in five other cell lines. Mutations of putative late domain motifs identified into the viral nucleoprotein resulted in the almost complete abolition of infectious virion production by Z-deleted mammarenaviruses. This result strongly suggested that the nucleoprotein may compensate for the deletion of Z. These observations were primarily obtained using the Lymphocytic choriomeningitis virus, and further confirmed using the Old World Lassa and New World Machupo viruses, responsible of human hemorrhagic fevers. Z-deleted viruses should prove very useful tools to investigate the biology of Mammarenaviruses.
•Arenaviruses lacking the Z protein can be rescued and cultivated in BHK-21 cells.•Arenaviruses without Z still produce a low amount of infectious particles.•The lack of Z appears to be compensated by late domains found into the NP protein.
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°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 ~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.
1 Emerging Pathogens Laboratory, Fondation Mérieux, IFR128 BioSciences Lyon-Gerland, Lyon, France
2 Virology Laboratory, Armed Forces Biomedical Research Institute (IRBA), Emile Pardé, Grenoble, ...France
3 INSERM, P4 – Jean Mérieux Laboratory, Lyon, France
4 Institut Pasteur, Unité de Génétique Moléculaire des Bunyavirus, Paris, France
Correspondence Michèle Bouloy mbouloy{at}pasteur.fr
Crimean–Congo hemorrhagic fever virus (CCHFV) is a highly pathogenic, tick-borne member of the family Bunyaviridae and the genus Nairovirus . To better elucidate the pathogenesis of CCHFV, we analysed the host innate immune response induced in antigen-presenting cells (APCs) infected in vitro by CCHFV. Monocyte-derived dendritic cells (DCs) and macrophages (MPs) were both shown to be permissive for CCHFV and to replicate the virus, as monitored by genomic and antigenomic strand quantification. Virus replication was, however, controlled, corroborating an efficient alpha interferon-induced response. The upregulation of CD-83 and CD-86 indicated that CCHFV induced a partial maturation of DCs, which were also shown to activate the secretion of interleukin (IL)-6 and IL-8, but no tumour necrosis factor alpha (TNF- ). On the other hand, in MPs, CCHFV infection elicited a high IL-6 and TNF- response and a moderate chemokine response. Nevertheless, when we compared these APC responses with those seen after infection with Dugbe virus (DUGV), a mildly pathogenic virus genetically close to CCHFV, we found that, in spite of some similarities, DUGV induced a higher cytokine/chemokine response in MPs. These results suggest that CCHFV is able to inhibit the activation of inflammatory mediators selectively in infection in vitro and that these differences could be relevant in pathogenesis.
Two supplementary figures are available with the online version of this paper.
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