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Available from: Dominique Rousset, Aug 28, 2015
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    • "In previous works [14], [20], we reported the characterization of type 2 VDPV responsible for 4 human cases of acute flaccid paralysis in humans in the south-western part of Madagascar (Tolagnaro district) in 2002. Investigations of healthy children to identify the enteroviruses circulating in the small area in which the poliomyelitis cases occurred revealed the presence of highly diverse HEV-C genomes in this region, with a high frequency of co-infections with viruses of different types. "
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    ABSTRACT: Recombination events between human enteroviruses (HEV) are known to occur frequently and to participate in the evolution of these viruses. In a previous study, we reported the isolation of a panel of viruses belonging to the Human enterovirus species C (HEV-C) that had been cocirculating in a small geographic area of Madagascar in 2002. This panel included type 2 vaccine-derived polioviruses (PV) that had caused several cases of acute flaccid paralysis in humans. Previous partial sequencing of the genome of these HEV-C isolates revealed considerable genetic diversity, mostly due to recombination. In the work presented herein, we carried out a more detailed characterization of the genomes of viruses from this collection. First, we determined the full VP1 sequence of 41 of these isolates of different types. These sequences were compared with those of HEV-C isolates obtained from other countries or in other contexts. The sequences of the Madagascan isolates of a given type formed specific clusters clearly differentiated from those formed by other strains of the same type isolated elsewhere. Second, we sequenced the entire genome of 10 viruses representing most of the lineages present in this panel. All but one of the genomes appeared to be mosaic assemblies of different genomic fragments generated by intra- and intertypic recombination. The location of the breakpoints suggested potential preferred genomic regions for recombination. Our results also suggest that recombination between type HEV-99 and other HEV-C may be quite rare. This first exhaustive genomic analysis of a panel of non-PV HEV-C cocirculating in a small human population highlights the high frequency of inter and intra-typic genetic recombination, constituting a widespread mechanism of genetic plasticity and continually shifting the HEV-C biodiversity.
    PLoS ONE 09/2011; 6(9):e24823. DOI:10.1371/journal.pone.0024823 · 3.23 Impact Factor
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    • "However, poliomyelitis associated with mutated and pathogenic PV strains derived from the oral polio vaccine (OPV) resulting vaccine-derived poliovirus (VDPV) causes increasing concern. Outbreaks of poliomyelitis associated with VDPV recently occurred in Egypt (Yang et al., 2003), Hispaniola (Kew et al., 2002), Philippines (Shimizu et al., 2004) and Madagascar (Rousset et al., 2003). The strains implicated in these 4 outbreaks were recombinant between vaccine polioviruses and unknown EVs that could be either wild polioviruses or HEV- C. "
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    ABSTRACT: Human Enteroviruses (HEVs), members of the ge-nus Enterovirus, family Picornaviridae, are the major cause of variety illnesses, such as poliomyelitis, acute flaccid paralysis, aseptic meningitis and hand-foot-and-mouth disease, especially in young child-ren. Virus isolation and neutralization tests are usually performed to identify the serotype of HEVs, but these tests are labor intensive and time consum-ing. At present, molecular methods allowing the rap-id and specific detection of HEVs are being used. Since the sequence identity of HEVs VP1 region has been shown to be well correlated with the sero-type, this VP1 sequence is often used for serotyping of HEVs. This study was aimed to identify the circu-lating HEVs among healthy children in Antajaya, one of the regions with poor sanitation in Bogor, directly from stool samples. The Reverse-Transcription seminested Polymerase Chain Reac-tion (RT-snPCR) and CODEHOP specific primers which able to amplify almost all of HEVs VP1 region, was used. The phylogenetic tree was constructed by the neighbor-joining method on the basis of VP1 sequences. A hundred and two samples were col-lected and 53 (52.0%) samples were positive for PCR. Thirty of 53 (56.6%) EVs-positive samples were analyzed and identified as Echovirus 21 (30.0%), Coxsackievirus A24 (23.3%), Coxsackievi-rus B4 (10.0%), Coxsackievirus B3 (10.0%), Echovi-rus 25 (16.6%), Echovirus 9 (3.3%), Echovirus 14 (3.3%) and Coxsackievirus A10 (3.3%). Thus, Cox-sackievirus A24 that might be able to recombine with polioviruses causing vaccine associated para-lytic poliomyelitis was dominantly circulating in the population.
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    • "One of the major advantages of oral poliovirus vaccine is that OPV strains have the capacity to spread to unimmunized individuals, effectively blocking the transmission of wild-type poliovirus in a given community. However, this advantage has proved to be a drawback, as it was the underlying cause of recent cVDPV outbreaks in regions with gaps in OPV coverage (Kew et al., 2002; Rousset et al., 2003; Shimizu et al., 2004). "
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    ABSTRACT: The genetic properties of strain K/2002, isolated from fecal samples of a 7-month-old child who had received his first oral poliovirus vaccine (OPV) dose at the age of 3 months, are described. Preliminary sequencing characterization of isolate K/2002 revealed an S3/S2 recombination event at the 3' end of the VP1 coding region. A recombination event resulted in the introduction of six Sabin 2 amino acid residues in a Sabin 3 genomic background. Furthermore, mutations associated with loss of the attenuated phenotype of Sabin 3 strains have been identified in the genome of isolate K/2002. The data presented here emphasize the need for careful planning of vaccination strategies, which involve stopping OPV administration in regions that are certified to be polio-free.
    FEMS Immunology & Medical Microbiology 05/2008; 52(3):343-51. DOI:10.1111/j.1574-695X.2008.00381.x · 2.55 Impact Factor
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