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Available from: Dominique Rousset
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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.
    Full-text · Article · Sep 2011 · PLoS ONE
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    • "Consequently, the vaccine is associated with a low rate of paralytic poliomyelitis (vaccine-associated paralytic poliomyelitis ; VAPP) (Dowdle et al., 2003). Further, polioviruses can also circulate invisibly without symptomatic patients in the population for several months and then revert from the attenuating form to a neurovirulent one (vaccine-derived polioviruses; VDPVs), causing outbreaks (Kew et al., 2002; Liang et al., 2006; Rousset et al., 2003; Shimizu et al., 2004; Yang et al., 2003). "
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    ABSTRACT: A type 2 vaccine-derived poliovirus (VDPV) (strain CHN1025), with a 1.1 % (10/903) difference from Sabin strain in the VP1 coding region, was isolated from a child with poliomyelitis caused by a poliovirus variant infection. The patient was from Shandong Province of China and developed acute flaccid paralysis in 1997. The child was infected with a rare and complicated penta-recombinant poliovirus with the uncommon genomic recombinant organization S2/S3/S1/S3/S1/S3. At least five successive rounds of recombination occurred in the VP1 capsid coding region and in the 2C, 3C (twice) and 3D(pol) non-capsid coding regions, respectively, during virus evolution. Strain CHN1025 had most of the characteristics of the type 2 vaccine strain; it had Sabin-specific epitopes, suggesting that the virus was antigenically indistinguishable from the Sabin 2 reference strain. Typical mutations in the 5'-untranslated region and VP1 associated with reversion to neurovirulence for Sabin 2 poliovirus were found, and the virus showed moderate neurovirulence in transgenic mice. A few nucleotide substitutions were located in the donor sequences, and two donor sequences contained no nucleotide substitutions, suggesting that these sequences were relatively new. The appearance of these mutations within approximately 192 days of at least five successive rounds of recombination events derived from a single ancestral infection illustrates the rapid emergence of new recombinants among VDPVs. This is the first report on the isolation of a type 2/type 3 poliovirus capsid recombinant with one of the five crossover sites located in the VP1 coding region.
    Full-text · Article · Oct 2009 · Journal of General Virology
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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.
    Full-text · Article · May 2009
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