Characterization of a Highly Evolved Vaccine-Derived Poliovirus Type 3 Isolated from Sewage in Estonia

Abstract

Two types of vaccine-derived polioviruses have been recently designated to emphasize the different origins of the evolved viruses: circulating vaccine-derived polioviruses (cVDPV) associated with outbreaks of paralytic disease and strains isolated from chronically infected immunodeficient individuals (iVDPV). We describe here a type 3 VDPV (PV3/EST/02/E252; later E252) isolated from sewage collected in Tallinn Polioviruses, members of the Enterovirus genus in the Picornaviridae family, are important human pathogens causing the acute paralytic disease poliomyelitis. The worldwide program for eradication of wild-type poliovirus is coordinated by the World Health Organization (WHO). The program includes two simultaneous approaches: intensive immunizations mainly with the trivalent oral poliovirus vaccine (OPV) (35) and systematic surveillance of the remaining cases. The surveillance includes, most importantly, epidemiological and virological investigation of acute flaccid paralytic (AFP) cases. The AFP surveillance is supplemented in some countries by analysis of poliovirus circulation in human populations through investigation of wastewater specimens contaminated with human fecal materials (environmental surveillance) and/or by scrutinizing the results of routine virus diagnostics (enterovirus surveillance).The evolution rate of polioviruses is very high, partly due to the high error frequency in RNA synthesis: roughly 10 Ϫ4 per base pair per replication cycle. For wild polioviruses circulating in human populations, nucleotide substitutions accumulate at a rate of approximately 1% per year and consist primarily of changes at synonymous codon positions thus not leading to amino acid substitutions (22). The genetic diversity of poliovirus strains is exploited in molecular epidemiology, a key component of poliovirus surveillance (33), currently based on sequence analysis of the VP1 coding region of the genome. The

Molecular characterization of human rotavirus vaccine strain CDC-9 during sequential passages in vero cells

“…Genes of some wild-type viruses such as rotaviruses, [22][23][24][25] poliovirus, [26][27][28] varicella zoster virus, 29 porcine reproductive and respiratory syndrome virus 30 and transmissible gastroenteritis virus 31 and their attenuated forms derived by sequential passages in cell culture have been characterized to determine the molecular basis of attenuation. In this study, we isolated a G1P [8] human rotavirus strain CDC-9 from a child who had a mixed rotavirus G1P [8] and G2P [4] infection.…”

Role of environmental poliovirus surveillance in global polio eradication and beyond

“…Frequent isolation by ENV of vastly drifted aVDPV strains genetically resembling iVDPV [47,[49][50][51] suggests that long-term PV excretion is not limited to immunedeficient individuals known to the health system, or if known to the health system not recognized as chronically excreting PV.…”

Comparison of poliovirus recombinants: accumulation of point mutations provides further advantages

“…Wild-type and OPV strains have been reported to recombine (Dahourou et al, 2002;Georgescu et al, 1995;Guillot et al, 2000;Liu et al, 2000Liu et al, , 2003Yang et al, 2003) and PVs have been shown to recombine with serotypes of HEV-C (Brown et al, 2003;Jiang et al, 2007;Rousset et al, 2003). Furthermore, vaccine-derived PV strains, defined as having more than 1 % nucleotide differences in the VP1 protein coding region (reviewed recently by Agol, 2006;Kew et al, 2004), have been reported to have an interserotypic recombinant genome (Blomqvist et al, , 2004Martin et al, 2002) as well as a recombinant genome with a non-structural region from an unknown HEV-C strain (Arita et al, 2005;Kew et al, 2002Kew et al, , 2004Rakoto-Andrianarivelo et al, 2008;Rousset et al, 2003;Shimizu et al, 2004). The enterovirus recombination sites are located in the 59 non-coding region (NCR) and in the non-structural part of the 7500 nt genome in genes coding for proteins 2A, 2B, 2C and 3D.…”