Molecular and Phenotypic Characterization of a Highly Evolved Type 2 Vaccine-Derived Poliovirus Isolated from Seawater in Brazil, 2014

PLoS One. 2016 Mar 28;11(3):e0152251. doi: 10.1371/journal.pone.0152251. eCollection 2016.


A type 2 vaccine-derived poliovirus (VDPV), differing from the Sabin 2 strain at 8.6% (78/903) of VP1 nucleotide positions, was isolated from seawater collected from a seaport in São Paulo State, Brazil. The P1/capsid region is related to the Sabin 2 strain, but sequences within the 5'-untranslated region and downstream of the P1 region were derived from recombination with other members of Human Enterovirus Species C (HEV-C). The two known attenuating mutations had reverted to wild-type (A481G in the 5'-UTR and Ile143Thr in VP1). The VDPV isolate had lost the temperature sensitive phenotype and had accumulated amino acid substitutions in neutralizing antigenic (NAg) sites 3a and 3b. The date of the initiating OPV dose, estimated from the number of synonymous substitutions in the capsid region, was approximately 8.5 years before seawater sampling, a finding consistent with a long time of virus replication and possible transmission among several individuals. Although no closely related type 2 VDPVs were detected in Brazil or elsewhere, this VDPV was found in an area with a mobile population, where conditions may favor both viral infection and spread. Environmental surveillance serves as an important tool for sensitive and early detection of circulating poliovirus in the final stages of global polio eradication.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5' Untranslated Regions
  • Amino Acid Sequence
  • Amino Acid Substitution
  • Antibodies, Viral / immunology
  • Brazil
  • Capsid Proteins / genetics
  • Capsid Proteins / metabolism
  • Cell Line
  • Humans
  • Molecular Sequence Data
  • Phenotype
  • Phylogeny
  • Poliovirus / classification
  • Poliovirus / isolation & purification
  • Poliovirus / metabolism*
  • Promoter Regions, Genetic
  • Real-Time Polymerase Chain Reaction
  • Recombination, Genetic
  • Seawater / virology*
  • Sequence Alignment
  • Temperature


  • 5' Untranslated Regions
  • Antibodies, Viral
  • Capsid Proteins

Grants and funding

KMSMC was supported by the “Conselho Nacional de Desenvolvimento Científico e Tecnológico” (URL: The study was supported by the "Fundação Oswaldo Cruz" (URL: and CNPq. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.