The detection of 3 ambiguous type 2 vaccine-derived polioviruses (VDPV2s) in Uganda

Virol J. 2018 Apr 27;15(1):77. doi: 10.1186/s12985-018-0990-y.

Abstract

Background: The Oral Polio Vaccine (OPV or Sabin) is genetically unstable and may mutate to form vaccine-derived polioviruses (VDPVs).

Methods: In 2014, two VDPVs type 2 were identified during routine surveillance of acute flaccid paralysis (AFP) cases. Consequently, a retrospective VDPV survey was conducted to ensure that there was no circulating VDPV in the country. All Sabin poliovirus isolates identified in Uganda 6 months before and 6 months after were re-screened; Sabin 1 and 3 polioviruses were re-screened for Sabin 2 and Sabin 2 polioviruses were re-screened for VDPVs type 2. The Poliovirus rRT-PCR ITD/VDPV 4.0 assay and sequencing were used respectively.

Results: The first two VDPVs type2 were identified in Eastern Uganda and the third was identified during the survey from South-western Uganda. These regions had low OPV coverage and poor AFP surveillance indicators.

Conclusion: The retrospective VDPV survey was a useful strategy to screen for VDPVs more exhaustively. Supplementary surveillance methods need to be encouraged.

Keywords: Immunization; Poliovirus; Uganda; Vaccine-derived poliovirus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Capsid Proteins / genetics
  • Epidemiological Monitoring
  • Female
  • Humans
  • Infant
  • Male
  • Mutation
  • Phylogeny
  • Poliomyelitis / prevention & control
  • Poliomyelitis / virology*
  • Poliovirus / classification*
  • Poliovirus / genetics
  • Poliovirus / isolation & purification*
  • Poliovirus Vaccine, Oral / adverse effects
  • Retrospective Studies
  • Uganda
  • Vaccines, Attenuated / administration & dosage
  • Vaccines, Attenuated / adverse effects

Substances

  • Capsid Proteins
  • Poliovirus Vaccine, Oral
  • VP1 protein, Poliovirus
  • Vaccines, Attenuated