title: High resolution identity testing of inactivated poliovirus vaccines.
abstract: BACKGROUND
  Definitive identification of poliovirus strains in vaccines is essential for quality control, particularly where multiple wild-type and Sabin strains are produced in the same facility. Sequence-based identification provides the ultimate in identity testing and would offer several advantages over serological methods.
  
  
  METHODS
  We employed random RT-PCR and high throughput sequencing to recover full-length genome sequences from monovalent and trivalent poliovirus vaccine products at various stages of the manufacturing process.
  
  
  RESULTS
  All expected strains were detected in previously characterised products and the method permitted identification of strains comprising as little as 0.1% of sequence reads. Highly similar Mahoney and Sabin 1 strains were readily discriminated on the basis of specific variant positions. Analysis of a product known to contain incorrect strains demonstrated that the method correctly identified the contaminants.
  
  
  CONCLUSIONS
  Random RT-PCR and shotgun sequencing provided high resolution identification of vaccine components. In addition to the recovery of full-length genome sequences, the method could also be easily adapted to the characterisation of minor variant frequencies and distinction of closely related products on the basis of distinguishing consensus and low frequency polymorphisms.
authors.affiliation: Division of Virology, National Institute for Biological Standards and Control, Medicines and Healthcare products Regulatory Agency, South Mimms EN6 3QG, Hertfordshire, UK. Electronic address: edward.mee@nibsc.org.
authors.forename: Edward T
authors.initials: ET
authors.lastname: Mee
authors.affiliation: Division of Virology, National Institute for Biological Standards and Control, Medicines and Healthcare products Regulatory Agency, South Mimms EN6 3QG, Hertfordshire, UK.
authors.forename: Philip D
authors.initials: PD
authors.lastname: Minor
authors.affiliation: Division of Virology, National Institute for Biological Standards and Control, Medicines and Healthcare products Regulatory Agency, South Mimms EN6 3QG, Hertfordshire, UK.
authors.forename: Javier
authors.initials: J
authors.lastname: Martin
mesh_terms: D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006801:Humans; D017955:Poliovirus / Q000235:genetics*; D011054:Poliovirus Vaccine, Inactivated / Q000235:genetics* / Q000302:isolation & purification; D011786:Quality Control; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D013678:Technology, Pharmaceutical / Q000379:methods*
chemical_list: D011054:Poliovirus Vaccine, Inactivated
keywords: Deep sequencing; IPV; Inactivated poliovirus vaccine; Vaccine contamination