Abstract

BackgroundGenetic characterisation of polioviruses remains highly important even in countries where wild poliovirus circulation has been interrupted. Sequence data on representative wild strains from all geographical regions is required for surveillance purposes and surveillance for vaccine-related isolates with increased potential for transmissibility in humans should continue. ObjectiveTo report the genetic characteristics of wild and vaccine-related polioviruses isolated in Tunisia from 1991 to 2006. Study designWild isolates were sequenced in the VP1 genomic region and compared to each other. Vaccine-related isolates were assessed for genetic recombination by PCR/RFLP and sequence analysis of the 3D region. Recombinant viruses were assessed for genetic drift in the VP1 region. ResultsThe VP1 sequences of the last wild isolates, all from serotype3, showed 97.7–98.7% nucleotide homology. Nineteen percent of vaccine-related isolates were vaccine/vaccine intertypic recombinants. No recombinant with non-poliovirus enteroviruses was identified. Mutational differences in the VP1 sequences of recombinant viruses ranged from 0.0% to 0.7% indicating a limited replication period. ConclusionsThis study provides sequence data on wild polioviruses from Tunisia/North Africa and shows that in countries with continuous high vaccine coverage transmission of vaccine-related polioviruses is time-limited.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.