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Updated: Feb 11, 2026

Production and Purification of Non Replicative Canine Adenovirus Type 2 Derived Vectors
Published on: December 3, 2013
The detection of 3 ambiguous type 2 vaccine-derived polioviruses (VDPV2s) in Uganda
Mary Bridget Nanteza1, Barnabas Bakamutumaho2, Annet Kisakye3
1Uganda Virus Research Institute (UVRI), Plot 51 - 59 Nakiwogo Road, P. O. Box 49, Entebbe, Uganda. marybridgetnanteza@yahoo.com.
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.
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