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🦍biological anthropology review

Vaccine-derived poliovirus

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Vaccine-derived poliovirus (VDPV) refers to a strain of the poliovirus that has mutated from the live attenuated virus used in the oral polio vaccine (OPV). While OPV is designed to provide immunity and prevent poliovirus transmission, in rare cases, the weakened virus can revert to a more virulent form, leading to outbreaks of poliomyelitis. This phenomenon connects to the broader understanding of infectious diseases and the human immune system, as it highlights the delicate balance between vaccination benefits and potential risks associated with live vaccines.

5 Must Know Facts For Your Next Test

  1. VDPV can arise in areas with low vaccination coverage, where the virus has the opportunity to circulate among unvaccinated populations.
  2. There are three types of VDPV: circulating VDPV (cVDPV), which spreads in communities, and two types of rare VDPV that can emerge sporadically.
  3. Outbreaks of VDPV have been documented in various countries, often leading to paralysis cases similar to those caused by wild poliovirus.
  4. The Global Polio Eradication Initiative has shifted strategies in response to VDPV occurrences, promoting enhanced surveillance and switching from OPV to inactivated polio vaccine (IPV) in some regions.
  5. Monitoring and controlling VDPV is crucial for achieving global eradication of poliovirus, as it poses a challenge in maintaining high vaccination coverage.

Review Questions

  • How does vaccine-derived poliovirus occur and what factors contribute to its emergence?
    • Vaccine-derived poliovirus occurs when the live attenuated virus used in the oral polio vaccine mutates into a more virulent form. Factors contributing to its emergence include low vaccination coverage, allowing the weakened virus to circulate among unvaccinated individuals. In such environments, the chances of mutation increase, which can lead to outbreaks that resemble those caused by wild poliovirus.
  • Discuss the implications of vaccine-derived poliovirus on public health strategies for polio eradication.
    • The presence of vaccine-derived poliovirus significantly impacts public health strategies aimed at eradicating polio. Outbreaks of VDPV highlight the necessity for robust vaccination programs and increased surveillance to monitor both wild and vaccine-derived strains. The Global Polio Eradication Initiative has had to adapt by promoting a transition from oral polio vaccine to inactivated polio vaccine in certain regions, ensuring better control over potential VDPV cases while maintaining population immunity.
  • Evaluate the challenges posed by vaccine-derived poliovirus in achieving global polio eradication goals and suggest potential solutions.
    • The challenges posed by vaccine-derived poliovirus include the risk of outbreaks in under-vaccinated populations and the complexity of managing both wild and VDPV strains. To address these issues, increasing vaccination coverage and implementing effective surveillance systems are critical. Additionally, transitioning to the inactivated polio vaccine in high-risk areas could reduce the likelihood of VDPV emergence. Engaging communities to promote awareness about vaccination benefits is also essential for sustaining high immunization rates.