1. Updated Characterization of Poliovirus Transmission in Pakistan and Afghanistan and the Impacts of Different Outbreak Response Vaccine Options.
- Author
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Kalkowska DA, Pallansch MA, Cochi SL, and Thompson KM
- Subjects
- Afghanistan epidemiology, Disease Eradication, Humans, Pakistan epidemiology, Pandemics, Poliomyelitis epidemiology, Poliomyelitis prevention & control, SARS-CoV-2, COVID-19, Disease Outbreaks prevention & control, Poliomyelitis transmission, Poliovirus immunology, Poliovirus Vaccine, Oral
- Abstract
Background: Pakistan and Afghanistan remain the only reservoirs of wild poliovirus transmission. Prior modeling suggested that before the coronavirus disease 2019 (COVID-19) pandemic, plans to stop the transmission of serotype 1 wild poliovirus (WPV1) and persistent serotype 2 circulating vaccine-derived poliovirus (cVDPV2) did not appear on track to succeed., Methods: We updated an existing poliovirus transmission and Sabin-strain oral poliovirus vaccine (OPV) evolution model for Pakistan and Afghanistan to characterize the impacts of immunization disruptions and restrictions on human interactions (ie, population mixing) due to the COVID-19 pandemic. We also consider different options for responding to outbreaks and for preventive supplementary immunization activities (SIAs)., Results: The modeling suggests that with some resumption of activities in the fall of 2020 to respond to cVDPV2 outbreaks and full resumption on 1 January 2021 of all polio immunization activities to pre-COVID-19 levels, Pakistan and Afghanistan would remain off-track for stopping all transmission through 2023 without improvements in quality., Conclusions: Using trivalent OPV (tOPV) for SIAs instead of serotype 2 monovalent OPV offers substantial benefits for ending the transmission of both WPV1 and cVDPV2, because tOPV increases population immunity for both serotypes 1 and 2 while requiring fewer SIA rounds, when effectively delivered in transmission areas., (Published by Oxford University Press for the Infectious Diseases Society of America 2021.)
- Published
- 2021
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