Hypothetical emergence of poliovirus in 2020: part 2. exploration of the potential role of vaccines in control and eradication

Abstract

Objectives:The emergence of human pathogens with pandemic potential motivates rapid vaccine development. We explore the role of vaccines in control and eradication of a novel emerging pathogen. Methods: We hypothetically simulate emergence of a novel wild poliovirus (nWPV) in 2020 assuming an immunologically naïve population. Assuming different nonpharmaceutical interventions (NPIs), we explore the impacts of vaccines resembling serotype-specific oral poliovirus vaccine (OPV), novel OPV (nOPV), or inactivated poliovirus vaccine (IPV). Results: Vaccines most effectively change the trajectory of an emerging disease when disseminated early, rapidly, and widely in the background of ongoing strict NPIs, unless the NPIs successfully eradicate the emerging pathogen before it establishes endemic transmission. Without strict NPIs, vaccines primarily reduce the burden of disease in the remaining susceptible individuals and in new birth cohorts. Live virus vaccines that effectively compete with the nWPVs can reduce disease burdens more than other vaccines. When relaxation of existing NPIs occurs at the time of vaccine introduction, nWPV transmission can counterintuitively increase in the short term. Conclusions: Vaccines can increase the probability of disease eradication in the context of strict NPIs. However, successful eradication will depend on specific immunization strategies used and a global commitment to eradication.

Hypothetical emergence of poliovirus in 2020: part 1. Consequences of policy decisions to respond using nonpharmaceutical interventions

“…Current modeling for polio and performance of the GPEI to date provide relevant context about the actual situation [50,79]. In addition, for this hypothetical analysis, we implicitly assumed no availability of vaccines at the time of emergence, and we refer to a separate analysis that explores the potential impact of vaccines [80].…”

Pandemic refuges: Lessons from 2 years of COVID‐19

“…Western Australia's refuge policy can be interpreted as a success in the sense that it maintained near‐zero pathogen spread until the state was prepared to handle the spread and long after it was clear that the pandemic would not constitute an extreme global catastrophe. Prior research has found synergies between vaccines and nonpharmaceutical interventions such as refuges for the control of infectious diseases (Thompson et al., 2021b ). Western Australia's experience in COVID‐19 demonstrates the value of this approach.…”

Kimberly M. Thompson: Managing global disease risks and improving children's lives

“…Many of her other favorite projects focus on variability and uncertainty in risk in support decision making (Thompson & Graham, 1996), value of information modeling (Thompson & Evan, 1997), dynamic modeling of a surprising paraoccupational risk (Thompson & Evans, 1993), the impact of variability on groundling risks (Thompson et al., 2001), and content analyses of entertainment media (Thompson & Haninger, 2001; Yokota & Thompson, 2000) marketed to children. A recent favorite applied the global polio model to ask the questions: What if polio emerged for the first time in late 2019 instead of COVID‐19 and what might we expect from vaccines (Thompson et al., 2021b, 2021c)?…”