Assessing the Risk of Vaccine-derived Outbreaks After Reintroduction of Oral Poliovirus Vaccine in Postcessation Settings

Figure 1.. Vaccinations and first shedding events by household. A shedding event was defined as the presence of ≥1 serotype in a stool sample, and only the first shedding event for each individual is displayed. Each row corresponds to a household, and the size of points is scaled to case numbers. Pie chart shows the cumulative number of shedding events in vaccinees, household contacts of vaccinees, and unvaccinated households. (Households that were enrolled in the Mexico study but provided no positive stool samples throughout the study period are not shown.)

Figure 2.. Shedding duration in Mexican study cohort by Sabin serotype, in vaccine recipients and naturally infected individuals.

Figure 3.. Effective reproductive number for nonvaccinees. Overall and within-household effective reproductive numbers (Re) values estimated at the onset of the Mexico study (A) and 5 years after cessation of oral poliovirus vaccine (B).

Figure 4.. Simulated outbreak response using oral poliovirus vaccine (OPV) in Capoluca 5 years after cessation. A, Predicted cumulative incidence and duration of continued transmission by Sabin serotype, according to vaccination rate among children <5 years of age. B, Sensitivity analysis on transmission rates of Sabin 2 with vaccine coverage fixed at 10%; the same multiplier is applied to within-household and between-household transmission rates. C, Sensitivity analysis on transmission rates of Sabin 2 with vaccine coverage fixed at 90%. D, Sensitivity analysis on shedding duration in children <5 years of age (born after cessation and vaccinated with inactivated poliovirus vaccine alone in routine immunization) and fraction susceptible to infection in persons >5 years of age (born before cessation and exposed to OPV viruses before). Grid color indicates median of the simulation outputs, and annotations represent nonzero probabilities (percentages) of OPV circulating for >9 months in a community. Abbreviation: CI, credible interval.

Figure 5.. Simulated silent circulation triggered by 1 infectious case shedding Sabin virus in Capoluca 5 years after cessation. A, Predicted magnitude and duration of continued transmission by serotype. Scatterplots show results of each simulation; violin plots, marginal distributions of duration and total cases. B, Sensitivity analysis on within- and between-household transmission rates of Sabin 2. Grid color indicates probability of Sabin virus circulating for >9 months in a community. C, Sensitivity analysis on shedding duration in children <5 years of age and fraction susceptible to infection in persons >5 years of age. Abbreviation: cVDPV, circulating vaccine-derived poliovirus.