Fig. 3.

Model-estimated median shedding index endpoint (SIE) of shed poliovirus (type 2) by country as a function of neutralizing antibody titers pre-mOPV2 challenge and nominal day post-challenge of stool sample collection for the subset analysis of IPV001 participants only. Faint line indicates regression fit to observed data ignoring censoring at NAb LLOQ (2.5 log₂) and ULOQ (10.5 log₂); bold line indicates aggregated median regression fit predictions from simulation method to account for censoring. Observed data points are jittered to convey density. Figure is limited to observed range of data due to poor performance of the spline fit at the low-sample-size extremes of the NAb range.