Fig. 1: Estimating the protection from using MVA-BN in a one versus two-dose schedule.
From: Optimal deployment of limited vaccine supplies to control mpox outbreaks
A The previously reported vaccine effectiveness of first-generation vaccinia immunisation, and one and two dose MVA-BN vaccination (against clade IIb virus) from a systematic review and meta-analysis of the available data4. B The predicted vaccine effectiveness over time for one dose, two doses spaced 4 weeks apart, and delayed two dose (administered at 2 years). These predictions are from reference4, where a model-based meta-analysis was performed that linked reports of vaccinia-binding antibody titres after MVA-BN vaccination and real-world effectiveness studies, and vaccine effectiveness over time was extrapolated by assuming these binding titres predict vaccine effectiveness (which is not yet confirmed). C Schematic of potential vaccine allocation options assuming additional vaccine is available 4 weeks after primary vaccination (top) or at some later timepoint (bottom). In each case we compare the outcome of either giving a second dose to those already vaccinated or allocating the additional vaccine as first doses to a naïve population. D The ratio of cases averted by administering a first dose to naïve individuals compared to a second dose (when deployment is 4 weeks after the first doses), measured over the first 2 years after vaccination. The ratio does not vary much over the time interval being considered. E The ratio of cases averted by giving a one dose regimen rather than a two-dose regimen, estimated using the vaccine effectiveness observed in a meta-analysis of real world effectiveness studies4 (left, black) or predicted from a model-based meta-analysis using predictions of waning and different dose spacing4. Note that the analysis here assumes a low and constant force of infection. Also, in the case of giving a second dose at 26 and 52 weeks we make the assumption that peak antibody binding titres and decay in titres will resemble that seen after giving a second dose at 2 years (the only delayed interval for which immunogenicity data was available4). This assumption inflates the predicted benefit of the two-dose regimen. Shaded regions (D) and error bars (A, E) indicate 95% credible intervals.
