Fig. 2: Transmission dynamics of MPXV clade I outbreaks.
From: Role of community and sexual contacts as drivers of MPXV clade I
a, Age-specific transmission patterns inferred for clade Ia in endemic provinces of the DRC and clade Ib in North and South Kivu and Burundi. The colours represent daily transmission rates between infector–infectee pairs in given age groups according to the estimated next-generation matrices. b, Projected time-evolving effective reproduction numbers (Ry) for clades Ia and Ib in the DRC (blue lines) and Burundi (red lines) from 2010 to 2030. The lines and shaded areas represent median estimates and 95% credible intervals of Ry, respectively. The estimated reproduction number of 0.82 (95% confidence interval = 0.79–0.85) from the clade Ia case data between 2013 and 2017 in Tshuapa province in the DRC15 was used as a reference value for 2015 (the midpoint of the study period), denoted by horizontal whiskers. The empirical estimates of the effective reproduction number from the DRC incidence data in the pre-clade Ib period in 2023 (pre-Ib) and from the South Kivu incidence data (SK) in 2024, as proxy data for clades Ia and Ib, respectively, are displayed as dots (medians and 95% credible intervals) for comparison. Paired dots (jittered horizontally for visual aid) denote the different serial interval distributions used, which were estimated elsewhere from two separate sets of infector–infectee pairs (distribution 1: mean = 17.5 days; distribution 2: mean = 11.4 days)77. The dashed horizontal line denotes the epidemic threshold value of 1. c, Contour plots for the estimated impact (percentage reduction in reproduction number (left) and reproduction number (right)) of different combinations of FSW-focused and mass vaccination strategies on the effective reproduction number in the Kivus. Note that the axes represent very different scales in the absolute number of doses, reflecting population sizes for FSWs and general adults.
