Fig. 5

Impact and rebound of the prevalence of infection (a), the effective reproduction number (R _e ) (b), and the distribution of individuals according to their number of prior infections for 10 rounds of MDA (c). (a) The rate of rebound of infection increases over time but, once MDA ceases, infection initially overshoots then attains its new endemic equilibrium for both treatment regimens. (b) A similar time evolution of R _e is seen in both transmission reduction regimens: an abrupt drop with the transmission reduction, a gradual rise during MDA, followed by a fall and eventual settling to the new steady-state value. (c) The susceptible population distribution is plotted for the hyperendemic setting prior to (shaded distribution), immediately following (blue dashed line) 10 MDA rounds and 25 % transmission reduction, and immediately following (black solid line) 10 MDA rounds and 50 % transmission reduction. Note that the feint dotted grey line represents the ‘MDA only’ case with 10 treatment rounds