Fig. 1

Model description. A Compartment model diagram outlining three disease states each with two age compartments: one younger, potentially reproductive, and one post-reproductive. B Functional dependence on the population age structure for the fraction of younger hosts which reproduce under collaborative, \(a=0, 0<b\le \frac{1}{2}\), and competitive,\(b=0 , 0<a\le \frac{1}{2}\), conditions