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Abstract Most ecological models are based on the assumption that species interact in pairs. Diverse communities, however, can have higher‐order interactions, in which two or more species jointly impact the growth of a third species. A pitfall of the common pairwise approach is that it misses the higher‐order interactions potentially responsible for maintaining natural diversity. Here, we explore the stability properties of systems where higher‐order interactions guarantee that a specified set of abundances is a feasible equilibrium of the dynamics. Even these higher‐order interactions which lead to equilibria do not necessarily produce stable coexistence. Instead, these systems are more likely to be stable when the pairwise interactions are weak or facilitative. Correlations between the pairwise and higher‐order interactions, however, do permit robust coexistence even in diverse systems. Our work not only reveals the challenges in generating stable coexistence through higher‐order interactions but also uncovers interaction patterns that can enable diversity. 

Significance Numerous factors affect early transmission by a newly infected host. A less symptomatic initial infection can persist longer due to reduced immune response, but at the cost of reduced transmission. Assuming simple trade-offs for progression and transmission rates in the initial infectious stage, we couple epidemiological and evolutionary dynamics. We find that fully asymptomatic, less symptomatic, or fully symptomatic first stages are possible evolutionary outcomes, with possible surprising bistability between zero and maximal asymptomatic behavior. This bistability implies that small changes in parameter values followed by reversion to their original values could lead to an alternative stable state with a qualitative difference in degree of first-stage symptoms. Therefore, disease control strategies can have dramatic evolutionary outcomes, cascading to epidemiological consequences.