| Citation: | Jingdong Wei, Han Jiang, Zaili Zhen, Jiangbo Zhou. CRITICAL TRAVELING WAVES IN A DELAYED DIFFUSIVE EPIDEMIC SYSTEM[J]. Journal of Applied Analysis & Computation, 2026, 16(2): 1016-1034. doi: 10.11948/20250194 |
In this paper, we investigate the existence of critical traveling wave solutions in a diffusive epidemic system with delay. The existence of super-critical traveling wave solutions is well-known. By constructing suitable upper-lower solutions of wave system and applying Schauder’s fixed point theorem coupled with delicate analysis, we derive the existence of non-trivial positive bounded critical traveling wave solution for the first time. Moreover, if the transmission rate equals to the removed rate, then the nonexistence of traveling wave solutions with any positive wave velocity is obtained.
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