Ergodicity of a Nonlinear Stochastic SIRS Epidemic Model with Regime-Switching Diffusions

<div>Simulations of the solution <svg height="11.5564pt" id="M127" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 79.8013 11.5564" width="79.8013pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M449 634C442 637 425 643 405 650C376 660 341 666 307 666C181 666 98 590 98 485C98 400 170 343 215 310L246 288C307 243 343 204 343 147C343 67 291 18 219 18C104 18 61 124 51 202L23 199C28 124 27 71 27 47C47 22 122 -16 204 -16C324 -16 428 60 428 174C428 256 379 309 307 360L276 382C223 419 179 455 179 516C179 576 221 632 293 632C379 632 410 564 418 487L448 490C446 536 446 592 449 634Z"></path></g><g transform="matrix(.013,0,0,-0.013,10.634,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 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d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"></path></g></svg> to stochastic model (<a href="https://static.hindawi.com/articles/complexity/volume-2020/4574510/figures/#EEq2">2</a>) with <span class="nowrap"><svg height="11.5564pt" id="M128" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 156.771 11.5564" width="156.771pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M449 634C442 637 425 643 405 650C376 660 341 666 307 666C181 666 98 590 98 485C98 400 170 343 215 310L246 288C307 243 343 204 343 147C343 67 291 18 219 18C104 18 61 124 51 202L23 199C28 124 27 71 27 47C47 22 122 -16 204 -16C324 -16 428 60 428 174C428 256 379 309 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Complexity

fig2

Figure 2

Figure 2: Ergodicity of a Nonlinear Stochastic SIRS Epidemic Model with Regime-Switching Diffusions 