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A simple vaccination model with multiple endemic states.

C M Kribs-Zaleta·J X Velasco-Hernández
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Abstract

A simple two-dimensional SIS model with vaccination exhibits a backward bifurcation for some parameter values. A two-population version of the model leads to the consideration of vaccination policies in paired border towns. The results of our mathematical analysis indicate that a vaccination campaign φ meant to reduce a disease's reproduction number R(φ) below one may fail to control the disease. If the aim is to prevent an epidemic outbreak, a large initial number of infective persons can cause a high endemicity level to arise rather suddenly even if the vaccine-reduced reproduction number is below threshold. If the aim is to eradicate an already established disease, bringing the vaccine-reduced reproduction number below one may not be sufficient to do so. The complete bifurcation analysis of the model in terms of the vaccine-reduced reproduction number is given, and some extensions are considered.

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AIDS VaccinesDisease OutbreaksHIV InfectionsHumansMexicoModels, ImmunologicalPublic HealthRubellaRubella VaccineUnited StatesVaccinationJournal ArticleResearch Support, Non-U.S. Gov't

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C M Kribs-Zaleta, J X Velasco-Hernández. 2000. A simple vaccination model with multiple endemic states.. https://doi.org/10.1016/s0025-5564(00)00003-1

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