Optimal control applied to Zika virus epidemics in Colombia and Puerto Rico

Wencel Valega-Mackenzie; Karen Ríos-Soto; Suzanne Lenhart

doi:10.1016/j.jtbi.2023.111647

Optimal control applied to Zika virus epidemics in Colombia and Puerto Rico

J Theor Biol. 2023 Oct 28:111647. doi: 10.1016/j.jtbi.2023.111647. Online ahead of print.

Authors

Wencel Valega-Mackenzie¹, Karen Ríos-Soto², Suzanne Lenhart³

Affiliations

¹ Department of Mathematics, University of Tennessee, Knoxville, United States of America. Electronic address: wvalegam@alumn.utk.edu.
² Department of Mathematics, University of Puerto Rico, Mayagüez, United States of America.
³ Department of Mathematics, University of Tennessee, Knoxville, United States of America.

PMID: 39492547
DOI: 10.1016/j.jtbi.2023.111647

Abstract

Zika virus (ZIKV) is a mostly non-lethal disease in humans transmitted by mosquitoes or humans that can produce severe brain defects such as microcephaly in babies and Guillain-Barré syndrome in elderly adults. The use of optimal control strategies involving information campaigns about insect repellents and condoms alongside an available safe and effective vaccine can prevent the number of infected humans with ZIKV. A system of nonlinear ordinary differential equations is formulated for the transmission dynamics of ZIKV in the presence of three control strategies to evaluate the impact of various scenarios during a ZIKV epidemic. In addition, we estimate parameters using weekly incidence data from previous ZIKV outbreaks in Colombia and Puerto Rico to capture the dynamics of an epidemic in each country when control measures are available. The basic reproduction number, R₀, of each country is calculated using estimated parameters (without the controls). The vector-borne transmission threshold (R_v) is dominant in both countries , but the sexual transmission threshold (R_d) in Colombia is considerably higher than in Puerto Rico. Numerical simulations for Colombia show that the most effective strategies are to use three controls since the start of the outbreak. However, for Puerto Rico only information campaigns about mosquito repellents and vaccination are the most effective ways to mitigate the epidemic.

Keywords: Basic reproduction number; Dynamical systems; Epidemiology; Infectious disease modeling; Optimal control theory.