Discipline: Mathematics and Statistics
Subcategory: Mathematics and Statistics
Session: 1
Room: Park Tower 8211
Omomayowa Olawoyin - University of Texas at Arlington
Co-Author(s): Christopher Kribs, University of Texas at Arlington, Arlington, TX
Since 2015, Zika has been reported in over 50 countries in the Americas including the United States and has been associated with serious clinical implications such as Guillain-Barré syndrome and increased microcephaly in newborns. Although the Zika virus (ZIKV) is transmitted to humans primarily through the bite of infected female Aedes aegypti mosquitoes, it can also be sexually and vertically transmitted within both populations. Since little is known about Zika, mathematical models are essential to understanding the transmission dynamics of the disease, deriving key epidemiological quantities, and informing the creation of disease control strategies. In contrast to previous modeling studies which focus on at most two transmission pathways of the ZIKV, we introduce a new mathematical model that incorporates (1) sexual and (2) vertical ZIKV transmission within mosquito populations as well as (3) sexual transmission in humans and (4) vector to human transmission. By analyzing the simultaneous ZIKV transmission cycles in humans and vectors, something which no other model has done, we aim to answer the following research question: what is the relative contribution of the individual and combined transmission mechanisms (1-4) on the spread of Zika? Analysis of our deterministic model (which utilizes a system of nonlinear ordinary differential equations) shows that the secondary transmission routes of Zika increase the basic reproductive number of the virus (i.e. the expected number of secondary cases produced by a single infection in a completely susceptible population) by 5%, shift the peak time of an outbreak to occur 10% sooner, and have important consequences for Zika control strategies. Furthermore, sensitivity analysis show that the basic reproductive number is most sensitive to the mosquito biting rate and transmission probability parameters and reveal that the dynamics of juvenile mosquito stages greatly impact the peak time of an outbreak. These discoveries deepen our understanding of the complex transmission routes of ZIKV and the consequences that they may hold for public health officials. Future research involves validation of the model using Zika incidence data and vector control strategies of specific regions. References: Gao, D., Lou, Y., He, D., Porco, T.C., Kuang, Y., Chowell, G., & Ruan, S. Prevention and control of Zika as a mosquito-borne and sexually transmitted disease: a mathematical modeling analysis. ScientificReports 6 (2016) 28070. Olawoyin, O., & Kribs, C. (in press). Effects of multiple transmission pathways on Zika dynamics. Infectious Disease Modelling.
Funder Acknowledgement(s): This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. 1261006320.
Faculty Advisor: Christopher Kribs, kribs@mathed.uta.edu
Role: I conducted this research as part of my dissertation work. I did the literature search, developed and analyzed the model, gathered parameter values, and wrote the research manuscript.