Multiple Transmission Pathways and Disease Dynamics in a Waterborne Pathogen Model |
| |
Authors: | Joseph H Tien David J D Earn |
| |
Institution: | (1) Computational Epidemiology Research Laboratory, Department of Computer Science and Engineering, University of North Texas, Denton, TX 76203, USA;(2) Dallas Regional Campus, University of Texas School of Public Health, Dallas, TX 75390, USA |
| |
Abstract: | Multiple transmission pathways exist for many waterborne diseases, including cholera, Giardia, Cryptosporidium, and Campylobacter. Theoretical work exploring the effects of multiple transmission pathways on disease dynamics is incomplete. Here, we consider
a simple ODE model that extends the classical SIR framework by adding a compartment (W) that tracks pathogen concentration in the water. Infected individuals shed pathogen into the water compartment, and new
infections arise both through exposure to contaminated water, as well as by the classical SIR person–person transmission pathway.
We compute the basic reproductive number (ℛ0), epidemic growth rate, and final outbreak size for the resulting “SIWR” model, and examine how these fundamental quantities
depend upon the transmission parameters for the different pathways. We prove that the endemic disease equilibrium for the
SIWR model is globally stable. We identify the pathogen decay rate in the water compartment as a key parameter determining
when the distinction between the different transmission routes in the SIWR model is important. When the decay rate is slow,
using an SIR model rather than the SIWR model can lead to under-estimates of the basic reproductive number and over-estimates
of the infectious period. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|