Research Article
Global Dynamics of Infectious Disease with Arbitrary
Distributed Infectious Period on Complex Networks
Xiaoguang Zhang,
1,2
Rui Song,
2
Gui-Quan Sun,
2,3
and Zhen Jin
2,3
1
School of Mechatronic Engineering, North University of China, Taiyuan, Shanxi 030051, China
2
Department of Mathematics, North University of China, Taiyuan, Shanxi 030051, China
3
Complex Systems Research Center, Shanxi University, Taiyuan, Shanxi 030006, China
Correspondence should be addressed to Zhen Jin; jinzhn@263.net
Received 6 July 2014; Accepted 19 August 2014; Published 1 September 2014
Academic Editor: Sanling Yuan
Copyright © 2014 Xiaoguang Zhang et al. Tis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Most of the current epidemic models assume that the infectious period follows an exponential distribution. However, due to
individual heterogeneity and epidemic diversity, these models fail to describe the distribution of infectious periods precisely. We
establish a SIS epidemic model with multistaged progression of infectious periods on complex networks, which can be used to
characterize arbitrary distributions of infectious periods of the individuals. By using mathematical analysis, the basic reproduction
number
0
for the model is derived. We verify that the
0
depends on the average distributions of infection periods for diferent
types of infective individuals, which extend the general theory obtained from the single infectious period epidemic models. It is
proved that if
0
<1, then the disease-free equilibrium is globally asymptotically stable; otherwise the unique endemic equilibrium
exists such that it is globally asymptotically attractive. Finally numerical simulations hold for the validity of our theoretical results
is given.
1. Introduction
Te infectious period of an infective individual means the
period during which an infected person has a probability of
transmitting the virus to any susceptible host or vector they
contact. Note that the infectious period may be associated
with the ftness of persons. Te infuence degrees of infection
and rates of disease transmission are varied for individuals
with diferent infectious periods. Every year, some emerging
infectious diseases with unknown infectious period are seri-
ously threatening the health of people. Tere is no doubt that
the defciency of the infectious period’s knowledge results
in the difculty of controlling epidemic. Ten, in order to
obtain the date of the infectious period of these epidemics
in medicine, a large amount of statistics data is necessary.
However, it is hard to get the date in the early stage of
the disease. Terefore applying mathematical methods to
research the efects of infectious period distribution on the
infectious diseases spread is signifcative.
As the SIS compartment model was frst proposed by
Kermack and McKendrick in 1932 [1], thousands of scien-
tists successively started to study the epidemic propagation
by mathematic models [2–4]. In most of their models,
infected compartment contains all infected individuals and
the proportion of infected individuals who transit into the
next state per unit time is a constant . Wearing et al. [5]
pointed out that the assumption of exponentially distributed
infectious periods always results in underestimating the
basic reproductive ratio of an infection from outbreak data.
According to the staged progression features of HIV or
TB, Lloyd [6] applied gamma distribution to describe the
infectious period distribution. However, the distributions of
the infectious period of a lot of infectious diseases in the real
world may not satisfy exponent or gamma distribution. Ten,
Feng et al. [7] used integral-diferential equations to study
the nonexponential distribution of the infectious period. Te
homogeneous mixing models, they considered, ignore the
heterogeneity of contacts of individuals.
Hindawi Publishing Corporation
Discrete Dynamics in Nature and Society
Volume 2014, Article ID 161509, 9 pages
http://dx.doi.org/10.1155/2014/161509