EPIDEMIC MODEL;
AGE STRUCTURE;
SEMIGROUP;
MONOTONE OPERATOR;
GLOBAL BEHAVIOR;
D O I:
10.1137/0522069
中图分类号:
O29 [应用数学];
学科分类号:
070104 ;
摘要:
The global behavior of the general s --> i --> s age-structured epidemic model in a population of constant size is obtained. It is shown that there is a sharp threshold which determines the existence and global stability of an endemic state; hence, periodic solutions are ruled out. The threshold is identified as the spectral radius of a positive linear operator. The analysis employs the theory of semigroups and positive operator methods, and is based on the formulation of the problem as an abstract differential equation in a Banach space.