This paper concerns a disease transmission model with incubation and
infection age.Analytical results are obtained using a Lyapunov
function of the respective ratios of susceptible,expose,and
asymptomatic classes to the clinical symptomatic infective class.
Conditions are given for stability of equilibria to classify when
the disease spread to the whole population or a lesser outbreak
where some member of the population remain uninfected.

1. Abstract
2. Introduction
3. The Model
4. Some Analysis of Model
5. Discussions

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