Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission

• 作者: Nelson Owuor Onyango
• 来源期刊: 应用数学(英文)
• 学科: 医学
• 关键词: SEIR EPIDEMIC MODELS ENDEMIC Equilibriums HEPATITIS B
• 年，卷（期）: 2014,（16）
• 页码范围: 2518-2529
• 页数: 12页
• 分类号: R73

摘要

This paper examines the dynamics of Hepatitis B via a Susceptible Exposed Infectious Recovered (SEIR) type epidemic model. Previous studies have shown that Hepatitis B is characterized by multiple endemic solutions, a matter which may be of concern in developing control strategies. We identify the possible causes of multiple endemic solutions in a Hepatitis B model and conclude that the dependance of the probability of carriage development ?(q(Λ)) on the force of infection (Λ) is the main reason for multiple endemicity. Other factors such as a large proportion of infants that are not vaccinated (ω) may also enhance the possibility of multiple endemicity. The role of carriers may also play a key role in the possibility of such complex dynamics, i.e., when infectiousness of carriers-(α)?is high, the probability of existence of multiple endemic equilibrium solutions is increased. In our arguments, the traditional reproduction number R0G(0) < 1 does not imply stability of disease-free equilibrium.