TITLE:
Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission
AUTHORS:
Nelson Owuor Onyango
KEYWORDS:
SEIR Epidemic Models, Endemic Equilibriums, Hepatitis B
JOURNAL NAME:
Applied Mathematics,
Vol.5 No.16,
September
2,
2014
ABSTRACT:
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)