P. DAS ET AL.

50

the endemic equilibrium point is unstable for both the

continuous time model and discrete time model.

6. Discussion

The analytical results and numerical findings of the paper

suggest the removable rate of population from incubated

class (β) which plays an important role on the dynamics

of the system. The disease free equilibrium approaches to

the endemic equilibrium when β is above a certain thre-

shold value and on the contrary the endemic equilibrium

approaches to the disease free equilibrium below this

thresh- old of β. So the disease outbreak can be under

control with the parameter β. On the other hand in paper

[11] authors have shown that the disease transfer rate

from susceptible to incubated population as a bifurcation

parameter. In brief, we can conclude that though the dis-

ease is endemic in nature initially, still in the long run, it

would be possible to control the disease and even if it

may also be eradicated from the society based on the

number of rem ova ble po p ulation from incubated class.

7. Acknowledgements

Authors are thankful to the reviewers for their valuable

comments and suggestions to improve this paper.

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