Time delay in non-lethal infectious diseases


The effects of the incubation period q on the dynamics of non-lethal infectious diseases in a fixed-size population are studied by means of a delay differential equation model. It is noted that the ratio between the quantity q and the time τ for recovering from the illness plays an important role in the onset of the epidemic breakthrough. An approximate analytic expression for the solution of the delay differential equation governing the dynamics of the system is proposed and a comparison is made with the classical SEIR model.

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Luca, R. (2012) Time delay in non-lethal infectious diseases. Natural Science, 4, 562-568. doi: 10.4236/ns.2012.48075.

Conflicts of Interest

The authors declare no conflicts of interest.


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