Vaccination

Vaccination can be represented mathematically by changing susceptibility, infectiousness, disease progression, or movement between compartments, depending on the biological effect being modelled.

A vaccination compartment

A model may introduce a vaccinated class \(V(t)\), with susceptible individuals moving into it at a specified vaccination rate.

Imperfect protection

If vaccination reduces susceptibility rather than eliminating it, a relative susceptibility factor \(0\leq\varepsilon\leq1\) can modify the force of infection experienced by vaccinated individuals.

Model choice

Vaccination should not automatically be represented as complete permanent immunity. The structure should reflect the protection, duration and outcome relevant to the question.