M. Gamboa Pérez, M. J. López Herrero
We consider a population of constant size N that is exposed to a contact infectious disease that does not confer immunity after recovery. Infections can be produced either by direct contact with infected individuals within the population or by an external source of infection. As a preventive control measure, a percentage of the population is vaccinated with an imperfect vaccine. As a result of the vaccine failures and the external source of infection, the number of immunized individuals drops down continually and herd immunity could be lost. To control the loss of protection, we introduce a warning threshold for the number of vaccine protected individuals.
We describe the evolution of the epidemic process in terms of a bi-dimensional continuous-time Markov chain and derive theoretical and algorithmic results for the the size of the susceptible group and the time to launch a revaccination programme , just when the warning threshold is reached.
Palabras clave: Stochastic Epidemic Model, Markov Chain, Imperfect Vaccine
Programado
Procesos Estocásticos y sus aplicaciones IV
13 de junio de 2025 09:00
Auditorio 2. Leandre Cristòfol