Thesis Maud Charron

Maud Charron

Modelling spatio-temporal arboviruses spread, persistence and control: application to the serotype 8 of the bluetongue virus in a cattle population

Abstract :

Arboviruses are pathogens of vector-borne diseases of major concern in public and veterinary health. Their vectors are present all over the world. They are very sensitive to environmental conditions and they have developed adaptation strategies to survive in contrasted climates. The (re)emergence of numerous vector-borne diseases are more and more observed. Our purpose has been to study the spread, persistence and control of such diseases in host populations in seasonal environments. By a modelling approach, we have shown that several mechanisms allow arboviruses to persist during the unfavourable season for their vectors. The virus survival within the host during the unfavourable season seems to be an efficient strategy to adapt to vector seasonal variations. In addition, host vaccination is one of the control strategies of arboviruses. Using a new indicator of the epidemic risk, we have shown that the infection prevalence of bluetongue virus of serotype 8 (BTV8) can be limited with a feasible vaccination strategy. Then, we have evaluated the impact of spatiotemporal heterogeneities in abundance and repartition of hosts and vectors on the spatiotemporal spread of BTV8. We have shown that vector abundance and repartition strongly and not linearly impact virus spread. Mechanistic and flexible models have been developed in this PhD. They can be adapted to other arboviruses transmitted by vectors having comparable biology.

Key words :

Mathematical modelling, vector-borne disease, epidemiology, simulation, spatiotemporal, seasonal environment, sensitivity analysis, vaccination.