Enhancing response preparedness to influenza epidemics: Agent-based study of 2050 influenza season in Switzerland

Abstract

Incidences of seasonal influenza are increasing in severity with significant impacts on human health and on economy, due to missed working hours. As transmission of influenza is highest in spaces where persons are in close proximity, public transport networks are increasingly vulnerable in strategies to manage potential influenza epidemics. In this work, we integrate into an agent-based framework, a stochastic model that simulates, on a sub-hourly timescale, the different daily activities of all individuals in a population. Thus, the contact patterns of individuals are accurately modelled, and with the use of agent-based epidemic and mobility models, individual-level transmission of influenza, and its subsequent spread, are accurately modelled.

We demonstrate this novel approach in an assessment of seasonal influenza in Switzerland for the year 2050, when Switzerland's population will exceed 11 million. In the absence of interventions, we show that, although of shorter duration, future influenza epidemics will be significantly more severe and infect more of the population. The incidence of influenza is larger during leisure and needs activities, rather than at home, school or work. We demonstrate also that influenza-transmission preventive measures are effective: the intensity of the epidemic and the total number of infections are reduced; however, there is little impact of different preventive measures on the duration of the epidemic. This work demonstrates therefore an accurate tool that can predict the spatiotemporal characteristics of an influenza epidemic, and that can be used to assess the most effective measures to mitigate the epidemic.

 Conclusions

• In the absence of interventions that prevent or reduce the transmission of influenza, it is shown that due to the increased population density and the relatively high usage of public transport, future influenza epidemics will be significantly more severe and will infect more of the population; however, the influenza seasons will be of shorter duration than the historical average.
• Furthermore, the simulations show that the incidence of influenza is larger due to leisure and needs activities, rather than activities at home, school, or at work.
• In regards to measures to prevent the transmission of influenza, measures that are effective reduce both the intensity of the epidemic and the total number of infections. However, there is little impact of different preventive measures on the duration of influenza epidemics.