MO3 = MODE + MOMA + MOMOS
MO3 enables us to simulate the life cycle of millions of mosquitoes in an artificial urban area. According to meteorological data and the presence of breeding sites, mosquito can lay their eggs; In the presence of humans, they can take blood meal. According to its agenda, a host moves from one place to another, every two hours. During interactions between host and vector, if dengue virus infects one of them, then transmission can occur. It’s then possible to follow step by step the path of the virus diffusion.
MO3 allows us to follow the population dynamic of the vectors at the city scale in order to map the main hot-spots and their environmental features. MO3 allows us to map the main hot-spots of contamination thanks to the record of each events during the simulation. MO3 is then now suitable to explore many hypotheses on dengue virus diffusion at city scale, depending on factors such as seroprevalence in the population, densities of mosquito population, targeted source reduction, climatic conditions. Moreover, informations concerning virus described in the DBVirus database are related for now to dengue virus, but we plan to add informations concerning others virus transmited by Aedes aegypti. Doing so, MO3 should be able to be used to estimate propagation of virus such as Zika or Chikungunia in urban contexts.
Main methods developed and founding during DENFREE project research are:
MOMA: A very detailed agent-based model of Aedes aegypti mosquito governed by dozens parameters and state variables. Numerous simulations can be done using MOMA to experiment hypothesis on population dynamics. Effects of geographical contexts on its capacity of dispersion have been conducted, they show a high sensibility to spatial fragmentation, in the negative sense. Practically, this results in a low capacity to dispersal in very dense areas. We plan to use MOMA to optimize the positioning of auto-dissemination type traps in urban areas where the effectiveness of the intervention is determined by the subsequent dispersal of the mosquitoes.
MODE: MODE is a multi-scale model whose main goal is to generate environmental data for the spatial simulation of Aedes aegypti populations. It is a generic model, mainly based on free access remote sensing images, that can be applied in every intertropical cities. Moreover, it can be used to identify specific neighborhoods at risk of mosquito infestation. Finally, MODE can be used as a perspective exploration tool in order to assess the consequences of climate change or of urban heat island expansion on Aedes aegypti populations.
MOMOS: A model to simulate the human mobility in urban areas. It’s based on the analysis of very large datasets, freely accessible on the Internet, such as social media users’ location and places characteristics, available for mostly every megacities. The inputs are individual schedules, and each simulated person has a probability to do an action in some places. It provides us with realistic mobility patterns usable in MO3 to understand the interactions between humans and mosquitoes. We plan to use results of simulations to target places for source reduction or fumigation by estimate at city-scale the places of infection, result of highest probabilities of interactions between hosts and vectors during the day time.