Modelling distributions of Aedes aegypti and Aedes albopictus using climate, host density and interspecies competition

Florida faces the challenge of repeated introduction and autochthonous transmission of arboviruses transmitted by Aedes aegypti and Aedes albopictus. Empirically-based predictive models of the spatial distribution of these species would aid surveillance and vector control efforts. To predict the occurrence and abundance of these species, we fit a mixed-effects zero-inflated negative binomial regression to a mosquito surveillance dataset with records from more than 200,000 trap days, representative of 53% of the land area and ranging from 2004 to 2018 in Florida. We found an asymmetrical competitive interaction between adult populations of Aedes aegypti and Aedes albopictus for the sampled sites. Wind speed was negatively associated with the occurrence and abundance of both vectors. Our model predictions show high accuracy (72.9% to 94.5%) in validation tests leaving out a random 10% subset of sites and data since 2017, suggesting a potential for predicting the distribution of the two Aedes vectors. Author summary Aedes aegypti and Aedes albopictus are two prime mosquito vectors that transmit emerging arboviral pathogens (e.g. dengue virus, Zika virus and chikungunya virus), which cause substantial disease burden in humans. This study attempts to improve previous studies to map the distribution of Ae. aegypti and Ae. albopictus with greater validation and provide a finer resolution of current and future projections of mosquito populations. We found evidence of an asymmetrical competitive interaction between Aedes vectors where Aedes aegypti is suppressed by Aedes albopictus. In addition to the role of species interactions, abiotic factors, including meteorological factors and human population density, are important predictors of the distribution of these two Aedes mosquito species. Our models demonstrate the potential to predict the occurrence and abundance of the two Aedes vectors, which can enhance domestic mosquito control efforts.