Spatial transmission dynamics of African Swine Fever in wild pigs: Sensitivity to epidemiological traits of different viral strains
African Swine Fever virus (ASFv) is a rapidly spreading animal disease with impacts on global economy and food security. Since the first known case of ASFv in Kenya in 1921, the virus has undergone significant evolution resulting in the emergence of 25 distinct genotypes. These genotypes have a wide variety of epidemiological traits, leading to uncertainty about how a genotype or variant of a genotype might spread in a population. Understanding the impacts of different epidemiological traits on the spread of ASFv is important for developing effective surveillance systems and control strategies. We developed a spatial epidemiological model of ASFv transmission in wild pigs, which contributes to ASFv persistence in countries where wild pig populations are widespread. We evaluated the impacts of a realistic set of epidemiological traits including incubation period, infectious period, disease-induced mortality rate, and length of immunity on spatial transmission dynamics under different ecological conditions for the host population (i.e. host density). We analyze effects of these conditions on outbreak metrics using boosted regression models with response variables: peak incidence, rate of spatial spread, seroprevalence and area invaded after one year, and probability that an outbreak will occur. We found that the infectious period of living individuals is the most important predictor at all pig densities for peak incidence and the area affected at one year, followed closely by the incubation period of the virus. We discuss considerations for surveillance and control strategies for different genotypes of ASFv.