Tropical cyclones affect agriculture and ecosystems by directly damaging plants, disrupting infrastructure, altering pathogen-vector community dynamics, and dispersing pathogens and pests between distant regions. Understanding this dispersal is critical for improved monitoring and risk assessment and for preventing and responding to new outbreaks in the months after a storm. As hosts die and are removed after the events of a cyclone, transmission of pathogen propagules between hosts may be more difficult. Our primary objective is to understand how cyclones connect different parts of the Atlantic basin, potentially allowing for transmission of pathogens and pests. Our secondary objective is to model how death and removal of hosts affects overall epidemic outcomes for an emerging disease. We analyzed historic cyclone path data from the Atlantic basin to understand which countries are connected by storms using a spatio-temporal network analysis. We modeled the impact of reduced host availability and increased vector activity in the period after a major storm using a stochastic spatially-explicit SIDR model based on an emerging plant disease, laurel wilt.
Results/Conclusions
We found that Atlantic basin cyclones connected countries in three main groups: Central America, the Caribbean islands, and greater Atlantic countries, suggesting that pathogen spread due to storms may be more aggregated within the individual groups. We also found that parts of the southeastern US were more frequently affected by cyclones compared with Caribbean countries, although this may be offset by the increased severity of storms affecting islands. We found that the impacts of increased vector activity were more important than reduced host availability for determining disease incidence, likely due to the aggregation of avocado groves in south Florida. However, vector populations may not flourish in the aftermath of a storm if hosts are immediately removed. This model suggests that spread of pathogens between regions may be aggregated due to storm path, and how the effects of storms may be pathosystem specific.