The impact of natural disasters on the spread of COVID-19: a geospatial, agent based epidemiology model

Van Wyk de Vries, M. S.; Rambabu, L.

Background: Natural disasters and infectious diseases are global issues, resulting in widespread disruption to human health and livelihood. At the scale of a global pandemic, the co-occurrence of natural disasters is inevitable. However, the impact of natural disasters on the spread of COVID-19 has not been extensively evaluated using agent based epidemiology models. Methods: We create an agent-based epidemiology model based on both COVID-19 clinical and epidemiological data and geographic data. We first model 35 scenarios with varying natural disaster timing and duration for a COVID-19 outbreak in a theoretical region. We then evaluate the potential effect of an eruption of Vesuvius volcano on the spread of COVID-19 in Campania, Italy. Our objective is to determine if the occurrence of a natural disaster during the COVID-19 pandemic is likely to increase infection cases and disease related fatalities. Results: In a majority of cases, the occurrence of a natural disaster increases the number of disease related fatalities. When the natural disaster occurs at the beginning of the outbreak within a given region, there is little to no increase in the progression of disease spread. However, the occurrence of a natural disaster close to the peak of infections may increase the number of fatalities by more than five-fold. In a theoretical test case, for a natural disaster that occurred fifty days after first infection case, the median increase in fatalities is 2%, 59%, and 180% for a 2, 14, and 31-day long natural disaster respectively, when compared to the no natural disaster scenario. Conclusion: We propose that the compound risk from natural disasters is greatest in the case of already widespread disease outbreak. The key risk factors for increase in spread of infection and disease related fatalities are the timing of the natural disaster relative to the peak in infections and the duration of the natural disaster.