Proceedings of the National Academy of Sciences of the United States of America | 2019
Historical and genomic data reveal the influencing factors on global transmission velocity of plague during the Third Pandemic
Abstract
Significance Plague is a devastating infectious disease that has caused three pandemics during the last millennia. Today, plague still causes sporadic cases every year and even some outbreaks. In this paper, we analyze how factors associated with climate change and globalization affect the spread of plague worldwide. Such information is important with respect to global disease prevention and control. For this purpose, we first constructed a global plague database of the Third Pandemic, and then analyzed the association of spatiotemporal environmental factors with spreading velocity. Our results provide insight into the global transmission and suggest strategies for preventing plague transmission under accelerated global change. Quantitative knowledge about which natural and anthropogenic factors influence the global spread of plague remains sparse. We estimated the worldwide spreading velocity of plague during the Third Pandemic, using more than 200 years of extensive human plague case records and genomic data, and analyzed the association of spatiotemporal environmental factors with spreading velocity. Here, we show that two lineages, 2.MED and 1.ORI3, spread significantly faster than others, possibly reflecting differences among strains in transmission mechanisms and virulence. Plague spread fastest in regions with low population density and high proportion of pasture- or forestland, findings that should be taken into account for effective plague monitoring and control. Temperature exhibited a nonlinear, U-shaped association with spread speed, with a minimum around 20 °C, while precipitation showed a positive association. Our results suggest that global warming may accelerate plague spread in warm, tropical regions and that the projected increased precipitation in the Northern Hemisphere may increase plague spread in relevant regions.