COS 220-4 - CANCELLED - Climate change determines transmission hotpots of Polycystic Echinococcosis, a life-threatening zoonotic disease, across Pan-Amazonia

Abstract: At a time when the number of zoonotic spillovers seems to have reached a tipping point and global concerns arise, the question of whether climate change will facilitate them -and if so, where, when and how- remains largely unanswered. In Neotropical forests such as the Amazon rainforest, Polycystic Echinococcosis (PE) is a neglected life-threatening zoonotic disease caused by the cestode Echinococcus vogeli that reaches a case fatality rate of around 29%. PE is naturally sustained in Pan-Amazonia thanks to a complex sylvatic cycle and its infected intermediate hots (especially Cuniculus paca) are key to account for spillover to humans thorough hunting-related behavior. As such, it is a perfect example of a disease acquired at the complex animal-human interface characterizing a wide range of zoonoses with similar pathways of infection. In this study, using a unique extensive dataset of host occurrences, hunting offtakes, disease infections and a suite of modeling and statistical tools, we first unveiled the different spatial distributions of its key animal hosts, along with other ecological, environmental, climatic and hunting covariates encapsulating risk factors of effective spillover to humans. Then, two independent Maximum Entropy (MaxEnt) models, one for E. vogeli animal infections (sylvatic model) and one for E. vogeli human infections (spillover model) were run with the inferred covariates. Both identified trends and variability in both humidity and temperature as key forcing variables. For the first time, climate change is found to determine the spatial structure of PE, a result with far-reaching implications for similarly transmitted zoonoses. More analysis on other rich databases can potentially shed light on a favoring increasing role of climate change on zoonotic spillover in the tropics