Deforestation and infectious animal diseases

This paper examines how deforestation in the tropics contributes to the spread of infectious animal diseases. Using geo-referenced data on disease outbreaks and forest loss across 60 countries from 2004 to 2018, we show that a 1% increase in deforestation in neighbouring areas leads to a 1.6% rise in animal infections. We perform several tests to rule our omitted variable bias or measurement error. We find that two mechanisms underpin this effect: (i) habitat destruction increases wildlife-livestock interaction, and (ii) deforestation-linked infrastructure enhances market access, facilitating the transmission of pathogens through animal trade. We also investigate potential zoonotic spillovers. While deforestation on average does not translate into zoonotic transmissions, large shocks may contribute to increases in human infections. Our findings quantify a negative externality of land-use change and underscore how global agricultural demand and infrastructure development can create health risks for animals and humans, highlighting a novel trade-o between economic development and biosecurity.