Deforestation and Zoonotic Disease Emergence

In the forests of southern India, areca nuts are a major source of income. But in recent years, rising demand and a growing population has led to deforestation. Areca nut plantations are beginning to pop up where there was once natural, undisturbed forest or grassland.

These transition zones, where natural forest meets new areas of deforestation and manmade plantations, push different wildlife habitats, as well as humans, into closer proximity. Transition zones are major hotspots for the spill-over of zoonotic diseases, epidemiologists warn. Climate change is making things worse, by further disturbing natural feeding and reproduction cycles in the vectors that harbour diseases.

The first outbreak of Kyasanur Forest Disease (KFD), known locally as monkey fever, was in Shimoga, Karnataka in 1957. Since then, the virus has spread to four states across southern India. Epidemiologists believe it has probably been endemic in the forests for centuries, only recently causing outbreaks in human populations because of increased human encroachment into the forest, along with changing rainfall patterns as a result of climate change.

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