Indian vultures: Decline of scavenger birds caused 500,000 human deaths

The authors estimated that between 2000 and 2005, the loss of vultures caused around 100,000 additional human deaths annually, resulting in more than $69bn (£53bn) per year in mortality damages or the economic costs associated with premature deaths.
These deaths were due to the spread of disease and bacteria that vultures would have otherwise removed from the environment.
For example, without vultures, the stray dog population increased, bringing rabies to humans.
Rabies vaccine sales rose during that time but were insufficient. Unlike vultures, dogs were ineffective at cleaning rotting remains, leading to bacteria and pathogens spreading into drinking water through runoff and poor disposal methods. Faecal bacteria in the water more than doubled.
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