Diseases Don't Just Happen - The Ecology of Disease

[Gert van der Hoek]

Destroying Nature Unleashes Infectious Diseases

July 14, 2012

By JIM ROBBINS

The Ecology of Disease

THERE’S a term biologists and economists use these days — ecosystem services — which refers to the many ways nature supports the human endeavor. Forests filter the water we drink, for example, and birds and bees pollinate crops, both of which have substantial economic as well as biological value.

If we fail to understand and take care of the natural world, it can cause a breakdown of these systems and come back to haunt us in ways we know little about. A critical example is a developing model of infectious disease that shows that most epidemics — AIDS, Ebola, West Nile, SARS, Lyme disease and hundreds more that have occurred over the last several decades — don’t just happen. They are a result of things people do to nature.

The problem is exacerbated by how livestock are kept in poor countries, which can magnify diseases borne by wild animals. A study released earlier this month by the International Livestock Research Institute found that more than two million people a year are killed by diseases that spread to humans from wild and domestic animals.

If a henipah virus evolves to be transmitted readily through casual contact, the concern is that it could leave the jungle and spread throughout Asia or the world. “Nipah is spilling over, and we are observing these small clusters of cases — and it’s a matter of time that the right strain will come along and efficiently spread among people,” says Jonathan Epstein, a veterinarian with EcoHealth Alliance, a New York-based organization that studies the ecological causes of disease.

Full article - NYT