BIODIVERSITY AND HUMAN HEALTH
Executive Summary, page 6
by Joseph Dougherty

The High Cost of Biodiversity Loss

We cannot afford (literally) the high price tag associated with the loss of our planet’s ecosystem services and stores of genetic information.

Affecting Human Health

Government studies show that elevated levels of troubling toxins, including DDT, PCB's, dioxins and synthetic compounds, have infiltrated the food chain through the Columbia River, and that a chemical toxin is concentrated 25 million times by the time it climbs the food chain. Throughout the modern world, our food sources have been seriously compromised. Over 700,000 different chemicals are pumped into our air annually, and that number is growing about 11% per year. Chemicals, herbicides, pesticides, poisons, and pollutants of all types enter the food chain through water, soil, and air, water being our chief food.

Our environment's dangers have weakened our liver, digestive and immune systems. Environmental factors can lead to disease and chronic conditions of fatigue, headaches, sleep disorder, mood swings, depression, confusion, body pain — the symptoms are endless.

Emerging and Re-emerging Infectious Diseases

As humans encroach on previously unoccupied and undisturbed territories, an increasing number of formerly "isolated" viruses are presented with the opportunity to colonize new territories of their own: humans and our domestic animals. In remote rain forest enclaves, high desert plateaus, and mangrove ecosystems around the world, viruses that once lived innocuously in monkeys, bats, and birds are abandoning these dwindling populations and setting up shop in the more numerous species who have supplanted their erstwhile hosts: us. These are emerging diseases, newly discovered pathogens, some of which have the potential to make plague (the “black death” of the middle ages, that killed more than a third of the population of Europe) look like a walk in the park.

In the last 20 years, several hundred new viruses have appeared — and more than five dozen of them infect humans, including: HIV, Sin Nombre Hanta virus, Ebola Ivory Coast, Whitewater Arroyo, Lyme Disease, Hendra virus, Black Lagoon virus, Guanarito virus, Cano Delgadito virus, Black Creek Canal virus, Nipah virus… the list goes on and on. And for every disease that can infect humans, several more are discovered that can infect domestic pets or livestock. These infectious agents are labeled “emerging” due to their recent discovery. As if not to be outdone by their lesser-known cousins, some age-old scourges (such as tuberculosis and measles) are mounting a resurgence of their own.

Not only are a large number of viruses emerging or re-emerging, many are migrating — and this is expected to increase with further global climate change. Jet travel and increased international travel, as well as increased commercial exchange between nations, serves to open the corridors of exchange between places geographically separated by insurmountable obstacles. West Nile virus has emerged in the northeastern United States, killing birds and people.

Viruses are moving into the human species because there are more of us and we're systematically encroaching on every uninhabited corner of the planet. From a virus' point of view, our species is a tantalizingly fresh entrée on the dinner menu. Our bodies are immunologically “virgin” to these invaders and cannot put up a decent defense. From our immune system's point of view, the viruses ambush us with an unanticipated and overwhelmingly violent attack.

Causes of emerging infectious diseases (Institute of Medicine 1992):

• Human behavior and distribution
• Economic development and land use
• International travel and commerce
• Microbial adaptation and change
• Technology and mechanization

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References on this page. Click your browser's "Back" button to return to the spot you were reading.

Institute of Medicine. 1992. Emerging Infections: Microbial Threats to Health in the United States.