We normally think of infectious diseases such as AIDS, West Nile virus, SARS, Ebola, Lyme disease and others as foreign invaders attacking us. But it turns out that we've largely been responsible for inflicting them upon ourselves.
At least that's the new paradigm in a field that looks at the "ecology of disease" -- or, how our interactions with the environment unleash viruses from wildlife upon human society.
According to this field, which was the topic of a recent New York Times op-ed piece, how do these viruses from wildlife get introduced into the human population and what do human actions in nature have to do with it? Also, what is being done to prevent it?
While infectious diseases have long found their way out of the woods into human society (think plague and malaria), the number of such diseases has quadrupled in the last 50 years. Sixty percent of emerging infectious diseases originate in animals, and more than two-thirds of those originate in wildlife.
The culprits: human encroachment into wildlife habitat, particularly in tropical regions that harbor many diseases, and increased global interconnectedness from both air travel and wildlife trafficking.
Here are several examples of how our interactions with the environment have brought more wildlife diseases to our doorstep:
For more on other infectious diseases that came to us from the wild, check out this beautiful infographic from The Times.
These infectious diseases obviously harm human health: More than two million people a year die from diseases that come from wild and domestic animals, according to a study released earlier this month by the International Livestock Research Institute.
Another huge impact is cost: According to the World Bank, a severe flu epidemic would cost the world as much as $3 trillion.
In order to prevent both negative consequences, several groups are working to better understand the ecology of disease.
Predict, a project funded by the United States Agency for International Development, is working to assess where diseases are likely to emerge based on how people are altering the landscape -- for instance, where they are building a road or farm. The organization is hoping to identify them before disease emerge and before they can spread. The Times reports:
They are gathering blood, saliva and other samples from high-risk wildlife species to create a library of viruses so that if one does infect humans, it can be more quickly identified. And they are studying ways of managing forests, wildlife and livestock to prevent diseases from leaving the woods and becoming the next pandemic.
EcoHealth Alliance and its partners -- the University of California at Davis, the Wildlife Conservation Society, the Smithsonian Institution and Global Viral Forecasting -- are building a virus library of wildlife-originating diseases from the tropics. The group also talks with people who live or work on the edges of forests.
Dr. Peter Daszak, EcoHealth's president, told The Times, "So we're going to the edge of villages, we're going to places where mines have just opened up, areas where new roads are being built. We are going to talk to people who live within these zones and saying, 'what you are doing is potentially a risk.'"
The group may talk with the villagers about how they butcher and eat bush meat or how they handle items that attract species, such as bat, that are likely to carry viruses unsafe for humans. For instance, in Bangladesh, which experienced several Nipah outbreaks, they discovered the culprit were containers collecting date palm sap. They were for people to drink from, but they attracted bats. The group placed bamboo screens over the collectors, preventing bats from contaminating them.
EcoHealth also monitors imported wildlife in airport luggage and packages, and it warns consumers about exotic pets that come from forests known as disease hot spots.
One Health Initiative is a worldwide program that brings together more than 600 scientists and other professionals to promote the idea that human, animal and ecological health are inextricably tied and should be studied and managed holistically.
via: The New York Times
photo: Solipsist/Wikimedia
This post was originally published on Smartplanet.com