Nature

14
Jul

‘Out of Control’ Ebola Epidemic Caused by Cutting Down Rainforest

Ebola, the highly lethal hemorrhagic fever that can cause people to bleed out of their eyes and ears, is sweeping through West Africa. The current strain is unrelated to those which caused previous outbreaks in Uganda and Congo, meaning health officials are dealing with a new source, which is likely a bat or ape or some other wild animal. But the real root cause may be deforestation, or rather the activities and proximities to wildlife that accompany it.

The current Ebola outbreak has caused over 500 deaths, making it the largest outbreak on record and prompting an official with Doctors Without Borders to call the epidemic “out of control.” The disease is spread easily through touch, and the best way to limit its spread is to quarantine the sick. But Ebola’s early symptoms are similar enough to other tropical diseases like malaria that patients often aren’t quarantined quickly enough.

deforestation
An industrial logging operation in the Congo basin.

The Associated Press reports:

“We’re under massive time pressure: The longer it takes to find and follow up with people who have come in contact with sick people, the more difficult it will be to control the outbreak,” said Anja Wolz, emergency coordinator for the group, also referred to by its French name Medecins Sans Frontieres.

Quarantining the sick, though, doesn’t necessarily limit the possibility of future outbreaks. Strains of the virus are carried in bats, apes, and other wild animals. As Africa’s frontier regions develop, more and more people are brought into closer contact with the carriers. Unlike smallpox, diseases can’t be eradicated just by treating humans alone, and finding all non-human carriers is so large a task as to be untenable.

Terrence McCoy, reporting for the Washington Post:

Researchers behind the article in the Onderstepoort Journal of Veterinary Research found deforested regions where locals hunted, dug for gold and farmed were most susceptible to an outbreak. The findings landed upon some dismal conclusions: The activities locals depend on the most are also what puts them at the most risk of contracting Ebola.

Ebola isn’t the only disease that’s associated with people living closer to wildlife—yellow fever, Lyme disease, chikungunya, and others are also prevalent at the wildland-urban interface. While Ebola is contained in Africa for the time being, mosquito-borne chikungunya is sweeping the Americas, with over 350,000 suspected cases (pdf). For more on chikungunya, check out NOVA Next contributor Carrie Arnold’s riveting read on the peripatetic virus’s travels around the globe.