Ebola Rampant in Great Apes

The Ebola crisis has currently killed an estimated 11,205 people, according to the World Health Organization, as of March 11, 2015.  Though is the U.S. Ebola is out of the new, the crisis still exists in West Africa. People continue to die. And what we are not hearing about, so are our cousins, the Great Apes.

The epidemic is now hitting chimpanzees, and according to some reports, lowland gorillas.  The University of Sheffield and Jane Goodall Institute suggests that results are significant.

As with humans, these deaths tend to come in epidemics. In 1995, an outbreak is reported to have killed more than 90% of the gorillas in Minkébé Park in northern Gabon. In 2002-2003 a single outbreak of ZEBOV (the Zaire strain of Ebola) in the Democratic Republic of Congo killed an estimated 5,000 Western gorillas (Gorilla gorilla). It’s hard to accurately count such elusive creatures but the World Wildlife Fund estimates there are up to 100,000 left in the wild – so a single Ebola outbreak wiped out a considerable chunk of the world’s lowland gorilla population. According to some reports, an estimated one third of the world’s gorillas and chimpanzees have been killed by Ebola. 

The good news is that – perhaps because they live further east, or perhaps they are so isolated – the lowland gorilla species cousin, mountain gorillas appear to be (at this moment) protected, according to a source in Rwanda (one of the three nations which mountain gorillas live).

The virus is even more deadly for other great apes as it is for humans, with mortality rates approximately 95% for gorillas and 77% for chimpanzees (Pan troglodytes).

The virus spreading through the great ape populations not only matters for the endangered populations of the apes, but also the potential of the apes spreading the disease right back to nearby human populations, as the disease can bounce back and forth between humans and apes.

The impact on pygmy chimpanzees or bonobos hasn’t been reported. The other great ape species, the orangutan species, are likely potentially affected by ebola but live in Asia (Borneo and Sumatra), so they have not been exposed.

Of course, there are of course additional factors behind the declining numbers of Africa’s great apes: illegal trading in wildlife and bushmeat, war, deforestation at it’s associated affects including an inability to get from one place to another food source without crossing human farm areas,  and other infectious diseases. The world’s remaining wild apes are being increasingly forced into isolated pockets of forest, which impedes their ability to forage, breed and to hide from hunters.

Research has predicted that a single outbreak will take several lifetimes for a given great ape population to recover from – perhaps even longer when other imminent threats (poaching, encroachment, pollution, habitat degradation) are included.